甾体 16α,17α,22-三醇的非常规氧化转化。

Unusual oxidative transformations of a steroidal 16alpha,17alpha,22-triol.

机构信息

Institute of Chemistry, University of Białystok, al. Piłsudskiego 11/4, 15-443 Białystok, Poland.

出版信息

Steroids. 2010 Jan;75(1):70-6. doi: 10.1016/j.steroids.2009.10.002. Epub 2009 Oct 24.

DOI:10.1016/j.steroids.2009.10.002

PMID:19857506

Abstract

A number of unexpected reactions were observed during attempts to invert configuration at C16 in 16alpha,17alpha,22-triol 3a. The PDC oxidation of 3a produced the D-seco-aldehyde 4a. Analogous compound 4b was obtained by Swern oxidation of the 16alpha,17alpha-dihydroxy-22-O-TES-ether 3b in addition to the desired 16-ketone 7. The unprotected triol 3a yielded pentacyclic products 5 and 6 under similar conditions. The Mitsunobu reaction of the triol 3a afforded 16-ketone 8 with inverted configuration of the side chain. During heating of a solution of 3a in THF with NaH at reflux autoxidation to the 16-ketone cyclic hemiketal 5, identical to one of the Swern oxidation products, took place.

摘要

在尝试将 16α,17α,22-三醇 3a 中 C16 的构型翻转时，观察到了一些意外的反应。PDC 氧化 3a 生成了 D-去甲醛 4a。通过 Swern 氧化 16α,17α-二羟基-22-O-TES-醚 3b，除了得到所需的 16-酮 7 外，还得到了类似的化合物 4b。在类似的条件下，未保护的三醇 3a 生成了五环产物 5 和 6。三醇 3a 的 Mitsunobu 反应得到了侧链构型翻转的 16-酮 8。在 THF 中回流加热 3a 的溶液与 NaH 时，发生了自氧化反应，生成了与 Swern 氧化产物之一相同的 16-酮环半缩酮 5。