Synthesis, DNA Binding, and Leishmania Topoisomerase Inhibition Activities of a Novel Series of Anthra[1,2-d]imidazole-6,11-dione Derivatives

Nine novel anthra[1,2-d]imidazole-6,11-diones, differing in their side chain, were synthesized. UV−vis spectroscopy and viscometric titrations of these molecules with duplex DNA were used to assess their binding with DNA. Five of the nine compounds showed high inhibition activity against topoisomerase I of Leishmania donovani, with the one bearing the tetrazole side chain exhibiting an IC50 ∼ 1 μM. The inhibition activities were not related with their DNA binding affinity and depended on the nature of the side chain.