19-Hydroxy-5β, 19-cyclosteroids: synthesis, isomerization and ring opening

JF Templeton

Index: Templeton, John F.; Ling, Yangzhi; Lin, Weiyang; Majgier-Baranowska, Helena; Marat, Kirk Journal of the Chemical Society - Perkin Transactions 1, 1997 , # 12 p. 1895 - 1904

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Citation Number: 2

Abstract

19 (R/S)-Hydroxy-5β, 19-cyclosteroids have been synthesised from the 19-formyl 4-en-3- one by reductive cyclization with zinc in aqueous acetic acid. Treatment of the aldehyde with lithium in liquid ammonia also gave the 19 (R)-hydroxy-5β, 19-cyclosteroid together with the 17β-hydroxy analogue. The 19 (R)-alcohol is isomerized to the 19 (S)-alcohol in either dilute acidic or basic media via the 3-hydroxy-3, 5-cyclosteroid. The 19 (S)-alcohol is in ...