申请人:The Board of Trustees of Leland Stanford Junior University
公开号:US04064185A1
公开(公告)日:1977-12-20
Compositions are provided as well as methods for preparing the compositions which serve as cyclization precursors for the preparation of C-11 alkenyl substituted steroids and nor-steroids. The alkenyl group may be converted after cyclization to a variety of heterosubstituents to provide heterofunctionalized C-11 steroids and nor-steroids. The compounds are provided having an initiator group, which has a chalcoxy atom in juxtaposition to a double bond, an olefinically unsaturated linking group and a terminating group which acts to from a carbocation which reacts with a nucleophile to provide a stable product. The C-11 substituent is found to provide upon cyclization the alpha-configuration, so that the subject compounds provide a direct route to the difficultly accessible alpha-C-11 substituted steroids, or, if desired, the alpha-configuration can be inverted to the beta-configuration.
本发明提供了一种组合物,以及制备该组合物的方法,该组合物作为环化前体物用于制备C-11烯基取代类固醇和去甲类固醇。烯基基团可以在环化后转化为各种杂原子取代基,从而提供杂原子功能化的C-11类固醇和去甲类固醇。所提供的化合物具有起始基团,该起始基团在双键旁具有硫代氧基原子,具有烯丙基不饱和连接基团和终止基团,该终止基团作用是形成一个带正电荷的碳离子,该离子与亲核试剂反应形成稳定产物。发现C-11取代基在环化后提供α构型,因此这些化合物提供了一种直接途径制备难以获得的α-C-11取代类固醇,或者如果需要,α构型可以被反转为β构型。