COSTARICINE, A NEW ANTIPLASMODIAL BISBENZYLISOQUINOLINE ALKALOID FROMNECTANDRA-SALICIFOLIA TRUNK BARK

A MeOH extract of Nectandra salicifolia trunk bark, obtained during a diversity-based plant collection in a lower montane rainforest in Cost a Rica, showed activity in an in vitro antiplasmodial assay measuring incorporation of [H-3]-labeled hypoxanthine by Plasmodium falciparum. In addition to 15 known alkaloids isolated from samples of trunk bark, roots, and leaves/twigs of this species, a new bisbenzylisoquinoline alkaloid (+)-costaricine [(+)-12-O-methyllindoldhamine] (1) was isolat ed from bark (0.038% yield) and from roots (0.001%). (+)-Costaricine w as active in the antiplasmodial assay, with IC50 values of 50 ng/mL vs . the chloroquine-sensitive D6 clone and 294 ng/mL vs. the chloroquine -resistant W2 clone of P. falciparum.