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, ¹H-NMR, ¹³C-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.

摘要

N-取代双吡唑啉由双查尔酮与N-取代氨基硫脲衍生物在碱性条件下反应合成。1-(2,5-二甲基噻吩-3-基)乙烷-1-酮与对苯二甲醛在碱性条件下反应合成双查耳酮。双吡唑啉衍生物的结构已通过FT-IR、¹ H-NMR、¹³ C-NMR、ESI-MS等光谱技术得到证实，化合物的纯度已通过元素分析得到证实。体外的这些吡唑啉衍生物对两种革兰氏阳性和两种革兰氏阴性菌株的抗菌活性通过圆盘扩散法和最低抑菌浓度（MIC）法进行评估，并将结果与​​标准药物阿莫西林进行比较。构效关系表明，硫代甲酰基上具有氯芳族取代基的化合物比标准药物阿莫西林具有更高的活性。