Alkaloide aus Conopharyngia durissima STAPF Isovoacangin, Conopharyngin, Conodurin und Conoduramin

Abstract

One known and four new alkaloids have been isolated from C. durissima STAPF. Isovoacangine (VII) (first isolated from Stemmadenia), conopharyngine (VIII), and possibly also Alkaloid E are monomeric isoquinuclidine bases found in root and stem bark; conodurine and conoduramine, however, are dimeric and found only in the roots. A mild and simple method is described for the decarbomethoxylation of ester bases of the voacangine type to substances of the ibogaine type.