Corydalis属植物の成分研究(第8報)Dehydrocorydaline関連化合物の合成

抄録

In order to examine the anti-gastric ulcer activity of dehydrocorydaline derivatives, 13-substituted berberine (4a-g) and the partial O-demethylated derivatives of dehydrocorydaline were synthesized. Demethylation of dehydrocorydaline by refluxing with concentrated hydrochloric acid gave a mixture of 2-monophenol (7a), 9-monophenol (7b), and 2, 9-diphenol (7c). The structures of these phenols were deduced from the nuclear magnetic resonance and mass spectra of their tetrahydroderivatives (8a-c). It was found that the chemical shifts of aromatic protons were informative for assinging the position of the phenolic group in 2, 3, 9, 10-substituted tetrahydroprotoberberine alkaloids.