5-[(Aminoalkyl)amino]imidazo[4,5,1-de]acridin-6-ones as a novel class of antineoplastic agents. Synthesis and biological activity.

A new class of antineoplastic agents, the 5-substituted imidazo[4,5,1-de]acridin-6-ones with an (aminoalkyl)amino group in the side chain, has been made. These compounds were synthesized by reduction of 1-substituted 4-nitroacridin-9(10H)-ones and subsequent reaction of the derived amines with carboxylic acids. Their cytotoxic activity against HeLaS3 cells in tissue culture and in vivo antitumor activity against P388 leukemia in mice was demonstrated. A strict relationship between the antineoplastic activity and the number of methylene spacers between proximal and distal nitrogens in the side chain was established.