Appropriately substituted benzo [i] phenanthridines structurally related to nitidine, a benzo [c] phenanthridine alkaloid with antitumor activity, are active as topoisomerase I-targeting agents. Studies on benzo [i] phenanthridines have indicated analogues that possess a 2, 3- methylenedioxy moiety and at least one and preferably two methoxyl groups at the 8-and 9- positions, such as 8, 9-dimethoxy-2, 3-methylenedioxybenzo [i] phenanthridine, 2, are ...
