申请人:The Dow Chemical Company
公开号:US04447636A1
公开(公告)日:1984-05-08
Improved procedures and intermediates for synthesizing 11-deoxyprostaglandins wherein trans-2,3-dicarbomethoxycyclopentanone is subjected to a novel alcoholysis with .beta.,.beta.,.beta.-trichloroethanol to substitute a .beta.,.beta.,.beta.-trichlorocarboethoxy group at the 2-position followed by alkylation to allow for a wide range of upper side chains to be introduced at the 2-position of the cyclopentanone ring. The unwanted .beta.,.beta.,.beta.-trichlorocarboethoxy group at the 2-position can then be removed easily by a zinc induced elimination-decarboxylation sequence. Base catalyzed epimerization of the 2-position side chain to the desired trans-configuration, relative to the carbomethoxy group in the 3-position, is followed by partial reduction of the 2-hexynyl moiety of the side chain to the desired cis-olefinic group of the E.sub.2 -type 11-deoxyprostaglandins, or through total reduction to the alkane upper side chain of E.sub.1 -type prostaglandin analogs. Modification thereafter of the carbonyl group at the 3-position of the cyclopentanone ring by a variety of reagents allows introduction of the lower side chain present in the prostaglandins themselves or a variety of other side chains derived from the 3-carboxy-, 3-hydroxymethyl- or 3-aldehyde-substituted cyclopentanone ring. From the latter, 11-deoxyprostaglandins can be prepared by known procedures.
改进的程序和中间体用于合成11-去氧前列腺素,其中将trans-2,3-二羧甲氧基环戊酮经过一种新颖的醇解反应,用β,β,β-三氯乙醇取代2位置的β,β,β-三氯羧乙氧基团,然后进行烷基化,以便在环戊酮环的2位置引入各种上侧链。然后,不需要的2位置的β,β,β-三氯羧乙氧基团可以通过锌诱导的消除-脱羧序列轻松去除。通过碱催化的2位置侧链的对映异构化,使其转变为所需的相对于3位置的羧甲氧基团的反式构型,然后对侧链的2-己炔基部分还原为所需的E.sub.2型11-去氧前列腺素的顺式烯基基团,或者通过完全还原为E.sub.1型前列腺素类似物的烷基上侧链。然后通过各种试剂对环戊酮环的3位置的羰基团进行修饰,可以引入前列腺素本身中存在的下侧链或来自3-羧基、3-羟甲基或3-醛基取代环戊酮环的各种其他侧链。从后者中,11-去氧前列腺素可以通过已知的程序制备。