The stem and stem bark of Artabotrys uncinatus afforded two cytotoxic aporphine alkaloids, liriodenine and atherospermidine, as well as a novel 11 -oxoaporphine, artacinatine, which is inactive. The structure of artacinatine was elucidated from spectral data in conjunction with a single-crystal X-ray analysis. © 1989.