通过二甲基二氧杂环丙烷对3α,6-和3α,24-二羟基-5β-胆烷衍生物中未活化碳的官能化反应

Functionalization of unactivated carbons in 3alpha,6- and 3alpha,24-dihydroxy-5beta-cholane derivatives by dimethyldioxirane.

作者信息

Iida Takashi, Shiraishi Keisuke, Ogawa Shoujiro, Goto Takaaki, Mano Nariyasu, Goto Junichi, Nambara Toshio

机构信息

Department of Chemistry, College of Humanities & Sciences, Nihon University, Setagaya, Sakura-jousui, Tokyo 329-1151, Japan,

出版信息

Lipids. 2003 Mar;38(3):281-7. doi: 10.1007/s11745-003-1062-4.

DOI:10.1007/s11745-003-1062-4

PMID:12784869

Abstract

Direct remote functionalization of unactivated carbons by dimethyldioxirane (DMDO) was examined for 3alpha,6- and 3alpha,24-dihydroxy-5beta-cholane derivatives. DMDO oxidation of stereoisomeric methyl 3alpha,6-diacetoxy-5beta-cholanoates caused the direct, unexpected 14alpha- and 17alpha-hydroxylations, in analogy with that of the 5alpha-H analogs, regardless of the differences in stereochemical configuration of the A/B-ring junction and of the acetoxyl groups at C-3 and C-6. On the other hand, the ester derivatives of 3alpha,24-dihydroxy-5beta-cholane with DMDO were transformed into the corresponding 5beta-, 14alpha-, and 17alpha-hydroxy compounds, whereas the ether derivatives yielded the 5beta-hydroxy, 3-oxo, and C-24 oxidized products, accompanied by their dehydrated ones.

摘要

研究了用二甲基二氧杂环丙烷（DMDO）对未活化碳进行直接远程官能团化反应，以用于3α,6 - 和3α,24 - 二羟基 - 5β - 胆烷衍生物。立体异构的3α,6 - 二乙酰氧基 - 5β - 胆酸甲酯的DMDO氧化反应导致了直接且意外的14α - 和17α - 羟基化反应，这与5α - H类似物的情况类似，而与A/B环连接以及C - 3和C - 6处乙酰氧基的立体化学构型差异无关。另一方面，3α,24 - 二羟基 - 5β - 胆烷的酯衍生物与DMDO反应转化为相应的5β - 、14α - 和17α - 羟基化合物，而醚衍生物则生成5β - 羟基、3 - 氧代和C - 24氧化产物，并伴有脱水产物。