21-substituted progesterone derivatives as new antiprogestational agents

The present invention provides compounds of general formula (I) wherein R 1 is -OCH 3, -SCH 3, -N (CH 3) 2, -NHCH 3, -CHO, -COCH 3, and -CHOHCH 3; R2 is selected from halo, alkyl, acyl, hydroxy, alkyloxy, acylamino, alkylcarbonyl, cyclohexyl, S-alkyl or S-acyl, R3 is alkyl, hydroxy, alkynyl or acyl alkyloxy group; R4 is hydrogen or alkyl; and X is = O or = N-OR5, wherein R5 is hydrogen or alkyl. The compounds include, for example, progenitor antagonizing agents, such as, for the treatment of endoscopy, for treating endometrial cancer, for treatment of dysmenorrhoea, for treatment of endocrine bronchospasm, for the treatment of uterine fibroids, for inhibition of uterine metastasis, for birth and for pregnancy. The invention also provides the compounds for the manufacture of pharmaceutical compositions. ŕ