Abstract
Fourteen(Z)-2-(2-oxo-1-((arylamino)methyl)indolin-3-ylidene)-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2 yl)hydrazine-1-carboxamides 4a-4n were prepared by treating (Z)-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)-2-(2-oxoindolin-3-ylidene)hydrazine-1-carboxamide 3 with the aryl amines and formaldehyde. The chemical structures of these compounds were elucidated by their physical constants, spectral data and elemental analysis. These compounds were investigated for their antimicrobial activity against five Gram-positive bacteria, namely, S. aureus, E. faecalis, S. epidermidis, B. subtilis and B. cereus; five Gram-negative bacteria, namely, E. coli, P. aeruginosa, K. pneumoniae, B. bronchiseptica and P. vulgaris; and five fungi, namely, C. albicans, A. niger, A. flavus, M. purpureous and P. citrinum by serial plate dilution method using standard drugs, ofloxacin and ketoconazole, respectively, and their minimum inhibitory concentrations (MICs) were also determined. These compounds showed mild to moderate antibacterial activity against Gram positive as well as Gram negative bacteria. However, they exhibited better antifungal activity. The compound 4j (Ar = 1,2,4-Triazol-4-yl) has been identified as the most promising antifungal agent of this series. There is a possibility that the replacement of triazole ring by other azole ring. e.g. imidazole and 1,2,3-triazole; and / or the presence of halogen substituted coumarin ring may produce promising potent antimicrobial agents that are effective against Gram positive bacteria, Gram negative bacteria and fungi.