Design, synthesis, and biological evaluation of 2,6-diaminobenzobisthiazole derivatives as promising antimicrobial and antiviral agents with molecular docking insights into DNA gyrase targeting

The emergence of drug-resistant pathogens necessitates the development of novel antimicrobial and antiviral agents. In this study, a series of 2,6-diaminobenzobisthiazole derivatives were synthesized and evaluated for their antimicrobial and antiviral activities. The antimicrobial screening revealed that compounds 4, 6, 10, and 20 exhibited potent activity against Gram-positive ( S. aureus ) and Gram-negative ( E. coli , P. aeruginosa ) bacteria, with minimum inhibitory concentrations (MICs) as low as 3.125 µg/mL, comparable to standard antibiotics such as chloramphenicol. Additionally, these compounds demonstrated significant antifungal effects against C . albicans , highlighting their broad-spectrum potential. Antiviral assessments against the H5N1 virus demonstrated that compounds 3 and 4 achieved 91% and 87% inhibition, respectively, at 0.25 µM concentration, suggesting promising antiviral efficacy. Molecular docking studies further validated the biological activity, revealing strong interactions between potent compounds and Pseudomonas aeruginosa DNA gyrase (PDB: 3TYE), supporting their potential mechanism of action. Overall, this study highlights the promising therapeutic potential of 2,6-diaminobenzobisthiazole derivatives as potent antimicrobial and antiviral agents, warranting further investigation for clinical applications.