Aminonaphthacene derivatives of the formula:
wherein R 1 is a hydrogen atom, a hydroxyl group or a lower alkoxy group, R 2 is a hydrogen atom or a hydroxyl group, R 3 and R 4 are each a lower alkyl group or, when taken together, represent an ethylenedioxy group or an oxo group and R 6 and R 8 are each a hydrogen atom, a lower alkyl group or a group of the formula: -A-Q (in which A is an alkylene group optionally bearing at least one lower alkyl and Q is a hydrogen atom, a hydroxyl group, a lower alkoxy group or a group of the formula:
wherein R 7 and R 8 are each a hydrogen atom, a lower alkyl group, a benzyl group, a hydroxy (lower) alkyl group or an amino (lower) alkyl group or, when taken together with the adjacent nitrogen atom to which they are attached, represent a 5 to 7-membered nitrogen-containing ring optionally having an additional nitrogen or oxygen atom in the ring and optionally bearing any substituent on the ring) or, R 5 and R 6 when taken together with the adjacent nitrogen atom to which they are attached, represent a 5 to 7-membered nitrogen-containing ring optionally having an additional nitrogen or oxygen atom in the ring and optionally bearing any substituent on the ring, and their acid addition salts, which are useful as anti-tumor agents.