对双胍基苯甲酰化壳聚糖盐酸盐的制备及其抗菌活性研究

Synthesis and antibacterial activitiy of p-biguanido benzoyl chitosan hydrochloride

在盐酸溶液中,对氨基苯甲酸与双氰胺反应合成了中间体对双胍基苯甲酸盐酸盐;该中间体再与氯化亚砜反应得双胍基苯甲酰氯。后者在甲磺酸体系中与壳聚糖进行酰化反应制得对双胍基苯甲酰壳聚糖盐酸盐。考察了酰化时间、温度及反应物投料比等对壳聚糖衍生物取代度的影响,并采用UV,IR,1HNMR对产物进行了表征。抗菌实验表明,该产物对大肠杆菌、金黄色葡萄球菌最低抑菌浓度分别为0.016和0.008 mg/mL,其抗菌活性优于壳聚糖和对双胍基苯甲酸盐酸盐,且随浓度的增大而增强。

The intermediate 1-（p-carboxyphenyl） biguanidine hydrochloride（p-CPBGH） was synthesized by p-aminobenzoic acid（PABA） as raw material,reacting with dicyandiamide in the presence of hydrochloric acid.Then p-CPBGH was reacted with thionyl chloride forming p-biguanido benzoyl chloride.The latter was reacted with chitosan in methylsulfonic acid as the reaction medium forming p-biguanido benzoyl chitosan hydrochloride（p-BGBCH）.Effects of reaction time,reaction temperature and molar ratio of chitosan to p-CPBGH on the degree of substitution in the chitosan derivative were investigated.The product was characterized by UV,IR and 1HNMR.The antibacterial activity test results indicated that the minimum inhibitory concentration values of the product to E.coli and S.aureus achieves 0.016 and 0.008 mg/mL respectively.It was also found that the antibacterial activity of the product was stronger than that of chitosan and p-CPBGH.