title: [Antiprogestational steroids: synthesis of 7 alpha- and 7 beta-methyl-a-nor-5 alpha-androstane-2 alpha, 17 alpha-DI-ethynyl-2 beta,17 beta-diol].
mesh_terms: D000818:Animals; D003280:Contraceptives, Oral, Synthetic / Q000138:chemical synthesis*; D009635:Norandrostanes / Q000138:chemical synthesis*; D051381:Rats
chemical_list: D003280:Contraceptives, Oral, Synthetic; D009635:Norandrostanes; C052065:7-methyl-A-norandrostane-2,17-diethynyl-2,17-diol