13-ALKYL-11BETA-PHENYLGONANES

摘要

This invention relates to 13-alkyl-11beta-phenyl-gonanes of the following general Formula I <IMG> (I). in which Z is =O or =N-OH, R1 is a cyclic or heterocyclic radical, or C2-10-alkenyl, R2 is .alpha. or .beta. -CH3 or -C2H5 and R3/R4 are various organic groups. The compounds of general Formula I have a strong affinity for the gestagen receptor, without themselves developing gestagen activity. They are competitive antagonists of the progesterone (anti-gestagens); since they displace from the receptor the progesterone necessary for maintaining pregnancy, they are suitable for triggering abortions and for inducing birth.