铜(Ⅱ)-氨基葡萄糖-α-氨基酸三元配合物的稳定性

Stability of Glucosamine-α-aminoacids-copper(Ⅱ) Ternary Complexes

为研究铜(Ⅱ)-氨基葡萄糖-α-氨基酸三元配合物的稳定性,用pH电位滴定法测定了298±0.1 K,I=0.10 mol/L KNO3条件下铜(Ⅱ)-氨基葡萄糖-α-氨基酸三元配合物的稳定常数。结果表明,在铜(Ⅱ)-氨基葡萄糖-α-氨基酸三元体系中,生物配体氨基葡萄糖和α-氨基酸具有良好的相容性,三元配合物的稳定性与α-氨基酸的碱性及二元配合物稳定性之间存在直线自由能关系。

To study the stability of glucosamine-α-aminoacids-copper（Ⅱ） ternary complexes,the formation constant of α-aminoacids-glucosamine-copper（Ⅱ） ternary complexes were determined at 298 K,I=0.1 mol/L KNO3 by pH method.It was found that the two biologically active ligand,α-aminoacid and glucosamine accommodate each other when coordinated to copper（Ⅱ） ion.The stability of the ternary complexes is higher than that of the corresponding binary complex.The formation constant of the ternary complexes linearly increases with increase of the protonation constant of aminoacid and the stability of its binary complexes.Linear free energy relationship（LFER） does exist in the ternary system.