Synthesis and antitumor activity of 1-substituted-2-methyl-5-nitrobenzimidazoles

Different substituents were introduced in position 1 of 2-methyl-5(6)-nitro-1H-benzimidazole (2) in order to obtain different side chains having different heterocyclic compounds, for example, thiadiazoles (5-7), tetrazoles (8, 9a, b), triazoles (11-13), thiazoles (14a-e), triazines (10, 16, 17), and imidazoles (18a-c). The antitumor effect of compounds 1, 2, 2a, 4, 5, 7, 8, 9a, 10, 13, 14a, 15, 16, and 18c was studied against breast cancer (MCF7) and compounds 2 [IC50 = 4.52 mu g] and 7 [IC50 = 8.29 mu g] were found to be active. (c) 2006 Elsevier Ltd. All rights reserved.