Synthesis of dl-Mesembrine and Its trans Isomer

Abstract

dl-Mesembrine (=3a-(3, 4-dimethoxyphenyl)-1-methyloctahydroindol-6-one) (XIII) and its trans isomer (XIV) were prepared from 3a-(3, 4-dimethoxyphenyl)-1-methyloctahydroindol-2, 6-dione (IV) in 4 steps. Stereochemistry of 3a-(3, 4-dimethoxyphenyl)-1-methyloctahydroindol-2, 6-dione was discussed on the basis of nuclear magnetic resonance (NMR) informations.