<unk> , also known as 17α-ethynyl-3-desoxy-19-nortestosterone or as 17α-ethynylestr-4-en-17β-ol, is a synthetic estrane steroid and a derivative of 19-nortestosterone. It differs from norethisterone (17α-ethynyl-19-nortestosterone) and etynodiol (17α-ethynyl-3-deketo-3β-hydroxy-19-nortestosterone) only by the lack of a ketone group and hydroxyl group at the C3 position, respectively. Synthesis Chemical syntheses of<unk>  have been published. In another approach to analogues, nortestosterone (1) is first converted to the dithioketal (2) by treatment with dithioglycol in the presence of boron trifluoride. (The mild conditions of this reaction compared to those usually employed in preparing the oxygen ketals probably accounts for the double bond remaining at 4,5). Treatment of this derivative with sodium in liquid ammonia affords the 3-desoxy analog (3). Oxidation by means of Jones reagent followed by ethynylation of the 17-ketone leads to the orally active progestin (6).<unk>  synthesis:
Lynestrenol
Allylestrenol
Ethylestrenol
Norethandrolone
Androstanolone
Norethisterone
Nandrolone
Androstanolone valerate