Design, synthesis, characterization and antitubercular activity of some nov-el 2, 4-disubstituted thiazole derivatives

Literature reviews reveal that thiazole and pyrazine carboxamide derivatives exhibit anticonvulsant, antimicrobial, anticancer and anti-tubercular activities due to the presence of –S-C=N- and-CO–NH- moiety. A series of thiazolyl pyrazine carboxamide derivatives (5a-j) were synthesized by condensation reaction between 2-amino, 4-substituted phenyl 2-amino thiazole and pyrazine 2-carboxylic acid. These synthesized thiazole derivatives (5a-j) were evaluated for their inhibitory activity against Mycobacterium tuberculosis (Mtb), H37Rv using microplate Alamar Blue assay (MABA). The compound, 5c and 5h showed high anti-mycobacterial activity with MIC value of 6.25 µg/ml, and the compound 5g also exhibited anti-mycobacterial activity with MIC value of 12.50 µg/ml. Molecular docking studies of these synthesized molecules with b-Ketoacyl-ACP Synthase (KasA) protein of Mycobacterium tuberculosis (Mtb) have been carried out to understand the mechanism of anti-mycobacterial action.