Novel vitamin D analogues

Abstract

This invention relates to vitamin D analogues represented by the general formula I ##STR1## in which formula X stands for hydrogen, lower alkyl, halogen or hydroxy; Y stands for hydrogen or hydroxy; R.sup.1 and R.sup.2, which may be the same or different, stand for lower alkyl, optionally substituted with halogen or hydroxy with the proviso that R.sup.1 and R.sup.2 cannot both be methyl when X is other than lower alkyl, or, taken together with the carbon atom numbered 25, R.sup.1 and R.sup.2 can form a saturated or unsaturated C.sub.3 -C.sub.9 carbocyclic ring which may optionally be substituted at any possible position(s) with lower alkyl, halogen or hydroxy; R.sup.3 stands for hydrogen or lower alkyl; R.sup.4 and R.sup.5 represent either each hydrogen, or when taken together constitute a bond, with the result that a double bond connects carbon atoms numbered 22 and 23; and bioreversible derivatives thereof. The compounds of the invention have a favorable therapeutic index and are particularly useful in the treatment of human and veterinary disorders which are characterized by abnormal cell proliferation and/or cell differentiation.

Dependencies are inferred from the claim text.