Shing T K, Jiang Q
Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong.
J Org Chem. 2000 Oct 20;65(21):7059-69. doi: 10.1021/jo000877g.
A total synthesis of (+)-quassin from naturally occurring (S)-(+)-carvone is described. The total number of steps was 28, and the overall yield was about 2.6%. The synthetic strategy for the construction of the tetracyclic carbon framework was based on a C-->ABC-->ABCD ring annulation sequence, involving an aldol reaction, an intramolecular Diels-Alder reaction, and an intramolecular acylation as the key steps. Subsequent functionalization of ring A and ring C then afforded the target (+)-quassin.
本文描述了以天然存在的(S)-(+)-香芹酮为原料全合成(+)-苦木素的过程。总步数为28步，总产率约为2.6%。构建四环碳骨架的合成策略基于C→ABC→ABCD的环化序列，其中关键步骤包括羟醛反应、分子内狄尔斯-阿尔德反应和分子内酰化反应。随后对A环和C环进行官能团化反应，得到目标产物(+)-苦木素。
