Enantiospecific Total Synthesis of (−)-Anhydromacrosalhine-methine and Partial Synthesis of the Antiamoebic Bisindole Alkaloid (−)-Macrocarpamine<sup>1</sup>
作者:Tong Gan、James M. Cook
DOI:10.1021/jo971570t
日期:1998.3.1
An enantiospecific total synthesis of (-)-anhydromacrosalhine-methine (7a) was completed from D-(+)-tryptophan via the asymmetric Pictet-Spengler reaction. In addition, a partial synthesis of (-)-anhydromacrosalhine-methine (7a) was carried out from the natural product (+)-ajmaline (10). The coupling reaction of plant-derived (+)-pleiocarpamine (8) with synthetic diene 7a provided the antiamoebic bisindole alkaloid (-)-macrocarpamine (1) in 75% yield. This sequence serves as the first example of the action of a nucleophile at [at C(2)] on a protonated form [C(3)] of pleiocarpamine 8 in the Alstonia series to provide a bisindole alkaloid.