Antibacterial activity of N-benzylsalicylthioamides.

The in-vitro biological activity of N-benzylsalicylthioamides against 8 bacterial strains was determined by broth microdilution method; results were compared with those obtained with neomycin, penicillin G, ciprofloxacin and penicillin V. The compounds showed moderate to high activity against G(+) bacteria; especially compounds 4, 6, 13, 16-21 and 24 exhibited comparable or higher activity than reference drugs. The antibacterial activity was analyzed by quantitative structure-activity relationship (QSAR). The antibacterial activity increased with lipophilicity, with the presence of halogens and with increasing value of Hammet substituent constant σ.