Design and synthesis of novel benzimidazole derivatives as anti-tuberculosis agents.

In recent studies some urea derivatives have been identified as potent anti-tuberculosis agents by targeting mycobacterial membrane protein large 3 (MmpL3). However, this compound series as exemplified by AU1235 exhibited poor in vitro pharmacokinetic profile. With AU1235 as the lead, we have identified a novel benzimidazole series as potential anti-tuberculosis agents by using scaffold hopping approach. Among these synthesized compounds, 2-aminobenzimidazole derivative 8b showed the potent anti-tuberculosis activity with the MIC value of 0.03 microg x mL(-1). This compound also showed improved metabolic stability compared to AU1235. Our investigation indicated that benzimidazole derivatives are the promising lead for further optimization as anti-tuberculosis agents.