新型双卤代吡啶酰腙的合成及生物活性研究

以2-氯吡啶-4-甲酸甲酯(1)和水合肼缩合生成2-氯吡啶-4-甲酰肼(2),2与卤代(F,Cl,Br)对苯甲醛反应得到3种新型双卤代吡啶酰腙[C13H9N3OFCl(3a),C13H9N3OCl2(3b)和C13H9N3OClBr(3c)],其结构经1H NMR,13C NMR,IR和元素分析表征。紫外光谱证实,3a^3c与小牛胸腺DNA(ct-DNA)均产生了插入作用。荧光光谱显示,3a^3c均与牛血清蛋白BSA通过静态猝灭形成了复合物。3a^3c与ct-DNA,BSA的结合常数Kb及KA的关系均为3b>3c>3a。抑菌测试结果表明:3种酰腙化合物对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌及铜绿假单胞菌等4种细菌的抑菌圈均超过8 mm。其中,3a对4种细菌的最大抑菌圈达10.97 mm。

Synthesis and Biological Activities of Novel Double Halogenated Pyridine Acylhydrazones

2-chloropyridine-4-carboxylic acid hydrazide(2)was synthesized by the condensation reaction of 2-chloropyridine-4-carboxylic acid methyl ester(1)and hydrazine hydrate.Three novel double halogenated pyridine acylhydrazones[C13H9N3OFCl(3 a),C13H9N3OCl2(3 b)and C13H9N3OClBr(3 c)]were synthesized by the reaction of 2 with halogenated benzaldehydes(F,Cl,Br).The structures were characterized by 1H NMR,13C NMR,IR and elemental analysis.UV spectra showed that 3a^3c reacted with calf thymus DNA(ct-DNA)through the modes of insertion.Fluorescence spectra showed that 3a^3c reacted with bovine serum albumin BSA to form a complex by static quenching effect.The sequences of binding constants Kb and KA were all 3 b>3 c>3 a.Antibacterial properties showed that the inhibition zone of three compounds reacting with Escherichia coli,Staphylococcus aureus,Bacillus subtilis and Pseudomonas aeruginosa could reach more than 8 mm,indicating 3a^3c had certain antibacterial ability against four bacteria.Among them,the maximum inhibition zone of 3 a against four bacteria was 10.97 mm and the minimum inhibitory concentration of each compound was 0.25 mg·mL^-1.