Ichimoto I, Machiya K, Kirihata M, Ueda H
Department of Agricultural Chemistry, College of Agriculture, University of Osaka Prefecture, Japan.
Agric Biol Chem. 1990 Mar;54(3):657-62.
A convenient synthetic method for the marine antibiotic (-)-malyngolide and its stereoisomers was accomplished from a chiral alpha-alkoxyketone (4), which was readily available as a chiron. Chiral quaternary carbon synthons (5a) and (5b) as the key intermediates were constructed by the chelation controlled addition of Grignard reagent to 4. The diastereomeric mixture of 5a and 5b was readily transformed into a separable mixture of lactones (7a) and (7b), each of which could be easily separated by silica-gel column chromatography. (-)-Malyngolide and its three stereoisomers were obtained in optically pure form without the need for optical resolution.
一种用于合成海洋抗生素（-）-马琳戈内酯及其立体异构体的简便方法是由手性α-烷氧基酮（4）完成的，该手性α-烷氧基酮作为一种手性源很容易获得。通过格氏试剂对4的螯合控制加成构建了作为关键中间体的手性季碳合成子（5a）和（5b）。5a和5b的非对映体混合物很容易转化为内酯（7a）和（7b）的可分离混合物，每种内酯都可以通过硅胶柱色谱轻松分离。无需进行光学拆分即可获得光学纯形式的（-）-马琳戈内酯及其三种立体异构体。
