17-Hydroxy-19-nor-17α-pregn-5(10)-en-20-yn-3-one; 17α-Ethinyl-17β-hydroxy-Δ5(10)-estren-3-one; 17α-Ethynyl-17-hydroxy-5(10)-estren-3-one; 17α-Ethynyl-17β-hydroxy-5(10)-estrene-3-one; 17α-Ethynyl-17β-hydroxy-Δ5(10)-estren-3-one;,17-hydroxy-19-nor-17alpha-pregn-5(10)-en-20-yn-3-one,"The compound is a progestin used in Enovid, an oral contraceptive, also used in the treatment of endometriosis and hypermenorrhea.",Norethindrone API