17 alpha -cyanomethylestra-4,9-dien derivatives and pharmaceutical compositions containing same

The 17 alpha -cyanomethylestra-4,9-diene derivative compounds are of formula I: I wherein R1 is an alkyl group having from 1 to 2 carbon atoms; R2 is an alkyl group with 1 to 10 carbon atoms, an acyl group with 1 to 10 carbon atoms or a trialkylsilyl group; and R3 is an oxygen atom or a R-O-N group, wherein R is a hydrogen atom, an acyl group with 1 to 10 carbon atoms, an alkyl group with 1 to 10 carbon atoms, a sulfamoyl group, an alkylsilyl group or a trialkylsilyl group. These compounds, particularly in combination with at least one suitable estrogen, are suitable for treatment of endometrioses or gestagen-dependent tumors and for hormonal contraception and climacteric hormone replacement therapy (HRT). Processes for making the new steroids are described as well as methods of making the pharmaceutical compositions containing them.