General Approach to the Total Synthesis of 9-Methoxy-Substituted Indole Alkaloids: Synthesis of Mitragynine, as well as 9-Methoxygeissoschizol and 9-Methoxy-<i>N</i><sub>b</sub>-methylgeissoschizol
作者:Jun Ma、Wenyuan Yin、Hao Zhou、Xuebin Liao、James M. Cook
DOI:10.1021/jo801839t
日期:2009.1.2
Herein, the full details of the synthesis of the 9-methoxy-substituted Corynanthe indole alkaloids mitragynine (1), 9-methoxygeissoschizol (3), and 9-methoxy-Nb-methylgeissoschizol (4) are described. Initially, an efficient synthetic route to the optically active 4-methoxytryptophan ethyl ester 20 on a multigram scale was developed via a Mori−Ban−Hegedus indolesynthesis. The ethyl ester of d-4-methoxytryptophan