GB912200A - Improvements in or relating to methods of producing 3-keto-í~,-10(ª-)-methyl steroids - Google Patents

Abstract

3-Keto-D 4,6-10a -methyl-steroids are prepared by subjecting 3-keto-D 4,7-10a -methyl-steroids to isomerisation in a solvent which contains less than 1% by weight of water and which, if it is saturated with hydrofluoric acid gas at 18 DEG C. has an electrical conductivity of at least 10-4 Mhos-preferably exceeding 10-2 Mhos, while the isomerisation in the solvent occurs under the influence of a hydrogen halide present in the solvent to at least 60% of saturation value-preferably saturated, at the reaction temperature. Suitable solvents are primary and secondary alcohols such as methyl, ethyl, propyl, butyl, pentyl, hexyl, propyl-2, butyl-2 and -3 and pentyl-2 and -3 alcohols. The steroid reactant may contain an a - or b -methyl group at C13, and at C17 a saturated or unsaturated aliphatic hydrocarbon substituent such as a 17-side chain similar to that of ergosterol, a 17-side chain formed by the oxidation of such a side chain e.g. a chain formed by ozonolysis such as a radical of the formula -CH(CH3)-CHO, or a 17-side chain containing an aldehyde or carboxy substituent. Furthermore, one or more of the hydrogen atoms at positions 9, 11, 16 and/or 17 may be replaced by functional groups, e.g. by hydroxy, esterified hydroxy, alkyl, acyl, hydroxylated acyl, keto or halogen substituents. In the examples D 4,6,22-luminstatrien-3-one is prepared from D 4,7,22-lumistatrien-3-one, and D 4,6,22-pyrostatrien-3-one is prepared from D 4,7,22-pyrostatrien-3-one. The conversion of D 7 - 10a - methyl - progesterone into D 6-10a -methyl-progesterone is also referred to. 10a -Methyl-progesterone (lumiprogesterone) is prepared by hydrogenating the D 6-double bond of 3-keto-D 3,6-lumisterol and then degrading the side chain by usual methods. 3 - Methoxy-D 3,5,7,22-lumistatetraene is prepared by isomerising D 4,7,22-lumistatriene-3-one with hydrogen chloride in propanol-2 up to 20% saturation concentration in the propanol-2. D 4,7,22-Pyrostatrien-3-one is prepared by the Oppenauer oxidation of pyrocalciferol.