PDE4 Inhibitor
The present invention relates to a PDE4 inhibitor. Phosphodiesterase (PDE) is an enzyme that play an important role in the process of degrading and inactivating cyclic nucleotides (cAMP or cGMP), which are important second messengers. PDE degrading cAMP is classified into some isozymes, among which type 4 PDE (PDE4) is a primary cAMP-degrading enzyme present in many inflammatory cells and immunocytes (see Non Patent Literature 1: Expert Opin. Investig. Drugs, 11, 1-13, 2002). PDE4 inhibitors are known to be useful in the treatment of various inflammatory diseases in which TNF-α or the like is involved, because of suppressing the production or release of various cytokines, such as TNF-α, which play an important role in inflammation cascades (see Non Patent Literature 1: Expert Opin. Investig. Drugs, 11, 1-13, 2002). Also, it has been reported that PDE4 inhibitors exhibit effects on not only inflammation in the respiratory system but also inflammation in the skin, and additionally, it has been reported that they also exhibit effects on mental illness (see Non Patent Literature 1: Expert Opin. Investig. Drugs, 11, 1-13, 2002). Theophylline known as a PDE inhibitor has heretofore been used in the treatment of asthma (see Non Patent Literature 2: British Journal of Pharmacology, 155, 308-315, 2008). In recent years, roflumilast, which is a potent PDE4 inhibitor, has been approved and used as a therapeutic drug for chronic obstructive pulmonary disease (COPD) in Europe and the United States (see Non Patent Literature 3: British Journal of Pharmacology, 163, 53-67, 2011), and additionally, the efficacy for interstitial pneumonia (idiopathic pulmonary fibrosis, etc.) in animal models has also been suggested (see Non Patent Literature 4: British Journal of Pharmacology, 156, 534-544, 2009). Moreover, it has been reported that apremilast, which is a PDE inhibitor, is effective for psoriatic arthritis and psoriasis vulgaris in clinical trials (see Non Patent Literature 5: Amadeu G and Richard S. R., Expert Opin. Ther. Patents, August 2013, Vol. 23, No. 8, 997-1016). In addition, clinical trials of PDE4 inhibitors for various inflammatory diseases (inflammatory bowel disease, Crohn's disease, multiple sclerosis, rheumatism, atopic dermatitis and sarcoidosis) have been carried out, and additionally, their possibilities for systemic lupus erythematosus have also been pointed out in nonclinical trials (see Non Patent Literature 1: Expert Opin. Investig. Drugs, 11, 1-13, 2002, and Non Patent Literature 6: BMC Medicine, 11, 96, 2013). Furthermore, among PDE4 inhibitors, there are many compounds having central effects, and there have also been reports on effects on depression, Parkinson's disease, learning and memory disorders and Alzheimer's disease (see Non Patent Literature 1: Expert Opin. Investig. Drugs, 11, 1-13, 2002, and Non Patent Literature 6: BMC Medicine, 11, 96, 2013). Examples of diseases on which PDE4 inhibitors are likely to exhibit effects as described above include asthma, COPD, interstitial pneumonia, inflammatory bowel disease, Crohn's disease, multiple sclerosis, rheumatism, atopic dermatitis, psoriatic arthritis, psoriasis vulgaris, sarcoidosis, systemic lupus erythematosus, depression, learning and memory disorders, Parkinson's disease and Alzheimer's disease. Moreover, although the activity against serotonin 5-HT3of a compound having a structure similar to that of a benzoxazole derivative, which is the active ingredient of the present invention, is described in Patent Literature 1 (JP 6-345744 A), Patent Literature 2 (JP 10-29987 A), etc., there is no description about having PDE4 inhibitory activity. However, these PDE4 inhibitors also include many compounds having emetogenicity, and concentration-dependent side effects such as vomiting and nausea have also been reported. Thus, PDE4 inhibitors that can avoid these side effects have been demanded, and it is considered that such drugs may serve as excellent preventive or therapeutic agents for inflammatory diseases (respiratory diseases and skin diseases) and central nervous system diseases. An object of the present invention is to provide a compound that has excellent PDE4 inhibitory activity and is useful as a pharmaceutical drug. The present inventor has conducted diligent studies to attain the object and consequently completed the present invention by finding that a benzoxazole derivative having a piperazine ring, or a pharmacologically acceptable salt thereof has excellent PDE4 inhibitory activity. Specifically, the present invention provides: [1] A compound represented by formula (1a): wherein R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted C7-11monocyclic or polycyclic aralkyloxy group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylthio group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6(alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a alkyl group, provided that the case where R1is a carboxy group, the case where R1, R2, R3and R4are hydrogen atoms at the same time and the case where R5and R6are hydrogen atoms at the same time are excluded; or a pharmacologically acceptable salt thereof.
R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group. [4] A compound selected from
wherein R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocycle or polycyclic aralkyl group, an optionally substituted 4- to 10-membered monocycle or bicyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted C7-11monocyclic or polycyclic aralkyloxy group, an optionally substituted 4- to 10-membered monocycle or bicyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylthio group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a C1-6alkyl group; or a pharmacologically acceptable salt thereof as an active ingredient.
R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocycle or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocycle heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group. [8] A PDE4 inhibitor comprising a compound represented by formula (1) or a pharmacologically acceptable salt thereof as an active ingredient: wherein R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocycle or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocycle heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5to R8are each independently a hydrogen atom or a C1-6alkyl group. [9] A PDE4 inhibitor comprising the compound or the pharmacologically acceptable salt thereof according to as an active ingredient.
The compound represented by formula (1) or the pharmacologically acceptable salt of the present invention has an excellent PDE4 inhibitory effect and is useful in the treatment or prevention of various diseases caused by PDE4. Examples of the diseases caused by PDE4 include asthma, chronic obstructive pulmonary disease (COPD), interstitial pneumonia, inflammatory bowel disease, Crohn's disease, multiple sclerosis, rheumatism, atopic dermatitis, psoriatic arthritis, psoriasis vulgaris, sarcoidosis, systemic lupus erythematosus, depression, learning and memory disorders, Parkinson's disease and Alzheimer's disease. Hereinafter, the terms used in the present specification will be described specifically. In the present specification, the halogen atom refers to a fluorine atom, a chlorine atom, a bromine atom or an iodine atom and is preferably a fluorine atom, a chlorine atom, a bromine atom or an iodine atom. In the present specification, the C1-6alkyl group refers to a linear or branched alkyl group having 1 to 6 carbon atoms. Examples of the C1-6alkyl group include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, a n-pentyl group, an isoamyl group and a n-hexyl group, and preferred is a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group or an isobutyl group. In the present specification, the C3-7cycloalkyl group refers to a cyclic alkyl group having 3 to 7 carbon atoms. Examples of the C3-7cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group and a cycloheptyl group, and preferred is a cyclopropyl group, a cyclopentyl group or a cyclohexyl group. In the present specification, the C6-10monocyclic or polycyclic aryl group refers to a monocyclic or polycyclic aromatic hydrocarbon group having 6 to 10 carbon atoms. Examples of the C6-10monocyclic or polycyclic aryl group include a phenyl group and a naphthyl group, and preferred is a phenyl group. In the present specification, the C7-11monocyclic or polycyclic aralkyl group refers to an alkyl group having a monocyclic or polycyclic aromatic hydrocarbon group having 7 to 11 carbon atoms. Examples of the C7-11monocyclic or polycyclic aralkyl group include a benzyl group and a naphthylmethyl group, and preferred is a benzyl group. In the present specification, the 4- to 10-membered monocyclic or bicyclic heterocyclic group refers to a 4- to 10-membered monocyclic or bicyclic heterocyclic ring containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom. Examples of the 4- to 10-membered monocyclic or bicyclic heterocyclic group include a tetrahydrofuranyl group, a pyrrolidyl group, a piperidyl group, an oxazolidinyl group, a morpholinyl group, a thienyl group, a furanyl group, a pyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, an isothiazolyl group, an imidazolyl group, a 1,2,3-triazolyl group, a 1,2,4-triazolyl group, a pyridyl group, a pyrimidyl group, an aziridinyl group, a tetrazolyl group, a quinolyl group and an isoquinolyl group, and preferred is a pyrrolidyl group, a morpholinyl group, a thienyl group, a furanyl group, a pyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, an isothiazolyl group, an imidazolyl group, a triazolyl group, a pyridyl group or a pyrimidyl group. In the present specification, the di-C1-6alkylamino group refers to an amino group substituted by two C1-6alkyl groups mentioned above. Examples of the di-C1-6alkylamino group include a dimethylamino group, a diethylamino group and a methylethylamino group, and preferred is a dimethylamino group or a diethylamino group. In the present specification, the C3-7cycloalkylamino group refers to an amino group substituted by the C3-7cycloalkyl group mentioned above. Examples of the C3-7cycloalkylamino group include a cyclobutylamino group, a cyclopentylamino group and a cyclohexylamino group, and preferred is a cyclopentylamino group. In the present specification, the C1-6alkyloxy group refers to a group composed of an oxygen atom substituted by the C1-6alkyl group mentioned above. Examples of the C1-6alkyloxy group include a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group and an isobutoxy group, and preferred is a methoxy group, an ethoxy group, a n-propoxy group or an isopropoxy group. In the present specification, the C3-7cycloalkyloxy group refers to a group composed of an oxygen atom substituted by the C3-7cycloalkyl group mentioned above. Examples of the C3-7cycloalkyloxy group include a cyclopropyloxy group, a cyclobutyloxy group, a cyclopentyloxy group and a cyclohexyloxy group, and preferred is a cyclopentyloxy group or a cyclohexyloxy group. In the present specification, the C6-10monocyclic or polycyclic aryloxy group refers to a group composed of an oxygen atom substituted by the C6-10monocycle or polycyclic aryl group mentioned above. Examples of the C6-10monocycle or polycyclic aryloxy group include a phenyloxy group and a naphthyloxy group, and preferred is a phenyloxy group. In the present specification, the C7-11monocyclic or polycyclic aralkyloxy group refers to a group composed of an oxygen atom substituted by the C7-11monocycle or polycyclic aralkyl group mentioned above. Examples of the C7-11monocyclic or polycyclic aralkyloxy group include a benzyloxy group and a naphthylmethyloxy group, and preferred is a benzyloxy group. In the present specification, the 4- to 10-membered monocycle or bicyclic heterocyclyloxy group refers to a group composed of an oxygen atom substituted by the 4 to 10-membered monocyclic or bicyclic heterocyclic group mentioned above. Examples of the 4- to 10-membered monocyclic or bicyclic heterocyclyloxy group include a thiazolyloxy group and an oxazolyloxy group, and preferred is a thiazolyloxy group. In the present specification, the C1-6alkylthio group refers to a group composed of a sulfur atom substituted by the C1-6alkyl group mentioned above. Examples of the C1-6alkylthio group include a methylthio group, an ethylthio group, a propylthio group and an isopropylthio group, and preferred is a methylthio group. In the present specification, the C1-6alkylsulfonyl group refers to a sulfonyl group substituted by the C1-6alkyl group mentioned above. Examples of the C1-6alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group and a propylsulfonyl group, and preferred is a methylsulfonyl group. In the present specification, the C1-6alkylcarbonyl group refers to a carbonyl group substituted by the C1-6alkyl group mentioned above. Examples of the C1-6alkylcarbonyl group include an acetyl group, an ethylcarbonyl group, a propylcarbonyl group and a butylcarbonyl group, and preferred is an acetyl group. In the present specification, the mono-C1-6alkylaminocarbonyl group refers to an aminocarbonyl group substituted by one C1-6alkyl group mentioned above. Examples of the mono-C1-6alkylaminocarbonyl group include a methylaminocarbonyl group, an ethylaminocarbonyl group and a propylaminocarbonyl group, and preferred is a methylaminocarbonyl group or an ethylaminocarbonyl group. In the present specification, the di-C1-6alkylaminocarbonyl group refers to an aminocarbonyl group substituted by two C1-6alkyl groups mentioned above. Examples of the di-C1-6alkylaminocarbonyl group include a dimethylaminocarbonyl group, a diethylaminocarbonyl group and a dipropylaminocarbonyl group, and preferred is a dimethylaminocarbonyl group or a diethylaminocarbonyl group. In the present specification, the C1-6alkyloxycarbonyl group refers to a carbonyl group substituted by the C1-6alkyloxy group mentioned above. Examples of the C1-6alkyloxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, a n-propoxycarbonyl group and an isopropoxycarbonyl group, and preferred is an ethoxycarbonyl group. In the present specification, the hydroxyaminocarbonyl group refers to a carbonyl group substituted by an amino group substituted by a hydroxy group. In the present specification, a substituent for the term “optionally substituted” can be any substituent as long as it is a group that can substitute each group, and each group may have one or more substituents. Examples of the group that can substitute each group include a halogen atom, a cyano group, a hydroxy group, a C1-6alkyl group, a C3-6cycloalkyl group, a hydroxy-C1-6alkyl group, a C1-6alkyloxy group, an aminocarbonyl group, an oxo group, a nitro group, a C1-6alkylthio group, a C1-6alkylsulfonyl group and a C6-10aryl group. The hydroxy-C1-6alkyl group refers to, for example, a C1-6alkyl group substituted by a hydroxy group and is, for example, a hydroxymethyl group. Also, examples of the C1-6alkyl group substituted by a fluorine atom include a trifluoromethyl group and a trifluoroethyl group, and examples of the C1-6alkyloxy group substituted by a fluorine atom include a trifluoromethoxy group. One embodiment of the present invention is a compound represented by formula (1) or a pharmacologically acceptable salt thereof: In formula (1), the group represented by R1is a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group or an optionally substituted C1-6alkylsulfonyl group and is preferably a hydrogen atom, a fluorine atom, an iodine atom, a cyano group, a methyl group, a trifluoromethyl group, a cyclopropyl group, a phenyl group, a furanyl group, a pyrazolyl group, a methoxy group, a trifluoromethoxy group, a methylthio group or a methylsulfonyl group, more preferably a hydrogen atom, a fluorine atom, an iodine atom, a cyano group, a methyl group, a trifluoromethyl group, a cyclopropyl group, a phenyl group, a furanyl group, a pyrazolyl group, a methoxy group, a trifluoromethoxy group, a methylthio group or a methylsulfonyl group. In formula (1), the group represented by R2is a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group or an optionally substituted 5- to 7-membered monocycle heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom and is preferably a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a methyl group, a trifluoromethyl group, a pyrrolidyl group or a thienyl group, more preferably a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, a methyl group, a trifluoromethyl group or a thienyl group. In formula (1), the group represented by R3is a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group or an optionally substituted C1-6alkyloxy group and is preferably a hydrogen atom, a fluorine atom, an iodine atom, a hydroxy group, a cyano group, a methyl group, a trifluoromethyl group or a methoxy group, more preferably a hydrogen atom, a fluorine atom, a cyano group or a methyl group. In formula (1), the group represented by R4is a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group or an optionally substituted hydroxyaminocarbonyl group and is preferably a hydrogen atom, a bromine atom, a carboxy group, a cyano group, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, a hydroxymethyl group, a cyclohexylmethyl group, a methoxymethyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a benzyl group, a naphthyl group, a tetrahydrofuranyl group, a pyrrolidyl group, an oxopyrrolidyl group, a piperidyl group, an oxazolidinyl group, an oxooxazolidinyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a methylfuranyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a methylimidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, an aziridinyl group, a tetrazolyl group, a quinolyl group, an isoquinolyl group, a dimethylamino group, a diethylamino group, a cyclopentylamino group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a trifluoromethoxy group, a cyclopropylmethoxy group, a cyclopropyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a phenyloxy group, a thiazolyloxy group, a methylsulfonyl group, an acetyl group, a methylaminocarbonyl group, an ethylaminocarbonyl group, a dimethylaminocarbonyl group, a diethylaminocarbonyl group, an ethoxycarbonyl group or a hydroxyaminocarbonyl group, more preferably a hydrogen atom, a bromine atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a methoxymethyl group, a cyclopropyl group, a cyclohexyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a pyrrolidyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, a dimethylamino group, a diethylamino group, an ethoxy group, a propoxy group, an isopropoxy group, a cyclopropylmethoxy group, a cyclopentyloxy group, a cyclohexyloxy group, a methylsulfonyl group or an ethoxycarbonyl group. In formula (1), the groups represented by R5and R6are each independently a hydrogen atom or a C1-6alkyl group and are preferably a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a n-butyl group or an isobutyl group, more preferably a hydrogen atom or a methyl group. In formula (1), the groups represented by R7and R8are each independently a hydrogen atom or a C1-6alkyl group and are preferably a hydrogen atom or a methyl group. According to a preferred embodiment of the present invention, the compound represented by formula (1) or the pharmacologically acceptable salt thereof may be a compound represented by formula (1a) or a pharmacologically acceptable salt thereof Here, in formula (1a), R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted C7-11monocyclic or polycyclic aralkyloxy group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylthio group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a C1-6alkyl group. However, the case where R1is a carboxy group, the case where R1, R2, R3and R4are hydrogen atoms at the same time and the case where R5and R6are hydrogen atoms at the same time are excluded. Also, the compound represented by formula (1) or the pharmacologically acceptable salt thereof may be a compound represented by formula (1b) or a pharmacologically acceptable salt thereof. Here, in formula (1b), R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a hydroxy group, a carboxy group, a cyano group, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, a trifluoromethyl group, a hydroxymethyl group, a cyclohexylmethyl group, a methoxymethyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a benzyl group, a naphthyl group, a tetrahydrofuranyl group, a pyrrolidyl group, an oxopyrrolidyl group, a piperidyl group, an oxazolidinyl group, an oxooxazolidinyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a methylfuranyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a methylimidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, an aziridinyl group, a tetrazolyl group, a quinolyl group, an isoquinolyl group, a dimethylamino group, a diethylamino group, a cyclopentylamino group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a trifluoromethoxy group, a cyclopropylmethoxy group, a cyclopropyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a phenyloxy group, a thiazolyloxy group, a methylthio group, a methylsulfonyl group, an acetyl group, a methylaminocarbonyl group, an ethylaminocarbonyl group, a dimethylaminocarbonyl group, a diethylaminocarbonyl group, an ethoxycarbonyl group and a hydroxyaminocarbonyl group, R5and R6are each independently a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a n-butyl group or an isobutyl group, and R7and R8are hydrogen atoms at the same time. However, the case where R1is a carboxy group, the case where R1, R2, R3and R4are hydrogen atoms at the same time and the case where R5and R6are hydrogen atoms at the same time are excluded. Further, the compound represented by formula (1) or the pharmacologically acceptable salt thereof may be a compound represented by formula (1c) or a pharmacologically acceptable salt thereof: Here, in formula (1c), R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a methoxymethyl group, a trifluoromethyl group, a cyclopropyl group, a cyclohexyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a pyrrolidyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, a dimethylamino group, a diethylamino group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a trifluoromethoxy group, a cyclopropylmethoxy group, a cyclopentyloxy group, a cyclohexyloxy group, a methylthio group, a methylsulfonyl group and an ethoxycarbonyl group, and R5and R6are each independently a hydrogen atom or a methyl group. However, the case where R1is a carboxy group, the case where R1, R2, R3and R4are hydrogen atoms at the same time and the case where R5and R6are hydrogen atoms at the same time are excluded. Moreover, in formula (1c), it is preferable that R2should be one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, and R5and R6should be each independently a hydrogen atom or a C1-6alkyl group. Furthermore, in formula (1c), it is more preferable that R2should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a methyl group, a trifluoromethyl group, a pyrrolidyl group and a thienyl group, and R5and R6should be each independently one group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a n-butyl group and an isobutyl group. Furthermore, in formula (1c) it is further preferable that R2should be one group selected from the group consisting of a fluorine atom, a chlorine atom, a cyano group, a methyl group, a trifluoromethyl, group and a thienyl group, and R5and R6should be each independently a hydrogen atom or a methyl group. Particularly, the compound represented by formula (1) or the pharmacologically acceptable salt thereof may be a compound represented by formula (1d) or a pharmacologically acceptable salt thereof: Here, in formula (1d), R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocycle heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocycle or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocycle heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a C1-6alkyl group, provided that the case where R5and R6are hydrogen atoms at the same time is excluded. In formula (1d), it is preferable that R1should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, an iodine atom, a cyano group, a methyl group, a trifluoromethyl group, a cyclopropyl group, a phenyl group, a furanyl group, a pyrazolyl group, a methoxy group, a trifluoromethoxy group, a methylthio group and a methylsulfonyl group, R2should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, a cyano group, a methyl group, a trifluoromethyl group, a pyrrolidyl group and a thienyl group, R3should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, an iodine atom, a hydroxy group, a cyano group, a methyl group, a trifluoromethyl group and a methoxy group, R4should be one group selected from the group consisting of a hydrogen atom, a bromine atom, a carboxy group, a cyano group, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a tert-butyl group, a hydroxymethyl group, a cyclohexylmethyl group, a methoxymethyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a benzyl group, a naphthyl group, a tetrahydrofuranyl group, a pyrrolidyl group, an oxopyrrolidyl group, a piperidyl group, an oxazolidinyl group, an oxooxazolidinyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a methylfuranyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a methylimidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, an aziridinyl group, a tetrazolyl group, a quinolyl group, an isoquinolyl group, a dimethylamino group, a diethylamino group, a cyclopentylamino group, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a trifluoromethoxy group, a cyclopropylmethoxy group, a cyclopropyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a phenyloxy group, a thiazolyloxy group, a methylsulfonyl group, an acetyl group, a methylaminocarbonyl group, an ethylaminocarbonyl group, a dimethylaminocarbonyl group, a diethylaminocarbonyl group, an ethoxycarbonyl group and a hydroxyaminocarbonyl group, and R5and R6should be each independently one group selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, an isopropyl group, a n-butyl group and an isobutyl group. Moreover, in formula (1d), it is more preferable that R1should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, an iodine atom, a cyano group, a methyl group, a trifluoromethyl group, a cyclopropyl group, a phenyl group, a furanyl group, a pyrazolyl group, a methoxy group, a trifluoromethoxy group, a methylthio group and a methylsulfonyl group, R2should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group, a methyl group, a trifluoromethyl group and a thienyl group, R3should be one group selected from the group consisting of a hydrogen atom, a fluorine atom, a cyano group and a methyl group, R4should be one group selected from the group consisting of a hydrogen atom, a bromine atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a methoxymethyl group, a cyclopropyl group, a cyclohexyl group, a phenyl group, a hydroxymethylphenyl group, a fluorophenyl group, a pyrrolidyl group, a morpholinyl group, a thienyl group, a fluorothienyl group, a chlorothienyl group, a furanyl group, a pyrazolyl group, a methylpyrazolyl group, an oxazolyl group, an isoxazolyl group, an oxadiazolyl group, a thiazolyl group, a chlorothiazolyl group, a cyanothiazolyl group, a methylthiazolyl group, a hydroxymethylthiazolyl group, a carbamoylthiazolyl group, a nitrothiazolyl group, an isothiazolyl group, an imidazolyl group, a triazolyl group, a pyridyl group, a chloropyridyl group, a fluoropyridyl group, a cyanopyridyl group, a methylpyridyl group, a pyrimidyl group, a dimethylamino group, a diethylamino group, an ethoxy group, a propoxy group, an isopropoxy group, a cyclopropylmethoxy group, a cyclopentyloxy group, a cyclohexyloxy group, a methylsulfonyl group and an ethoxycarbonyl group, and R5and R6should be each independently a hydrogen atom or a methyl group. Examples of the compound represented by formula (1) include the following compounds or salts thereof, though the present invention is not intended to be limited by these specific examples:
The compound represented by formula (1) of the present embodiment can be produced by various method, but can be produced by a typical method shown below. A compound represented by formula (2) [wherein R1, R2, R3and R4have the same meanings as those in formula (1), also including preferable forms, and X is a leaving group such as a halogen atom, a thiol group, a p-toluenesulfonyloxy group, a trifluoromethanesulfonyloxy group or a phenoxy group] is reacted with a cyclic diamine represented by formula (3) [wherein R5, R6, R7and R8have the same meanings as those in formula (1), also including preferable forms, and Y is a protective group for the amino group] at 1 equivalent to 50 equivalents with respect to the molar number of the compound represented by formula (2) to obtain a compound represented by formula (4) [wherein R1, R2, R3, R4, R5, R6, R7and R8have the same meanings as those in formula (1), also including preferable forms, and Y has the same meaning as that in formula (3)], and subsequently, Y, which is a protective group, can be removed by a suitable method to thereby obtain the compound represented by formula (1). For example, a tert-butoxycarbonyl group or a benzyloxycarbonyl group described in “Protective Groups in Organic Synthesis” authored by T. W. Greene ((John Wiley and Sons, Inc.), 1991) can be used as the protective group for the amino group. Dichloromethane, chloroform, benzene, toluene, xylene, tetrahydrofuran, diethyl ether, dimethoxyethane, N,N-dimethylformamide, dimethyl sulfoxide or the like can be used as a solvent used in the production method. The reaction temperature is selected from the range of −50 to 200° C., preferably 0 to 150° C., and the reaction time is in the range of 5 minutes to 48 hours, preferably 30 minutes to 20 hours. For the purpose of promoting the reaction or for the purpose of carrying out the reaction under mild conditions, an additive (for example, triethylamine or N,N-diisopropylethylamine) may be added to the production method. The compound represented by formula (4) produced by this method may be derivatized into another compound that falls within the scope of the present invention by subjecting each substituent (R1, R2, R3, R4, R5, R6, R7and R8) to functional group conversion. Examples include the introduction of a functional group by various coupling reactions or the like using a metal catalyst. Typical examples of the coupling reactions include Kumada-Tamao-Corriu coupling, Migita-Kosugi-Stille coupling, Suzuki-Miyaura coupling, Negishi coupling and Buchwald-Hartwig coupling. The compound represented by formula (1) of the present embodiment can exist in the form of an acid-addition salt in addition to the form of a free base. Examples of the acid-addition salt include: salts of hydrohalic acids such as hydrofluoric acid, hydrochloric acid, hydrobromic acid and hydroiodic acid; salts of inorganic acids such as sulfuric acid, nitric acid, phosphoric acid, perchloric acid and carbonic acid; salts of organic carboxylic acids such as acetic acid, trichloroacetic acid, trifluoroacetic acid, hydroxyacetic acid, lactic acid, citric acid, tartaric acid, oxalic acid, benzoic acid, mandelic acid, butyric acid, maleic acid, propionic acid, formic acid and malic acid; salts of acidic amino acids such as aspartic acid and glutamic acid; salts of alkylsulfonic acids such as methanesulfonic acid; and salts of arylsulfonic acids such as p-toluenesulfonic acid. As the compound represented by formula (1) of the present embodiment may have one or two or more asymmetric carbon atoms according to the type of a substituent, optically active forms and diastereomers based on the one or two or more asymmetric carbon atoms, arbitrary mixtures thereof, racemates and the like are all included in the scope of the present invention. Moreover, corresponding hydrates or solvents are also included in the compound represented by formula (1) of the present invention or the pharmacologically acceptable salt thereof. Examples of the solvates include isopropanol solvates. The compound represented by formula (1) of the present embodiment can be used as a PDE4 inhibitor. An alternative embodiment of the present invention is a pharmaceutical composition comprising the compound represented by formula (1) or the pharmacologically acceptable salt thereof as an active ingredient. The pharmaceutical composition of the present embodiment permits any of oral and parenteral administration routes and can be administered to a human or a non-human animal. Thus, the pharmaceutical composition comprising the compound represented by formula (1) of the present embodiment or the pharmacologically acceptable salt thereof as an active ingredient is prepared into an appropriate dosage form according to an administration route. Examples of the pharmaceutical composition specifically include: oral formulations such as tablets, pills, capsules, granules, powders, elixirs, suspensions, emulsions and syrups; and parenteral formulations such as injections, inhalants, formulations for rectal administrations, suppositories, lotions, sprays, ointments, creams and patches. These various formulations can be manufactured by conventional methods using an excipient, a disintegrant, a binder, a lubricant, a colorant and the like usually used in the pharmaceutical field. The content of the compound represented by formula (1) or the pharmacologically acceptable salt thereof in the pharmaceutical composition of the present embodiment differs depending on its dosage form and is usually 0.01 to 50% by mass, preferably 0.05 to 20% by mass, with respect to the total mass of the pharmaceutical composition in terms of a free form. The dosage form is appropriately determined according to each individual case in consideration of the age, body weight, and sex of a patient, difference in disease, the degree of symptoms, etc., and is usually 0.1 to 1000 mg, preferably 1 to 300 mg, per day in an adult, which is administered once a day or in several divided portions per day. The present invention will be described below in more detail with reference to examples, however, the present invention is not limited to these examples. Methods of producing starting material compounds used in the examples will be described as reference examples. Hereinbelow, the abbreviations used in the examples and reference examples have the following meaning. 9-BBN: 9-borabicyclo[3.3.1]nonane ESI: Electronic spray ionization
2-di-tert-butylphosphino-3,4,5,6-tetramethyl-2′,4′,6′-triisopropylbiphenyl
RockPhos: 2-(di-tert-butylphosphino)-3-methoxy-6-methyl-2′-4′-6′-triisopropyl-1,1′-biphenyl
2-Isopropylphenol (1.36 g), 2-aminopyridine (75 mg, 0.08 equivalents), and sulfuryl chloride (803 μL, 1.0 equivalent) were dissolved in toluene (20 mL), and the resulting mixture was stirred in an oil bath at 65° C. for 23 hours. Water was added to the reaction mixture, the product was extracted with ethyl acetate, the organic layer was dried over anhydrous magnesium sulfate, and then the solvent was distilled off under reduced pressure to obtain a crude product. The obtained crude product was purified by silica gel column chromatography (developing solvent, ethyl acetate:hexane=1:15) to obtain 1.29 g of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.27 (6H, d, J=6.8 Hz), 3.14-3.21 (1H, m), 6.67 (1H, d, J=8.4 Hz), 7.01 (1H, dd, J=2.4, 8.4 Hz), 7.14 (1H, d, J=2.4 Hz) 4-Chloro-2-isopropylphenol obtained in Reference Example 1(a) (1.29 g) was dissolved in acetic acid (4.8 mL), and a separately prepared solution of nitric acid (a mixed solution of 70% nitric acid (477 μL) and acetic acid (1.2 mL)) was added dropwise thereto under ice cooling. After the dropping is completed, the resulting mixture was stirred at room temperature for 1.5 hours, then water was added thereto, and the product was extracted with ethyl acetate. The organic layer was washed with an aqueous solution of sodium hydrogencarbonate and then dried over anhydrous magnesium sulfate, and then the solvent was distilled off under reduced pressure to obtain a crude product. The obtained crude product was purified by silica gel column chromatography (developing solvent, ethyl acetate:hexane=1:15) to obtain 882 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.26 (6H, d, J=6.8 Hz), 3.38-3.45 (1H, m), 7.45 (1H, d, J=2.4 Hz), 7.96 (1H, d, J=2.4 Hz), 10.97 (1H, s) 4-Chloro-2-isopropyl-6-nitrophenol obtained in Reference Example 1(b) (881 mg) was dissolved in acetic acid (8.8 mL) and ethanol (8.8 mL), 5% platinum on sulfide carbon (264 mg) was added thereto, and the resulting mixture was stirred at room temperature in a hydrogen atmosphere for 30 minutes. The insoluble matter was filtered off, and then the solvent was distilled off under reduced pressure to obtain 745 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.23 (6H, d, J=6.8 Hz), 3.03-3.10 (1H, m), 6.63-6.65 (2H, m) 2-Amino-4-chloro-6-isopropylphenol obtained in Reference Example 1(c) (745 mg) was dissolved in ethanol (13.4 mL), carbon disulfide (6.7 mL) and potassium hydroxide (120 mg) were added thereto, and the resulting mixture was stirred in an oil bath at 60° C. for 2 hours. The solvent was distilled off from the reaction mixture under reduced pressure, and then water was added to the residue and further acidified with 5 N hydrochloric acid. The precipitate was filtered off and dried to obtain 937 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.33 (6H, d, J=6.8 Hz), 3.28-3.35 (1H, 7.04 (1H, d, J=2 Hz), 7.09 (1H, d, J=2 Hz) MS(ESI) m/z: 228(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-chloro-2-methoxyphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2-methoxy-6-nitrophenol obtained in Reference Example 2(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. 1H-NMR (400 MHz, CDCl3) δ: 3.84 (3H, s), 6.34 (1H, d, J=2.4 Hz), 6.39 (1H, d, J=2.4 Hz) The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-6-methoxyphenol obtained in Reference Example 2(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 216(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(c) except that 5′-chloro-2′-hydroxy-3′-nitroacetophenone was used instead of 4-chloro-2-isopropyl-6-nitrophenol. 1H-NMR (400 MHz, CDCl3) δ: 2.59 (3H, s), 4.02-4.04 (2H, br s), 6.83 (1H, s), 7.08 (1H, s), 12.41 (1H, s) The title compound was obtained in a similar manner as in Reference Example 1(d) except that 3′-amino-5′-chloro-2′-hydroxyacetophenone obtained in Reference Example 3(a) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, CD3OD) δ: 2.75 (3H, s), 7.39 (1H, d, J=2.4 Hz), 7.65 (1H, d, J=2.4 Hz) MS(ESI) m/z: 228(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-fluoro-2-methylphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-fluoro-2-methyl-6-nitrophenol obtained in Reference Example 4(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. 1H-NMR (400 MHz, CD3OD) δ: 2.16 (3H, s), 6.16-6.20 (1H, m), 6.31 (1H, dd, J=2.4, 10.0 Hz) MS(ESI) m/z: 142(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-fluoro-6-methylphenol obtained in Reference Example 4(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, CD3OD) δ: 2.42 (3H, s), 6.78-6.86 (2H, m) MS(ESI) m/z: 184(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-bromo-2-methylphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-bromo-2-methyl-6-nitrophenol obtained in Reference Example 5(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. 1H-NMR (400 MHz, CD3OD) δ: 2.15 (3H, s), 6.57 (1H, s), 6.71 (1H, s) The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-bromo-6-methylphenol obtained in Reference Example 5(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 2.36 (3H, s), 7.21 (1H, s), 7.31 (1H, s) MS(ESI) m/z: 243(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-isopropoxyphenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-chloro-2-isopropoxyphenol obtained in Reference Example 6(a) was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2-isopropoxy-6-nitrophenol obtained in Reference Example 6(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-6-isopropoxyphenol obtained in Reference Example 6(c) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 1.31 (6H, d, J=2 Hz), 4.85 (1H, m), 6.84 (1H, s), 7.03 (1H, s) MS(ESI) m/z: 242(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-ethylphenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-chloro-2-ethylphenol obtained in Reference Example 7(a) was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2-ethyl-6-nitrophenol obtained in Reference Example 7(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-6-ethylphenol obtained in Reference Example 7(c) was used instead of 2-amino-4-chloro-6-ethylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 5-chloro-2-hydroxybenzonitrile was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2-cyano-6-nitrophenol obtained in Reference Example 8(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-6-cyanophenol obtained in Reference Example 8(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 209(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chlorophenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-6-nitrophenol obtained in Reference Example 8(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-chlorophenol obtained in Reference Example 8(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 262(M−H)− 4-Chloro-3-(trifluoromethyl)phenol (5.0 g) was dissolved in acetic acid (50 mL), then bromine (1.54 mL, 1.2 equivalents) was added thereto, and the resulting mixture was stirred at room temperature for 7 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate and chloroform. The organic layer was dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure to obtain a crude product. The obtained crude product was purified by silica gel column chromatography (developing solvent, chloroform) to obtain 1.88 g of a mixture of 2-bromo-4-chloro-5-(trifluoromethyl)phenol and 2-bromo-4-chloro-3-(trifluoromethyl)phenol. The obtained mixture (826 mg) was dissolved in acetic acid (3.0 mL), then 70% nitric acid (380 viL) was added thereto under ice cooling, and the resulting mixture was stirred for 1 hour in this state. After that, the resulting mixture was stirred at room temperature for 1 hour, then water was added thereto, and the product was extracted with ethyl acetate. The organic layer was washed with water and a saturated saline solution sequentially and dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the obtained residue was purified by silica gel column chromatography (developing solvent, chloroform) to obtain 323 mg of the compound of Title (a) and 142 mg of the compound of Title (b). The title compound was obtained in a similar manner as in Reference Example 1(c) except that 6-bromo-4-chloro-2-nitro-3-(trifluoromethyl)phenol obtained in Reference Example 10(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-chloro-6-(trifluoromethyl)phenol obtained in Reference Example 10(c) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 330(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-6-nitro-3-(trifluoromethyl)phenol obtained in Reference Example 10(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-2-bromo-4-chloro-3-(trifluoromethyl)phenol obtained in Reference Example 11(a) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 330(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-5-(trifluoromethoxy)phenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chloro-5-(trifluoromethoxy)phenol obtained in Reference Example 12(a) was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 6-bromo-4-chloro-2-nitro-3-(trifluoromethoxy)phenol obtained in Reference Example 12(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-chloro-3-(trifluoromethoxy)phenol obtained in Reference Example 12(c) was used instead of 2-amino-4-chloro-6-ethylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 7.84 (1H, s) MS(ESI) m/z: 346(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4,5-difluorophenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that the whole quantity of 6-bromo-3,4-difluoro-2-nitrophenol obtained in Reference Example 13(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-3,4-difluorophenol obtained in Reference Example 13(b) was used instead of 2-amino-4-chloro-6-ethylphenol. MS(ESI) m/z: 264(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-3-fluorophenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chloro-3-fluorophenol obtained in Reference Example 14(a) was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-3-fluoro-6-nitrophenol obtained in Reference Example 14(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 14(d) except that 6-amino-2-bromo-4-chloro-3-fluorophenol obtained in Reference Example 14(c) was used instead of 2-amino-4-chloro-6-ethylphenol. MS(ESI) m/z: 280(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-chloro-2-n-propylphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2-nitro-6-n-propylphenol obtained in Reference Example 15(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-6-n-propylphenol obtained in Reference Example 15(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) 228(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-fluorophenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-fluoro-6-nitrophenol obtained in Reference Example 16(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-fluorophenol obtained in Reference Example 16(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 246(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 3-bromo-4-hydroxybenzonitrile was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 3-bromo-4-hydroxy-5-nitrobenzonitrile obtained in Reference Example 17(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 3-amino-5-bromo-4-hydroxybenzonitrile obtained in Reference Example 17(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) in/z: 253(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-methylphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-methyl-6-nitrophenol obtained in Reference Example 18(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-methylphenol obtained in Reference Example 18(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 242(M−H)− The title compound was obtained in a similar manner as in Reference Examples 10(a) and 10(b) as a mixture except that 4-fluoro-3-(trifluoromethyl)phenol was used instead of 4-chloro-3-(trifluoromethyl)phenol. The title compound was obtained in a similar manner as in Reference Example 1(c) as a mixture except that a mixture of 6-bromo-4-fluoro-2-nitro-3-(trifluoromethyl)phenol and 2-bromo-4-fluoro-6-nitro-3-(trifluoromethyl)phenol obtained in Reference Example 19(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that a mixture of 2-amino-6-bromo-4-fluoro-3-(trifluoromethyl)phenol and 6-amino-2-bromo-4-fluoro-3-(trifluoromethyl)phenol obtained in Reference Example 19(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 314(M−H)− The title compound was obtained in a similar manner as in Reference Examples 10(a) and 10(b) except that 4-chloro-3,5-difluorophenol was used instead of 4-chloro-3-(trifluoromethyl)phenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-3,5-difluoro-6-phenol obtained in Reference Example 20(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-chloro-3,5-difluorophenol obtained in Reference Example 20(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 298(M−H)− The title compound was obtained in a similar manner as in Reference Examples 10(a) and 10(b) except that 3,4,5-trifluorophenol was used instead of 4-chloro-3-(trifluoromethyl)phenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-3,4,5-trifluoro-6-nitrophenol obtained in Reference Example 21(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-3,4,5-trifluorophenol obtained in Reference Example 21(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 282(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-methylphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-6-nitro-4-(trifluoromethyl)phenol obtained in Reference Example 22(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-(trifluoromethyl)phenol obtained in Reference Example 22(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 296(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-5-fluorophenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chloro-5-fluorophenol obtained in Reference Example 23(a) was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-5-fluoro-6-nitrophenol obtained in Reference Example 23(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-2-bromo-4-chloro-3-fluorophenol obtained in Reference Example 23(c) was used instead of 2-amino-4-chloro-6-ethylphenol. MS(ESI) 280(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-5-methylphenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chloro-5-methylphenol obtained in Reference Example 24(a) was used instead of 4-chloro-2-isopropylphenol and that chloroform was used instead of acetic acid. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-5-methyl-6-nitrophenol obtained in Reference Example 24(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-2-bromo-4-chloro-5-methylphenol obtained in Reference Example 24(c) was used instead of 2-amino-4-chloro-6-ethylphenol. 1H-NMR (400 MHz, CDCl3) 6:2.36 (3H, s), 7.42 (1H,$), 10.06 (1H, br s) MS(ESI) m/z: 276(M−H)− The title compound was obtained in a similar manner as in Reference Examples 10(a) and 10(b) except that 4-fluoro-3-(trifluoromethoxy)phenol was used instead of 4-chloro-3-(trifluoromethyl)phenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 6-bromo-4-fluoro-2-nitro-3-(trifluoromethoxy)phenol obtained in Reference Example 25(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-fluoro-3-(trifluoromethoxy)phenol obtained in Reference Example 25(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 330(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-3-methylphenol was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 2-bromo-4-chloro-5-methylphenol obtained in Reference Example 26(a) was used instead of 4-chloro-2-isopropylphenol and that chloroform was used instead of acetic acid. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-3-methyl-6-nitrophenol obtained in Reference Example 26(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-2-bromo-4-chloro-5-methylphenol obtained in Reference Example 26(c) was used instead of 2-amino-4-chloro-6-ethylphenol. 1H-NMR (400 MHz, CDCl3) δ: 2.55 (3H, s), 7.17 (1H, s), 10.24 (1H, br s) MS(ESI) in/z: 276(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(a) except that 2-bromo-5-methoxyphenol was used instead of 2-isopropylphenol. 1H-NMR (400 MHz, CDCl3) δ: 3.83 (3H, s), 6.65 (1H, s), 7.43 (1H, s) 2-Bromo-4-chloro-5-methoxyphenol (2:15 g) obtained in Reference Example 27(a) was dissolved in ethyl acetate (21.5 mL), and 70% nitric acid (1.15 mL) was added dropwise thereto under ice cooling After the dropping was completed, concentrated sulfuric acid (0.3 mL) was added while stirring the resulting mixture at room temperature, and the reaction mixture was further stifled for 22 hours. Ethyl acetate was added to the reaction mixture, the organic layer was sequentially washed with an aqueous solution of sodium hydrogencarbonate and a saturated saline solution and then dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure to obtain a crude product. This crude product was purified by silica gel column chromatography (developing solvent, ethyl acetate:hexane=1:8) to obtain 1.21 g of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 4.01 (3H, s), 8.22 (1H, s), 11.25 (1H, s) The title compound was obtained in a similar manner as in Reference Example 1(c) except that 2-bromo-4-chloro-3-methoxy-6-nitrophenol obtained in Reference Example 27(b) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-2-bromo-4-chloro-3-methoxyphenol obtained in Reference Example 27(c) was used instead of 2-amino-4-chloro-6-ethylphenol. 1H-NMR (500 MHz, CDCl3) δ: 3.92 (3H, s), 7.16 (1H, s) MS(EI) m/z: 293(M+) The title compound was obtained in a similar manner as in Reference Examples 10(a) and 10(b) as a mixture except that 2-chloro-5-hydroxybenzonitrile was used instead of 4-chloro-3-(trifluoromethyl)phenol. The title compound was obtained in a similar manner as in Reference Example 1(c) as a mixture except that a mixture of 4-bromo-6-chloro-3-hydroxy-2-nitrobenzonitrile and 2-bromo-6-chloro-3-hydroxy-4-nitrobenzonitrile obtained in Reference Example 28(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that a mixture of 2-amino-4-bromo-6-chloro-3-hydroxybenzonitrile and 4-amino-2-bromo-6-chloro-3-hydroxybenzonitrile obtained in Reference Example 28(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 287(M−H)− In Reference Example 12(b), the title compound was obtained as a byproduct at the same time in which 6-bromo-4-chloro-2-nitro-3-(trifluoromethoxy)phenol was obtained. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 6-bromo-4-chloro-2-nitro-5-(trifluoromethoxy)phenol obtained in Reference Example 29(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-6-bromo-4-chloro-5-(trifluoromethoxy)phenol obtained in Reference Example 29(b) was used instead of 2-amino-4-chloro-6-ethylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 7.54 (1H, s) The title compound was obtained in a similar manner as in Reference Example 1(a) except that 1,3-dimethoxy-2-methylbenzene was used instead of 2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(b) except that 1-chloro-2,4-dimethoxy-3-methylbenzene obtained in Reference Example 30(a) was used instead of 4-chloro-2-isopropylphenol. 1-Chloro-2,4-dimethoxy-3-methyl-5-nitrobenzene obtained in Reference Example 30(b) (1.77 g) was dissolved in dichloromethane (20 mL), boron tribromide (a 1 M solution in dichloromethane, 9.5 mL) was added thereto at −78° C., and then the resulting mixture was stirred for 70 minutes in this state. Water was added to the reaction mixture, and the product was extracted with dichloromethane. The organic layer was dried over magnesium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel chromatography (developing solvent, n-hexane:ethyl acetate=10:1) to obtain 1.25 g of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 2.28 (3H, s), 3.90 (3H, s), 8.06 (1H, s), 10.97 (1H, s) The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-3-methoxy-2-methyl-6-nitrophenol obtained in Reference Example 30(c) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-4-chloro-3-methoxy-2-methylphenol obtained in Reference Example 30(d) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 2.34 (3H, s), 3.76 (3H, s), 7.19 (1H, s) The title compound was obtained in a similar manner as in Reference Example 30(c) except that 2-bromo-4-chloro-6-methoxyaniline was used instead of 1-chloro-2,4-dimethoxy-3-methyl-5-nitrobenzene and that the reaction was performed at room temperature. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-3-bromo-5-chlorophenol obtained in Reference Example 31(a) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 262(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-bromophenol was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 7.39-7.48 (3H, m) MS(ESI) m/z: 230(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-hydroxy-3-methoxybenzonitrile was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-hydroxy-3-methoxy-5-nitrobenzonitrile obtained in Reference Example 33(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 3-amino-4-hydroxy-5-methoxybenzonitrile obtained in Reference Example 33(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. 1H-NMR (400 MHz, DMSO-d6) δ: 3.97 (3H, s), 7.34 (1H, s), 7.48 (1H, s) MS(ESI) m/z: 207(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(b) except that 4-chloro-2,3-dimethoxyphenol was used instead of 4-chloro-2-isopropylphenol. The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-2,3-dimethoxy-6-nitrophenol obtained in Reference Example 34(a) was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 6-amino-4-chloro-2,3-dimethoxyphenol obtained in Reference Example 34(b) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 246(M+H)+ The title compound was obtained in a similar manner as in Reference Example 1(c) except that 4-chloro-5-methyl-2-nitrophenol was used instead of 4-chloro-2-isopropyl-6-nitrophenol. The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-5-methylphenol obtained in Reference Example 35(a) was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 198(M−H)− The title compound was obtained in a similar manner as in Reference Example 1(d) except that 2-amino-4-chloro-5-methoxyphenol was used instead of 2-amino-4-chloro-6-isopropylphenol. MS(ESI) m/z: 214(M−H)− 5-Chloro-7-isopropyl-2-mercaptobenzoxazole obtained in Reference Example 1 (203 mg) and (S)-1-tert-butoxycarbonyl-3-methylpiperazine (357 mg, 2.0 equivalents) were dissolved in xylene (2.0 mL), and the resulting mixture was stirred in an oil bath at 140° C. overnight. TLC (developing solvent, hexane:ethyl acetate=3:1) was carried out to verify that the starting material had vanished, then 1 N hydrochloric acid was added to weakly acidify the reaction mixture, and the product was extracted with ethyl acetate. A 4 N solution of hydrogen chloride/dioxane was added to the extract, and the resulting mixture was stirred at room temperature, TLC (developing solvent, ethyl acetate:methanol=10:1) was carried out to verify that the target product had been produced, then water was added thereto, and the product was extracted from the organic layer. A 5 N aqueous solution of sodium hydroxide was added to the water layer for neutralization, then the resulting mixture was extracted with ethyl acetate and dried over anhydrous magnesium sulfate, and then the solvent was distilled off under reduced pressure to obtain 181 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.32 (6H, d, J=6.8 Hz), 1.39 (3H, d, J=6.8 Hz), 2.85-2.93 (2H, m), 3.01-3.11 (2H, m), 3.14-3.21 (1H, m), 3.37 (1H, dt, J=3.6, 12.8 Hz), 3.95-3.98 (1H, m), 4.35-4.40 (1H, m), 6.84 (1H, d, J=2.4 Hz), 7.15 (1H, d, J=2.4 Hz) MS(ESI) m/z: 294(M+H)+ 5-Chloro-7-methoxy-2-mercaptobenzoxazole obtained in Reference Example 2 (80 mg) and (S)-1-tert-butoxycarbonyl-3-methylpiperazine (149 mg, 2.0 equivalents) were dissolved in xylene (1.6 mL), and the resulting mixture was stirred in an oil bath at 140° C. overnight. TLC (developing solvent, dichloromethane) was carried out to verify that the starting material had vanished, then 1 N hydrochloric acid was added to weakly acidify the reaction mixture, and the product was extracted with ethyl acetate. A 4 N solution of hydrogen chloride/dioxane was added to the extract, the resulting mixture was stirred at room temperature, and TLC (developing solvent, dichloromethane:methanol=5:1) was carried out to verify that the target product had been produced, then water was added thereto, and the product was extracted from the organic layer. A 5 N aqueous solution of sodium hydroxide was added to the water layer for neutralization, then the reaction mixture was extracted with ethyl acetate and dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by preparative TLC (developing solvent, ethyl acetate:methanol=5:1) to obtain 23 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 2.83-2.92 (2H, m), 3.05-3.11 (2H, m), 3.38(1H, dt, J=3.2, 12.4 Hz), 3.95 (3H, s), 3.96-4.00 (1H, m), 4.39-4.43 (1H, m), 6.60 (1H, d, J=1.6 Hz), 6.97 (1H, d, J=1.6 Hz) MS(ESI) m/z: 282(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 7-acetyl-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 3 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.72 (3H, s), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.43(1H, dt, J=3.6, 12.4 Hz), 3.98-4.01 (1H, m), 4.39-4.43 (1H, m), 7.45 (1H, d, J=2.0 Hz), 7.51 (1H, d, J=2.0 Hz) MS(ESI) m/z: 294(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-methyl-2-mercaptobenzoxazole and (3S,5R)-1-tert-butoxycarbonyl-3,5-dimethylpiperazine. 1H-NMR (400 MHz, CDCl3) 6:1.44 (6H, d, J=6.8 Hz), 2.38 (3H, s), 2.91-3.06 (4H, m), 4.24-4.32 (2H, m), 6.79 (1H, d, J=2 Hz), 7.15 (1H, d, J=2 Hz) The title compound was obtained in a similar manner as in Example 2 from 5-fluoro-7-methyl-2-mercaptobenzoxazole obtained in Reference Example 4 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.38 (3H, s), 2.83-2.92 (2H, m), 3.06-3.10 (2H, m), 3.36(1H, dt, J=3.6, 12.4 Hz), 3.95-3.99 (1H, m), 4.38-4.41 (1H, m), 6.53 (1H, dd, J=2.4, 10.4 Hz), 6.87 (1H, dd, J=2.4, 8.8 Hz) MS(ESI) m/z: 250(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-bromo-7-methyl-2-mercaptobenzoxazole obtained in Reference Example 5 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.37 (3H, s), 2.89-2.92 (2H, m), 3.06-3.10 (2H, m), 3.32-3.40 (1H, m), 3.95-3.99 (1H, m), 4.39-4.42 (1H, m), 6.95 (1H, d, J=1.2 Hz), 7.28 (1H, d, J=1.2 Hz) MS(ESI) m/z: 310(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-isopropoxy-2-mercaptobenzoxazole obtained in Reference Example 6 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38-1.40 (9H, m), 2.84-2.92 (2H, m), 3.07-3.10 (2H, m), 3.33-3.39 (1H, m), 3.96-3.99 (1H, m), 4.38-4.41 (1H, m), 4.65-4.70 (1H, m), 6.61 (1H, d, J=2.0 Hz), 6.95 (1H, d, J=2.0 Hz) MS(ESI) m/z: 310(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.30 (3H, t, J=7.6 Hz), 1.40 (3H, d, J=6.8 Hz), 2.76(2H, q, J=7.6 Hz), 2.91 (2H, m), 3.09 (2H, m), 3.37 (1H, m), 3.97 (1H, m), 4.39 (1H, m), 6.83 (1H, d, J=2.0 Hz), 7.15 (1H, d, J=2.0 Hz) MS(ESI) m/z: 280(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethoxycarbonyl-2-mercaptobenzoxazole and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) 6:1.42 (3H, d, J=7.1 Hz), 1.43 (3H, t, J=7.3 Hz), 2.84-2.93 (2H, m), 3.07-3.11 (2H, m), 3.37-3.45 (1H, m), 4.00-4.04 (1H, m), 4.39-4.45 (3H, m), 7.44 (1H, d, J=2.2 Hz), 7.56 (1H, d, J=2.2 Hz) MS(ESI) m/z: 324(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-cyano-2-mercaptobenzoxazole obtained in Reference Example 8 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) 6:1.43 (3H, d, J=6.8 Hz), 2.83-2.96 (2H, m), 3.04-3.15 (2H, m), 3.38-3.46 (1H, m), 3.99-4.06 (1H, m), 4.38-4.46 (1H, m), 7.20 (1H, d, J=2 Hz), 7.45 (1H, d, J=2 Hz) MS(ESI) m/z: 277(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (S)-1-tert-butoxycarbonyl-3-isopropylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.90 (3H, d, J=6.8 Hz), 1.05 (3H, d, J=6.6 Hz), 1.30 (3H, t, J=7.6 Hz), 2.44-2.54 (1H, m), 2.70-2.95 (4H, m), 3.00-3.07 (1H, m), 3.18-3.34 (2H, m), 3.77-3.83 (1H, m), 4.06-4.14 (1H, m), 6.80 (1H, d, J=2 Hz), 7.12 (1H, d, J=2 Hz) MS(ESI) m/z: 308(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (S)-1-tert-butoxycarbonyl-3-isobutylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.89 (3H, t, J=7 Hz), 1.25-1.50 (6H, m), 1.57 (2H, m), 1.67-1.76 (2H, m), 2.72-2.84 (2H, m), 2.85-3.15 (2H, m), 3.29-3.38 (1H, m), 4.02-4.28 (3H, m), 6.84 (1H, d, J=2 Hz), 7.14 (1H, d, J=2 Hz) MS(ESI) m/z: 322(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (S)-1-tert-butoxycarbonyl-3-n-butylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.89 (3H, t, J=7 Hz), 1.25-1.40 (7H, m), 1.74-1.94 (2H, m), 2.71-2.79 (2H, m), 2.82-2.91 (1H, m), 2.96-3.08 (3H, m), 3.30-3.38 (1H, m), 4.00-4.06 (1H, m), 4.17-4.24 (1H, m), 6.81 (1H, d, J=2 Hz), 7.13 (1H, d, J=2 Hz) MS(ESI) m/z: 322(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (S)-1-tert-butoxycarbonyl-3-ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.95 (3H, t, J=7.6 Hz), 1.30 (3H, t, J=7.6 Hz), 1.78-1.97 (2H, m), 2.72-2.80 (2H, m), 2.83-2.91 (1H, m), 3.00-3.09(3H, m), 3.28-3.36 (1H, m), 4.00-4.06 (1H, m), 4.10-4.16 (1H, m), 6.81 (1H, d, J=2 Hz), 7.13 (1H, d, J=2 Hz) MS(ESI) m/z: 294(M+1-1)+ 5-Chloro-7-ethoxycarbonyl-2-mercaptobenzoxazole (1.03 g) and (S)-1-tert-butoxycarbonyl-3-methylpiperazine (1.60 g, 2.0 equivalents) were dissolved in xylene (10 mL), and the resulting mixture was stirred in an oil bath at 140° C. overnight. TLC (developing solvent, hexane:ethyl acetate=4:1) was carried out to verify the product, then 1 N hydrochloric acid was added thereto to weakly acidify the reaction mixture, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with a saturated saline solution and dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=7:3) to obtain 1.16 g of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-ethoxycarbonylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 15(a) (370 mg) was dissolved in 1,4-dioxane (9 mL), a 1 N aqueous solution of sodium hydroxide (1.74 mL) was added under ice cooling, and then the resulting mixture was stirred at room temperature for 18 hours. Water was added to the reaction mixture, the resulting mixture was washed with diethyl ether, then a 1% aqueous solution of citric acid was added to the water layer for neutralization. The product was extracted from the water layer with ethyl acetate and dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure to obtain 342 mg of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-carboxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 15(b) (40 mg) was dissolved in THF (1 mL), borane (a 1 M solution in THF, 0.2 mL) was added thereto under ice cooling, and then the resulting mixture was stirred for 2 hours in this state. The reaction mixture was heated up to room temperature and then was further stirred for 4 hours, then ammonium chloride (53 mg) and water were added thereto, and the product was extracted with ethyl acetate. The organic layer was washed with a saturated saline solution and then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by preparative TLC (developing solvent, chloroform:methanol=9:1) to obtain 30 mg of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(hydroxymethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 15(c) (29 mg) was dissolved in dichloromethane (0.8 mL), then trifluoroacetic acid (0.4 mL) was added thereto, and the resulting mixture was stirred at room temperature for 1 hour. A 5% aqueous solution of sodium hydrogencarbonate was added to the reaction mixture, the product was extracted with ethyl acetate, then the organic layer was washed with a saturated saline solution and dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=9:1) to obtain 12 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 2.83-2.92 (2H, m), 3.06-3.11 (2H, m), 3.34-3.41 (1H, m), 3.95-3.99 (1H, m), 4.37-4.24 (1H, m), 4.84 (2H, s), 7.04 (1H, d, J=2.0 Hz), 7.24 (1H, d, J=2.2 Hz) MS(ESI) m/z: 282(M+H)+ 7-Bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 (500 mg) and (S)-1-tert-butoxycarbonyl-3-methylpiperazine (757 mg, 2.0 equivalents) were dissolved in xylene (5 mL), and the resulting mixture was stirred in an oil bath at 140° C. overnight. TLC (developing solvent, hexane:ethyl acetate=2:1) was carried out to verify the product, then 1 N hydrochloric acid was added thereto to weakly acidify the reaction mixture, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with a saturated saline solution and dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=5:1) to obtain 613 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.32 (3H, d, J=6.8 Hz), 1.50 (9H, s), 2.27-2.30 (1H, m), 3.18-3.21 (1H, m), 3.42(1H, dt, J=3.6, 12.8 Hz), 3.80-3.82 (1H, m), 4.01-4.05 (1H, m), 4.22-4.25 (1H, m), 4.45-4.48 (1H, m), 7.15 (1H, d, J=1.6 Hz), 7.23 (1H, d, J=1.6 Hz) MS(ESI) m/z: 430(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (120 mg), potassium carbonate (85 mg, 2.2 equivalents), and 3-thiophene boronic acid (43 mg, 1.2 equivalents) were dissolved in toluene (1.6 mL) and ethanol (0.4 mL), the resulting mixture was stirred in an argon atmosphere for 15 minutes, then tetrakis(triphenylphosphine)palladium(0) (16 mg, 0.05 equivalents) was added thereto, and the resulting mixture was heated under reflux for 2 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=4:1) to obtain 74 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.33 (3H, d, J=6.8 Hz), 1.45 (9H, s), 2.94-3.10 (1H, br s), 3.19-3.28 (1H, br s), 3.42-3.47 (1H, m), 4.01-4.05 (2H, m), 4.23-4.25 (1H, br s), 4.48-4.50 (1H, br s), 7.24-7.27 (2H, m), 7.44-7.46 (1H, m), 7.53-7.55 (1H, m), 7.75-7.76 (1H, m) MS(ESI) m/z: 434(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(b) (74 mg) was dissolved in dichloromethane (1.4 mL) and trifluoroacetic acid (0.7 mL), and the resulting mixture was stirred at room temperature for 1 hour. The reaction solvent was distilled off under reduced pressure, then ethyl acetate was added thereto, and the resulting mixture was washed with an aqueous solution of sodium hydrogencarbonate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure to obtain 45 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.88-2.97 (2H, m), 3.10-3.16 (2H, m), 3.44(1H, dt, J=3.6, 12.8 Hz), 4.00-4.03 (1H, m), 4.43-4.45 (1H, m), 7.23-7.27 (2H, m), 7.43-7.45 (1H, m), 7.54 (1H, d, J=5.2 Hz), 7.76 (1H, d, J=3.2 Hz) MS(ESI) m/z: 334(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that 3-furylboronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(furan-3-yl)benzoxazol-2-yl)-3-methyl piperazine obtained in Example 17(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.87-2.97 (2H, m), 3.09-3.16 (2H, m), 3.40-3.47 (1H, m), 3.98-4.02 (1H, m), 4.41-4.44 (1H, m), 6.83 (1H, dd, J=0.7, 1.7 Hz), 7.14 (1H, d, J=2.0 Hz), 7.21 (1H, d, J=2.0 Hz), 7.54 (1H, d, J=2.0 Hz), 7.97-7.98 (m, 1H) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that 2-thiophene boronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(thiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 18(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.31 (3H, d, J=6.8 Hz), 2.65-2.66 (1H, m), 2.77-2.85 (2H, m), 2.95-2.98 (1H, m), 3.26-3.37 (1H, m), 3.83-3.87 (1H, m), 4.26 (1H, m), 7.22 (1H, dd, J=3.7, 5.1 Hz), 7.25 (1H, d, J=2.0 Hz), 7.37 (1H, d, J=2.0 Hz), 7.73 (1H, dd, J=1.0, 5.1 Hz), 7.79 (1H, dd, J=1.2, 3.9 Hz) MS(ESI) m/z: 334(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that phenylboronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-phenylbenzoxazol-2-yl)-3-methylpiper azine obtained in Example 19(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.8 Hz), 2.83-2.92 (2H, m), 3.06-3.10 (2H, m), 3.34-3.42 (1H, m), 3.94-3.98 (1H, m), 4.36-4.42 (1H, m), 7.18(1H, cl, J=2.0 Hz), 7.28 (1H, d, J=2.2 Hz), 7.43-7.38 (1H, m), 7.51-7.47 (2H, m), 7.73-7.75 (2H, m) MS(ESI) m/z: 328(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (60 mg), cesium carbonate (64 mg, 1.4 equivalents), (S)-Tol BINAP (7 mg, 0.075 equivalents), and pyrrolidine (18 μL, 1.5 equivalents) were dissolved in toluene (1.0 mL), the resulting mixture was stirred in an argon atmosphere for 15 minutes, then tris(dibenzylideneacetone)dipalladium(0) (6.5 mg, 0.05 equivalents) was added thereto, and the resulting mixture was stirred in an oil bath at 80° C. for 21 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=3:1) to obtain 40 mg of the title compound. MS(ESI) m/z: 421(M+H)+ The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyrrolidin-1-yl)benzox azol-2-yl)-3-methylpiperazine obtained in Example 20(a) was used instead of (S)-1-tert-butoxycarbonyl-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.37 (3H, d, J=6.8 Hz), 1.98-2.01 (4H, m), 2.83-2.91 (2H, m), 3.06-3.10 (2H, m), 3.30-3.37 (1H, m), 3.49-3.52 (4H, m), 3.87-3.91 (1H, m), 4.29-4.34 (1H, m), 6.21 (1H, d, J=2.0 Hz), 6.70 (1H, d, J=2.0 Hz) MS(ESI) m/z: 321(M+H)+ The title compound was obtained in a similar manner as in Example 20(a) except that morpholine was used instead of pyrrolidine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(morpholin-1-yl)benzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 21(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.83-2.92 (2H, m), 3.06-3.10 (2H, m), 3.26 (4H, t, J=4.9 Hz), 3.33-3.40 (1H, m), 3.87-3.88 (1H, m), 3.90 (4H, t, J=4.9 Hz), 4.32-4.35 (1H, m), 6.51 (1H, d, J=1.7 Hz), 6.96 (1H, d, J=1.7 Hz) MS(ESI) m/z: 337(M+H)+ The title compound was obtained in a similar manner as in Example 20(a) except that piperidine was used instead of pyrrolidine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(piperidin-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 22(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 1.61-1.65 (2H, m), 1.73-1.78 (4H, m), 2.83-2.91 (2H, m), 3.06-3.10 (2H, m), 3.22 (4H, t, J=5.6 Hz), 3.32-3.39 (1H, m), 3.89-3.93 (1H, m), 4.32-4.38 (1H, m), 6.52 (1H, d, J=1.7 Hz), 6.91 (1H, d, J=1.7 Hz) MS(ESI) m/z: 335(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), potassium carbonate (43 mg, 2.2 equivalents), tetrakis(triphenylphosphine)palladium(0) (8.1 mg, 0.05 equivalents), and 2-furyl boronic acid MIDA ester (47 mg, 1.5 equivalents) were dissolved in toluene (1.6 mL) and ethanol (0.4 mL), water (50 μL) was added thereto, and the resulting mixture was stirred in an oil bath at 80° C. for 2 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 33 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(furan-2-yl)benzoxazol-2-yl)-3-methyl piperazine obtained in Example 23(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.87-2.95 (2H, m), 3.09-3.13 (2H, m), 3.39-3.46 (1H, m), 3.99-4.03 (1H, m), 4.40-4.46 (1H, m), 6.55 (1H, dd, J=1.7, 3.4 Hz), 6.88 (1H, d, J=3.4 Hz), 7.21 (1H, d, J=2.0 Hz), 7.41 (1H, d, J=2.0 Hz), 7.54(114, dd, J=0.7, 1.7 Hz) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar manner as in Example 20(a) except that cyclopentylamine was used instead of pyrrolidine. MS(ESI) m/z: 435(M+H)+ The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(cyclopentylamino)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 24(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 1.51-1.53 (2H, m), 1.64-1.70 (2H, m), 1.75-1.77 (2H, m), 2.05-2.09 (2H, m), 2.82-2.90 (2H, m), 3.05-3.09 (2H, m), 3.31-3.38 (1H, m), 3.91-3.95 (2H, m), 4.35-4.37 (1H, m), 6.36 (1H, d, J=1.7 Hz), 6.73 (1H, d, J=2.0 Hz) MS(ESI) m/z: 335(M+H)+ The title compound was obtained in a similar manner as in Example 20(a) except that diethylamine was used instead of pyrrolidine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-(5-chloro-7-(diethylamino)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 25(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.19 (6H, t, J=7.1 Hz), 1.49 (3H, d, J=6.8 Hz), 3.02-3.09 (1H, m), 3.14-3.17 (1H, m), 3.24-3.28 (1H, m), 3.42-3.47 (5H, m), 3.55-3.63 (1H, m), 4.06-4.10 (1H, m), 4.52-4.58 (1H, m), 6.40 (1H, d, J=1.7 Hz), 6.78 (1H, d, J=2.0 Hz) MS(ESI) m/z: 323(M+H)+ The title compound was obtained in a similar manner as in Example 20(a) except that dimethylamine was used instead of pyrrolidine. MS(ESI) m/z: 395(M+H)+ The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(dimethylamino)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 26(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.6 Hz), 2.83-2.91 (2H, m), 3.00 (6H, s), 3.06-3.10 (2H, m), 3.32-3.39 (1H, m), 3.90-3.94 (1H, m), 4.33-4.36 (1H, m), 6.39 (1H, d, J=2.0 Hz), 6.85 (1H, d, J=2.0 Hz) MS(ESI) m/z: 295(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), tripotassium phosphate (103 mg, 3.5 equivalents), tricyclohexylphosphine (3.9 mg, 0.1 equivalents), palladium acetate (II) (1.6 mg, 0.05 equivalents), and cyclopropyl boronic acid (16 mg, 1.3 equivalents) were dissolved in toluene (1.0 mL), water was added thereto (50 μL), and the resulting mixture was stirred in an oil bath at 80° C. for 15 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=4:1) to obtain 34 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-cyclopropylbenzoxazol-2-yl)-3-meth ylpiperazine obtained in Example 27(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.86-0.91 (2H, m), 1.00-1.05 (2H, m), 1.39 (3H, d, J=6.8 Hz), 2.02-2.09 (1H, m), 2.84-2.92 (2H, m), 3.06-3.11 (2H, m), 3.33-3.40 (1H, m), 3.94-3.98 (1H, m), 4.35-4.41 (1H, m), 6.57 (1H, d, J=2.0 Hz), 7.10 (1H, d, J=2.0 Hz) MS(ESI) m/z: 292(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), cesium carbonate (68 mg, 1.5 equivalents), RockPhos (3.9 mg, 0.06 equivalents), allylpalladium(II)chloride (dimer) (2.6 mg, 0.05 equivalents), and cyclopentyl alcohol (25 μL, 2.0 equivalents) were dissolved in triethylamine (1.0 mL), and the resulting mixture was stirred in an oil bath at 60 to 90° C. for 18 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was roughly purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=3:2) to obtain 10.4 mg of the title compound. 2.2 mg of the title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(cyclopentyloxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 28(a) (10.4 mg) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 1.64-1.92 (8H, m), 2.85-2.94 (2H, m), 3.07-3.13 (2H, m), 3.34-3.40 (1H, m), 3.97-4.00 (1H, m), 4.41 (1H, m), 4.89-4.91 (1H, m), 6.58 (1H, d, J=1.7 Hz), 6.94 (1H, d, J=2.0 Hz) MS(ESI) m/z: 336(M+H)+ The title compound was obtained in a similar manner as in Example 28(a) except that ethanol was used instead of cyclopentyl alcohol. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-ethoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 29(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 1.47 (3H, t, J=7.1 Hz), 2.82-2.90 (2H, m), 3.05-3.09 (2H, m), 3.32-3.39 (1H, m), 3.96-4.00 (1H, m), 4.19(2H, q, J=7.1 Hz), 4.37-4.43 (1H, m), 6.59 (1H, d, J=2.0 Hz), 6.95 (1H, d, J=1.7 Hz) MS(ESI) m/z:296(M+H)+ The title compound was obtained in a similar manner as in Example 28(a) except that 1-propanol was used instead of cyclopentyl alcohol. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-n-propoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 30(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.06 (3H, t, J=7.6 Hz), 1.39 (3H, d, J=6.8 Hz), 1.81-1.90 (2H, m), 2.83-2.91 (2H, m), 3.05-3.09 (2H, m), 3.32-3.39 (1H, m), 3.94-4.02 (1H, m), 4.08 (2H, t, J=6.6 Hz), 4.37-4.43 (1H, m), 6.60(1H, d, J=1.7 Hz), 6.95 (1H, d, J=1.7 Hz) MS(ESI) m/z: 310(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), tris-tert-butylphosphine (a 1 M solution in toluene, 14 μL, 0.1 equivalents), tris(dibenzylideneacetone)dipalladium(0) (6.4 mg, 0.05 equivalents), and cyclopentyl zinc bromide (a 0.5 M solution in toluene, 560 μL, 2.0 equivalents) were dissolved in toluene (0.5 mL), and the resulting mixture was stirred in an oil bath at 50° C. for 17.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 28 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-cyclopentylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 31(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.6 Hz), 1.67-1.85 (6H, m), 2.07-2.13 (2H, m), 2.84-2.92 (2H, m), 3.07-3.11 (2H, m), 3.18-3.23 (1H, m), 3.32-3.39 (1H, m), 3.93-3.96 (1H, m), 4.35-4.38 (1H, m), 6.85 (1H, d, J=2.0 Hz), 7.14 (1H, d, J=2.2 Hz) MS(ESI) m/z: 320(M+H)+ The title compound was obtained in a similar manner as in Example 31(a) except that n-butyl zinc bromide (a 0.5 M solution in THF) was used instead of cyclopentyl zinc bromide (a 0.5 M solution in toluene). The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(7-n-butyl-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 32(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.95 (3H, t, J=7.3 Hz), 1.34-1.38 (2H, m), 1.41 (3H, d, J=6.8 Hz), 1.63-1.70 (2H, m), 2.72 (2H, t, J=7.6 Hz), 2.87-2.96 (2H, m), 3.10-3.15 (2H, m), 3.36-3.43 (1H, m), 3.97-4.00 (1H, m), 4.38-4.44 (1H, m), 6.82 (1H, d, J=2.2 Hz), 7.15 (1H, d, J=2.2 Hz) MS(ESI) m/z: 308(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), pyrazole (19 mg, 2.0 equivalents), copper(I) iodide (27 mg, 1.0 equivalent), and cesium carbonate (137 mg, 3.0 equivalents) were dissolved in DMF (1.0 mL), and the reaction was performed by using a microwave reactor at 150° C. for 2 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=10:3) to obtain 38 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 33(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.40-3.47 (1H, m), 3.97-4.01 (1H, m), 4.38-4.44 (1H, m), 6.53 (1H, dd, J=0.7, 1.7 Hz), 7.21 (1H, d, J=2.2 Hz), 7.62 (1H, d, J=2.0 Hz), 7.77 (1H, d, J=2.0 Hz), 8.18 (1H, dd, J=0.5, 2.0 Hz) MS(ESI) m/z:318(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (60 mg), tetrakis(triphenylphosphine)palladium(0) (8.1 mg, 0.05 equivalents), and 2-(tributylstannyl)oxazole (44 μL 1.5 equivalents) were dissolved in DMF (1.0 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 90° C. for 3 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=7:3) to obtain 30.1 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(oxazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 34(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95(2H, in), 3.09-3.13 (2H, m), 3.40-3.47 (1H, m), 4.06-4.09 (1H, m), 4.46-4.52 (1H, m), 7.33 (1H, d, J=0.7 Hz), 7.36 (1H, d, J=2.0 Hz), 7.65 (1H, d, J=2.0 Hz), 7.80 (1H, d, J=0.7 Hz) MS(ESI) m/z: 319(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 35(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.8 Hz), 2.88-2.97 (2H, m), 3.11-3.15 (2H, m), 3.42-3.49 (1H, m), 4.05-4.08 (1H, m), 4.45-4.50 (1H, m), 7.34 (1H, d, J=2.2 Hz), 7.49 (1H, d, J=3.2 Hz), 7.84 (1H, d, J=2.0 Hz), 7.97 (1H, d, J=3.2 Hz) MS(ESI) m/z: 335(M+H)+ The title compound was obtained in a similar manner as in Example 33(a) except that imidazole was used instead of pyrazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-imidazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 36(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.31 (3H, d, J=6.8 Hz), 2.77-2.97 (3H, m), 3.24-3.27 (2H, m), 3.79-3.86 (1H, m), 4.26 (1H, m), 7.17 (1H, s), 7.30-7.34 (1H, m), 7.44-7.47 (1H, m), 7.87-7.88 (1H, m), 8.36 (1H, s) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 4-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-4-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 37(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.88-2.96 (2H, m), 3.10-3.14 (2H, m), 3.41-3.48 (1H, m), 4.00-4.04 (1H, m), 4.41-4.48 (1H, m), 7.30 (1H, d, J=2.0 Hz), 7.86 (1H, d, J=2.0 Hz), 7.88 (1H, d, J=2.0 Hz), 8.92 (1H, d, J=2.0 Hz) MS(ESI) m/z: 335(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 5-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-5-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 38(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.96 (2H, m), 3.09-3.14 (2H, m), 3.40-3.47 (1H, m), 4.00-4.04 (1H, m), 4.41-4.47 (1H, m), 7.21 (1H, d, J=2.0 Hz), 7.27 (1H, d, J=2.0 Hz), 8.37 (1H, s), 8.86 (1H, s) MS(ESI) m/z: 335(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (60 mg), tetrakis(triphenylphosphine)palladium(0) (16.2 mg, 0.1 equivalents), and 5-methyl-2-furyl boronic acid pinacol ester (65 μL, 2.25 equivalents) were dissolved in DMF (1.0 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 90° C. for 4.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=4:1) to obtain 51.0 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-methylfuran-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 39(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.41 (3H, s), 2.86-2.95 (2H, m), 3.09-3.13 (2H, m), 3.38-3.45 (1H, m), 3.98-4.01 (1H, m), 4.39-4.45 (1H, m), 6.13-6.14 (1H, m), 6.77 (1H, d, J=3.2 Hz), 7.17 (1H, d, J=2.0 Hz), 7.38 (1H, d, J=2.0 Hz) MS(ESI) m/z: 332(M+H)+ The title compound was obtained in a similar manner as in Example 33(a) except that 4-methylpyrazole was used instead of pyrazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(4-methyl-1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 40(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.20 (3H, s), 2.87-2.96 (2H, m), 3.09-3.15 (2H, m), 3.40-3.47 (1H, m), 3.97-4.01 (1H, m), 4.39-4.45 (1H, m), 7.18 (1H, d, J=2.0 Hz), 7.56 (1H, d, J=2.0 Hz), 7.57 (1H, s), 7.90 (1H, s) MS(ESI) m/z: 332(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 41(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.6 Hz), 2.86-2.95 (2H, m), 3.09-3.13 (2H, m), 3.39-3.46 (1H, m), 3.98-4.02 (1H, m), 4.40-4.46 (1H, m), 7.27-7.31 (1H, m), 7.35 (1H, d, J=2.0 Hz), 7.80-7.84 (2H, m), 7.97-7.99 (1H, m), 7.74-8.76 (1H, m) MS(ESI) m/z: 329(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), 3-pyridyl boronic acid MIDA ester (49 mg, 1.5 equivalents), copper(I) iodide (13.3 mg, 0.5 equivalents), potassium carbonate (39 mg, 2.0 equivalents), tetrakis(triphenylphosphine)palladium(0) (16 mg, 0.1 equivalents), and isopropyl alcohol (300 μL) were dissolved in DMF (1.2 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 100° C. for 22 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=1:1) to obtain 29.5 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-3-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 42(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.47 (3H, d, J=6.8 Hz), 2.92-3.06 (2H, m), 3.15-3.25 (2H, m), 3.47-3.55 (1H, m), 4.05-4.08 (1H, m), 4.49-4.55 (1H, m), 7.20 (1H, d, J=2.0 Hz), 7.34 (1H, d, J=2.2 Hz), 7.44 (1H, dd, J=4.9, 8.1 Hz), 8.00(1H, dt, J=2.4, 7.8 Hz), 8.65 (1H, dd, J=1.7, 4.9 Hz), 9.04 (1H, d, J=2.2 Hz) MS(ESI) m/z: 329(M+H)+ The title compound was obtained in a similar manner as in Example 42(a) except that 4-pyridyl boronic acid MIDA ester was used instead of 3-pyridyl boronic acid MIDA ester. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-4-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 43(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz); 2.88-2.99 (2H, m), 3.10-3.18 (2H, m), 3.42-3.49 (1H, m), 3.98-4.02 (1H, m), 4.41-4.47 (1H, m), 7.24 (1H, d, J=2.2 Hz), 7.36 (1H, d, J=2.0 Hz), 7.66 (2H, d, J=6.1 Hz), 8.73 (2H, d, J=6.1 Hz) MS(ESI) m/z: 329(M+H)+ 58.9 mg of the title compound was obtained in a similar manner as in Example 31(a) except that cyclohexyl zinc bromide (a 0.5 M solution in THF) was used instead of cyclopentyl zinc bromide (a 0.5 M solution in toluene). 4.0 mg of the title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-cyclohexylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 44(a) (58.9 mg) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 1.23-1.92 (10H, m), 2.75-2.82 (1H, m), 2.85-2.93 (2H, m), 3.07-3.12 (2H, m), 3.33-3.40 (1H, m), 3.94-3.97 (1H, m), 4.37-4.39 (1H, m), 6.83 (1H, d, J=2.0 Hz), 7.14 (1H, d, J=2.0 Hz) MS(ESI) in/z: 334(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), tripotassium phosphate (59 mg, 2.0 equivalents), Me4t-butylXPhos (8.1 mg, 0.12 equivalents), tris(dibenzylideneacetone)dipalladium(0) (6.4 mg, 0.05 equivalents), and 1,2,3-triazole (12 μL 1.5 equivalents) were dissolved in toluene (1.0 mL), and the resulting mixture was stirred in an oil bath at 120° C. for 5.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=7:3) to obtain 33 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2H-1,2,3-triazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 45(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.09-3.13 (2H, m), 3.40-3.48 (1H, m), 4.04-4.08 (1H, m), 4.45-4.51 (1H, m), 7.29 (1H, d, J=2.0 Hz), 7.68 (1H, d, J=2.0 Hz), 7.89 (2H, s) MS(ESI) m/z: 319(M+H)+ The title compound was obtained in a similar manner as in Example 45(a) except that 1,2,4-triazole was used instead of 1,2,3-triazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-1,2,4-triazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 46(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.6 Hz), 2.86-2.96 (2H, m), 3.08-3.15 (2H, m), 3.41-3.48 (1H, m), 3.97-4.00 (1H, m), 4.38-4.44 (1H, m), 7.29 (1H, d, J=2.0 Hz), 7.58 (1H, d, J=2.0 Hz), 8.15 (1H, s), 8.83 (1H, s) MS(ESI) m/z: 319(M+H)+ The title compound was obtained in a similar manner as in Example 31(a) except that isobutyl zinc bromide (a 0.5 M solution in THF) was used instead of cyclopentyl zinc bromide (a 0.5 M solution in toluene). The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-isobutylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 47(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.94 (6H, dd, J=3.7, 6.6 Hz), 1.38(3H, d, J 6.8 Hz), 1.95-2.06 (1H, m), 2.59 (2H, d, J=7.1 Hz), 2.84-2.92 (2H, m), 3.07-3.11 (2H, m), 3.32-3.39 (1H, m), 3.93-3.96 (1H, m), 4.34-4.39 (1H, m), 6.78 (1H, d, J=2.0 Hz), 7.15 (1H, d, J=2.0 Hz) MS(ESI) m/z: 308(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that o-hydroxymethylphenyl boronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2-hydroxymethylphenyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 48(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.8 Hz), 2.88-3.01 (2H, m), 3.11-3.20 (2H, m), 3.41-3.48 (1H, m), 3.96-3.99 (1H, m), 4.42-4.45 (1H, m), 4.60 (2H, s), 6.99 (1H, d, J=2.2 Hz), 7.32-7.35 (2H, m), 7.40 (1H, t, J=7.6 Hz), 7.46-7.50 (1H, m), 7.66 (1H, d, J=7.6 Hz) MS(ESI) m/z: 358(M+H)+ N-Methylimidazole (44 μL, 1.0 mmol) was dissolved in diethyl ether (1.0 mL), then resulting mixture was cooled to −78° C., and n-butyllithium (a 2.77 M solution in hexane, 542 μL, 1.5 mmol) was added thereto, and the resulting mixture was stirred for 1 hour in this state. Tributylstannyl chloride (405 μL, 1.5 mmol) was added to the reaction mixture, the temperature of the reaction mixture was gradually raised, and the mixture was further stirred at room temperature for 1 hour. The precipitate was removed from the reaction system, then the solvent was distilled off from the reaction mixture under reduced pressure, the residue was dissolved in DMF (1.0 mL), (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg, 0.14 mmol) and tetrakis(triphenylphosphine)palladium(0) (16.2 mg, 0.014 mmol) were added thereto, and the resulting mixture was stirred in an argon atmosphere in an oil bath at 120° C. for 14 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=1:1) to obtain 54.3 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1-methyl-1H-imidazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 49(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.40 (3H, d, J=6.8 Hz), 2.83-2.94 (2H, m), 3.06-3.13 (2H, m), 3.36-3.43 (1H, m), 3.71 (3H, s), 3.94-3.98 (1H, m), 4.37-4.43 (1H, m), 7.05 (1H, d, J=1.2 Hz), 7.20 (1H, d, J=2.0 Hz), 7.20 (1H, d, J=1.2 Hz), 7.36 (1H, d, J=2.0 Hz) MS(ESI) m/z: 332(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (860 mg, 2.0 mmol), bis(pinacolato)diboron (762 mg, 1.5 equivalents), potassium acetate (589 mg, 3.0 equivalents), and [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct (163 mg, 0.01 equivalents) were dissolved in 1,4-dioxane (10 mL), and the resulting mixture was stirred in an oil bath at 90° C. for 2 hours. The solvent was distilled off from the reaction mixture under reduced pressure, a small amount of ethyl acetate was added to the residue, insoluble matter was removed, and then the resultant was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 927 mg of the title compound. MS(ESI) m/z: 478(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4,4,5,5-tetramethyl-1,3,2-di oxaboran-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 50(a) (48 mg, 0.1 mmol), 2-bromo-1H-imidazole (29 mg, 2.0 equivalents), tetrakis(triphenylphosphine)palladium(0) (11.6 mg, 0.1 equivalents), and potassium carbonate (55 mg, 4.0 equivalents) were dissolved in 1,4-dioxane (800 μL) and water (200 μL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 110° C. for 4 hours. Water was added to the reaction mixture, the product was extracted with ethyl acetate, and the organic layer was washed with a saturated saline solution. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by preparative TLC (developing solvent, methanol: chloroform=1:19) to obtain 21.3 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-imidazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 50(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.31 (3H, d, J=7.1 Hz), 2.64-2.70 (1H, m), 2.79-2.90 (2H, m), 2.97-3.00 (1H, m), 3.24-3.28 (1H, m), 3.99-4.02 (1H, m), 4.39 (1H, m), 7.15 (1H, s), 7.29 (1H, d, J=2.0 Hz), 7.35 (1H, s), 7.52 (1H, d, J=2.0 Hz), 12.28 (1H, s) MS(ESI) m/z: 318(M+H)+ Methylenecyclohexane (60 μL, 0.5 mmol) was added to 9-BBN (a 0.5 M solution in THF, 2.0 mL, 1.0 mmol), and the resulting mixture was stirred at 80° C. by using a microwave device for 1 hour. A 5 N aqueous solution of sodium hydroxide (0.2 mL, 1.0 mmol) was added to the reaction mixture, then (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg, 0.14 mmol), [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct (11.4 mg, 0.01 equivalents), and potassium carbonate (58 mg, 0.42 mmol) were added thereto, and the resulting mixture was stirred at room temperature for 3 hours. The solvent was distilled off from the reaction mixture under reduced pressure, and the residue was purified by preparative TLC (developing solvent, hexane:ethyl acetate=4:1). (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclohexylmethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 51(a) (the whole amount) was dissolved in chloroform (0.6 mL) and trifluoroacetic acid (0.3 mL), and the resulting mixture was stirred at room temperature for 1.5 hours. The reaction solvent was distilled off under reduced pressure, then ethyl acetate was added thereto, and the resulting mixture was sequentially washed with an aqueous solution of sodium hydrogencarbonate and a saturated saline solution. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, methanol:chloroform=2:98) to obtain 2.7 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 0.95-1.02 (2H, m), 1.09-1.23 (2H, m), 1.50 (3H, d, J=7.1 Hz), 1.61-1.69 (4H, m), 1.87-2.00 (3H, m), 2.60 (2H, d, J=6.8 Hz), 3.02-3.09 (1H, m), 3.14-3.28 (2H, m), 3.34-3.38 (1H, m), 3.55-3.63 (1H, m), 4.11-4.16 (1H, m), 4.58-4.61 (1H, m), 6.83 (1H, d, J=2.0 Hz), 7.17(1H, d, J=2.0 Hz) MS(ESI) m/z: 348(M+H)+ The title compound was obtained in a similar manner as in Example 28(a) except that water was used instead of cyclopentyl alcohol. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-hydroxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 52(a) (49 mg, 0.14 mmol), cethyltrimethyl ammonium bromide (5.1 mg, 0.1 equivalents), bromocyclohexane (34 μL 2.0 equivalents), and potassium hydroxide (24 mg, 3.0 equivalents) were dissolved in 1,4-dioxane (0.5 mL), the resulting mixture was stirred in an oil bath at 100° C. for 14 hours, then acetyltrimethyl ammonium bromide (20 mg, 0.4 equivalents), bromocyclohexane (51 μL, 3.0 equivalents), and potassium hydroxide (24 mg, 3.0 equivalents) were further added, and the resulting mixture was continuously stirred for 2 hours. A saturated saline solution was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was washed with a saturated saline solution and dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 17.7 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(cyclohexyloxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 52(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.33-1.35 (4H, m), 1.39 (3H, d, J=6.8 Hz), 1.54-1.59 (2H, m), 1.82-1.84 (2H, m), 2.01-2.05 (2H, m), 2.83-2.91 (2H, m), 3.06-3.10 (2H, m), 3.32-3.39 (1H, m), 3.94-3.98 (1H, m), 4.40-4.34 (2H, m), 6.61 (1H, d, J=2.0 Hz), 6.95 (1H, d, J=2.0 Hz) MS(ESI) m/z: 350(M+H)+ The title compound was obtained in a similar manner as in Example 52(b) except that bromomethylcyclopropane was used instead of bromocyclohexane. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(cyclopropylmethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 53(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 0.40-0.36 (2H, m), 0.65-0.69 (2H, m), 1.26-1.36 (1H, m), 1.39 (3H, d, J=6.8 Hz), 2.82-2.90 (2H, m), 3.05-3.09 (2H, m), 3.32-3.40 (1H, m), 3.95 (2H, d, J=7.1 Hz), 3.96-4.00 (1H, m), 4.39-4.42 (1H, m), 6.58 (1H, d, J=1.7 Hz), 6.95 (1H, d, J=2.0 Hz) MS(ESI) m/z: 322(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 3-bromoisothiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(isothiazole-3-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 54(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.88-2.96 (2H, m), 3.10-3.15 (2H, m), 3.41-3.48 (1H, m), 4.01-4.04 (1H, m), 4.42-4.48 (1H, m), 7.34 (1H, d, J=2.0 Hz), 7.78 (1H, d, J=2.0 Hz), 7.84 (1H, d, J=4.9 Hz), 8.80 (1H, d, J=4.9 Hz) MS(ESI) m/z: 335(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromothiazole-5-methanol was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-hydroxymethylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 55(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.36 (3H, d, J=6.6 Hz), 2.66-2.73 (1H, m), 2.82-2.92 (2H, m), 3.00-3.03 (1H, m), 3.38 (1H, m), 3.87-3.90 (1H, m), 4.29-4.31 (1H, m), 4.78 (2H, d, J=5.4 Hz), 5.71 (1H, t, J=5.6 Hz), 7.41 (1H, d, J=2.0 Hz), 7.66 (1H, d, J=2.2 Hz), 7.87 (1H, s) MS(ESI) m/z: 365(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 2-(tributylstannyl)pyrimidine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyrimidin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 56(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.8 Hz), 2.86-2.93 (2H, m), 3.09-3.13 (2H, m), 3.40-3.47 (1H, m), 4.05-4.08 (1H, m), 4.45-4.51 (1H, m), 7.26 (1H, t, J=4.9 Hz), 7.41 (1H, d, J=2.2 Hz), 7.95 (1H, d, J=2.2 Hz), 8.88 (2H, d, J=4.9 Hz) MS(ESI) m/z: 330(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that 5-chloro-2-thiophene boronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-chlorothiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 57(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.91-3.02 (2H, m), 3.13-3.22 (2H, m), 3.44-3.52 (1H, m), 4.04-4.07 (1H, m), 4.45-4.51 (1H, m), 6.97 (1H, d, J=3.9 Hz), 7.17 (1H, d, J=2.0 Hz), 7.22 (1H, d, J=2.0 Hz), 7.32 (1H, d, J=3.9 Hz) MS(ESI) m/z: 368(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 5-chloro-2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-chloropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 58(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.87-2.95 (2H, m), 3.09-3.13 (2H, m), 3.39-3.47 (1H, m), 3.98-4.00 (1H, m), 4.39-4.45 (1H, m), 7.35 (1H, d, J=2.2 Hz), 7.78-7.81 (2H, m), 7.94 (1H, d, J=8.3 Hz), 8.69 (1H, d, J=2.4 Hz) MS(ESI) m/z: 363(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 4-chloro-2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(4-chloropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 59(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=6.5 Hz), 2.88-2.96 (2H, m), 3.10-3.15 (2H, m), 3.42-3.47 (1H, m), 3.97-4.00 (1H, m), 4.40-4.45 (1H, m), 7.30 (1H, dd, J=2.0, 5.5 Hz), 7.36 (1H, d, J=2.0 Hz), 7.82 (1H, d, J=2.0 Hz), 8.01 (1H, d, J=2.0 Hz), 8.64 (1H, d, J=5.0 Hz) MS(ESI) m/z: 363(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 6-fluoro-2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(6-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 60(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.87-2.96 (2H, m), 3.10-3.14 (2H, m), 3.41-3.48 (1H, m), 3.99-4.02 (1H, m), 4.41-4.47 (1H, m), 6.92-6.95 (1H, m), 7.36 (1H, d, J=2.2 Hz), 7.84 (1H, d, J=2.0 Hz), 7.89-7.95 (2H, m) MS(ESI) m/z: 347(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 3-fluoro-2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(3-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 61(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.83-2.91 (2H, m), 3.06-3.10 (2H, m), 3.33-3.40 (1H, m), 3.93-3.96 (1H, m), 4.34-4.40 (1H, m), 7.36-7.40 (3H, m), 7.53-7.58 (1H, m), 8.57-8.59 (1H, m) MS(ESI) m/z: 347(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-cyanothiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-cyanothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 62(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.36 (3H, d, J=6.8 Hz), 2.67-2.72 (1H, m), 2.88-2.92 (2H, m), 3.02-3.05 (1H, m), 3.37-3.40 (1H, m), 3.94-3.97 (1H, m), 4.37 (1H, m), 7.56 (1H, d, J=2.2 Hz), 7.74 (1H, d, J=2.2 Hz), 8.88 (1H, s) MS(ESI) m/z: 360(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-methylthiazol was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-methylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 63(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.58 (3H, s), 2.89-2.99 (2H, m), 3.12-3.18 (2H, m), 3.43-3.50 (1H, m), 4.05-4.08 (1H, m), 4.45-4.52 (1H, m), 7.31 (1H, d, J=2.2 Hz), 7.60 (1H, s), 7.77 (1H, d, J=2.0 Hz) MS(ESI) m/z: 349(M+H)+ The title compound was obtained in a similar manner as in Example 16(b) except that 2-chloro-3-thiophene boronic acid was used instead of 3-thiophene boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2-chlorothiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 64(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.82-2.91 (2H, m), 3.05-3.09 (2H, m), 3.32-3.40 (1H, m), 3.93-3.96 (1H, m), 4.34-4.40 (1H, m), 7.14 (1H, d, J=5.6 Hz), 7.17 (1H, d, J=2.0 Hz), 7.21 (1H, d, J=5.9 Hz), 7.30 (1H, d, J=2.0 Hz) MS(ESI) m/z: 368(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-carbamoylthiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-carbamoylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 65(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.36 (3H, d, J=6.8 Hz), 2.68-2.74 (1H, m), 2.84-2.94 (2H, m), 3.03-3.05 (1H, m), 3.37-3.40 (1H, m), 3.88-3.94 (1H, m), 4.29-4.35 (1H, m), 7.48 (1H, s), 7.71 (1H, s), 7.79 (1H, br s), 8.29 (1H, br s), 8.55 (1H, s) MS(ESI) m/z: 378(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-3-cyanopyridine was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(3-cyanopyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 66(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.8 Hz), 2.84-2.90 (2H, m), 3.06-3.10(2H, in), 3.35-3.43 (1H, m), 3.95-3.99 (1H, m), 4.37-4.43 (1H, m), 7.35 (1H, d, J=2.2 Hz), 7.43 (1H, d, J=2.2 Hz), 7.48 (1H, dd, J=4.9, 8.1 Hz), 8.14 (1H, d, J=7.8 Hz), 8.95 (1H, d, J=4.9 Hz) MS(ESI) m/z: 354(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (48 mg), potassium carbonate (69 mg, 5.0 equivalents), tetrakis(triphenylphosphine)palladium(0) (12 mg, 0.1 equivalents), and 2-fluoro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl)thiophene (46 mg, 2.0 equivalents) were dissolved in 1,4-dioxane (0.8 mL) and water (0.2 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 100° C. for 4 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 21.8 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-fluorothiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 67(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.96 (2H, m), 3.09-3.14 (2H, m), 3.38-3.46 (1H, m), 3.98-4.02 (1H, m), 4.39-4.45 (1H, m), 6.53 (1H, dd, J=2.0, 4.2 Hz), 7.12 (1H, d, J=2.0 Hz), 7.17 (1H, t, J=3.9 Hz), 7.20 (1H, d, J=2.0 Hz) MS(ESI) m/z: 352(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 3-methyl-2-pyridyl zinc bromide was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(3-methylpyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 68(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.36 (3H, d, J=6.8 Hz), 2.30 (3H, s), 2.79-2.88 (2H, m), 3.02-3.06 (2H, m), 3.29-3.36 (1H, m), 3.86-3.89 (1H, m), 4.29-4.35 (1H, m), 7.11 (1H, d, J=2.0 Hz), 7.26-7.28 (1H, m), 7.35 (1H, d, J=2.0 Hz), 7.64 (1H, d, J=7.8 Hz), 8.57 (1H, d, J=4.9 Hz) MS(ESI) m/z: 343(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 4-bromo-2-methylthiazol was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2-methylthiazol-4-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 69(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.80 (3H, s), 2.88-2.96 (2H, m), 3.10-3.14 (2H, m), 3.40-3.47 (1H, m), 3.99-4.02 (1H, m), 4.41-4.47 (1H, m), 7.27 (1H, s), 7.66 (1H, s), 7.81 (1H, s) MS(ESI) m/z: 349(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (60 mg), tripotassium phosphate (59 mg, 2.0 equivalents), Me4t-butyl XPhos (4.8 mg, 0.01 equivalents), palladium(II) acetate (3.1 mg, 0.1 equivalents), and phenol (20 mg, 1.5 equivalents) were dissolved in toluene (1.0 mL), and the resulting mixture was stirred in an oil bath at 110° C. for 2 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 19 mg of the title compound. 7.9 mg of the title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-phenoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 70(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.35 (3H, d, J=6.8 Hz), 2.79-2.88 (2H, m), 3.02-3.06 (2H, m), 3.29-3.36 (2H, m), 3.88-3.92 (1H, m), 4.27-4.33 (1H, m), 6.60 (1H, d, J=1.7 Hz), 7.06-7.09 (3H, m), 7.14-7.18 (1H, m), 7.35-7.39 (2H, m) MS(ESI) m/z: 344(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (60 mg), cesium carbonate (91 mg, 2.0 equivalents), XantPhos (12.1 mg, 0.15 equivalents), tris(dibenzylideneacetone)dipalladium(0) (12.8 mg, 0.1 equivalents), and 2-pyrrolidone (54 μL, 5.0 equivalents) were dissolved in DMF (1.0 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 120° C. for 16.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=1:1) to obtain 48.7 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2-oxo-pyrrolidin-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 71(a) was used instead of (S)-1-tert-butoxycarbonyl-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 2.21-2.28 (2H, m), 2.61 (2H, t, J=8.3 Hz), 2.83-2.91 (2H, m), 3.06-3.10 (2H, m), 3.33-3.40 (1H, m), 3.90-3.98 (3H, m), 4.32-4.38 (1H, m), 7.16 (1H, d, J=2.0 Hz), 7.21(1H, d, J=2.0 Hz) MS(ESI) m/z: 335(M+H)+ The title compound was obtained in a similar manner as in Example 71(a) except that 2-oxazolidinone was used instead of 2-pyrrolidone. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(2-oxo-oxazolidin-3-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 72(a) was used instead of (S)-1-tert-butoxycarbonyl-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 2.83-2.92 (2H, m), 3.06-3.10 (2H, m), 3.34-3.41 (1H, m), 3.91-3.94 (1H, m), 4.19-4.23 (2H, m), 4.32-4.38 (1H, m), 4.55 (2H, t, J=8.1 Hz), 7.16 (1H, d, J=2.0 Hz), 7.28 (1H, d, J=2.0 Hz) MS(ESI) m/z: 337(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-fluoropyridine was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 73(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.09-3.13 (2H, m), 3.39-3.46 (1H, m), 3.97-4.01 (1H, m), 4.39-4.45 (1H, m), 7.34 (1H, d, J=2.0 Hz), 7.53(1H, dt, J=2.9, 8.8 Hz), 7.77 (1H, d, J=2.2 Hz), 7.99 (1H, dd, J=4.4, 8.8 Hz), 8.60 (1H, d, J=2.9 Hz) MS(ESI) m/z: 347(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-chlorothiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-chlorothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 74(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.88-2.98 (2H, m), 3.10-3.17 (2H, m), 3.42-3.49 (1H, m), 4.02-4.06 (1H, m), 4.43-4.49 (1H, m), 7.34 (1H, d, J=2.0 Hz), 7.73 (1H, s), 7.75 (1H, d, J=2.0 Hz) MS(ESI) m/z: 369(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (60 mg), sodium carbonate (30 mg, 2.0 equivalents), RuPhos (6.5 mg, 0.1 equivalents), palladium(II) acetate (11.6 mg, 0.05 equivalents), and benzyl trifluoro boronic acid potassium (5.6 mg, 2.0 equivalents) were dissolved in ethanol (1.0 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 85° C. for 4.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 41.4 mg of the title compound. 5.5 mg of the title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(7-benzyl-5-chloro-benzoxazol-2-yl)-3-methylpiperazine obtained in Example 75(a) was used instead of (S)-1-tert-butoxycarbonyl-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.35 (3H, d, J=6.8 Hz), 2.81-2.91 (2H, m), 3.04-3.08 (2H, m), 3.29-3.36 (1H, m), 3.89-3.93 (1H, m), 4.06 (2H, s), 4.29-4.35 (1H, m), 6.78 (1H, d, J=2.0 Hz), 7.16 (1H, d, J=2.2 Hz), 7.20-7.31 (5H, m) MS(ESI) m/z: 342(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 4-bromo-5-hydroxymethylthiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that the whole amount of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-(hydroxymethyl)thiazol-4-yl)benz oxazol-2-yl)-3-methylpiperazine obtained in Example 76(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.6 Hz), 2.81-2.90 (2H, m), 3.04-3.08 (2H, m), 3.32-3.40 (1H, m), 3.91-3.93 (1H, m), 4.32-4.39 (1H, m), 4.93 (2H, s), 7.22 (1H, d, J=2.0 Hz), 7.33 (1H, d, J=2.0 Hz), 8.87 (1H, s) MS(ESI) m/z: 365(M+H)+ The title compound was obtained in a similar manner as in Example 70(a) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-hydroxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 28(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine and that 2-bromothiazole was used instead of phenol. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yloxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 77(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.36 (3H, d, J=6.8 Hz), 2.80-2.89 (2H, m), 3.03-3.08 (2H, m), 3.30-3.37 (1H, m), 3.89-3.92 (1H, m), 4.29-4.35 (1H, m), 6.88 (1H, d, J=3.9 Hz), 7.01 (1H, d, J=1.7 Hz), 7.19 (1H, d, J=2.0 Hz), 7.25 (1H, d, J=3.9 Hz) MS(ESI) 351(M+H)+ The title compound was obtained in a similar manner as in Example 50(b) except that 2-bromo-5-nitrothiazole was used instead of 2-bromo-1H-imidazole. The title compound was obtained in a similar manner as in Example 16(c) except that the whole amount of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(5-nitrothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 78(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.48 (3H, d, J=6.8 Hz), 2.90-3.01 (2H, m), 3.12-3.21 (2H, m), 3.46-3.53 (1H, m), 4.05-4.07 (1H, m), 4.46-4.51 (1H, m), 7.44 (1H, d, J=2.0 Hz), 7.88 (1H, d, J=2.0 Hz), 8.66 (1H, s) MS(ESI) m/z: 380(M+H)+ The title compound was obtained in a similar manner as in Example 34(a) except that 2-(tributylstannyl)-3-methoxypyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(3-methoxypyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 79(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.8 Hz), 2.86-2.97 (2H, m), 3.08-3.15 (2H, m), 3.38-3.44 (1H, m), 3.87 (3H, s), 3.96-3.99 (1H, m), 4.39-4.45 (1H, m), 7.30-7.31 (1H, m), 7.33-7.35 (3H, m), 8.33-8.35 (1H, m) MS(ESI) m/z: 359(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (430 mg) and magnesium (26.7 mg, 1.1 equivalents) were dissolved in THF (2.0 mL), and the resulting mixture was stirred in an argon atmosphere in an oil bath at 40° C. for 1 hour. The temperature of the resulting mixture was raised to 60° C., a small amount of iodine and zinc bromide (157 mg, 0.6 equivalents) were added thereto, the resulting mixture was stirred, then 2-(phenylsulfonyl)tetrahydrofuran was added, and the resulting mixture was further stirred at room temperature for 16 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=4:1) to obtain 19.1 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (3 S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(tetrahydrofuran-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 80(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.6 Hz), 1.90-2.09 (3H, m), 2.36-2.43 (1H, m), 2.84-2.92 (2H, m), 3.06-3.10 (2H, m), 3.33-3.40 (1H, m), 3.93-4.00 (2H, m), 4.09-4.15 (1H, m), 4.34-4.40 (1H, m), 5.11-5.15 (1H, m), 7.02-7.03 (1H, m), 7.20(111, d, J=2.2 Hz) MS(ESI) m/z: 322(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (86 mg), potassium carbonate (55.3 mg, 2.0 equivalents), and 2,4,6-tris(4-fluorophenyl)boroxine (73 mg, 1.0 equivalent) were dissolved in THF (1.6 mL) and ethanol (0.4 mL), the resulting mixture was stirred in an argon atmosphere for 15 minutes, then tetrakis(triphenylphosphine)palladium(0) (23 mg, 0.1 equivalents) was added thereto, and the resulting mixture was stirred in an oil bath at 90° C. for 14.5 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=17:3) to obtain 94.6 mg of the title compound. 63.4 mg of the title compound was obtained in a similar manner as in Example 16(c) except that the whole amount of the (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(4-fluorophenyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 81(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.6 Hz), 2.83-2.93 (2H, m), 3.06-3.10 (2H, m), 3.35-3.42 (1H, m), 3.93-3.97 (1H, m), 4.35-4.41 (1H, m), 7.12 (1H, d, J=2.0 Hz), 7.18 (2H, t, J=8.8 Hz), 7.27 (1H, d, J=2.0 Hz), 7.70 (2H, dd, J=5.4, 9.0 Hz) MS(ESI) m/z: 346(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethyl)benzoxazole obtained in Reference Example 10 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 41(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 82(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 82(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.6 Hz), 2.86-2.96 (2H, m), 3.09-3.14 (2H, m), 3.42-3.50 (1H, m), 4.06-4.10 (1H, m), 4.46-4.52 (1H, m), 7.32-7.36 (1H, m), 7.83-7.87 (1H, m), 7.94 (1H, s), 7.99-8.01 (1H, m), 8.77-8.79 (1H, m) MS(ESI) m/z: 397(M+H)+ The title compound was obtained in a similar manner as in Example 45(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 82(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine and that pyrazole was used instead of 1,2,3-triazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 83(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.6 Hz), 2.86-2.96 (2H, m), 3.09-3.15 (2H, m), 3.43-3.51 (1H, m), 4.05-4.09 (1H, m), 4.46-4.49 (1H, m), 6.57 (1H, t, J=2.4 Hz), 7.79 (1H, s), 7.80 (1H, d, J=2.0 Hz), 8.23 (1H, d, J=2.7 Hz) MS(ESI) m/z: 386(M+H)+ The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 84(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.47 (3H, d, J=6.6 Hz), 2.88-2.97 (2H, m), 3.11-3.16 (2H, m), 3.45-3.52 (1H, m), 4.13-4.16 (1H, m), 4.51-4.57 (1H, m), 7.56 (1H, d, J=3.2 Hz), 7.96 (1H, s), 8.01 (1H, d, J=3.2 Hz) MS(ESI) m/z: 403(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-6-(trifluoromethyl)benzoxazole obtained in Reference Example 11 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 41(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 85(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that the whole amount of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 85(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.33 (3H, d, J=6.8 Hz), 2.74-2.86 (2H, m), 2.98-3.02 (2H, m), 3.25-3.32 (1H, m), 3.75-3.78 (1H, m), 4.22-4.30 (1H, m), 7.34-7.40 (2H, m), 7.45 (1H, s), 7.78-7.82 (1H, m), 8.71-8.72 (1H, m) MS(ESI) m/z: 397(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 12 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 41(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 86(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 86(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.87-2.95 (2H, m), 3.09-3.13 (2H, m), 3.40-3.48 (1H, m), 4.03-4.07 (1H, m), 4.44-4.50 (1H, m), 7.29-7.32 (1H, m), 7.81-7.85 (1H, m), 7.93 (1H, s), 7.95-7.97 (1H, m), 8.74-8.76 (1H, m) MS(ESI) m/z: 413(M+H)+ The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 86(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 87(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.86-2.97 (2H, m), 3.10-3.15 (2H, m), 3.43-3.50 (1H, m), 4.09-4.12 (1H, m), 4.49-4.55 (1H, m), 7.51 (1H, d, J=3.2 Hz), 7.94 (1H, s), 7.97 (1H, d, J=3.4 Hz) MS(ESI) m/z: 419(M+H)+ The title compound was obtained in a similar manner as in Example 83(a) except that (S)-1-tert-butoxycathonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 86(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 88(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44(314, d, J=6.8 Hz), 2.87-2.96 (2H, m), 3.08-3.14 (2H, m), 3.41-3.49 (1H, m), 4.02-4.05 (1H, m), 4.43-4.49 (1H, m), 6.54 (1H, t, J=2.4 Hz), 7.71 (1H, s), 7.77 (1H, d, J=1.7 Hz), 8.16 (1H, d, J=2.7 Hz) MS(ESI) m/z: 402(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-4,5-difluoro-2-mercaptobenzoxazole obtained in Reference Example 13 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 41(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-4,5-difluorobenzoxazol-2-yl)-3-methyl piperazine obtained in Example 89(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(4,5-difluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 89(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.87-2.95 (2H, m), 3.09-3.14 (2H, m), 3.41-3.47 (1H, m), 4.02-4.06 (1H, m), 4.47-4.49 (1H, m), 7.26-7.30 (1H, m), 7.70 (1H, dd, J=7.4, 12.6 Hz), 7.79-7.83 (1H, m), 7.94-7.96(1H, m), 8.72-8.74(1H, m) MS(ESI) m/z: 331(M+H)+ (S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-4,5-difluorobenzoxazol-2-yl)-3-methyl piperazine obtained in Example 89(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(4,5-difluoro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 90(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.89-2.96 (2H, m), 3.10-3.15 (2H, m), 3.44-3.49 (1H, m), 4.08-4.11 (1H, m), 4.51-4.53 (1H, m), 7.47 (1H, dd, J=3.2 Hz), 7.67 (1H, dd, J=7.2, 12.0 Hz), 7.94 (1H, d, J=3.2 Hz) MS(ESI) m/z: 337(M+H)+ The title compound was obtained in a similar manner as in Example 83(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-4,5-difluorobenzoxazol-2-yl)-3-methyl piperazine obtained in Example 89(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(4,5-difluoro-7-(1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 91(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=6.9 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.41-3.47 (1H, m), 4.00-4.03 (1H, m), 4.45-4.47 (1H, m), 6.52 (1H, t, J=2.1 Hz), 7.43 (1H, dd, J=6.6, 12.1 Hz), 7.75 (1H, d, J=1.6 Hz), 8.12 (1H, d, J=2.4 Hz) MS(ESI) m/z: 320(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-6-fluoro-2-mercaptobenzoxazole obtained in Reference Example 14 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 41(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-fluorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 92(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-6-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 92(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.36 (3H, d, J=6.8 Hz), 2.80-2.89 (2H, m), 3.04-3.08 (2H, m), 3.31-3.38 (1H, m), 3.87-3.90 (1H, m), 4.31-4.37 (1H, m), 7.33-7.37 (2H, m), 7.66-7.69 (1H, m), 7.84(1H, dt, J=2.0, 7.8 Hz), 8.78-8.80 (1H, m) MS(ESI) m/z: 347(M+H)+ The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-fluorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 92(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-6-fluoro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 93(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.8 Hz), 2.86-2.94 (2H, m), 3.09-3.13 (2H, m), 3.40-3.47 (1H, m), 4.01-4.05 (1H, m), 4.41-4.47 (1H, m), 7.38 (1H, d, J=6.3 Hz), 7.57 (1H, d, J=3.4 Hz), 8.06 (1H, dd, J=2.0, 3.4 Hz) MS(ESI) m/z: 353(M+H)+ The title compound was obtained in a similar manner as in Example 83(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-fluorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 92(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-6-fluoro-7-(1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 94(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 2.81-2.90 (2H, m), 3.04-3.08 (2H, m), 3.33-3.40 (1H, m), 3.90-3.94 (1H, m), 4.33-4.39 (1H, m), 6.54 (1H, t, J=2.7 Hz), 7.31 (1H, d, J=6.1 Hz), 7.84 (1H, d, J=2.0 Hz), 7.89 (1H, d, J=2.7 Hz) MS(ESI) m/z: 336(M+H)+ The title compound was obtained in a similar manner as in Example 2 except that 5-chloro-2-mercapto-7-propylbenzoxazole obtained in Reference Example 15 was used instead of 5-chloro-7-methoxy-2-mercaptobenzoxazole. 1H-NMR (400 MHz, CDCl3) δ: 0.97 (3H, t, J=7.4 Hz), 1.40 (3H, d, J=6.8 Hz), 1.67-1.76 (2H, m), 2.70 (2H, m), 2.84-2.92 (2H, m), 3.07-3.11 (2H, m), 3.33-3.40 (1H, m), 3.97 (1H, m), 4.39 (1H, m), 6.80 (1H, d, J=2.0 Hz), 7.15 (1H, d, J=2.0 Hz) MS(ESI) m/z: 294(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-carboxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 15(b) (59 mg) was dissolved in DMF (1.5 mL), WSCI (43 mg) and HOBT (30 mg) were added thereto, the resulting mixture was stirred at room temperature for 10 minutes, then dimethylamine (a 2 M solution in THF, 0.275 mL) was added, and the resulting mixture was stirred for 1.5 hours in this state. Water was added, the product was extracted with ethyl acetate, the organic layer was washed with a saturated saline solution and then dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by preparative TLC (developing solvent, chloroform:methanol=9:1) to obtain 66 mg of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-dimethylaminocarbonylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 96(a) (65 mg) was dissolved in dichloromethane (1.5 mL), then trifluoroacetic acid (0.75 mL) was added thereto, and the resulting mixture was stirred at room temperature for 1 hour. A 5% aqueous solution of sodium hydrogencarbonate was added to the reaction mixture, the product was extracted with ethyl acetate, then the organic layer was washed with a saturated saline solution and dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=9:1) to obtain 36 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.82-2.91 (2H, m), 3.00 (3H, s), 3.04-3.10 (2H, m), 3.16 (3H, s), 3.33-3.40 (1H, m), 3.94-3.97 (1H, m), 4.35-4.41 (1H, m), 7.02 (1H, d, J=2.0 Hz), 7.31 (1H, d, J=2.0 Hz) MS(ESI) m/z: 323(M+H)+ The title compound was obtained in a similar manner as in Example 96 except that diethylamine was used instead of dimethylamine 1H-NMR (400 MHz, CDCl3) δ: 1.11 (3H, t, J=7.1 Hz), 1.28 (3H, t, J=7.3 Hz), 1.38 (3H, d, J=6.8 Hz), 2.81-2.91 (2H, m), 3.04-3.09 (2H, m), 3.27(2H, q, J=7.1 Hz), 3.30-3.39 (1H, m), 3.60(2H, q, J=6.8 Hz), 3.92-3.95 (1H, m), 4.33-4.39 (1H, m), 6.95 (1H, d, J=2.0 Hz), 7.29 (1H, d, J=2.0 Hz) MS(ESI) m/z: 351(M+H)+ The title compound was obtained in a similar manner as in Example 96 except that triethylamine and hydroxyamine hydrochloride were used instead of dimethylamine. 1H-NMR (400 MHz, DMSO-d6) δ: 1.31 (3H, d, J=6.8 Hz), 2.66-2.73 (1H, m), 2.84-2.93 (2H, m), 3.01-3.03 (1H, m), 3.25-3.39 (1H, m), 3.88-3.92 (1H, m), 4.32 (1H, m), 7.21 (1H, d, J=2.2 Hz), 7.44 (1H, d, J=2.0 Hz), 9.32 (1H, br s), 11.08 (1H, br s) MS(ESI) m/z: 311(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-carboxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 15(b) (40 mg) was dissolved in dichloromethane (1.0 mL), then trifluoroacetic acid (0.5 mL) was added, and the resulting mixture was stirred at room temperature for 1 hour. Acetone was added to the reaction mixture, the solvent was distilled off under reduced pressure, and the residue was washed with hexane to obtain the title compound as a trifluoroacetate salt. 1H-NMR (400 MHz, DMSO-d6) δ: 1.39 (3H, d, J=7.1 Hz), 2.51 (1H, m), 3.19-3.12 (1H, m), 3.38-3.40 (2H, m), 3.52-3.59 (1H, m), 4.11-4.14 (1H, m), 4.58-4.60 (1H, m), 7.47 (1H, d, J=2.2 Hz), 7.65 (1H, d, J=2.2 Hz) MS(ESI) m/z: 296(M+11)+ The title compound was obtained in a similar manner as in Example 96 except that methylamine was used instead of dimethylamine 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.09 (3H, d, J=4.9 Hz), 3.11-3.15 (2H, m), 3.40-3.47 (1H, m), 3.91-3.95 (1H, m), 4.35-4.41 (1H, m), 6.61(1H, bs), 7.39 (1H, d, J=2.0 Hz), 7.63(1H, d, J 2.2 Hz) MS(ESI) m/z: 309(M+H)+ The title compound was obtained in a similar manner as in Example 96 except that ethylamine was used instead of dimethylamine. 1H-NMR (400 MHz, CDCl3) δ: 1.29 (3H, t, J=7.3 Hz), 1.43 (3H, d, J=6.8 Hz), 2.87-2.96 (2H, m), 3.09-3.15 (2H, m), 3.41-3.48 (1H, m), 3.53-3.60 (2H, m), 3.90-3.94 (1H, m), 4.33-4.39 (1H, m), 6.59 (1H, br s), 7.39 (1H, d, J=2.0 Hz), 7.62 (1H, d, J=2.0 Hz) MS(ESI) m/z: 323(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-fluoro-2-mercaptobenzoxazole obtained in Reference Example 16 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 34(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 102(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine and that 2-(tributylstannyl)pyridine was used instead of 2-(tributylstannyl)oxazole. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 102(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.7 Hz), 2.87-2.96 (2H, m), 3.09-3.15 (2H, m), 3.38-3.49 (1H, m), 3.98-4.04 (1H, m), 4.40-4.50 (1H, m), 7.07-7.11 (1H, m), 7.25-7.28 (1H, m), 7.56 (1H, dd, J=2.6, 11.0 Hz), 7.82 (1H, t, J=7.7 Hz), 7.98-8.02 (1H, m), 8.73-8.76 (1H, m) MS(ESI) m/z: 313(M+H)+ The title compound was obtained in a similar manner as in Example 102 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.9 Hz), 2.88-2.98 (2H, m), 3.10-3.17 (2H, m), 3.41-3.49 (1H, m), 4.04-4.10 (1H, m), 4.45-4.51 (1H, m), 7.09 (1H, dd, J=2.5, 8.4 Hz), 7.49 (1H, d, J=3.2 Hz), 7.54-7.58 (1H, m), 7.96 (1H, d, J=3.2 Hz) MS(ESI) m/z: 319(M+H)+ The title compound was obtained in a similar manner as in Example 102 except that 2-(tributylstannyl)oxazole was used instead of 2-(tributylstannyl)pyridine. MS(ESI) m/z: 303(M+H)+ The title compound was obtained in a similar manner as in Example 15(a) except that 5-chloro-7-cyano-2-mercaptobenzoxazole obtained in Reference Example 8 was used instead of 5-chloro-7-ethoxycarbonyl-2-mercaptobenzoxazole. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-cyanobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 105(a) (363 mg) was dissolved in ethanol (7.3 mL), hydroxyamine hydrochloride (80 mg) and diisopropylethylamine (0.26 mL) were added thereto, and the resulting mixture was stirred in an oil bath at 85° C. for 3.5 hours. Water was added, the product was extracted with ethyl acetate, the organic layer was washed with a saturated saline solution and then dried over magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=2:1) to obtain 372 mg of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-hydroxycarbamidoyl)-3-methylpiperazine obtained in Example 105(b) (370 mg) was dissolved in trimethyl orthoformate (3.7 mL), boron trifluoride-ethyl ether complex (catalytic amount) was added, and the resulting mixture was stirred in an oil bath at 55° C. for 1 hour. The reaction solvent was distilled off under reduced pressure, then chloroform (6 mL) and trifluoroacetic acid (2 mL) were added, and the resulting mixture was stirred at room temperature for 1.5 hours. A 1 N aqueous solution of sodium hydroxide was added to the reaction mixture, the product was extracted with chloroform, then the organic layer was washed with a saturated saline solution and dried over magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=10:1) to obtain 117 mg of the title compound. MS(ESI) m/z: 320(M+H)+ The title compound was obtained in a similar manner as in Example 96(a) except that 2-hydroxyethylamine was used instead of dimethylamine. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-hydroxyethyl)aminocarbonyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 106(a) (0.5 mmol) was dissolved in 1,4-dioxane (2.5 mL), the resulting mixture was added to a solution of triphenylphosphine (203 mg) and DDQ (175 mg) dissolved in 1,4-dioxane (2.5 mL), and the resulting mixture was stirred at room temperature for 1 hour. A 1 N aqueous solution of sodium hydroxide was added to the reaction mixture, the product was extracted with ethyl acetate, and then the organic layer was washed with a saturated saline solution and dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=200:1) to obtain 76 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(4,5-dihydro-oxazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 106(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine MS(ESI) m/z: 321(M+H)+ (S)-5-Chloro-7-hydroxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole obtained in Example 15(c) (166 mg) was dissolved in THF (2.2 mL), sodium hydride (content 60%, 21 mg) was added thereto, the resulting mixture was stirred at room temperature for 30 minutes, then methyl iodide (270 μL) was added thereto, and the resulting mixture was stirred at room temperature for 1.5 hours in this state. Water was added to the reaction mixture, the product was extracted with ethyl acetate, the organic layer was washed with a saturated saline solution and then dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=7:3) to obtain 91.5 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-methoxy methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 107(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.6 Hz), 2.83-2.92 (2H, m), 3.06-3.11 (2H, m), 3.33-3.40 (1H, m), 3.42 (3H, s), 3.95-3.99 (1H, m), 4.36-4.42 (1H, m), 4.56-4.63 (2H, m), 7.01 (1H, d, J=2.2 Hz), 7.25 (1H, d, J=2.2 Hz) MS(ESI) m/z: 296(M+H)+ The title compound was obtained in a similar manner as in Example 15(a) except that 7-acetyl-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 3 was used instead of 5-chloro-7-ethoxycarbonyl-2-mercaptobenzoxazole. (S)-1-tert-Butoxycarbonyl-4-(7-acetyl-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 108(a) (394 mg) was dissolved in 1,4-dioxane (5 mL), a Bredereck's reagent (250 μL) was added thereto, and the resulting mixture was stirred in an oil bath at 120° C. for 2.5 hours. The reaction mixture was concentrated under reduced pressure, and the obtained residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=96:4) to obtain 388 mg of the title compound. (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-(dimethylamino)acryloyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 108(b) (314 mg), hydroxyamine-hydrochloride (97 mg), and pyridine (113 μL) were dissolved in ethanol (10 mL), and the resulting mixture was stirred in an oil bath at 80° C. for 20 hours. The reaction mixture was concentrated under reduced pressure, the obtained residue was dissolved in ethyl acetate and washed sequentially with water and a saturated saline solution, then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=96:4) to obtain 73 mg of a crude product. The obtained product was dissolved in chloroform (1.8 mL), trifluoroacetic acid (0.9 mL) was added thereto, and the resulting mixture was stirred at room temperature for 1.5 hours. The reaction mixture was concentrated under reduced pressure, the obtained residue was dissolved in ethyl acetate, sequentially washed with water and a saturated saline solution, then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=96:4) to obtain 29.6 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.6 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.39-3.47 (1H, m), 4.00-4.03 (1H, m), 4.41-4.46 (1H, m), 6.84 (1H, d, J=1.7 Hz), 7.37 (1H, d, J=2.0 Hz), 7.54 (1H, d, J=2.0 Hz), 8.54 (1H, d, J=1.7 Hz) MS(ESI) m/z: 319(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-(dimethylamino)acryloyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 108(b) (74 mg) and hydroxyamine hydrochloride (23 mg) were dissolved in ethanol (3.0 mL), and the resulting mixture was stirred in an oil bath at 80° C. for 20 hours. The reaction mixture was concentrated under reduced pressure, the obtained residue was dissolved in ethyl acetate, sequentially washed with water and a saturated saline solution, then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=96:4) to obtain 53.9 mg of a crude product. The obtained product was dissolved in chloroform (1.3 mL), trifluoroacetic acid (0.65 mL) was added, and the resulting mixture was stirred at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure, the obtained residue was dissolved in ethyl acetate, sequentially washed with water and a saturated saline solution, then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, chloroform:methanol=96:4) to obtain 31.4 mg of the title compound. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.6 Hz), 2.87-2.96 (2H, m), 3.09-3.15 (2H, m), 3.41-3.48 (1H, m), 4.00-4.04 (1H, m), 4.41-4.47 (1H, m), 6.73 (1H, d, J=2.0 Hz), 7.36 (1H, d, J=2.0 Hz), 7.51 (1H, d, J=2.0 Hz), 8.37 (1H, d, J=1.7 Hz) MS(ESI) m/z: 319(M+H)+ The title compound was obtained in a similar manner as in Example 2 except that 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 was used instead of 5-chloro-7-methoxy-2-mercaptobenzoxazole. 1H-NMR (400 MHz, CD3OD) δ: 1.40 (3H, d, J=7.2 Hz), 2.85(1H, dt, J=3.6, 12.8 Hz), 2.94 (1H, d, J=12.8 Hz), 3.06 (1H, dd, J=4.0, 12.8 Hz), 3.10-3.12 (1H, m), 3.41(1H, dt, J=3.6, 12.8 Hz), 3.94-3.97 (1H, m), 4.35-4.37 (1H, m), 7.19-7.20 (2H, m) MS(ESI) m/z: 330(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-cyano-2-mercaptobenzoxazole obtained in Reference Example 17 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-cyanobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 111(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-cyano-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 111(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.8 Hz), 2.88-2.96 (2H, m), 3.10-3.18 (2H, m), 3.42-3.52 (1H, m), 4.01-4.06 (1H, m), 4.43-4.49 (1H, m), 7.32-7.36 (1H, m), 7.61 (1H, d, J=1.6 Hz), 7.83-7.87 (1H, m), 7.95-8.00 (1H, m), 8.19 (1H, d, J=1.6 Hz), 8.76-8.78 (1H, m) MS(APCI) m/z: 320(M+H)+ The title compound was obtained in a similar manner as in Example 111 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. MS(ESI) m/z: 326(M+H)+ The title compound was obtained in a similar manner as in Example 111 except that 2-(tributylstannyl)oxazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.47 (3H, d, J=6.8 Hz), 2.87-3.00 (2H, m), 3.08-3.19 (2H, m), 3.44-3.53 (1H, m), 4.08-4.17 (1H, m), 4.48-4.55 (1H, m), 7.36 (1H, d, J=0.73 Hz), 7.61 (1H, d, J=1.6 Hz), 7.83 (1H, d, J=0.73 Hz), 7.99 (1H, d, J=1.6 Hz) MS(ESI) m/z: 310(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-methyl-2-mercaptobenzoxazole obtained in Reference Example 18 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 114(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 114(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. MS(APCI) m/z: 309(M+H)+ The title compound was obtained in a similar manner as in Example 114 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. MS(APCI) m/z: 315(M+H)+ The title compound was obtained in a similar manner as in Example 114 except that 2-(tributylstannyl)oxazole was used instead of 2-(tributylstannyl)pyridine. MS(ESI) m/z: 299(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that a mixture of 7-bromo-5-fluoro-2-mercapto-4-(trifluoromethyl)benzoxazole, and 7-bromo-5-fluoro-2-mercapto-6-(trifluoromethyl)benzoxazole obtained in Reference Example 19 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 117(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 117(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.96 (2H, m), 3.09-3.15 (2H, m), 3.42-3.49 (1H, m), 4.07-4.11 (1H, m), 4.47-4.52 (1H, m), 7.34(1H, ddd, J=1.0, 4.9, 7.6 Hz), 7.64 (1H, d, J=12.7 Hz), 7.85(1H, dt, J=2.0, 7.8 Hz), 8.02 (1H, dd, J=1.0, 8.1 Hz), 8.76-8.78 (1H, m) MS (ESI) m/z: 381(M+H)+ The title compound was obtained in a similar manner as in Example 114 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.47 (3H, d, J=6.8 Hz), 2.88-2.98 (2H, m), 3.11-3.16 (2H, m), 3.45-3.53 (1H, m), 4.13-4.17 (1H, m), 4.52-4.58 (1H, m), 7.56 (1H, d, J=3.2 Hz), 7.63(1H, d, J 12.5 Hz), 8.01 (d, 1H, J=3.2 Hz) MS(ESI) m/z: 387(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83 (b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 117(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.8 Hz), 2.86-2.96 (2H, m), 3.09-3.15 (2H, m), 3.43-3.50 (1H, m), 4.06-4.10 (1H, m), 4.45-4.51 (1H, m), 6.57 (1H, dd, J=2.0, 2.7 Hz), 7.47 (1H, d, J=12.7 Hz), 7.80 (1H, d, J=1.7 Hz), 8.25 (dd, 1H, J=0.5, 2.7 Hz) MS(ESI) m/z: 370(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-4,6-difluoro-2-mercaptobenzoxazole obtained in Reference Example 20 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4,6-difluorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 120(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4,6-difluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 120(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.6 Hz), 2.86-2.94 (2H, m), 3.09-3.13 (2H, m), 3.39-3.46 (1H, m), 4.02-4.06 (1H, m), 4.43-4.49 (1H, m), 7.33-7.36 (1H, m), 7.48 (1H, d, J=7.8 Hz), 7.81(1H, dt, J=2.0, 7.8 Hz), 8.76-8.78 (1H, m) MS(ESI) m/z: 365(M+H)+ The title compound was obtained in a similar manner as in Example 120 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.40-3.47 (1H, m), 4.02-4.06 (1H, m), 4.43-4.49 (1H, m), 7.57 (1H, d, J=3.4 Hz), 8.04 (d, 1H, J=3.4 Hz) MS(ESI) m/z: 371(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-4,5,6-trifluoro-2-mercaptobenzoxazole obtained in Reference Example 21 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-4,5,6-trifluorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 122(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(4,5,6-trifluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 122(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 2.79-2.94 (2H, m), 3.01-3.12 (2H, m), 3.31-3.45 (1H, m), 3.89-3.99 (1H, m), 4.35-4.45 (1H, m), 7.35(1H, ddd, J=7.6, 4.9, 1.1 Hz), 7.61-7.70 (1H, m), 7.80-7.88 (1H, m), 8.75-8.81 (1H, m) MS(ESI) m/z: 349(M+H)+ The title compound was obtained in a similar manner as in Example 122 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.84-2.99 (2H, m), 3.04-3.16 (2H, m), 3.38-3.53 (1H, m), 4.01-4.10 (1H, m), 4.40-4.54 (1H, m), 7.53-7.59 (1H, m), 8.02-8.08 (1H, m) MS(ESI) m/z: 355(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-4,5,6-trifluorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 122(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.79-2.94 (2H, m), 3.01-3.15 (2H, m), 3.32-3.44 (1H, m), 3.89-4.00 (1H, m), 4.34-4.46 (1H, m), 6.51-6.57 (1H, m), 7.80-7.87 (2H, m) MS(ESI) m/z: 338(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-2-mercapto-5-trifluoromethylbenzoxazole obtained in Reference Example 22 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 125(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(7-(pyridin-2-yl)-5-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 125(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. MS(ESI) m/z: 363(M+H)+ The title compound was obtained in a similar manner as in Example 125 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. MS(ESI) m/z: 369(M+H)+ The title compound was obtained in a similar manner as in Example 114 except that 2-(tributylstannyl)oxazole was used instead of 2-(tributylstannyl)pyridine. MS(ESI) m/z: 353(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-4-fluoro-2-mercaptobenzoxazole obtained in Reference Example 23 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-fluorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 128(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 128(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=6.9 Hz), 2.87-2.95 (2H, m), 3.09-3.14 (2H, m), 3.41-3.47 (1H, m), 4.02-4.05 (1H, m), 4.45-4.50 (1H, m), 7.27-7.29 (1H, m), 7.81(1H, dt, J=1.9, 7.9 Hz), 7.89 (1H, d, J=6.9 Hz), 7.92-7.96 (1H, m), 8.72-8.74 (1H, m) MS(ESI) m/z: 347(M+H)+ The title compound was obtained in a similar manner as in Example 128 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (500 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.89-2.96 (2H, m), 3.11-3.15 (2H, m), 3.44-3.50 (1H, m), 4.08-4.11 (1H, m), 4.51-4.52 (1H, m), 7.47 (1H, d, J=3.3 Hz), 7.89 (1H, d, J=6.5 Hz), 7.94 (d, 1H, J=3.3 Hz) MS(ESI) m/z: 353(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-fluorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 128(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.42-3.48 (1H, m), 4.00-4.03 (1H, m), 4.43-4.48 (1H, m), 6.52-6.53 (1H, m), 7.62 (1H, d, J=6.0 Hz), 7.76 (1H, d, J=1.7 Hz), 8.10 (1H, d, J=2.5 Hz) MS(ESI) m/z: 336(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-methylbenzoxazole obtained in Reference Example 24 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 131(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 131(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.7 Hz), 2.54 (3H, s), 2.84-2.98 (2H, m), 3.06-3.18 (2H, m), 3.42 (1H, m), 3.96-4.07 (1H, m), 4.39-4.51 (1H, m), 7.21-7.30 (1H, m), 7.79(1H, td, J=1.9, 7.8 Hz), 7.87 (1H, s), 7.96(1H, dt, J=1.0, 8.0 Hz), 8.69-8.76 (1H, m) MS(ESI) m/z: 343(M+H)+ The title compound was obtained in a similar manner as in Example 131 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.53 (3H, s), 2.85-3.01 (2H, m), 3.11-3.15 (2H, m), 3.44 (1H, m), 4.02-4.13 (1H, m), 4.43-4.57 (1H, m), 7.44 (1H, d, J=3.3 Hz), 7.87 (1H, s), 7.93 (d, 1H, J=3.3 Hz) MS(ESI) m/z: 349(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 131(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.7 Hz), 2.50 (3H, s), 2.83-2.98 (2H, m), 3.06-3.17 (2H, m), 3.42 (1H, m), 3.94-4.06 (1H, m), 4.37-4.49 (1H, m), 6.46-6.54 (1H, m), 7.63 (1H, s), 7.75 (1H, d, J=1.4 Hz), 8.14 (1H, d, J=2.4 Hz) MS(ESI) m/z: 332(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-fluoro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 25 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 134(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 134(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.84-2.98 (2H, m), 3.05-3.17 (2H, m), 3.44(1H, dt, J=3.5, 12.6 Hz), 4.05 (1H, dd, J=2.0, 13.0 Hz), 4.40-4.54 (1H, m), 7.30(1H, ddd, J=1.1, 4.8, 7.5 Hz), 7.68 (1H, d, J=12.2 Hz), 7.82(1H, dt, J=1.9, 7.8 Hz), 7.98(1H, td, J=1.0, 8.0 Hz), 8.70-8.79 (1H, m) MS(ESI) m/z: 397(M+H)+ The title compound was obtained in a similar manner as in Example 134 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.85-3.00 (2H, m), 3.06-3.20 (2H, m), 3.46(1H, dt, J=3.6, 12.6 Hz), 4.11(1H, td, J=1.8, 11.4 Hz), 4.44-4.59 (1H, m), 7.50 (1H, d, J=3.3 Hz), 7.66 (1H, d, J=11.6 Hz), 7.97 (1H, d, J=3.3 Hz) MS(ESI) m/z: 403(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83 (b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 134(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.82-3.00 (2H, m), 3.05-3.17 (2H, m), 3.44(1H, dt, J=3.5, 12.7 Hz), 4.04 (1H, dd, J=2.0, 13.0 Hz), 4.38-4.54 (1H, m), 6.54 (1H, dd, J=1.8, 2.5 Hz), 7.47 (1H, d, J=11.9 Hz), 7.77 (1H, d, J=1.7 Hz), 8.17 (1H, d, J=2.6 Hz) MS(ESI) m/z: 386(M+H)+ (S)-5-Chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-6-methylbenzoxazole obtained in Reference Example 26 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 137(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-6-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 137(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.33 (3H, d, J=6.8 Hz), 2.30 (3H, s), 2.77-2.86 (2H, m), 3.01-3.05 (2H, m), 3.25-3.32 (1H, m), 3.79-3.82 (1H, m), 4.24-4.30 (1H, m), 7.32-7.46 (3H, m), 7.82(1H, dt, J=1.7, 7.8 Hz), 8.77 (1H, d, J=4.9 Hz) MS(ESI) 343(M+H)+ The title compound was obtained in a similar manner as in Example 137 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.38 (3H, d, J=6.8 Hz), 2.54 (s, 3H), 2.81-2.90 (2H, m), 3.04-3.08 (2H, m), 3.31-3.38 (1H, m), 3.88-3.92 (1H, m), 4.30-4.36 (1H, m), 7.42 (1H, s), 7.55 (1H, d, J=3.4 Hz), 8.01 (d, 1H, J=3.4 Hz) MS(ESI) m/z: 349(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 137(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.35 (3H, d, J=6.8 Hz), 2.19 (3H, s), 2.77-2.87 (2H, m), 3.01-3.05 (2H, m), 3.27-3.34 (1H, m), 3.81-3.85 (1H, m), 4.26-4.32 (1H, m), 6.52 (1H, t, J=2.4 Hz), 7.41 (1H, s), 7.64 (1H, d, J=2.4 Hz), 7.80 (1H, d, J=1.7 Hz) MS(ESI) m/z: 332(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-6-methoxybenzoxazole obtained in Reference Example 27 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 102(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-methoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 140(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-6-methoxy-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 140(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.34 (3H, d, J=6.9 Hz), 2.78-2.87 (2H, m), 2.96-3.06 (2H, m), 3.28-3.35 (1H, m), 3.58 (3H, s), 3.84-3.88 (1H, m), 4.39-4.23 (1H, m), 7.33(1H, ddd, J=1.2, 4.9, 7.5 Hz), 7.37 (1H, s), 7.71(1H, dt, J=1.0, 7.9 Hz), 7.82 (1H, m), 8.77 (1H, m) MS(ESI) m/z: 359(M+H)+ The title compound was obtained in a similar manner as in Example 140 except that 2-(tributylstannyl)thiazole was used instead of 2-(tributylstannyl)pyridine. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 2.85-2.92 (2H, m), 3.08-3.12 (2H, m), 3.38-3.45 (1H, m), 3.89 (3H, s), 4.02-4.06 (1H, m), 4.42-4.47 (1H, m), 7.38 (1H, s), 7.52 (1H, d, J=3.3 Hz), 8.03 (d, 1H, J=3.3 Hz) MS(ESI) m/z: 365(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that a mixture of 7-bromo-5-chloro-6-cyano-2-mercaptobenzoxazole and 7-bromo-5-chloro-4-cyano-2-mercaptobenzoxazole obtained in Reference Example 28 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-cyano benzoxazol-2-yl)-3-methylpiperazine obtained in Example 142(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycathonyl-4-(5-chloro-6-cyano-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 142(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.86-2.97 (2H, m), 3.08-3.15 (2H, m), 3.43-3.50 (1H, m), 4.04-4.06 (1H, m), 4.44-4.49 (1H, m), 7.42 (1H, s), 7.63 (1H, d, J=3.2 Hz), 8.12 (1H, d, J=3.2 Hz) MS(ESI) m/z: 360(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that a mixture of 7-bromo-5-chloro-6-cyano-2-mercaptobenzoxazole and 7-bromo-5-chloro-4-cyano-2-mercaptobenzoxazole obtained in Reference Example 28 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-cyanobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 143(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-cyano-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 143(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.48 (3H, d, J=6.8 Hz), 2.88-2.99 (2H, m), 3.10-3.18 (2H, m), 3.47-3.55 (1H, m), 4.14-4.18 (1H, m), 4.55-4.61 (1H, m), 7.59 (1H, d, J=3.2 Hz), 7.91 (1H, s), 8.03 (1H, d, J=3.2 Hz) MS(ESI) m/z: 360(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that a mixture of 7-bromo-5-fluoro-6-trifluoromethyl-2-mercaptobenzoxazole and 7-bromo-5-fluoro-4-trifluoromethyl-2-mercaptobenzoxazole obtained in Reference Example 19 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 144(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-fluoro-6-trifluoromethyl-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 144(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-m ethylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.37 (3H, d, J=6.8 Hz), 2.77-2.89 (2H, m), 3.00-3.06 (2H, m), 3.29-3.37 (1H, m), 3.83-3.86 (1H, m), 4.28-4.34 (1H, m), 7.17 (1H, d, J=11.0 Hz), 7.59 (1H, d, J=3.4 Hz), 8.00 (d, 1H, J=3.4 Hz) MS(ESI) m/z: 387(M+H)+ Copper(I) iodide (38 mg), L-proline (46 mg), and sodium hydroxide (16 mg) were dissolved in DMSO (1.0 mL), and the resulting mixture was stirred in an oil bath at 100° C. for 5 minutes. (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (86 mg) and sodium methanesulfinate (41 mg) were added to the reaction mixture, and the reaction was performed by using a microwave reactor at 140° C. for 2 hours. Water was added to the reaction mixture, and the product was extracted with ethyl acetate. The organic layer was washed with a saturated saline solution and dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=2:3) to obtain 50 mg of the title compound. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(methylsulfonyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 145(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.82-2.97 (2H, m), 3.06-3.13 (2H, m), 3.21 (3H, s), 3.36-3.49 (1H, m), 3.95-4.06 (1H, m), 4.36-4.48 (1H, m), 7.47 (1H, d, J=2.0 Hz), 7.50 (1H, d, J=2.0 Hz) MS(ESI) in/z: 330(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 41(a) (108 mg), N-iodosuccinimide (56 mg), and acetonitrile (2.0 mL) were dissolved in trifluoroacetic acid (11 mL), and the resulting mixture was stirred in an oil bath at 70° C. for 7 hours. Water was added to the reaction mixture, the product was extracted with ethyl acetate and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was dissolved in chloroform (2 mL), trifluoroacetic acid (1 mL) was added thereto, and the resulting mixture was stirred at room temperature for 1 hour. An aqueous solution of saturated sodium hydrogencarbonate was added to the reaction mixture, the product was extracted with a mixed solution of chloroform and methanol and then dried over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure, and the residue was purified by fractional HPLC (for acetonitrile:water=from 1:3 to 3:1) to obtain 11 mg of the title compound. 1H-NMR (500 MHz, CDCl3) δ: 1.44 (3H, d, J=7.0 Hz), 2.87-2.95 (2H, m), 3.10-3.13 (2H, m), 3.42-3.48 (1H, m), 4.06-4.09 (1H, m), 4.47-4.49 (1H, m), 7.28-7.31 (1H, m), 7.79-7.83 (1H, m), 7.96 (1H, d, J=8.0 Hz), 8.00 (1H, s), 8.74 (1H, d, J=4.0 Hz) MS(ESI) m/z: 455(M+H)+ In a similar manner as in Example 146, all the reagents and the solvents were reacted in an amount of 3 times, and as a result, 104 mg of the title compound, i.e., a positional isomer of the compound obtained in Example 146 was obtained. 1H-NMR (400 MHz, CDCl3) δ: 1.32 (3H, d, J=6.8 Hz), 2.71-2.88 (2H, m), 2.95-3.06 (2H, m), 3.21-3.34 (1H, m), 3.78(1H, dd, J=1.9 Hz, 13.0 Hz), 4.20-4.32 (1H, m), 7.38(1H, ddd, J=7.6, 4.9, 1.2 Hz), 7.42-7.46 (1H, m), 7.50 (1H, s), 7.80-7.89 (1H, m), 8.74-8.79 (1H, m) MS(ESI) m/z: 455(M+H)+ (S)-5-Chloro-4-iodo-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benz oxazole obtained in Example 146 (103 mg), di-tert-butyl dicarbonate (42.6 mg), and sodium hydrogencarbonate (21.8 mg) were dissolved in water (2 mL) and 1,4-dioxane (2 mL), and the resulting mixture was stirred at room temperature for 14 hours. Water was added to the reaction mixture, the product was extracted with ethyl acetate, then the organic layer was washed with a saturated saline solution and dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure to obtain 51 mg of the title compound as a crude product. The title compound was obtained in a similar manner as in Example 27(b) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-iodo-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 148(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine and that phenylboronic acid was used instead of cyclopropyl boronic acid. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-phenyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 148(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.81-2.97 (2H, m), 3.04-3.15 (2H, m), 3.32-3.47 (1H, m), 3.95-4.07 (1H, m), 4.36-4.48 (1H, m), 7.29(1H, ddd, J=7.5, 4.8, 1.1 Hz), 7.36-7.43 (1H, m), 7.44-7.52 (2H, m), 7.59-7.66 (2H, m), 7.79-7.87 (1H, m), 8.00 (1H, s), 8.02 (1H, m), 8.72-8.80 (1H, m) MS(ESI) m/z: 405(M+H)+ The title compound was obtained in a similar manner as in Example 27(b) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-iodo-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 148(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-cyclopropyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 149(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine 1H-NMR (400 MHz, CDCl3) δ: 1.00-1.11 (2H, m), 1.47-1.60 (5H, m), 2.23-2.38 (1H, m), 3.04-3.18 (1H, m), 3.20-3.38 (2H, m), 3.40-3.52 (1H, m), 3.62-3.77(114, m), 4.15-4.27 (1H, m), 4.60-4.74(114, m), 7.23-7.31 (1H, m), 7.75-7.83 (1H, m), 7.84-7.91 (2H, m), 8.70-8.78 (1H, m) MS(ESI) m/z: 369(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (430 mg) was dissolved in THF (1.0 mL), a solution of 2,2,6,6-tetramethylpiperidinyl-magnesium chloride-lithium chloride complex (1.0 M, THY/toluene solution, 1.2 mL) was added thereto, the resulting mixture was stirred at −55° C. for 2 hours, then S-methyl methanethiosulfonate (113 μL) was added thereto, and the resulting mixture was further stirred at −20° C. for 2 hours. A saturated aqueous solution of ammonium chloride was added to the reaction mixture, the product was extracted with ethyl acetate and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=4:1) to obtain 371 mg of the title compound as a crude product. The title compound was obtained in a similar manner as in Examples 41(a) and 41(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(methylthio)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 150(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.9 Hz), 2.72 (3H, s), 2.83-2.99 (2H, m), 3.03-3.19 (2H, m), 3.43 (1H, m), 4.06 (1H, dd, J=13.0, 2.0 Hz), 4.42-4.54 (1H, m), 7.26-7.28 (1H, m), 7.80 (1H, m), 7.92 (1H, s), 7.96 (1H, m), 8.71-8.77 (1H, m) MS(ESI) m/z: 375(M+H)+ (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a) (430 mg) was dissolved in THF (1.0 mL), a solution of 2,2,6,6-tetramethylpiperidinyl-magnesium chloride-lithium chloride complex (1.0 M, THF/toluene solution, 1.2 mL) was added thereto, and the resulting mixture was stirred at −55° C. for 2 hours, then S-methyl methanethiosulfate (113 μL) was added thereto, and the resulting mixture was further stirred at −20° C. for 2 hours. A saturated aqueous solution of ammonium chloride was added to the reaction mixture, the product was extracted with ethyl acetate and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue and m-chloroperbenzoic acid (155 mg) were dissolved in chloroform (1.0 mL), and the resulting mixture was stirred at room temperature for 2 hours. Water was added to the reaction mixture, the product was extracted with chloroform and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=2:1) to obtain 97.4 mg of the title compound as a crude product. The title compound was obtained in a similar manner as in Examples 41(a) and 41(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(methylsulfonyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 151(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (500 MHz, CDCl3) δ: 1.53 (3H, t, J=6.9 Hz), 3.08(1H, td, J=3.8, 12.5 Hz), 3.18 (1H, d, J=12.9 Hz), 3.24-3.33 (1H, m), 3.37(1H, J=11.0H), 3.49 (3H, s), 3.63-3.74 (1H, m), 4.25 (1H, dd, J=2.1, 13.7 Hz), 4.64-4.74 (1H, m), 7.36(1H, ddd, J=1.1, 4.9, 7.6 Hz), 7.87(1H, dt, J=1.9, 7.7 Hz), 7.93 (1H, s), 7.95-7.99 (1H, m), 8.75-8.77 (1H, m) MS(ESI) in/z: 407(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 41(a) (53.5 mg) and N-bromosuccimide (22 mg) were dissolved in acetonitrile (1.0 mL), and the resulting mixture was stirred at room temperature for 3 hours. Water was added to the reaction mixture, the product was extracted with ethyl acetate and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain 65.7 mg of the title compound as a crude product. The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(6-bromo-5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 152(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.33 (3H, d, J=6.8 Hz), 2.76-2.86 (2H, m), 3.00-3.04 (2H, m), 3.25-3.33 (1H, m), 3.78-3.82 (1H, m), 4.28-4.29 (1H, m), 7.36-7.39 (1H, m), 7.47 (1H, s), 7.51 (1H, d, J=7.6 Hz), 7.8-7.86 (1H, m), 8.77 (1H, d, J=4.4 Hz) MS(ESI) m/z: 407(M+H)+ (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-m ethylpiperazine obtained in Example 16(a) (430 mg) was dissolved in THF (1.0 mL), a solution of 2,2,6,6-tetramethylpiperidinyl-magnesium chloride-lithium chloride complex (1.0 M, THF/toluene solution, 12 mL) was added thereto, and the resulting mixture was stirred at −55° C. for 2 hours and then was further stirred in an air atmosphere at −20° C. for 2 hours. A saturated aqueous solution of ammonium chloride was added to the reaction mixture, the product was extracted with ethyl acetate and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue and m-chloroperbenzoic acid (155 mg) were dissolved in chloroform (1.0 mL), and the resulting mixture was stirred at room temperature for 2 hours. Water was added to the reaction mixture, the product was extracted with chloroform and then dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=2:1) to obtain 57 mg of the title compound as a crude product. The title compound was obtained in a similar manner as in Example 107(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-hydroxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 153(a) was used instead of (S)-5-chloro-7-hydroxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole. The title compound was obtained in a similar manner as in Examples 41(a) and 41(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-methoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 153(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.9 Hz), 2.93-2.96 (2H, m), 3.12-3.15 (2H, m), 3.38-3.45 (1H, m), 4.02 (1H, m), 4.31 (3H, s), 4.45 (1H, m), 7.21-7.25 (1H, m), 7.78 (1H, m), 7.88 (1H, s), 7.92 (1H, m), 8.68-8.75 (1H, m) MS(ESI) m/z: 359(M+H)+ The title compound was obtained in a similar mariner as in Example 2 except that 5-chloro-7-methyl-2-mercaptobenzoxazole was used instead of 5-chloro-7-methoxy-2-mercaptobenzoxazole. MS(ESI) m/z: 266(M+H)+ The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-methoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 153(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-4-methoxy-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 155(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.7 Hz), 2.86-2.99 (2H, m), 3.10-3.18 (2H, m), 3.47-3.55 (1H, m), 4.00-4.12 (1H, m), 4.34 (3H, s), 4.40-4.55 (1H, m), 7.41 (1H, d, J=3.3 Hz), 7.89 (1H, s), 7.91 (d, 1H, J=3.3 Hz) MS(ESI) m/z: 365(M+H)+ The title compound was obtained in a similar manner as in Examples 83(a) and 83(b) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-methoxybenzoxazol-2-yl)-3-methylpiperazine obtained in Example 153(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43(31-1, d, J=6.2 Hz), 2.86-2.99 (2H, m), 3.08-3.17 (2H, m), 3.38-3.47 (1H, m), 3.97-4.04 (1H, m), 4.24 (3H, s), 4.39-4.48 (1H, m), 6.50 (t, 1H, J=2.1 Hz), 7.59 (1H, s), 7.74 (d, 1H, J=1.4 Hz), 8.07 (d, 1H, J=2.2 Hz) MS(ESI) m/z: 348(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 12 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 and that (R)-1-tert-butoxycarbonyl-3-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 41(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 157(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 157(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.43 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.09-3.14 (2H, m), 3.40-3.48 (1H, m), 4.03-4.06 (1H, m), 4.44-4.50 (1H, m), 7.29-7.32 (1H, m), 7.81-7.85 (1H, m), 7.93 (1H, s), 7.95-7.97 (1H, m), 8.74-8.76 (1H, m) MS(ESI) m/z: 413(M+H)+ The title compound was obtained in a similar manner as in Example 35(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 157(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 158(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.85-3.02 (2H, m), 3.07-3.19 (2H, m), 3.43-3.50 (1H, m), 4.09-4.12 (1H, m), 4.45-4.60 (1H, m), 7.51 (1H, d, J=3.3 Hz), 7.94 (1H, s), 7.97 (1H, d, J=3.2 Hz) MS(ESI) m/z: 419(M+H)+ The title compound was obtained in a similar manner as in Example 83(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 157(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 159(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.08-3.14 (2H, m), 3.41-3.49 (1H, m), 4.01-4.05 (1H, m), 4.42-4.48 (1H, m), 6.54 (1H, dd, J=1.9, 2.5 Hz), 7.71 (1H, s), 7.77 (1H, d, J=1.4 Hz), 8.15 (1H, d, J=2.6 Hz) MS(ESI) m/z: 402(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-6-(trifluoromethoxy)benzoxazole obtained in Reference Example 29 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9. The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-6-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 160(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-6-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 160(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.4 Hz), 2.82-2.92 (2H, m), 3.05-3.11 (2H, m), 3.36-3.43 (1H, m), 3.95-3.96 (1H, m), 4.38-4.41 (1H, m), 7.43 (1H, s), 7.59 (1H, d, J=3.2 Hz), 8.04 (1H, d, J=3.2 Hz) MS(ESI) m/z: 419(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-6-methoxy-7-methyl-2-mercaptobenzoxazole obtained in Reference Example 30 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.8 Hz), 2.37 (3H, s), 2.91(1H, dt, J=3.6, 12.4 Hz), 3.00 (1H, d, J=12.4 Hz), 3.12 (1H, dd, J=4.4, 12.4 Hz), 3.20 (1H, d, J=12 Hz), 3.43(1H, dt, J=3.6, 12.8 Hz), 3.71 (3H, s), 3.99-4.03 (1H, m), 4.43-4.46 (1H, m), 7.19 (1H, s) MS(ESI) m/z: 296(M+H)+ (S)-5-Chloro-6-methoxy-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole obtained in Example 161 (216 mg) was dissolved in dichloromethane (8 mL), boron tribromide (a 1 M solution in dichloromethane, 2.9 mL) was added thereto at room temperature, and then the resulting mixture was stirred for 3 hours in this state. An aqueous solution of sodium hydrogencarbonate was added to the reaction mixture, and the product was extracted with ethyl acetate. The solvent was distilled off under reduced pressure to obtain 130 mg of the title compound. 1H-NMR (400 MHz, CD3OD) δ: 1.36 (3H, d, J=6.8 Hz), 2.31 (3H, s), 2.81 (1H, dd, J=4, 12.4 Hz), 2.90 (1H, d, J=12.4 Hz), 3.03 (1H, dd, J=4, 13.2 Hz), 3.06 (1H, d, J=7.6 Hz), 3.38-3.40 (1H, m), 3.85-3.88 (1H, m), 4.26-4.30 (1H, m), 7.03 (1H, s) MS(ESI) m/z: 282(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 4-bromo-6-chloro-2-mercaptobenzoxazole obtained in Reference Example 31 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. MS(ESI) m/z: 330(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 4-bromo-6-chloro-2-mercaptobenzoxazole obtained in Reference Example 31 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Examples 23(a) and 23 (b) except that (S)-1-tert-butoxycarbonyl-4-(4-bromo-6-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 164(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.5 Hz), 2.85-2.93 (2H, m), 3.08-3.13 (2H, m), 3.36-3.43 (1H, m), 4.03-4.07 (1H, m), 4.41-4.47 (1H, m), 6.54 (1H, dd, J=2.0, 3.4 Hz), 7.13 (1H, d, J=2.0 Hz), 7.36 (1H, d, J=3.4 Hz), 7.49 (1H, d, J=1.7 Hz), 7.60 (1H, d, J=2.0 Hz) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar mariner as in Example 16(a) except that 4-bromo-6-chloro-2-mercaptobenzoxazole obtained in Reference Example 31 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 and that (R)-1-tert-butoxycarbonyl-3-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Examples 23(a) and 23(b) except that (R)-1-tert-butoxycarbonyl-4-(4-bromo-6-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 165(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). 1H-NMR (400 MHz, CDCl3) δ: 1.41 (3H, d, J=6.6 Hz), 2.85-2.93 (2H, m), 3.08-3.13 (2H, m), 3.36-3.43 (1H, m), 4.03-4.07 (1H, m), 4.41-4.47 (1H, m), 6.54 (1H, dd, J=2.0, 3.4 Hz), 7.13 (1H, d, J=2.0 Hz), 7.36 (1H, d, J=2.9 Hz), 7.49 (1H, d, J=1.7 Hz), 7.60 (1H, d, J=2.0 Hz) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar manner as in Examples 33(a) and 33(b) except that (S)-1-tert-butoxycarbonyl-4-(4-bromo-6-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 164(a) was used instead of (S)-1-tert-butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). 1H-NMR (400 MHz, CDCl3) δ: 1.46 (3H, d, J=6.8 Hz), 2.91-3.03 (2H, m), 3.14-3.22 (2H, m), 3.44-3.51 (1H, m), 4.08-4.11 (1H, m), 4.48-4.54 (1H, m), 6.47 (1H, dd, J=1.7, 2.4 Hz), 7.16 (1H, d, J=2.0 Hz), 7.72 (1H, d, J=1.7 Hz), 7.95 (1H, d, J=1.7 Hz), 8.99 (1H, d, J=2.4 Hz) MS(ESI) m/z: 318(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 4-bromo-2-mercaptobenzoxazole obtained in Reference Example 32 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine 1H-NMR (400 MHz, CDCl3) δ: 1.39 (3H, d, J=6.8 Hz), 2.83-2.93 (2H, m), 3.06-3.11 (2H, m), 3.36(1H, dt, J=3.6, 12.4 Hz), 3.95-3.98 (1H, m), 4.47-4.40 (1H, m), 7.08-7.11 (2H, m), 7.45 (1H, s) MS(ESI) m/z: 296(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-cyano-6-methoxy-2-mercaptobenzoxazole obtained in Reference Example 33 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.40 (3H, d, J=6.8 Hz), 2.83-2.93 (2H, m), 3.06-3.12 (2H, m), 3.39(1H, dt, J=3.6, 12.4 Hz), 3.98 (3H, s), 4.00-4.02 (1H, m), 4.39-4.45 (1H, m), 6.88 (1H, s), 7.28 (1H, s) MS(ESI) m/z: 273(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-6,7-dimethoxy-2-mercaptobenzoxazole obtained in Reference Example 34 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.42 (3H, d, J=6.8 Hz), 2.92(1H, dt, J=4, 12.8 Hz), 3.03 (1H, d, J=12.8 Hz), 3.13 (1H, dd, J=4.4, 12.8 Hz), 3.22(1H, d, J=12.4 Hz), 3.45(1H, dt, J=4, 12.8 Hz), 3.86 (3H, s), 3.98-4.02 (1H, m), 4.15 (3H, s), 4.42-4.45 (1H, m), 7.04 (1H, s) MS(ESI) m/z: 312(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-6-methyl-2-mercaptobenzoxazole obtained in Reference Example 35 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. MS(ESI) m/z: 266(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-6-methoxy-2-mercaptobenzoxazole obtained in Reference Example 36 and (S)-1-tert-butoxycarbonyl-3-methylpiperazine. MS(ESI) m/z: 282(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 5-bromo-7-methyl-2-mercaptobenzoxazole obtained in Reference Example 5 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole. The title compound was obtained in a similar manner as in Examples 20(a) and 20(b) except that (S)-1-tert-butoxycarbonyl-4-(5-bromo-7-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 172(a) was used instead of (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). MS(ESI) m/z: 301(M+H)+ The title compound was obtained in a similar manner as in Examples 16(b) and 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-bromo-7-methylbenzoxazol-2-yl)-3-methylpiperazine obtained in Example 172(a) was used instead of (S)-1-tert-Butoxycarbonyl-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). MS(ESI) m/z: 314(M+H)+ The title compound was obtained in a similar manner as in Example 2 from 5-chloro-7-ethyl-2-mercaptobenzoxazole obtained in Reference Example 7 and (R)-1-tert-butoxycarbonyl-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.30 (3H, t, J=7.7 Hz), 1.57 (3H, d, J=7.1 Hz), 2.77(2H, q, J=7.7 Hz), 3.02-3.11 (1H, m), 3.20-3.30 (2H, m), 3.39-3.47 (1H, m), 3.62-3.71 (1H, m), 4.15-4.22 (1H, m), 4.62-4.70 (1H, m), 6.89 (1H, d, J=2.0 Hz), 7.19 (1H, d, J=2.0 Hz) MS(ESI) m/z: 280(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 12 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 and that 1-tert-butoxycarbonylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 35(a) except that 1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)piperazine obtained in Example 175(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that 1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)piperazine obtained in Example 175(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 2.99-3.08 (4H, m), 3.76-3.85 (4H, m), 7.51 (1H, d, J=3.3 Hz), 7.94 (1H, s), 7.97 (1H, d, J=3.2 Hz) MS(ESI) m/z: 405(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 12 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 and that (R)-1-tert-butoxycarbonyl-2-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 35(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine obtained in Example 176(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine obtained in Example 176(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.19 (3H, d, J=6.1 Hz), 2.83-2.92 (1H, m), 2.92-3.05 (2H, m), 3.12-3.20 (1H, m), 3.26(1H, dt, J=3.3, 12.3 Hz), 4.18-4.32 (2H, m), 7.51 (1H, d, J=3.3 Hz), 7.94 (1H, s), 7.97 (1H, d, J=3.2 Hz) MS(ESI) m/z: 419(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole obtained in Reference Example 12 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole obtained in Reference Example 9 and that (S)-1-tert-butoxycarbonyl-2-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 35(a) except that (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine obtained in Example 177(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine obtained in Example 16(a). The title compound was obtained in a similar manner as in Example 16(c) except that (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine obtained in Example 177(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.19 (3H, d, J=6.1 Hz), 2.83-2.92(111, m), 2.92-3.06 (2H, m), 3.12-3.19 (1H, m), 3.26(1H, dt, J=3.3, 12.3 Hz), 4.18-4.33 (2H, m), 7.51 (1H, d, J=3.3 Hz), 7.94 (1H, s), 7.98 (1H, d, J=3.2 Hz) MS(ESI) m/z: 419(M+H)+ The title compound was obtained in a similar manner as in Example 16(a) except that 7-bromo-5-chloro-2-mercapto-4-(trifluoromethyl)benzoxazole obtained in Reference Example 10 was used instead of 7-bromo-5-chloro-2-mercaptobenzoxazole and that (R)-1-tert-butoxycarbonyl-3-methylpiperazine was used instead of (S)-1-tert-butoxycarbonyl-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 41(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 178(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine. The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 178(b) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.44 (3H, d, J=6.8 Hz), 2.86-2.95 (2H, m), 3.09-3.15 (2H, m), 3.42-3.50 (1H, m), 4.06-4.10 (1H, m), 4.46-4.51 (1H, m), 7.32-7.36 (1H, m), 7.83-7.87 (1H, m), 7.94 (1H, s), 7.99-8.01 (1H, m), 8.76-8.78 (1H, m) MS(ESI) m/z: 397(M+H)+ (R)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 178(a) (100 mg, 0.2 mmol), 2-thiazolyl zinc bromide (0.8 mL, 2.0 equivalents, a 0.5 M solution in THF), [1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct (16 mg, 0.1 equivalents) were dissolved in toluene (1.4 mL), and the resulting mixture was stirred in an oil bath at 85° C. for 2.5 hours. Ethyl acetate was added to the reaction mixture, and the resulting mixture was washed with an aqueous solution of ammonium chloride and a saturated saline solution. The organic layer was dried over anhydrous sodium sulfate, then the solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solvent, hexane:ethyl acetate=7:3) to obtain 85 mg of the title compound. MS(ESI) m/z: 503(M+H)+ The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 179(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.47 (3H, d, J=6.8 Hz), 2.88-2.97 (2H, m), 3.10-3.16 (2H, m), 3.45-3.52 (1H, m), 4.13-4.16 (1H, m), 4.51-4.57 (1H, m), 7.56 (1H, d, J=3.3 Hz), 7.95 (1H, s), 8.01 (1H, d, J=3.2 Hz) MS(ESI) m/z: 403(M+H)+ The title compound was obtained in a similar manner as in Example 45(a) except that (R)-1-tert-butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 178(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine and that pyrazole was used instead of 1,2,3-triazole. The title compound was obtained in a similar manner as in Example 16(c) except that (R)-1-tert-butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine obtained in Example 180(a) was used instead of (S)-1-tert-butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine. 1H-NMR (400 MHz, CDCl3) δ: 1.45 (3H, d, J=6.9 Hz), 2.86-2.96 (2H, m), 3.08-3.15 (2H, m), 3.43-3.51 (1H, m), 4.05-4.09 (1H, m), 4.44-4.50 (1H, m), 6.56 (1H, dd, J=1.8, 2.4 Hz), 7.78 (1H, s), 7.79 (1H, d, J=1.5 Hz), 8.22 (1H, d, J=2.2 Hz) MS(ESI) m/z: 386(M+H)+ In the following description, Table 1 and Table 2 illustrate the compounds of Reference Examples, and Table 3 to Table 11 illustrate the compounds of Examples. The PDE4 inhibitory activity was measured by using scintillation proximity assay (SPA) as follows: one in which a sample compound dissolved in dimethyl sulfoxide was diluted 10-fold with a buffer solution for reaction containing 50 mM Tris-HCl, pH 7.5, 8.3 mM MgCl2, 1.7 mM EDTA and 0.3 mg/mL bovine serum albumin (BSA) was added at 10 μL/well to a 96-well assay plate. Further, PDE4 diluted 750-fold with a buffer solution for reaction was added at 50 μL/well, then [2,8-3H]-Adenosine-3′,5′-cyclic phosphate triethylammonium salt diluted 1000-fold with a buffer solution for reaction was added at 40 μL/well, and the plate was left standing at room temperature for 120 minutes. Thereafter, a suspension of RNA binding YSi-SPA Beads containing 200 mM ZnSO4was added at 50 μL/well, and the plate was left standing at room temperature for 15 minutes to adsorb the enzyme reaction product onto the Beads. Thereafter, the radioactivity was measured with a liquid scintillation counter for 96-well plates. When one supplemented with only a buffer solution for reaction without adding the enzyme preparation was used as a blank and one supplemented with the enzyme preparation but supplemented with only dimethyl sulfoxide instead of the sample solution was used as a control, the inhibition rate of the test compound relative to the control was calculated according to the following calculation expression: The results of measuring the rate of PDE4 inhibition of the test compound at 1 μM by the method mentioned above are shown in Tables 12 to 14. Provided is a compound represented by formula (1a) or a pharmacologically acceptable salt thereof. However, R1 to R6 in the formula each independently represent an alkyl group or the like. 1. A compound represented by formula (1a): wherein
R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted C7-11monocyclic or polycyclic aralkyloxy group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylthio group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a C1-6alkyl group, provided that the case where R1is a carboxy group, the case where R1, R2, R3and R4are hydrogen atoms at the same time and the case where R5and R6are hydrogen atoms at the same time are excluded; or a pharmacologically acceptable salt thereof. 2. The compound or a pharmacologically acceptable salt thereof according to 3. The compound or a pharmacologically acceptable salt thereof according to R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group. 4. A compound selected from
(S)-5-chloro-7-isopropyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-acetyl-2-(2-methylpiperazin-1-yl)benzoxazole, meso-5-chloro-2-(2,6-cis-dimethylpiperazin-1-yl)-7-methylbenzoxazole, (S)-5-fluoro-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-bromo-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-isopropoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethoxycarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-cyano-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethyl-2-(2-isopropylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethyl-2-(2-isobutylpiperazin-1-yl)benzoxazole, (S)-2-(2-n-butylpiperazin-1-yl)-5-chloro-7-ethylbenzoxazole, (S)-5-chloro-7-ethyl-2-(2-ethylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-hydroxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiophen-3-yl)benzoxazole, (S)-5-chloro-7-(furan-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiophen-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-phenylbenzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyrrolidin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(morpholin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(piperidin-1-yl)benzoxazole, (S)-5-chloro-7-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(cyclopentylamino)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-diethylamino-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-dimethylamino-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-cyclopropyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(cyclopentyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-n-propoxybenzoxazole, (S)-5-chloro-7-cyclopentyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-7-n-butyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-7-(1H-imidazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-4-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-5-yl)benzoxazole, (S)-5-chloro-7-(5-methylfuran-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(4-methyl-1H-pyrazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-3-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-4-yl)benzoxazole, (S)-5-chloro-7-cyclohexyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(2H-1,2,3-triazol-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-1,2,4-triazol-1-yl)benzoxazole, (S)-5-chloro-7-isobutyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(2-hydroxymethylphenyl)benzoxazole, (S)-5-chloro-7-(1-methyl-1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(cyclohexylmethyl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(cyclohexyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(cyclopropylmethoxy)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(isothiazol-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-hydroxymethylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyrimidin-2-yl)benzoxazole, (S)-5-chloro-7-(5-chlorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(4-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(6-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(3-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-cyanothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(5-methylthiazol-2-yl)benzoxazole, (S)-5-chloro-7-(2-chlorothiophen-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-carbamoylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(3-cyanopyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-fluorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(3-methylpyridin-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(2-methylthiazol-4-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-phenoxybenzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(2-oxopyrrolidin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(2-oxooxazolidin-3-yl)benzoxazole, (S)-5-chloro-7-(5-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-chlorothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-7-benzyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(5-(hydroxymethyl)thiazol-4-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yloxy)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(5-nitrothiazol-2-yl)benzoxazole, (S)-5-chloro-7-(3-methoxypyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, 5-chloro-2-((S)-2-methylpiperazin-1-yl)-7-(tetrahydrofuran-2-yl)benzoxazole, (S)-5-chloro-7-(4-fluorophenyl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-6-(trifluoromethyl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole, (S)-4,5-difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-4,5-difluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-4,5-difluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-n-propylbenzoxazole, (S)-5-chloro-7-dimethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-diethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-hydroxyaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-carboxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-methylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-ethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1,2,4-oxadiazol-3-yl)benzoxazole, (S)-5-chloro-7-(4,5-dihydrooxazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(methoxymethyl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(isoxazol-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-7-(isoxazol-5-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-7-bromo-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-cyano-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-cyano-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole, (S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole, (S)-5-chloro-4,6-difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-4,6-difluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-4,5,6-trifluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-4,5,6-trifluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-4,5,6-trifluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-5-(trifluoromethyl)benzoxazole, (S)-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-5-(trifluoromethyl)benzoxazole, (S)-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)-5-(trifluoromethyl)benzoxazole, (S)-5-chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (S)-5-chloro-6-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-6-methoxy-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-6-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-4-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethyl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(methylsulfonyl)benzoxazole, (S)-5-chloro-4-iodo-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-6-iodo-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-4-phenyl-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-4-cyclopropyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-4-(methylthio)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-4-(methylsulfonyl)-7-(pyridin-2-yl)benzoxazole, (S)-6-bromo-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole, (S)-5-chloro-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole, (S)-5-chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole, (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole, (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethoxy)benzoxazole, (S)-5-chloro-6-methoxy-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-6-hydroxy-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-4-bromo-6-chloro-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-6-chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (R)-6-chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-6-chloro-2-(2-methylpiperazin-1-yl)-4-(1H-pyrazol-1-yl)benzoxazole, (S)-5-bromo-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-cyano-7-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-6,7-dimethoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-6-methyl-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-5-chloro-6-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-7-methyl-5-(pyrrolidin-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (S)-7-methyl-5-(thiophen-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole, (R)-5-chloro-7-ethyl-2-(2-methylpiperazin-1-yl)benzoxazole, 5-chloro-2-(piperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (R)-5-chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (S)-5-chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole, (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole, (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole, and (R)-5-chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole, or a pharmacologically acceptable salt thereof. 5. A PDE4 inhibitor comprising a compound represented by formula (1a): wherein
R1, R2, R3and R4are each independently one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted C7-11monocyclic or polycyclic aralkyloxy group, an optionally substituted 4- to 10-membered monocyclic or bicyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylthio group, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5and R6are each independently a hydrogen atom or a C1-6alkyl group; or a pharmacologically acceptable salt thereof as an active ingredient. 6. The PDE4 inhibitor according to 7. The PDE4 inhibitor according to R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group. 8. A PDE4 inhibitor comprising a compound represented by formula (1) or a pharmacologically acceptable salt thereof as an active ingredient: wherein
R1is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkyloxy group, an optionally substituted C1-6alkylthio group and an optionally substituted C1-6alkylsulfonyl group, R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, R3is one group selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxy group, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted C1-6alkyloxy group, and R4is one group selected from the group consisting of a hydrogen atom, a halogen atom, a carboxy group, a cyano group, an optionally substituted C1-6alkyl group, an optionally substituted C3-7cycloalkyl group, an optionally substituted C6-10monocyclic or polycyclic aryl group, an optionally substituted C7-11monocyclic or polycyclic aralkyl group, an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, a di-C1-6alkylamino group, an optionally substituted C3-7cycloalkylamino group, an optionally substituted C1-6alkyloxy group, an optionally substituted C3-7cycloalkyloxy group, an optionally substituted C6-10monocyclic or polycyclic aryloxy group, an optionally substituted 5- to 7-membered monocyclic heterocyclyloxy group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom, an optionally substituted C1-6alkylsulfonyl group, an optionally substituted C1-6alkylcarbonyl group, a mono-C1-6alkylaminocarbonyl group, a di-C1-6alkylaminocarbonyl group, an optionally substituted C1-6alkyloxycarbonyl group and an optionally substituted hydroxyaminocarbonyl group, and R5to R8are each independently a hydrogen atom or a C1-6alkyl group. 9. A PDE4 inhibitor comprising the compound or the pharmacologically acceptable salt thereof according to 10. A pharmaceutical composition comprising the compound or the pharmacologically acceptable salt thereof according to 11. A pharmaceutical composition comprising the PDE4 inhibitor according to 12. A pharmaceutical composition comprising the compound or the pharmacologically acceptable salt thereof according to 13. A pharmaceutical composition comprising the PDE4 inhibitor according to 14. A pharmaceutical composition comprising the PDE4 inhibitor according to 15. A method of inhibiting PDE4 comprising administering the compound or the pharmacologically acceptable salt thereof according to 16. A method of inhibiting PDE4 comprising administering the compound or the pharmacologically acceptable salt thereof according to 17. A method of treating diseases caused by PDE4 comprising administering the compound or the pharmacologically acceptable salt thereof according to 18. A method of treating diseases caused by PDE4 comprising administering the compound or the pharmacologically acceptable salt thereof according to TECHNICAL FIELD
BACKGROUND ART
CITATION LIST
Patent Literature
Non Patent Literature
SUMMARY OF INVENTION
Technical Problem
Solution to Problem
[2] The compound or a pharmacologically acceptable salt thereof according to, wherein R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocyclic heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom.
[3] The compound or a pharmacologically acceptable salt thereof according to, wherein
or a pharmacologically acceptable salt thereof.
[5] A PDE4 inhibitor comprising a compound represented by formula (1a):
[6] The PDFA inhibitor according to, wherein R2is one group selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, an optionally substituted C1-6alkyl group and an optionally substituted 5- to 7-membered monocycle heterocyclic group containing 1 to 4 heteroatoms selected from an oxygen atom, a nitrogen atom and a sulfur atom.
[7] The PDE4 inhibitor according to, wherein
[10] A pharmaceutical composition comprising the compound or the pharmacologically acceptable salt thereof according to any one of to as an active ingredient.
[11] A pharmaceutical composition comprising the PDE4 inhibitor according to any one of to as an active ingredient.
[12] A therapeutic agent for diseases caused by PDE4, comprising the compound or the pharmacologically acceptable salt thereof according to any one of to as an active ingredient.
[13] A method for inhibiting PDE4, comprising administering the compound or the pharmacologically acceptable salt thereof according to any one of to to a patient.
[14] A method for treating diseases caused by PDE4, comprising administering the compound or the pharmacologically acceptable salt thereof according to any one of to to a patient.
[15] The compound or the pharmacologically acceptable salt thereof according to any one of to, wherein the compound or the pharmacologically acceptable salt thereof is for use in the inhibition of PDE4.
[16] The compound or the pharmacologically acceptable salt thereof according to any one of to, wherein the compound or pharmacologically acceptable salt thereof is for use in the treatment of diseases caused by PDE4.
[17] Use of the compound or the pharmacologically acceptable salt thereof according to any one of to for producing a PDE4 inhibitor.
[18] Use of the compound or the pharmacologically acceptable salt thereof according to any one of to for manufacturing a therapeutic agent for diseases caused by PDE4.
Advantageous Effects of Invention
DESCRIPTION OF EMBODIMENTS
EXAMPLES
APCI: Atmospheric Pressure Chemical Ionization
DMF: N,N-dimethylformamide
DMSO: Dimethylsulfoxide
HOBT: 1-hydroxybenzotriazole
Me4t-butylXphos:
MIDA: N-methyliminodiacetic acid
MS: Mass spectrum
n: Normal
tert: tertiary
RuPhos: 2-Dicyclohexylphosphino-2′,6′-diisopropoxybiphenyl
(S)-Tol BINAP: (S)-(−)-2,2′-bis(di-para-tolylphosphino)-1,1′-binaphthyl
THF: tetrahydrofuran
XantPhos: 4,5-bis(Diphenylphosphino)-9,9-dimethyxanthene
WSCI: 1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride
Reference Example 1
5-Chloro-7-isopropyl-2-mercaptobenzoxazole
(a) 4-Chloro-2-isopropylphenol
(b) 4-Chloro-2-isopropyl-6-nitrophenol
(c) 2-Amino-4-chloro-6-isopropylphenol
(d) 5-Chloro-7-isopropyl-2-mercaptobenzoxazole
Reference Example 2
5-Chloro-7-methoxy-2-mercaptobenzoxazole
(a) 4-Chloro-2-methoxy-6-nitrophenol
(b) 2-Amino-4-chloro-6-methoxyphenol
(c) 5-Chloro-7-methoxy-2-mercaptobenzoxazole
Reference Example 3
7-Acetyl-5-chloro-2-mercaptobenzoxazole
(a) 3′-Amino-5′-chloro-2′-hydroxyacetophenone
(b) 7-Acetyl-5-chloro-2-mercaptobenzoxazole
Reference Example 4
5-Fluoro-7-methyl-2-mercaptobenzoxazole
(a) 4-Fluoro-2-methyl-6-nitrophenol
(b) 2-Amino-4-fluoro-6-methylphenol
(c) 5-Fluoro-7-methyl-2-mercaptobenzoxazole
Reference Example 5
5-Bromo-7-methyl-2-mercaptobenzoxazole
(a) 4-Bromo-2-methyl-6-nitrophenol
(b) 2-Amino-4-bromo-6-methylphenol
(c) 5-Bromo-7-methyl-2-mercaptobenzoxazole
Reference Example 6
5-Chloro-7-isopropoxy-2-mercaptobenzoxazole
(a) 4-Chloro-2-isopropoxyphenol
(b) 4-Chloro-2-isopropoxy-6-nitrophenol
(c) 2-Amino-4-chloro-6-isopropoxyphenol
(d) 5-Chloro-7-isopropoxy-2-mercaptobenzoxazole
Reference Example 7
5-Chloro-7-ethyl-2-mercaptobenzoxazole
(a) 4-Chloro-2-ethylphenol
(b) 4-Chloro-2-ethyl-6-nitrophenol
(c) 2-Amino-4-chloro-6-ethylphenol
(d) 5-Chloro-7-ethyl-2-mercaptobenzoxazole
Reference Example 8
5-Chloro-7-cyano-2-mercaptobenzoxazole
(a) 4-Chloro-2-cyano-6-nitrophenol
(b) 2-Amino-4-chloro-6-cyanophenol
(c) 5-Chloro-7-cyano-2-mercaptobenzoxazole
Reference Example 9
7-Bromo-5-chloro-2-mercaptobenzoxazole
(a) 2-Bromo-4-chloro-6-nitrophenol
(b) 2-Amino-6-bromo-4-chlorophenol
(c) 7-Bromo-5-chloro-2-mercaptobenzoxazole
Reference Example 10
7-Bromo-5-chloro-2-mercapto-4-(trifluoromethyl)benzoxazole
(a) 6-Bromo-4-chloro-2-nitro-3-(trifluoromethyl)phenol
(b) 2-Bromo-4-chloro-6-nitro-3-(trifluoromethyl)phenol
(c) 2-Amino-6-bromo-4-chloro-3-(trifluoromethyl)phenol
(d) 7-Bromo-5-chloro-2-mercapto-4-(trifluoromethyl)benzoxazole
Reference Example 11
7-Bromo-5-chloro-2-mercapto-6-(trifluoromethyl)benzoxazole
(a) 6-Amino-2-bromo-4-chloro-3-(trifluoromethyl)phenol
(d) 7-Bromo-5-chloro-2-mercapto-6-(trifluoromethyl)benzoxazole
Reference Example 12
7-Bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole
(a) 2-Bromo-4-chloro-5-(trifluoromethoxy)phenol
(b) 6-Bromo-4-chloro-2-nitro-3-(trifluoromethoxy)phenol
(c) 2-Amino-6-bromo-4-chloro-3-(trifluoromethoxy)phenol
(d) 7-Bromo-5-chloro-2-mercapto-4-(trifluoromethoxy)benzoxazole
Reference Example 13
7-Bromo-4,5-difluoro-2-mercaptobenzoxazole
(a) 6-Bromo-3,4-difluoro-2-nitrophenol
(b) 2-Amino-6-bromo-3,4-di fluorophenol
(c) 7-Bromo-4,5-difluoro-2-mercaptobenzoxazole
Reference Example 14
7-Bromo-5-chloro-6-fluoro-2-mercaptobenzoxazole
(a) 2-Bromo-4-chloro-3-fluorophenol
(b) 2-Bromo-4-chloro-3-fluoro-6-nitrophenol
(c) 6-Amino-2-bromo-4-chloro-3-fluorophenol
(d) 7-Bromo-5-chloro-6-fluoro-2-mercaptobenzoxazole
Reference Example 15
5-Chloro-2-mercapto-7-n-propylbenzoxazole
(a) 4-Chloro-2-nitro-6-n-propylphenol
(b) 2-Amino-4-chloro-6-n-propylphenol
(c) 5-Chloro-2-mercapto-7-n-propylbenzoxazole
Reference Example 16
7-Bromo-5-fluoro-2-mercaptobenzoxazole
(a) 2-Bromo-4-fluoro-6-nitrophenol
(b) 2-Amino-6-bromo-4-fluorophenol
(c) 7-Bromo-5-fluoro-2-mercaptobenzoxazole
Reference Example 17
7-Bromo-5-cyano-2-mercaptobenzoxazole
(a) 3-Bromo-4-hydroxy-5-nitrobenzonitrile
(b) 3-Amino-5-bromo-4-hydroxybenzonitrile
(c) 7-Bromo-5-cyano-2-mercaptobenzoxazole
Reference Example 18
7-Bromo-2-mercapto-5-methylbenzoxazole
(a) 2-Bromo-4-methyl-6-nitrophenol
(b) 2-Amino-6-bromo-4-methylphenol
(c) 7-Bromo-2-mercapto-5-methylbenzoxazole
Reference Example 19
7-Bromo-5-fluoro-2-mercapto-4-(trifluoromethyl)benzoxazole and 7-bromo-5-fluoro-2-mercapto-6-(trifluoromethyl)benzoxazole (mixture)
(a) 6-Bromo-4-fluoro-2-nitro-3-(trifluoromethyl)phenol, and 2-bromo-4-fluoro-6-nitro-3-(trifluoromethyl)phenol (mixture)
(b) 2-Amino-6-bromo-4-fluoro-3-(trifluoromethyl)phenol and 6-amino-2-bromo-4-fluoro-3-(trifluoromethyl)phenol (mixture)
(c) 7-Bromo-5-fluoro-2-mercapto-4-(trifluoromethyl)benzoxazole and 7-bromo-5-fluoro-2-mercapto-6-(trifluoromethyl)benzoxazole (mixture)
Reference Example 20
7-Bromo-5-chloro-4,6-difluoro-2-mercaptobenzoxazole
(a) 2-Bromo-4-chloro-3,5-difluoro-6-nitrophenol
(b) 2-Amino-6-bromo-4-chloro-3,5-difluorophenol
(c) 7-Bromo-5-chloro-4,6-difluoro-2-mercaptobenzoxazole
Reference Example 21
7-Bromo-4,5,6-trifluoro-2-mercaptobenzoxazole
(a) 2-Bromo-3,4,5-trifluoro-6-nitrophenol
(b) 2-Amino-6-bromo-3,4,5-trifluorophenol
(c) 7-Bromo-4,5,6-trifluoro-2-mercaptobenzoxazole
Reference Example 22
7-Bromo-2-mercapto-5-(trifluoromethyl)benzoxazole
(a) 2-Bromo-6-nitro-4-(trifluoromethyl)phenol
(b) 2-Amino-6-bromo-4-(trifluoromethyl)phenol
(c) 7-Bromo-2-mercapto-5-(trifluoromethyl)benzoxazole
Reference Example 23
7-Bromo-5-chloro-4-fluoro-2-mercaptobenzoxazole
(a) 2-Bromo-4-chloro-5-fluorophenol
(b) 2-Bromo-4-chloro-5-fluoro-6-nitrophenol
(c) 6-Amino-2-bromo-4-chloro-5-fluorophenol
(d) 7-Bromo-5-chloro-4-fluoro-2-mercaptobenzoxazole
Reference Example 24
7-Bromo-5-chloro-2-mercapto-4-methylbenzoxazole
(a) 2-Bromo-4-chloro-5-methylphenol
(b) 2-Bromo-4-chloro-5-methyl-6-nitrophenol
(c) 6-Amino-2-bromo-4-chloro-5-methylphenol
(d) 7-Bromo-5-chloro-2-mercapto-4-methylbenzoxazole
Reference Example 25
7-Bromo-5-fluoro-2-mercapto-4-(trifluoromethoxy)benzoxazole
(a) 6-Bromo-4-fluoro-2-nitro-3-(trifluoromethoxy)phenol
(b) 2-Amino-6-bromo-4-fluoro-3-(trifluoromethoxy)phenol
(c) 7-Bromo-5-fluoro-2-mercapto-4-(trifluoromethoxy)benzoxazole
Reference Example 26
7-Bromo-5-chloro-2-mercapto-6-methylbenzoxazole
(a) 2-Bromo-4-chloro-3-methylphenol
(b) 2-Bromo-4-chloro-3-methyl-6-nitrophenol
(c) 6-Amino-2-bromo-4-chloro-3-methylphenol
(d) 7-Bromo-5-chloro-2-mercapto-6-methylbenzoxazole
Reference Example 27
7-Bromo-5-chloro-2-mercapto-6-methoxybenzoxazole
(a) 2-Bromo-4-chloro-5-methoxyphenol
(b) 2-Bromo-4-chloro-3-methoxy-6-nitrophenol
(c) 6-Amino-2-bromo-4-chloro-3-methoxyphenol
(d) 7-Bromo-5-chloro-2-mercapto-6-methoxybenzoxazole
Reference Example 28
7-Bromo-5-chloro-4-cyano-2-mercaptobenzoxazole and 7-bromo-5-chloro-6-cyano-2-mercaptobenzoxazole (mixture)
(a) 4-Bromo-6-chloro-3-hydroxy-2-nitrobenzonitrile and 2-bromo-6-chloro-3-hydroxy-4-nitrobenzonitrile (mixture)
(b) 2-Amino-4-bromo-6-chloro-3-hydroxybenzonitrile and 4-amino-2-bromo-6-chloro-3-hydroxybenzonitrile (mixture)
(c) 7-Bromo-5-chloro-4-cyano-2-mercaptobenzoxazole and 7-bromo-5-chloro-6-cyano-2-mercaptobenzoxazole (mixture)
Reference Example 29
7-Bromo-5-chloro-2-mercapto-6-(trifluoromethoxy)benzoxazole
(a) 6-Bromo-4-chloro-2-nitro-5-(trifluoromethoxy)phenol
(b) 2-Amino-6-bromo-4-chloro-5-(trifluoromethoxy)phenol
(c) 7-Bromo-5-chloro-2-mercapto-6-(trifluoromethoxy)benzoxazole
Reference Example 30
5-Chloro-6-methoxy-7-methyl-2-mercaptobenzoxazole
(a) 1-Chloro-2,4-dimethoxy-3-methylbenzene
(b) 1-Chloro-2,4-dimethoxy-3-methyl-5-nitrobenzene
(c) 4-Chloro-3-methoxy-2-methyl-6-nitrophenol
(d) 6-Amino-4-chloro-3-methoxy-2-methylphenol
(e) 5-Chloro-6-methoxy-7-methyl-2-mercaptobenzoxazole
Reference Example 31
4-Bromo-6-chloro-2-mercaptobenzoxazole
(a) 2-Amino-3-bromo-5-chlorophenol
(b) 4-Bromo-6-chloro-2-mercaptobenzoxazole
Reference Example 32
5-Bromo-2-mercaptobenzoxazole
Reference Example 33
5-Cyano-7-methoxy-2-mercaptobenzoxazole
(a) 4-Hydroxy-3-methoxy-5-nitrobenzonitrile
(b) 3-Amino-4-hydroxy-5-methoxybenzonitrile
(c) 5-Cyano-7-methoxy-2-mercaptobenzoxazole
Reference Example 34
5-Chloro-6,7-dimethoxy-2-mercaptobenzoxazole
(a) 4-Chloro-2,3-dimethoxy-6-nitrophenol
(b) 6-Amino-4-chloro-2,3-dimethoxyphenol
(c) 5-Chloro-6,7-dimethoxy-2-mercaptobenzoxazole
Reference Example 35
5-Chloro-6-methyl-2-mercaptobenzoxazole
(a) 2-Amino-4-chloro-5-methylphenol
(b) 5-Chloro-6-methyl-2-mercaptobenzoxazole
Reference Example 36
5-Chloro-6-methoxy-2-mercaptobenzoxazole
Example 1
(S)-5-Chloro-7-isopropyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 2
(S)-5-Chloro-7-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 3
(S)-7-Acetyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
Example 4
meso-5-Chloro-2-(2,6-cis-dimethylpiperazin-1-yl)-7-methylbenzoxazole
Example 5
(S)-5-Fluoro-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 6
(S)-5-Bromo-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 7
(S)-5-Chloro-7-isopropoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 8
(S)-5-Chloro-7-ethyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 9
(S)-5-Chloro-7-ethoxycarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 10
(S)-5-Chloro-7-cyano-2-(2-methylpiperazin-1-yl)benzoxazole
Example 11
(S)-5-Chloro-7-ethyl-2-(2-isopropylpiperazin-1-yl)benzoxazole
Example 12
(S)-5-Chloro-7-ethyl-2-(2-isobutylpiperazin-1-yl)benzoxazole
Example 13
(S)-2-(2-n-Butylpiperazin-1-yl)-5-chloro-7-ethylbenzoxazole
Example 14
(S)-5-Chloro-7-ethyl-2-(2-ethylpiperazin-1-yl)benzoxazole
Example 15
(S)-5-Chloro-7-hydroxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-ethoxycarbonylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-carboxybenzoxazol-2-yl)-3-methylpiperazine
(c) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(hydroxymethyl)benzoxazol-2-yl)-3-methylpiperazine
(d) (S)-5-Chloro-7-hydroxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 16
(S)-5-Chloro-2-2-methylpiperazin-1-yl)-7-(thiophen-3-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chlorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiophen-3-yl)benzoxazole
Example 17
(S)-5-Chloro-7-(furan-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(furan-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(furan-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 18
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiophen-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiophen-2-yl)benzoxazole
Example 19
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-phenylbenzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-phenylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-phenylbenzoxazole
Example 20
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyrrolidin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyrrolidin-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyrrolidin-1-yl)benzoxazole
Example 21
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(morpholin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(morpholin-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(morpholin-1-yl)benzoxazole
Example 22
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(piperidin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(piperidin-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(piperidin-1-yl)benzoxazole
Example 23
(S)-5-Chloro-7-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(furan-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 24
(S)-5-Chloro-7-(cyclopentylamino)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclopentylamino)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(cyclopentylamino)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 25
(S)-5-Chloro-7-diethylamino-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(diethylamino)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-diethylamino-2-(2-methylpiperazin-1-yl)benzoxazole
Example 26
(S)-5-Chloro-7-dimethylamino-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(dimethylamino)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-dimethylamino-2-(2-methylpiperazin-1-yl)benzoxazole
Example 27
(S)-5-Chloro-7-cyclopropyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-cyclopropylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-cyclopropyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 28
(S)-5-Chloro-7-(cyclopentyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclopentyloxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(cyclopentyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 29
(S)-5-Chloro-7-ethoxy-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-ethoxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-ethoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 30
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-n-propoxybenzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-n-propoxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-n-propoxybenzoxazole
Example 31
(S)-5-Chloro-7-cyclopentyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-cyclopentylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-cyclopentyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 32
(S)-7-n-Butyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-n-butyl-5-chlorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-7-n-Butyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
Example 33
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-′7-(1H-pyrazol-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 34
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(oxazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 35
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
(a)(S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 36
(S)-5-Chloro-7-(1H-imidazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-imidazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(1H-imidazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 37
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-4-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-4-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-4-yl)benzoxazole
Example 38
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-5-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-5-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-5-yl)benzoxazole
Example 39
(S)-5-Chloro-7-(5-methylfuran-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-methylfuran-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-methylfuran-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 40
(S)-5-Chloro-7-(4-methyl-1H-pyrazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4-methyl-1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(4-methyl-1H-imidazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 41
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 42
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-3-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-3-yl)benzoxazole
Example 43
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-4-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-4-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-4-yl)benzoxazole
Example 44
(S)-5-Chloro-7-cyclohexyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-cyclohexylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-cyclohexyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 45
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2H-1,2,3-triazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2H-1,2,3-triazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(2H-1,2,3-triazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 46
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-1,2,4-triazol-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-1,2,4-triazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(1H-1,2,4-triazol-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 47
(S)-5-Chloro-7-isobutyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-isobutylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-isobutyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 48
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-hydroxymethylphenyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-hydroxymethylphenyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-hydroxymethylphenyl)benzoxazole
Example 49
(S)-5-Chloro-7-(1-methyl-1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)-benzoxazole
a (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1-methyl-1H-imidazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(1-methyl-1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)-benzoxazole
Example 50
(S)-5-Chloro-7-(1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)benzox azole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4,4,5,5-tetramethyl-1,3,2-dioxaboran-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-imidazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-7-(1H-imidazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 51
(S)-5-Chloro-7-(cyclohexylmethyl)-2-(2-methylpiperazin-1-yl)-benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclohexylmethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(cyclohexylmethyl)-2-(2-methylpiperazin-1-yl)-benzoxazole
Example 52
(S)-5-Chloro-7-(cyclohexyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-hydroxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclohexyloxy)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-7-(cyclohexyloxy)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 53
(S)-5-Chloro-7-(cyclopropylmethoxy)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(cyclopropylmethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(cyclopropylmethoxy)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 54
(S)-5-Chloro-7-(isothiazole-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(isothiazole-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(isothiazole-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 55
(S)-5-Chloro-7-(5-hydroxymethylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-hydroxymethylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-hydroxymethylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 56
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyrimidin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyrimidin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyrimidin-2-yl)benzoxazole
Example 57
(S)-5-Chloro-7-(5-chlorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-chlorothiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-chlorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 58
(S)-5-Chloro-7-(5-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-chloropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 59
(S)-5-Chloro-7-(4-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
a (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4-chloropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(4-chloropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 60
(S)-5-Chloro-7-(6-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(6-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(6-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 61
(S)-5-Chloro-7-(3-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(3-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 62
(S)-5-Chloro-7-(5-cyanothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-cyanothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-cyanothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 63
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(5-methylthiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-methylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(5-methylthiazol-2-yl)benzoxazole
Example 64
(S)-5-Chloro-7-(2-chlorothiophen-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
a (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-chlorothiophen-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(2-chlorothiophen-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 65
(S)-5-Chloro-7-(5-carbamoylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-carbamoylthiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-carbamoylthiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 66
(S)-5-Chloro-7-(3-cyanopyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-cyanopyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(3-cyanopyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 67
(S)-5-Chloro-7-(5-fluorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-fluorothiophen-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-fluorothiophen-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazol
Example 68
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(3-methylpyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-methylpyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(3-methylpyridin-2-yl)benzoxazol
Example 69
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-methylthiazol-4-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-methylthiazol-4-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-methylthiazol-4-yl)benzoxazole
Example 70
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-phenoxybenzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-phenoxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-phenoxybenzoxazole
Example 71
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-oxo-pyrrolidin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-oxo-pyrrolidin-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyrrolidin-1-yl)benzoxazole
Example 72
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-oxo-oxazolidin-3-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-oxo-oxazolidin-3-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(2-oxo-oxazolidin-3-yl)benzoxazole
Example 73
(S)-5-Chloro-7-(5-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-fluoropyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-fluoropyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 74
(S)-5-Chloro-7-(5-chlorothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-chlorothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-chlorothiazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 75
(S)-7-Benzyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-benzyl-5-chloro-benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-7-Benzyl-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
Example 76
(S)-5-Chloro-7-(5-(hydroxymethyl)thiazol-4-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-(hydroxymethyl)thiazol-4-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(5-(hydroxymethyl)thiazol-4-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 77
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yloxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yloxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yloxy)benzoxazole
Example 78
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(5-nitrothiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(5-nitrothiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(5-nitrothiazol-2-yl)benzoxazole
Example 79
(S)-5-Chloro-7-(3-methoxypyridin-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-methoxypyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 80
5-Chloro-2-((S)-2-methylpiperazin-1-yl)-7-(tetrahydrofuran-2-yl)benzoxazole
(a) (3 S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(tetrahydrofuran-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) 5-Chloro-24(S)-2-methylpiperazin-1-yl)-7-(tetrahydrofuran-2-yl)benzoxazole
Example 81
(S)-5-Chloro-7-(4-fluorophenyl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4-fluorophenyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-(4-fluorophenyl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 82
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
Example 83
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole
Example 84
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole
Example 85
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-6-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-6-(trifluoromethyl)benzoxazole
Example 86
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 87
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 88
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole
Example 89
(S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-4,5-difluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(4,5-difluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 90
(a) (S)-1-tert-Butoxycarbonyl-4-(4,5-difluoro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 91
(S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(4,5-difluoro-7-(1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-4,5-Difluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 92
(S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-fluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 93
(S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-fluoro-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 94
(S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-fluoro-7-(1H-pyrazol-1-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-6-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 95
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-n-propylbenzoxazole
Example 96
(S)-5-Chloro-7-dimethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-dimethylaminocarbonylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-dimethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 97
(S)-5-Chloro-7-diethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 98
(S)-5-Chloro-7-hydroxyaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 99
(S)-5-Chloro-7-carboxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 100
(S)-5-Chloro-7-methylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 101
(S)-5-Chloro-7-ethylaminocarbonyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 102
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-fluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 103
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 104
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 105
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1,2,4-oxadiazol-3-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-cyanobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-hydroxycarbamidoyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1,2,4-oxadiazol-3-yl)benzoxazole
Example 106
(S)-5-Chloro-7-(4,5-dihydro-oxazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(2-hydroxyethyl)aminocarbonyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(4,5-dihydro-oxazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-7-(4,5-dihydro-oxazol-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 107
(S)-5-Chloro-7-(methoxymethyl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-methoxy methylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-7-methoxymethyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 108
(S)-5-Chloro-7-(isoxazol-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-acetyl-5-chlorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(3-(dimethylamino)acryloyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-7-(isoxazol-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 109
(S)-5-Chloro-7-(isoxazol-5-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 110
(S)-7-Bromo-5-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
Example 111
(S)-5-Cyano-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-cyanobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-cyano-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Cyano-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 112
(S)-5-Cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 113
(S)-5-Cyano-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 114
(S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-methylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 115
(S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 116
(S)-5-methyl-2-(2-methylpiperazin-1-yl)-7-(oxazol-2-yl)benzoxazole
Example 117
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
Example 118
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole
Example 119
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole
Example 120
(S)-5-Chloro-4,6-difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4,6-difluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4,6-difluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-4,6-difluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 121
(S)-5-Chloro-4,6-difluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 122
(S)-4,5,6-Trifluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-4,5,6-trifluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(4,5,6-trifluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-4,5,6-Trifluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 123
(S)-4,5,6-Trifluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzox azole
Example 124
(S)-4,5,6-Trifluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 125
(S)-2-(2-Methylpiperazin-1-yl)-7-(pyridin-2-yl)-5-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(7-(pyridin-2-yl)-5-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-2-(2-Methylpiperazin-1-yl)-7-(pyridin-2-yl)-5-(trifluoromethyl)benzoxazole
Example 126
(S)-2-(2-Methylpiperazin-1-yl)-7-(thiazol-2-yl)-5-(trifluoromethyl)benzoxazole
Example 127
(S)-2-(2-Methylpiperazin-1-yl)-7-(oxazol-2-yl)-5-(trifluoromethyl)benzoxazole
Example 128
(S)-5-Chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-fluorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-fluoro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 129
(S)-5-Chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 130
(S)-5-Chloro-4-fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 131
(S)-5-Chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-methylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 132
(S)-5-Chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 133
(S)-5-Chloro-4-methyl-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 134
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-fluoro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-fluoro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 135
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 136
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole
Example 137
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-methylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-methyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 138
(S)-5-Chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 139
(S)-5-Chloro-6-methyl-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 140
(S)-5-Chloro-6-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-methoxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-methoxy-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-6-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 141
(S)-5-Chloro-6-methoxy-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 142
(S)-5-Chloro-6-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-cyanobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-6-cyano-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-6-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 143
(S)-5-Chloro-4-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-cyanobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-cyano-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-4-cyano-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 144
(S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-fluoro-6-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-fluoro-6-trifluoromethyl-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Fluoro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethyl)benzoxazole
Example 145
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(methylsulfonyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(methylsulfonyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(methylsulfonyl)benzoxazole
Example 146
(S)-5-Chloro-4-iodo-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 147
(S)-5-Chloro-6-iodo-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benz oxazole
Example 148
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-phenyl-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-iodo-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-phenyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-phenyl-7-(pyridin-2-yl)benzoxazole
Example 149
(S)-5-Chloro-4-cyclopropyl-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-cyclopropyl-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-cyclopropyl-7-(pyridin-2-yl)benzoxazole
Example 150
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-(methylthio)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(methylthio)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-(methylthio)-7-(pyridin-2-yl)benzoxazole
Example 151
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-(methylsulfonyl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(methylsulfonyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-4-(methylsulfonyl)-7-(pridin-2-yl)benzoxazole
Example 152
(S)-6-Bromo-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(6-bromo-5-chloro-7-(pyridin-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-6-Bromo-5-chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazol
Example 153
(S)-5-Chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-hydroxybenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-methoxybenzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)benzoxazole
Example 154
(S)-5-Chloro-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 155
(S)-5-Chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-4-methoxy-7-(thiazol-2-yl)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-5-Chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)benzoxazole
Example 156
(S)-5-Chloro-4-methoxy-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)benzoxazole
Example 157
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(c) (R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 158
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 159
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethoxy)benzoxazole
Example 160
(S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-6-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-6-(trifluoromethoxy)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-6-(trifluoromethoxy)benzoxazole
Example 161
(S)-5-Chloro-6-methoxy-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 162
(S)-5-Chloro-6-hydroxy-7-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 163
(S)-4-Bromo-6-chloro-2-(2-methylpiperazin-1-yl)benzoxazole
Example 164
(S)-6-Chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(4-bromo-6-chlorobenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-6-Chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 165
(R)-6-Chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(4-bromo-6-chlorobenzoxazol-2-yl)-3-methylpiperazine
(b) (R)-6-Chloro-4-(furan-2-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 166
(S)-6-Chloro-2-(2-methylpiperazin-1-yl)-4-(1H-pyrazol-1-yl)benzoxazole
Example 167
(S)-5-Bromo-2-(2-methylpiperazin-1-yl)benzoxazole
Example 168
(S)-5-Cyano-7-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 169
(S)-5-Chloro-6,7-dimethoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 170
(S)-5-Chloro-6-methyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 171
(S)-5-Chloro-6-methoxy-2-(2-methylpiperazin-1-yl)benzoxazole
Example 172
(S)-7-Methyl-5-(pyrrolidin-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-bromo-7-methylbenzoxazol-2-yl)-3-methylpiperazine
(b) (S)-7-Methyl-5-(pyrrolidin-1-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 173
(S)-7-Methyl-5-(thiophen-3-yl)-2-(2-methylpiperazin-1-yl)benzoxazole
Example 174
(R)-5-Chloro-7-ethyl-2-(2-methylpiperazin-1-yl)benzoxazole
Example 175
5-Chloro-2-(piperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) 1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)piperazine
(b) 1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)piperazine
(c) 5-Chloro-2-(piperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 176
(R)-5-Chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine
(b) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine
(c) (R)-5-Chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 177
(S)-5-Chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine
(b) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazol-2-yl)-2-methylpiperazine
(c) (S)-5-Chloro-2-(3-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethoxy)benzoxazole
Example 178
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(7-bromo-5-chloro-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(c) (S)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(pyridin-2-yl)-4-(trifluoromethyl)benzoxazole
Example 179
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole
(a) (S)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(thiazol-2-yl)-4-(trifluoromethyl)benzoxazole
Example 180
(R)-5-Chloro-2-(2-methylpiperazin-1-yl)=7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole
(a) (R)-1-tert-Butoxycarbonyl-4-(5-chloro-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazol-2-yl)-3-methylpiperazine
(b) (R)-5-Chloro-2-(2-methylpiperazin-1-yl)-7-(1H-pyrazol-1-yl)-4-(trifluoromethyl)benzoxazole
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 Test Example 1
Evaluation of PDE4 Inhibition
Inhibition rate (%)={1−(Numeric value from the addition of each sample−Blank value)/(Control value−Blank value)}×100Example 1 87 Example 2 23 Example 3 50 Example 4 18 Example 5 25 Example 6 36 Example 7 59 Example 8 79 Example 9 50 Example 36 10 Example 26 11 Example <10 12 Example <10 13 Example 37 14 Example 21 15 Example 75 16 Example 84 17 Example 76 18 Example 76 19 Example 71 20 Example 59 21 Example 40 22 Example 95 23 Example 27 24 Example 53 25 Example 61 26 Example 85 27 Example 81 28 Example 63 29 Example 61 30 Example 51 31 Example 62 32 Example 93 33 Example 89 34 Example 96 35 Example 39 36 Example 98 37 Example 68 38 Example 42 39 Example 68 40 Example 93 41 Example 66 42 Example 61 43 Example 64 44 Example 87 45 Example 29 46 Example 35 47 Example 53 48 Example 17 49 Example 62 50 Example 12 51 Example 57 52 Example 50 53 Example 92 54 Example 80 55 Example 87 56 Example 54 57 Example 77 58 Example 71 59 Example 63 60 Example 81 61 Example 65 62 Example 87 63 Example 73 64 Example 83 65 Example 57 66 Example 70 67 Example 38 68 Example 65 69 Example 38 70 Example 30 71 Example 28 72 Example 93 73 Example 83 74 Example 45 75 Example 73 76 Example 30 77 Example 58 78 Example 53 79 Example 42 80 Example 68 81 Example 94 82 Example 92 83 Example 95 84 Example 26 85 Example 91 86 Example 96 87 Example 95 88 Example 88 89 Example 96 90 Example 89 91 Example 71 92 Example 95 93 Example 62 94 Example 71 95 Example <10 96 Example 10 97 Example <10 98 Example <10 99 Example 16 100 Example 27 101 Example 85 102 Example 96 103 Example 88 104 Example 61 105 Example 42 106 Example 66 107 Example 66 108 Example 61 109 Example 57 110 Example 83 111 Example 94 112 Example 71 113 Example 77 114 Example 91 115 Example 80 116 Example 88 117 Example 99 118 Example 91 119 Example 41 120 Example 62 121 Example 79 122 Example 95 123 Example 46 124 Example 91 125 Example 95 126 Example 90 127 Example 79 128 Example 97 129 Example 83 130 Example 90 131 Example 94 132 Example 92 133 Example 88 134 Example 99 135 Example 90 136 Example 33 137 Example 86 138 Example 39 139 Example 35 140 Example 77 141 Example 86 142 Example 94 143 Example 41 144 Example 80 145 Example 95 146 Example 53 147 Example 94 148 Example 91 149 Example 91 150 Example 76 151 Example 68 152 Example 93 153 Example 39 154 Example 96 155 Example 91 156 Example 41 157 Example 88 158 Example 57 159 Example 86 160 Example 19 161 Example 35 162 Example 52 163 Example 75 164 Example 31 165 Example 71 166 Example 16 167 Example 13 168 Example 22 169 Example 15 170 Example 14 171 Example <10 172 Example 35 173 Example 21 174 Example 96 175 Example 91 176 Example 93 177 Example 33 178 Example 79 179 Example 43 180