Abstract
N-substituted bis-pyrazolines were synthesized by the reaction of bis-chalcone with N-substituted thiosemicarbazide derivatives under basic conditions. Bis-chalcone was synthesized by the reaction of 1-(2,5-dimethylthiophen-3-yl)ethan-1-one with terephthalaldehyde under basic condition. The structure of the bis-pyrazoline derivatives has been confirmed by spectroscopic techniques such as FT-IR, H-1-NMR, C-13-NMR, and ESI-MS spectra, and the purity of the compound has been confirmed by the elemental analysis. The in vitro antibacterial activity of these pyrazoline derivatives was estimated against two Gram-positive and two Gram-negative bacterial strains by the disk diffusion method and minimum inhibitory concentration (MIC) method and the results were compared with standard drug Amoxicillin. The structure-activity relationship shows that the compound with choloro aromatic substituents at thiacarbomoyl group was more active than standard drug Amoxicillin.