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
Total Synthesis of the Opioid Agonistic Indole Alkaloid Mitragynine and the First Total Syntheses of 9-Methoxygeissoschizol and 9-Methoxy-<i>N</i><sub>b</sub>-methylgeissoschizol
作者:Jun Ma、Wenyuan Yin、Hao Zhou、James M. Cook
DOI:10.1021/ol071220l
日期:2007.8.1
An enantiospecific method for the synthesis of 4-methoxytryptophan has been developed via a regiospecific Larock heteroannulation and employed for the firsttotalsyntheses of 9-methoxygeissoschizol and 9-methoxy-Nb-methylgeissoschizol, as well as the totalsynthesis of the opioid agonistic alkaloid mitragynine. The asymmetric Pictet-Spengler reaction and a Ni(COD)2-mediated cyclization served as key
Two new quaternary alkaloids, 9-methoxy-Nb-methylgeissoschizol and guiachrysine together with the known compounds C-alkaloid O, fluorocurine, mavacurine, macusine B and C-profluorocurine, were isolated from Strychnos guianensis stembark. The structures of the compounds were elucidated on the basis of spectroscopic studies.
两种新的季生物碱 9-甲氧基-Nb-甲基geissoschizol 和 guiachrysine 以及已知的化合物 C-生物碱 O、fluorocurine、mavacurine、macusine B 和 C-profluorocurine,从马钱子树的茎皮中分离出来。在光谱研究的基础上阐明了化合物的结构。