VITAMIN-D AMIDE DERIVATIVES

摘要

Compound of general formula (I) where R1 and R2, which may be the same or different, each represent a hydrogen atom or an aliphatic, cycloaliphatic, araliphatic or aryl group or together with the nitrogen atom to which they are attached form a heterocyclic group; R3 represents a methyl group having .alpha.- or .beta.-configuration; one of Ra and Rb represents a hydroxy group or protected hydroxy group and the other represents a hydrogen atom; Y represents a valence bond or an alkylene group containing up to 3 carbon atoms; and A= represents a cyclohexylidene moiety characteristic of the A-ring of a 1.alpha.-hydroxylated vitamin D or analogue thereof. Active compounds of the invention exhibit separation of cell modulating and calcaemic activities coupled with enhanced duration of activity.