Bioassay-guided fractionation of the leaf extracts of Buchenavia capitata via partition chromatography on silica and high-speed countercurrent chromatography has led to the isolation of several piperidine-flavonoid alkaloids with anti-HIV activity. The lead compound, 0-demethyl buchenavianine, shows activity at 100 ng/ml, while other homologs isolated thus far are less active. The compounds are being thoroughly characterized by 1H and 13C-NMR (including HMBC and HMQC) and high resolution mass spectrometry.
