Greenwayodendron ollveri Verdc. (syn. Polyalthia oliveri EngI., Annonaceae) grows as a small tree up to 13 m high in the rain forests from Sierra Leone to Eastern Nigeria (3). The plant is used in folk medicine (3, 4) and was already the subject of phytochemical investigations (5—8). During our studies on African Annonaceae (9), we isolated from the stem bark of G. oliveri the phenanthrene-type alkaloid uvariopsamine (1) (10), the indolosesquiterpene polyalthenol (6), the triterpene polycarpol (7), and the aporphine alkaloid oliverine (8). In contrast to the three other compounds, uvariopsamine has not been previously known as a constituent of G. oliveri and, up-to-now, it has only been described from the Annonaceae Uvariopsis guineensis (10).