D-氨基葡萄糖与锌盐配位的红外光谱研究

研究了不同pH值下，D-氨基葡萄糖与硫酸锌的配位情况。随着pH值的逐渐增大，氨基葡萄糖与金属锌离子的配位能力越来越强，pH6．5时D-氨基葡萄糖与硫酸锌有最大配位比，其配比为1：1。同时还合成了氨基葡萄糖与不同锌盐的配合物，通过旋光度、摩尔电导、锌含量和IR的分析，表明在相同条件下，不同锌盐与氨基葡萄糖形成的配合物，其配位方式不同。

Study on D-Glucosamine-Zn(Ⅱ) Complexes by IR Spectral Analysis

In this paper, a series of glucosamine-Zn(II) complexes were synthesized by the reaction of D-glucosamine hydrochloride with ZnSO4 at different pH values. The physical properties and the IR spectra of glucosamine-ZnSO4 complexes were investigated. The absorption at 3346 and 3292 cm(-1) shifted to 3300 cm(-1) due to O--H and N--H stretching, one at 1617 cm(-1) shifted to 1530 cm(-1) due to N-H stretching, and one at 1094 cm(-1) disappeared due to secondary alcohol --OH stretching. But 1033 cm(-1) with primary alcohol --OH did not shift, suggesting that both the amino and secondary hydroxyl groups of glucosamine are coordinated to Zn(II). The results showed that the coordination ability of Zn(II) to glucosamine was enhanced with the pH value increasing, however, the coordination ability weakened when pH value was more than 6.5. So pH 6.5 is an optimal coordination condition for glucosamine-ZnSO4 complexes. The complexes of D-glucosamine with different zinc salts (zinc sulfate, zinc nitrate, zinc acetate, and zinc chloride) were also synthesized at the same pH value, and zinc chloride had weaker coordination ability than other zinc salts. Their IR spectra indicated that glucosamine-Zn(II) complexes with different zinc salts had different coordination model, and only glucosamine-ZnSO4 complex had fixed ratio of coordination under the condition of pH 6.5. The structure of the complex seems to correspond to Zn(glucosamine)]SO4 7H2O at pH 6.5.