The Woodward (Grignard) synthesis of cholestanol has been extended to the preparation of cholesterol and related stenols by employing a Δ5-3β-ol precursor, masking the 5,6-double bond of the Grignard product by epoxidation, eliminating the hydroxyl group at C-20 via the olefin, and regenerating the Δ5-Sβ-ol system. This method has been used to prepare 11-ketocholesterol for the first time and, from
伍德沃德(格利雅)
胆甾烷醇的合成一直延伸
胆固醇的制备和通过采用相关Δstenols 5 -3β醇前体,掩蔽由环氧化格利雅产品的5,6-双键,消除在羟基C-20通过烯烃,并再生Δ 5 -Sβ醇系统。该方法首次用于制备11-酮
胆固醇,并由此制备11-羟基
胆固醇,11-酮和11β-羟基
胆固醇烯酮和一些相关化合物。