摘要:
New 25-carboxylic acid derivatives of general formula I, ##STR1## R.sup.19 and R.sup.19a each mean a hydrogen atom or together form an exocyclic methylene group,R.sup.21 and R.sup.21a independently of one another mean a hydrogen atom, a chlorine or fluorine atom, an alkyl group with 1 to 4 carbon atoms, together a methylene group, together with quaternary carbon atom 20 mean a 3-7 membered, saturated or unsaturated carboxylic ring,Y preferably means a derivatized carboxyl radical, and the other substituents have the meanings indicated in the description as well as process for their production, are described.The new compounds have vitamin D activity as well as proliferation-inhibiting and cell-differentiating effects and are suitable for the production of pharmaceutical agents.