In an investigation of a new class of deoxyribonucleic acid (DNA)-intercalating antitumor agents, novel acridinyl-substituted uracils have been synthesized and evaluated for activity against L1210 leukemia in vivo, and against bacteria and fungus. These compounds were prepared by the novel enamine reaction between 9-chloroacridines and 6-aminouracils. The positional effects of substituents on the acridine ring showed that compounds bearing electron-withdrawing groups at the 3- or 6-position of the acridine ring were the most active.