A series of N-, S-, and O-mononitro- and dinitrobenzyl derivatives of heterocycles was synthesized by alkylation of heterocyclic bases with the respective nitrobenzyl chlorides. Of the newly synthesized compounds, dinitrobenzylsulfanyl derivatives of 1-methyl-2-mercaptoimidazole (2c) and of 5-nitro- and 5,6-dichloro-2-mercaptobenzimidazole (8b and 8c, and 8e and 8f, respectively) showed considerable antimycobacterial activity. On a molar basis, nine of the novel compounds showed also a considerably higher antiprotozoal efficacy than metronidazole that reduced T. hominis viability to 73.5% at 8 μg/ml.