[Spectra characteristics of the complexes of glucosamine and carboxymethyl glucosamine with ferrum(II), zinc(II), cobalt(II) and copper(II)].

This article investigated UV, IR and 1H-NMR spectra characteristics of the complexes which are formed by glucosamine and Fe (II), Zn (II), Co (II), Cu (II) respectively. The UV's lambda max of the complexes makes obvious violet shift when compared with that of the glucosamine. In IR spectra of the complexes, out-of-plane vibration peak 655 cm-1 of the amino group is lower than that of the glucosamine which is 670 cm-1, and there is also the new absorption peak near 990 cm-1. As for 1H-NMR, the C3 hydroxy proton and the amino proton of the complexes absorb highfield when compared with that of glucosamine, while the shifts of the hydroxy proton on other carbon atoms remain unchanged or almost unchanged, so the formation of the nitrogen-metal bond is primarily proved. This article also researched the syntheses of the complexes of the carboxymethyl glucosamine with Fe (II), Co (II), Cu (II) and pointed out that it is the rigidity of the sugar ring that leads to an abnormal phenomenon that the spectral lines' number of the complexes is the same as that of the carboxymethyl glucosamine. Their IR and UV spectra all indicate that there is no peak of the free carbonyl group in the molecule and prove the existence of inner salt. In the complexes' IR spectra, the formation of the oxygen-metal bond accounts for the appearance of a series of new absorption peaks: 433.1 and 408.9 cm-1 (O-Fe), 507.1 and 495 cm-1 (O-Co), 403.1 and 389 cm-1 (O-Cu).