摘要 |
A steroid with a 17-spiromethylene lactone group having formula I <CHEM> wherein R1 is O, (H,H), (H,OR), or NOR, R being selected from H, (1-6C) alkyl and (1-6C) acyl; R2 is H, (1-6C) alkyl optionally substituted by a halogen, (2-6C) alkenyl optionally substituted by a halogen, (2-6C) alkynyl optionally substituted by a halogen, or halogen; R2' is H; or R2' together with R2 is a (1-6C) alkylidene group or a (2-6C) alkenylidene group; or R2' together with R3 is a bond; R3 is H if not together with R2' a bond; R4 is (1-6C) alkyl; one of R5 and R6 is hydrogen and the other is hydrogen or (1-6C) alkyl; X is (CH2)n or (CnH2n-2) wherein n is 2 or 3, which is optionally substituted with hydroxy, halogen, (1-6C) alkyl, (1-6C) acyl, (7-9C) phenylalkyl, the phenyl group of which may be substituted with (1-6C) alkyl, (1-6C) alkoxy, hydroxy or halogen; Y is O or (H,OH); and the dotted lines indicate optional bonds, at least one of bonds 4-5, 5-10, and 9-10 being a double bond. The steroids of the invention have progestational activity and can be used as contraceptives. |