O-季铵化低聚壳聚糖芳香醛席夫碱衍生物的制备及其抑菌活性

Study on Synthesis and Antibacterial Activity of O-Quaternized N-Aryl Chitooligosaccharides Schiff's Base Derivatives

以低聚壳聚糖为对象,苯甲醛、水杨醛、香草醛为改性试剂,设计合成了一系列O-季铵盐低聚壳聚糖芳香醛席夫碱衍生物。产物元素分析发现其席夫碱取代度接近100%,电位滴定确定产物的季铵盐接枝率在35%左右。抑菌活性研究表明,合成的各种O-季铵盐低聚壳聚糖芳香醛席夫碱衍生物抑菌活性明显增强,活性大小依次为香草醛改性物>水杨醛改性物>苯甲醛改性物>低聚壳聚糖。抑菌活性构效关系分析表明,低聚壳聚糖通过芳香醛席夫碱改性引入了酚羟基抑菌活性中心,但酚羟基的抑菌活性受空间位阻影响较大。

The N-aryl chitooligosaccharides （COS） derivatives were synthesized from benzaldehyde, salicylal and vanillin, and subsequently grafted with N-（3-chloro-2-hydroxy propyl） trirnethyl ammonium chlo- ride. According to the C/N element analysis, the extent of N-substitution of all COS Schiff derivatives was almost closed to 100% and the degree of quaternization was about 35%. The antibacterial activity results showed N-vanillin Schiff base COS〉N-salicylal Schiff base COS〉N-benzaldehyde Schiff base COS〉 COS. The analysis on the structure and activity relationship of COS derivatives showed that the phenol hy- droxyl group from N-aryl Schiff COS was the center of antibacterial activity, but its activity was restricted by steric hindrance.