Steroids and process for their manufacture
Реферат: The invention comprises a compound of the formula <FORM:0893577/IV (b)/1> wherein R1 represents a free or functionally converted hydroxyl group together with a hydrogen atom or a free or protected oxo group R2 represents two hydrogen atoms, an oxo group or an enol acylate grouping derived therefrom and R3 represents hydrogen or an alkyl group (1-10 carbon atoms), and derivatives thereof having a double bond in the 4 : 5, 5 : 6, and/or 14 : 15 position and a process for the preparation thereof wherein a compound of the formula <FORM:0893577/IV (b)/2> or a derivative thereof unsaturated in the 4 : 5, 5 : 6, and/or 14 : 15 position, containing in 3-position a free or functionally converted hydroxyl group or a protected oxo group is condensed with carbonic acid ester in the presence of an alkaline condensing agent, the resulting b -keto ester, if desired, after hydrogenation of any 14 : 15 double bond present, converted to a 16-enol derivative, in the latter the substituent in 16-position hydrogenolytically removed and at the same time the 16,17-double bond hydrogenated and, if desired, any functionally converted hydroxy, oxo or carboxy group is liberated. The condensation with carbonic acid esters, e.g. diethyl carbonate may be effected in the presence of an alkaline condensing agent, e.g. alkali metal alcoholates, hydrides or amides. Hydrogenation of the 14 : 15-double bond may be effected using a palladium catalyst on charcoal, calcium carbonate, barium sulphate or zinc carbonate. The enol esters are produced with acid anhydrides or acid halides. Hydrogenolysis of the enol derivative is effected in neutral or weakly alkaline conditions in the presence of noble metal catalysts or Raney nickel. Subsequently the enol ether group between the 18 and 11 positions may be split by known methods. Specification 814,711 is referred to.
New í¸-11ª‡-hydroxy-steroids and process for their manufacture
Номер патента: GB982922A. Автор: . Владелец: Ciba AG. Дата публикации: 1965-02-10.