19 nor pregneno substituted Derivatives, their use and Pharmaceutical compositions containing them and birth control.

摘要

Derivative 19 nor pregneno alternative formula (I),where: R1, R2, R3, R4 and R6 are each independently hydrogen or a (C1-C6) alkyl; R5 is hydrogen, a (C1-C6) alkyl, a -COR7 group where R7 is a (C1- C6) alkyl; n is zero or one; and X is oxygen or a hydroxyimino group, provided that when n = 0, at least two of R1, R2, R3 and R4 are different from hydrogen and that when n = 1, R3 and R4 are not simultaneously hydrogen; and pharmaceutical compositions containing them. These compounds are excellent progestogens and have no residual androgenic activity.