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

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.

Synthesized compounds were characterized by Fourier-transform infrared, LC-MS, ¹H NMR and ¹³C 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 μg/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.

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.