Synthesis, characterization and biological screening of pyrazole-conjugated benzothiazole analogs

Aim: Benzothiazole and pyrazoles are two important pharmacophores, the activity can be enhanced by conjugating them. Here, two novel series of the pyrazole-conjugated benzothiazole derivatives were synthesized. Results: Synthesized compounds were characterized by Fourier-transform infrared, LC-MS, H-1 NMR and C-13 NMR spectroscopic techniques. Synthesized compounds exhibited moderate antimicrobial, antioxidant and excellent anti-TB activities. In in vitro anti-TB activity, 4d and 4e exhibited 1.6 mu g/ml minimum inhibitory concentration value. In order to rationalize the anti-TB activity, molecular docking studies were carried out and they were correlated with the in vitro results. Conclusion: Compounds containing electron donating groups show the promising antimicrobial and antioxidant activities, compounds with CH3 and Cl substitution show excellent anti-TB activity. Synthesized molecules may become potential candidates for the clinical trials.