Synthesis and antiproliferative activity of some benzimidazole-4,7-dione derivatives.

A series of benzimidazole-4,7-diones bearing at the 2-position the thiomethyl group or the 2-pyridyl moiety has been synthesized and tested in vitro on three tumor cell lines. Two of them show a very good antiproliferative effect. Compounds 1 and 2d are more active or equiactive, respectively, than MMC against human lymphoblastic leukemia. Both compounds exhibit high activity on human non-Hodgkin lymphoma. Compound 1 is non toxic at all the concentrations used in the antiproliferative assay and 2d is toxic only at high concentration.