Synthesis of novel N-(naphthalen-1-yl)propanamide derivatives and evaluation their antimicrobial activity

New N-(naphthalen-1-yl)propanamide was synthesized and studied for their antimicrobial activity. The final compounds were procured by reacting N-(naphthalen-1-yl)propanamide with some 2-mercapto aryl or dithiocarbamate salt derivatives. Their structures were determined by 1H-NMR and 13C-NMR spectroscopy and LC-MS/MS spectral data. The synthesized compounds were investigated for their antimicrobial activities against 10 bacteria and 10 fungi species. All compounds showed notable activity. Especially, compounds 2-[(5-methyl-1,3,4-thiadiazol-2-yl)thio]-N-(naphthalen-1-yl)propanamide (2a), 2-(benzothiazol-2-ylthio)-N-(naphthalen-1-yl)propenamide (2b), 2-[(1-methyl-1H-imidazol-2-yl)thio]-N-(naphthalen-1-yl)propanamide (2c), and N-(naphthalen-1-yl)-2-[(5-nitro-1H-benzimidazol-2-yl)thio]propanamide (2e) exhibited antifungal activity against at least one fungus at the half potency of ketoconazole. Also, 2-[(1-methyl-1H-imidazol-2-yl)thio]-N-(naphthalen-1-yl)propanamide (2c), N-(naphthalen-1-yl)-2-[(5-nitro-1H-benzimidazol-2-yl)thio]propanamide (2e) and 2-[(4-methyl-4H-1,2,4-triazol-3-yl)thio]-N-(naphthalen-1-yl)propanamide (2f) showed anti-gram-positive bacterial activity at the half potency of chloramphenicol. Only one compound, 2-(benzothiazol-2-ylthio)-N-(naphthalen-1-yl)propanamide (2b) displayed anti-gram-negative bacterial activity against Yersinia enterocolitica (Y53).