The West-African plant Polyalthia oliveri has yielded a new triterpene polycarpol, an indolosesquiterpene of a new structural type polyalthenol, and eleven aporphine alkaloids, six of which are novel. The major alkaloids from leaves and stem-barks are 7-hydroxy- and 7-methoxyaporphines, oliveridine, oliveroline, oliverine; there are also two alkaloids which are N-oxy-7-substituted aporphines. NMR characteristics and the phytochemical significance of these alkaloids are discussed.