白氨酸-谷氨酸甲酯-谷氨酸共聚物的合成研究

Preparation of Leucine-methyl Glutamate-glutamic Acid Copolymers

本文研究了白氨酸－谷氨酸甲酯－谷氨酸共聚物的合成方法，先对谷氨酸进行苄酯和甲酯保护，再与光气溶液反应制备氨基酸酯的羧酸酐，共聚合，随后用溴化氢脱酯，由停放时间来控制游离侧羧基含量。红外光谱和紫外吸光度分析表明，反应失去绝大部分的苄基和部分的甲基。与溴化氢作用的时间越长，脱苄的程度越高，游离侧羧基含量越大，其亲水性越强。

The method for preparing leucine-methyl glutamate-glutamic acid copolymer was studied. In thefirst place benzyl glutamate and methyl glutamate were synthesized respectively. Then N-carboxy anhydrides(NCA) of leucine, benzyl glutamate or methyl glutamate were prepared in a closed container by phosgene-toluenesolution method-After copolymerization the copolymers were debenzylated and demethylated by anhydrous hydro-gen brcmide. The free carboxyl group mole content in side chains of the copolymer was controlled by variousstanding periods following bubbling HBr. Analysis of infrared spectrogram and ultraviolet asorbance of copolymersindicated that this procedure resulted in the loss of almost all benzyl groups and some methyl groups.