GB978725A - Novel steroid compounds and processes for their perparation - Google Patents

Abstract

The invention comprises 17a -hydroxy-pregn-4-ene-3, 11, 20-trione derivatives having the formula: <FORM:0978725/C1/1> in which "R" represents a hydrogen atom or an acyl group derived from an organic carboxylic acid having from 1-18 carbon atoms and processes for the preparation thereof in which a compound of the formula: <FORM:0978725/C1/2> where R1 and R11, which may be the same or different, each represents an hydrogen atom or an alkyl group having from 1-6 carbon atoms and n is 0 or 1 is subjected to catalytic hydrogenation to eliminate the double bond at the 16-17 position thus forming the corresponding 3-cyclic ketal of 18-nor-pregna-3, 11, 20-trione which is then hydroperoxygenated at the 17-position by the action of oxygen in the presence of an alkali metal alcoholate, thus forming the corresponding 3-cyclic ketal of 17a -hydroperoxy -18- nor-pregna-3, 11, 20-trione, which is reduced to form the 3-cyclic ketal of 17a -hydrohydroxy-18-nor-pregna-3, 11, 20-trione, the protected 3-keto group of which is then liberated by acid hydrolysis to form 17a -hydroxy-18-norpregna-3, 11, 20-trione, which is brominated to form 4#x-bromo-17a -hydroxy-18-nor-pregna-3, 11, 20-trione and the latter is dehydrobrominated thus forming 17a -hydroxy-18-nor-pregn-4-ene -3, 11, 20-trione, which is finally subjected to either treatment with a microbiological hydroxylating agent or to halogenation followed by acyloxylation and saponification, to yield 17a -, 21-dihydroxy -18- nor-pregn-4-ene-3, 11, 20-trione which may be esterified if desired to form the corresponding 21-ester. The hydroperoxy compound may be formed in the presence of potassium t-butylate, whilst 21-hydroxylation may be effected using a culture of Colletotrichum lindemuthianum or by iodinating to form a 21-diiodo derivative followed by acyloxylation using an alkali metal acylate and saponification. Specification 978,725 is referred to.