Camptothecin-related alkaloids from hairy roots of Ophiorrhiza pumila

Hairy roots of Ophiorrhiza pumila, a rubiaceous camptothecin-producing plant, were obtained. From an investigation of the secondary metabolites, it was found that the hairy roots produced camptothecin and its related alkaloids, i.e. (3S)-pumiloside, (3S)- and (3R)-deoxypumilosides and strictosamide. We also isolated two new camptothecinoids, OPHR-23 and OPHR-17, the structures of which including the absolute configurations, were determined by spectroscopic analyses and chemical conversion from tryptamine and secologanin.