Psychotria forsteriana

Roth, A., Kuballa, B., Bounthanh, C., Cabalion, P., Sevenet, T., Beck, J. P. and Anton, R. 1986. Cytotoxic activity of polyindole alkaloids of Psychotria forsteriana (Rubiaceae). Plant Medica, 450 53. 

Three calycanthine-type alkaloids, (—)-calycanthine (149) (the optical antipode of (+ )-calycanthine (150)), (—)-isocalycanthine (151), and we,so-chimonanthine (152) were isolated from Psychotria forsteriana, from New Caledonia, and complete and NMR assignments were reported (101). This represents the second isolation of the levorotatory isomer of calycanthine (the first was from Pausinystalia macroceras, Rubiaceae, (102)) as well as the first isolation of we,so-chimonanthine. (—)-Calycanthine and (+ )-chimonanthine (153) were also found to occur in the skin of the Colombian poison dart frog, Phyllobates terribilis (103). 

Beretz A, Roth-Georger A, Corre G, Kuballa B, Anton R, Cazenave J (1985) Polyindolinic alkaloids from Psychotria forsteriana. Potent inhibitors of the aggregation of human platelets. Planta Med 51 300-303. doi 10.1055/s-2007-969496... 

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