Chemistry Lynestrenol
lynestrenol, known 17α-ethynyl-3-desoxy-19-nortestosterone or 17α-ethynylestr-4-en-17β-ol, synthetic estrane steroid , derivative of 19-nortestosterone. differs norethisterone (17α-ethynyl-19-nortestosterone) , etynodiol (17α-ethynyl-3-deketo-3β-hydroxy-19-nortestosterone) lack of ketone group , hydroxyl group @ c3 position, respectively. synthesis in approach analogs, nortestosterone (1) first converted dithioketal (2) treatment dithioglycol in presence of boron trifluoride. (the mild conditions of reaction compared employed in preparing oxygen ketals accounts double bond remaining @ 4,5). treatment of derivative sodium in liquid ammonia affords 3-desoxy analog (3). oxidation means of jones reagent followed ethynylation of 17-ketone leads orally active progestin (6). lynestrenol synthesis: