Resolution of an Iridoid Synthon, Gastrolactol, by Means of Dynamic Acetylation and Lipase-Catalyzed Alcoholysis
作者:Ellen M. Santangelo、Didier Rotticci、Ilme Liblikas、Torbjörn Norin、C. Rikard Unelius
DOI:10.1021/jo015592y
日期:2001.8.1
A short synthetic route to asymmetric iridoids was developed. The three key steps were an intramolecular [4 + 2] cycloaddition reaction of an enamine derivative of 8-oxocitral (2), a dynamic acetylation, and an enzymatic resolution of the gastrolactyl acetates 5a and 5b, iridoids with three stereocenters. Some regio- and stereoselective heterogeneous catalytic hydrogenations of double bonds in iridoid
iridoids including jatamanin A, F, G and J, gastrolactone and nepetalactone have been synthesized via the efficient transformation of a core cyclopenta[c]pyran intermediate. Key features of the syntheses include the stereoselective construction of the core cyclopenta[c]pyran skeleton of the iridoid lactones via a Pd(0)-catalyzed intramolecular allylic alkylation, and the facile transformation of the common
通过核心环戊五[ c ]吡喃中间体的有效转化,合成了六种天然鸢尾酮,包括其茄木素A,F,G和J,胃内酯和荆芥内酯。合成的关键特征包括通过Pd(0)催化的分子内烯丙基烷基化反应,使烯丙基内酯的核心环戊环[ c ]吡喃骨架立体选择性构建,以及将常见中间体轻松转化为天然烯酮的能力。