A New and Convenient Synthesis of 1α,25-Dihydroxyvitamin D<sub>2</sub>and Its 24<i>R</i>-Epimer
作者:Masahiro Tsuji、Shinji Yokoyama、Yoji Tachibana
DOI:10.1246/bcsj.62.3132
日期:1989.10
4-triazolidine-1,2-diyl)-23,24-dinor-6-cholene-1α,3β-diyl diacetate (12) starting from (22E)-5,7,22-ergostatriene-1α,3β-diyl diacetate (10), a precursor of 1α-hydroxyvitamin D2. Introduction of the new side chain with the desired stereochemistry was carried out selectively by the reductive elimination of the β-hydroxy sulfone derived from the C-22 aldehyde (12) and an optically active sulfone, prepared
1α, 25-二羟基维生素 D2 (1a) 是通过辐射和随后的 (22E)-5,7,22-麦角三烯-1α,3β,25-三醇 (16a) 的热异构化合成的。三醇16a通过22-oxo-5α,8α-(4-phenyl-3,5-dioxo-1,2,4-triazolidine-1,2-diyl)-23,24-dinor-6-cholene- 1α,3β-二乙酸二酯 (12) 从 (22E)-5,7,22-ergostattriene-1α,3β-二乙酸二酯 (10) 开始,1α-羟基维生素 D2 的前体。通过还原消除衍生自 C-22 醛 (12) 的 β-羟基砜和通过 (S)-2,3- 制备的光学活性砜,选择性地引入具有所需立体化学的新侧链来自 (S)-3-羟基-2-甲基丙酸甲酯的二甲基-1,3-丁二醇。类似地合成了1a的C-24差向异构体。