ABSTRACT Some biogenic compounds undergo conformational isomerism, and the isomers may interact distinctively with other substances to form molecular complexes individually with different stabilities. In the present work, such molecular interaction specific to isomers was confirmed for the complexation of cationic glucosamine anomers with benzoate and phthalate anions. The individual stability constants of the anomer complexes were determined by tracing 1H NMR shifts of each anomer in titration with the appropriate carboxylate. In the complexes of benzoate, phthalate and terephthalate, the binding forces in the β-anomer complexes are two to five times as strong as those of the corresponding α-anomer complexes. The formulae of titration curves for determining individual stabilities have been developed in a generalised form to be applicable to the complexation of other unresolvable isomers with different compositions. Graphical abstract

中文翻译：

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阳离子氨基葡萄糖与苯甲酸盐和邻苯二甲酸盐的异构体特异性分子相互作用：通过 NMR 滴定检测无法解析的异构体复合物的个体稳定性

摘要 一些生物化合物存在构象异构现象，异构体可能与其他物质发生独特的相互作用，形成具有不同稳定性的分子复合物。在目前的工作中，这种对异构体具有特异性的分子相互作用已被证实用于阳离子氨基葡萄糖异头物与苯甲酸盐和邻苯二甲酸盐阴离子的络合。通过用合适的羧酸盐滴定每个端基异构体的 1 H NMR 位移来确定端基异构体复合物的个体稳定性常数。在苯甲酸酯、邻苯二甲酸酯和对苯二甲酸酯的配合物中，β-异头物配合物的结合力是相应的α-异头物配合物的二至五倍。用于确定个体稳定性的滴定曲线公式已以通用形式开发，适用于具有不同组成的其他无法解析的异构体的络合。图形概要