Structure-activity relationship studies on 2,5,6-trisubstituted benzimidazoles targeting Mtb-FtsZ as antitubercular agents

Experimental and theoretical studies on antituberculosis activity of different benzimidazole derivatives

Tuberculosis (TB) continues to be one of the deadliest infectious diseases with a rapid increase in multidrug-resistant cases. The discovery of new agents against tuberculosis is urgently needed. Thus, the research article focuses on the antituberculosis activity of a series of benzimidazolium compounds. The antituberculosis activities of compounds including benzimidazole core (7a-h) against Mycobacterium tuberculosis H37Rv strain were tested in vitro using the BACTEC MGIT 960 system. The concentrations of benzimidazole compounds were adjusted to range from 0.25 to 4 μg/ml. The antituberculosis interactions of the compounds were investigated by molecular docking and molecular dynamics simulation. The results revealed that only benzimidazolium salt 7h showed antituberculosis activity at MIC value of 2 μg/ml although the other compounds showed no antituberculosis activity. The docking data revealed that 7h could bind to InhA thus indicating its inhibition potential on the enzyme. Molecular dynamics simulation exhibited that 7h formed a stable complex with the enzyme and was able to remain inside the binding region of the enzyme. Besides, the pharmacokinetic and drug-likeness properties of the compounds were assessed through computational approaches. The compounds exhibited drug-like properties. Consequently, 7h could be a good candidate for the development of new TB drugs.

Synthetic approaches to potent heterocyclic inhibitors of tuberculosis: A decade review

Tuberculosis (TB) continues to be a significant global health concern with about 1.5 million deaths annually. Despite efforts to develop more efficient vaccines, reliable diagnostics, and chemotherapeutics, tuberculosis has become a concern to world health due to HIV, the rapid growth of bacteria that are resistant to treatment, and the recently introduced COVID-19 pandemic. As is well known, advances in synthetic organic chemistry have historically enabled the production of important life-saving medications that have had a tremendous impact on patients' lives and health all over the world. Small-molecule research as a novel chemical entity for a specific disease target offers in-depth knowledge and potential therapeutic targets. In this viewpoint, we concentrated on the synthesis of a number of heterocycles reported in the previous decade and the screening of their inhibitory action against diverse strains of Mycobacterium tuberculosis. These findings offer specific details on the structure-based activity of several heterocyclic scaffolds backed by their in vitro tests as a promising class of antitubercular medicines, which will be further useful to build effective treatments to prevent this terrible illness.

Bacterial FtsZ inhibition by benzo[d]imidazole-2-carboxamide derivative with anti-TB activity

Aims: The present study aimed to assess the mode of action of previously reported anti- Mycobacterium tuberculosis benzo[ d]imidazole-2-carboxamides against FtsZ along with their antibacterial potential. Materials & methods: The anti-mycobacterial action of benzo[ d]imidazole-2-carboxamides against FtsZ was evaluated using inhibition of Bacillus subtilis 168, light scattering assay, circular dichroism spectroscopy, in silico molecular docking and molecular dynamics simulations. Results & conclusion: Three compounds (1k, 1o and 1e) were active against isoniazid-resistant strains. Four compounds (1h, 1i, 1o and 4h) showed >70% inhibition against B. subtilis 168. Compound 1o was the most potent inhibitor (91 ± 5% inhibition) of  B. subtilis 168 FtsZ and perturbed its secondary structure. Molecular docking and molecular dynamics simulation of complexed 1o suggested M. tuberculosis FtsZ as a possible target for antitubercular activity.