16,17-carbocyclic condensed steroid compounds having selective estrogenic activity

The invention discloses a steroid compound having the formula (1), wherein dotted bonds represent optional double bonds; R 6 is H, ═CH 2 , or —CH 3 , or —CH 2 —CH 3 ; R 7 is H, C 1-4 -alkyl, C 2-5 alkenyl or C 2-5 -alkynyl, wherein the alkyl, alkenyl or alkynyl group may be substituted with 1 to 3 halogen atoms independently chosen from the group of fluorine or chlorine atoms; R 11 is H, C 1-4 -alkyl, C 2-4 -alkenyl, C 2-4 -alkynyl or C 1-4 -alkylidene, wherein the alkyl, alkenyl, alkynyl or alkylidene group may be substituted with 1-3 halogen atoms independently chosen from the group of fluorine or chlorine atoms; E represents together with carbon atoms 16 and 17 of the steroid skeleton a four to seven-membered ring, said ring being α and in cis-configuration with respect to the steroid skeleton, optionally comprising one or two endocyclic bonds; or a prodrug thereof. Such compounds can be used in therapy and for methods for selective modification of the activity of estrogen receptors.