Two novel cytotoxic acetogenins, purpurediolin (1) and purpurenin (2), were isolated from the seeds of Annona purpurea. Their structures were elucidated by a combination of chemical and spectral methods including MS and NMR measurements. In addition, six known acetogenins were obtained, namely, bullatacin, squamocin (annonin I), motrilin (squamocin C), annoglaucin, xylomatenin, and annonacin A. Compounds 1 and 2 exhibited potent cytotoxic activity in vitro against six human solid tumor cell lines.