爱魔域

与组胺-铜 (II) 系统相比，魔域前期攻略通过可见光吸收、质子和 C-13 NMR 光谱方法研究了铜 (II) 离子和大量过量组氨酸之间的络合。根据可见光区的光谱数据，主要物质被认为是 a=0 时的 ML2H+ 和 ML2H22+ 和 a=1 和 2 时的 ML2，其中 a 代表每摩尔双质子化配体添加的碱摩尔数。在 ML2H+ 中，一个组氨酸与组胺样结合，在顶端位置配位羧酸盐，另一个甘氨酸样与质子化咪唑基团结合，而在 ML2H22+ 中，两个组氨酸分子都与甘氨酸样结合。两个组氨酸分子在 ML2 中均与顶端羧酸盐呈三齿状。在组胺-铜 (II) 系统中，在 a=1 和 2 处暗示了顶端位置的第三个组胺分子的配位。鉴于上述情况，对质子和 G-13 核磁共振谱进行了合理解释。在他的...之间观察到 PMR 信号的线加宽差异。

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Complexation between Copper(II) Ion and Large Excess Histidine in Aqueous Solution

The complexation between copper(II) ion and large excess histidine has been studied by visible absorption, proton and C-13 NMR spectral methods, in comparison with histamine–copper(II) system. The predominant species were considered to be ML2H+ and ML2H22+ at a=0 and ML2 at a=1 and 2, respectively from the spectral data in visible region, where a represents moles of base added per mole of diprotonated ligand. In ML2H+, one histidine is bound histamine-like with a carboxylate coordinated in apical position and the other glycine-like with a protonated imidazolium group, and in ML2H22+, both histidine molecules are bound glycine-like. Two histidine molecules are both tridentate with apical carboxylates in ML2. In histamine–copper(II) system, the coordination of the third histamine molecule in the apical position was suggested at a=1 and 2. The proton and the G-13 NMR spectra were reasonably interpreted in view of the above situation. A difference in the line-broadening of PMR signals was observed between his...