The major alkaloid of Dracontomelum mangiferum Bl. (family Anacardiaceae) has been identified as (-)-1, 2, 3, 4, 6, 7-hexahydro-12H- indolo[2, 3-α]quinolizine, which has not been found previously in nature although the (±) form has been synthesized. © 1966 CSIRO. All rights reserved.