Total synthesis of (+/-)-11 alpha-hydroxyprogesterone by cyclization of a polyunsaturated epoxide.
The total synthesis of a typical 11-hydroxylated steroid, (+/-)-11 alpha-hydroxyprogesterone, was achieved by picric acid-catalyzed tricyclization of a polyunsaturated epoxide appropriately substituted with ketal, hydroxyl, and acetylenic units. This epoxide was prepared by a multistage sequence featuring two successive alkylations of intermediary, monocyclic sulfones. The first sulfone intermediate was obtained by means of a short sequence starting from levulinic acid and diethyl succinate and involving a selective cyclization reaction.
D003500:Cyclization; D004852:Epoxy Compounds; D006908:Hydroxyprogesterones / Q000138:chemical synthesis*
D004852:Epoxy Compounds; D006908:Hydroxyprogesterones; C030228:11-hydroxyprogesterone