(3,5)-cyclo-(6)-alkoxy-cholestenes - useful as intermediates for (25)-hydroxy-cholesterol derivs.

摘要

3 alpha, 5 alpha-Cyclo-6 beta-alkoxy-delta22-cholestene derivs. of formula (I) are new: (where R is 1-6C alkyl; X is CHCH2CHe2D or D is O- or R4CO2; R1-R3 are H or Me; and R4 is 1-6C alkyl, Ph, PhCH2 or PhCH2CH2). (I) are used as intermediates for 25-hydroxycholesterol derivs. and therefore 25-hydroxy-Vitamin D metabolites and their analogues. In an example, 3 alpha, 5 alpha-cyclo-6 beta-methoxy-25-hydroxy-26,27-bisnorcholest-22-ene-was obtd. by reacting 3 alpha, 5 alpha-cyclo-6 beta-methoxybisnorcholanaldehyde with the prod. of methyltriphenylphosphonium bromide, n-BuLi and ethylene oxide.