3-Methoxysampangine, a novel antifungal copyrine alkaloid from Cleistopholis patens.

Further examination of the active ethanolic extract of the root bark of Cleistopholis patens by using bioassay-directed fractionation resulted in the isolation of a new alkaloid, 3-methoxysampangine (compound I), together with three known alkaloids, eupolauridine (compound II), liriodenine (compound III), and eupolauridine N-oxide (compound IV). The proposed structure of compound I was based on its physicochemical properties and spectral data. 3-Methoxysampangine exhibited significant antifungal activity against Candida albicans, Aspergillus fumigatus, and Cryptococcus neoformans. This is the first report of the isolation of liriodenine (compound III) from the root bark of C. patens.