Synthesis of benzimidazole derivatives bearing amide bridgeand investigation of their anti-tuberculosis activities

Aim: Tuberculosis is considered one of the major diseases severely impacting public health today. It is notably the most prevalent disease caused by infectious agents with high mortality rates. While effective drugs for its treatment exist, the emergence of drug-resistant strains poses significant challenges. Therefore, the importance of developing new and effective drug molecules has increased. Material and Method: Six benzazole derivative compounds designed based on literature information indicating that compounds carrying benzimidazole and isoster structures have antimycobacterial effects were synthesized using polyphosphoric acid (PPA) and condensation methods in a two-step reaction. the synthesized compounds were structurally characterized using 1H-NMR, 13C-NMR, and IR spectra. Subsequently, the antitubercular activities of the compounds were determined against the M. tuberculosis H37Rv (ATCC 27294) standard strain using the agar proportion method. Results: Benzazole derivative compounds synthesized with reasonable yields (38-62%) exhibited antitubercular activity. the compounds were found effective against the M. tuberculosis H37Rv standard strain with MIC values ranging from 0.97 to 15.62 µg/ml at a 10-2 dilution. Conclusion: According to the results obtained from the study, especially the 4-methoxyphenyl (Compound 5) and non-substituted phenyl benzothiazole (Compound 4) derivatives were identified as the most active compounds. Compounds with these characteristics could serve as a basis for the development of new antituberculosis drugs.