New 4-Thiazolidinones of Nicotinic Acid with 2-Amino-6-methylbenzothiazole and their Biological Activity

The title compounds 6a–j, 2-[(6-methyl-1,3-benzothiazol-2-yl)amino]-N- [2-(substituted phenyl/furan-2-yl)-4-oxo-1,3-thiazolidin-3-yl]nicotinamides, were prepared from 2-chloropyridine-3-carboxylic acid (1) and 2-amino-6-methylbenzothiazole (2) by known methods. All the compounds have been established by IR, ¹H NMR, ¹³C NMR and elemental analyses. The in vitro antimicrobial screening of the compounds were carried out against two Gram positive (S. aureus, S. pyogenes), two Gram negative (E. coli, P. aeruginosa) bacteria and three fungal species (C. albicans, A. niger, A. clavatus) using the broth microdilution method. Some of the compounds are comparable with standard drugs.