title: 17 alpha-ethynyl-17 beta-hydroxy-10 alpha-estr-4-en-3-one.
mesh_terms: D003270:Contraceptive Agents / Q000138:chemical synthesis*; D009640:Norethindrone / Q000138:chemical synthesis*
chemical_list: D003270:Contraceptive Agents; D009640:Norethindrone