Isoschizogamine was isolated from the twigs of Schizozygia caffaeoides and its structure revised to 10 on the basis of NMR analysis. It is shown to possess as yet undescribed hexacyclic skeleton of N-acyl 1,2,3,4-tetrahydroquinoline type, the nitrogen atom of which is included in an animal moiety.The alkaloid is proposed to originate from schizozygane-type intermediates through oxidation, aziridine formation and subsequent ring opening.