1 alpha ,25-Dihydroxylated vitamin D2 compounds and intermediates in the preparation thereof

摘要

The invention provides 1 alpha ,25-dihydroxyvitamin D2 derivatives and acylates thereof of formulae IMAGE where each of R1, R2 and R3 is hydrogen or acyl and X is alkyl or aryl which may be isotopically labelled. When the C-24-methyl substituent in the 5, 6- cis compound has the S-configurationed and X is methyl, not all R1, R2 and R3 are hydrogen. The compounds find ready application as substitutes for vitamin D3 or D2 or various applications to the correction of disorders involving calcium metabolism and associated bone disease.