锌(Ⅱ)-12-正戊基-1,4,7,10-四氮杂环十三烷-11,13二酮-α-氨基酸三元配合物的稳定性

Study on the Stability of Zn( II) -12 - Pentyl - 1,4,7,10 - tetraazacyclotridecane -11,13 - dione - a - amino Acids Ternary Complexes

合成了一种新的双氧四胺大环配体:12-正戊基-1,4,7,10-四氮杂环十三烷-11,13二酮(L).采用pH电位法,在(25±0.1)℃,I=0.1mol·dm^(-3)NaNO_3条件下,测定了锌(Ⅱ)与L的二元配合物及锌(Ⅱ)与L和六种α-氨基酸(AA=Gly,Ala,Val,Leu,IIe,Phe)形成的三元配合物的稳定常数.结合量子化学计算结果,讨论了在双氧四胺大环配体上引入疏水碳链形成具有双亲结构的配体后,与金属离子的配位能力的变化以及形成Zn(L)(AA)三元配合物稳定性变化规律.

New dioxotetraamine macrocycle (12 - pentyl - 1,4,7, 10 - tetraazacyclotridecane - 11, 13 -dione) was synthesized and characterized by elemental analysis, IR, 1H NMR and MS. By pH potentiometric titration at(25±0.1)℃, 1 = 0. 1mol·dm-3 NaNO3, the ligand protonation constants and the formation constants of the binary and ternary complexes with zinc were determined. The effect of pentyl group and stabilities of binary and ternary complexes are discussed with the aid of calculation using PM3 method.