Synthesis and Antibacterial Activity of (E)-N'-[4-{2-(4-Fluorophenylthio)ethoxy}-3-cyano-5-methoxybenzylidene]-substituted benzohydrazide Derivatives
作者:Lokamaheshwari Dommati、B. Satyanarayana、P. Gayatri Hela、B. Ram、G. Srinivas
DOI:10.14233/ajchem.2016.19776
日期:——
Commercially available vanillin was used as the starting material for the preparation of some new (E)-N’-[4-2-(4-fluorophenylthio)-ethoxy}-3-cyano-5-methoxybenzylidene]-4-substituted benzohydrazide derivatives (8.1 to 8.10) in quantitative yields. The structural confirmations of all the newly synthesized hydrazone derivatives were established on the basis of 1H NMR, mass and IR data. Hydrazides such as (E)-N’-[4-2-(4-fluorophenylthio)ethoxy}-3-cyano-5-methoxybenzylidene]-2,5-dichlorobenzohydrazide (8.6), (E)-N’-[4-2-(4-fluorophenylthio)ethoxy}-3-cyano-5-methoxybenzylidene]-2,5-difluorobenzohydrazide (8.9) showed duplication of NMR signals, this was attributed to the presence of anti and syn periplanar conformers. Antibacterial study against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa with reference to the standard drug (streptomycin) revealed that compounds bearing R = 4-OH (8.2), 3,4,5-OMe (8.3) and 4-SO2Me (8.4) substituents has shown the good antibacterial sensitivity.
以市售的香草醛为起始原料,制备了一系列新型的(E)-N’-[4-2-(4-氟苯硫基)乙氧基}-3-氰基-5-甲氧基亚苄基]-4-取代苯甲酰肼衍生物(8.1至8.10),产率为定量。所有新合成的脎衍生物的结构确认基于1H NMR、质谱和红外数据。例如(E)-N’-[4-2-(4-氟苯硫基)乙氧基}-3-氰基-5-甲氧基亚苄基]-2,5-二氯苯甲酰肼(8.6)和(E)-N’-[4-2-(4-氟苯硫基)乙氧基}-3-氰基-5-甲氧基亚苄基]-2,5-二氟苯甲酰肼(8.9)显示出NMR信号的重复,这归因于反式和顺式periplanar构象的存在。针对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌和铜绿假单胞菌的抗菌研究,参考标准药物(链霉素),结果显示含有R=4-OH(8.2)、3,4,5-OMe(8.3)和4-SO2Me(8.4)取代基的化合物表现出良好的抗菌敏感性。