The quinone-imine derivative obtained by biochemical oxidation of 2, N2-methyl-9-hydroxyellipticinium acetate, is found to react regiospetifically at C-10 with N, 0 ans S nucleophiles. It has been reported' that some ellipticine derivatives manifest a much greater antitumour activity than ellipticine itself, 1 (5, il-aimethyl-6H-pyrido14,3bl carbazole). One of these derivatives, 2, N2-methyl-9-hydroxyellipticinium, (9-OH-NME+),which is obtained from t by hydroxylation at"OC-9 and methylation of the pyridine nitrogen,shows avery interesting activity and is currently under clinical investigation2. ; ELLIPTICINE 3 Q-0X0-NME+ o~~~~ CH3 o&@@yL_2 Q,lO-diOXO-NME+ w3 The respective positions of the hydroxyl and the indolic (N-H) groups, which are para to each other, actually suggest that the drug ,?, might be activated in uivo through oxidative pathways. Our recent work3 on the formation of two quinone derivatives, 3 and t, via peroxidase oxidation of $ by horseradish peroxidase (HRP) in presence of hydrzgen peroxide, supports indeed this assumption. Bearing in mind the alkylation of biological macromolecules by electrophilic quinoneimine derivatives and the imolied consequences on biological activities 4a , we wish to report here om results about the addition of various nucleophiles (e.g. pyridine and cysteine deriuatives)to 3,which OCCURS regiospecifically at C-10 ; we also want to report the formation of '/u, the quinone-imine obtained C-10 during the oxidatio; of 2 by molecular oxygen in % by addition of a methoxy group at presence of Cu' compounds. In both