Synthesis and Evaluation of Heterocyclic Scaffold-Based Styrene Conjugates as New Antibacterial Agents

The conjugation of different substituted styryl (-CH=CH-Aryl) moieties with the biologically relevant heteroaromatic scaffolds such as 4-benzylidene-2-methyloxazol-5-one, 3-methyl-1-phenylpyrazol-5-one, 2-methylbenzimidazole, 6-methyluracil afforded the newer series (four different series, 1A-3C, 2A-C, 3A-C & 4A-C) of styrene derivatives. Newer styrene derivatives were synthesized and characterized by IR, NMR (1H & 13C), Mass spectroscopic/spectrometric methods and elemental analysis. Results of the antibacterial activity study reveal that the synthesized compounds possess in-vitro activity against the tested bacterial strains, which, however, was comparatively very less than that of the standard drug, amikacin sulphate. From the structure-activity relationship study, it could be attributed that the overall antibacterial efficacy of the conjugated series of styrene derivatives is the sum of bio-effectiveness of styryl moieties and heterocyclic scaffolds.