Michellamines A and B, naphthylisoquinoline dimeric alkaloids from the leaf of a previously undescribed species of the genus Ancistrocladus, show and-human immunodeficiency virus (HIV) activity in an in vitro screen. In order to determine the distribution of these alkaloids in the genus, the level of production in the new species, and to gain an understanding of the horticultural aspects of production, a sensitive high pressure liquid chromatography analytical method requiring a small biomass was developed. This method resolved michellamines A and B and congeners and enabled quantitation of each. The production of the michellamines was found to be limited to the new species, A. korupensis.