5-溴-邻羟苯基芳基取代酰腙的合成、表征及抑菌活性研究

以水杨酸甲酯为原料，先经溴化反应制得5-溴水杨酸甲酯，再经肼解反应制得5-溴-2-羟基苯甲酰肼，再与取代芳香醛缩合反应，制得7种5-溴-2-羟基苯甲酰基取代芳醛腙，其中3种为新化合物。 化合物的结构经IR、¹H NMR、MS与元素分析测试技术表征确证。 抑菌测试表明，该类化合物对不同菌株的抑菌活性具有明显的选择性；在质量浓度为0.05%时，上述化合物对白色念珠菌、枯草芽孢杆菌的抑菌率高达100%，具有强抑菌活性，是一类极具潜力的抗真菌、抗革兰氏阳性菌的化合物。 5-溴-2-羟基苯基-3′,5′-二溴-2-羟基苯甲醛腙的抗菌活性接近广谱高效杀菌剂三氯生。 构效分析表明，化合物的抑菌活性与Ar环及其取代基性质有关，引入呋喃环、Ar环邻、对位引入-OH、-OCH₃等供电基容易导致化合物抑菌活性降低，Ar环的间位引入Cl、Br等卤素原子能够提高化合物的抑菌活性。

Synthesis, Characterization and Antibacterial Activities of 5-bromo-o-hydroxyphenyl aryl substitute hydrazones

A series of bromo-o-hydroxyphenyl substituted hydrazones were synthesized by combining the molecule segment o-hydroxyphenyl with hydrazone derivatives according to antibacterial characteristics of o-hydroxydiphenyl ethers and hydrazone compounds. Seven 5-bromo-o-hydroxyphenyl substituted hydrazones were synthesized by using methyl salicylate as raw material, through bromination, hydrazination and condensation reactions, respectively.The structures of all the compounds have been confirmed by 1H NMR、IR、mass spectra and element analysis. The result of preliminary bioassay shows that the title compounds have obvious specificity antibacterial activities to different classificatory bacterium at 0.05%(mass concentration), and have 100% inhibitory ratio on Monilia albican and Bacillus subtilis. They will be a kind of potential antibacterial compounds in fungus and Gram-positive bacteria. The 5-bromo-o-hydroxyphenyl-3′,5′-dibromo-o-hydroxyphenyl hydrazone has the same antibacterial activities as triclosan. The analysis of structure activity show that antibacterial activities relate to the kind of Ar-ring and its substituent groups. The antibacterial activities were reduced by electron-donating groups, such as o-,p-OH、-OCH3, of Ar-ring, however, they were enhanced by the m-substituted halogen groups of Ar-ring.