缬氨酸Schiff碱和N,N’-杂环碱三元铜配合物的合成、 晶体结构及与BSA作用

合成了铜与水杨醛缩缬氨酸Schiff碱(salval)分别和1,10-菲咯啉(phen)及2,2’-联吡啶(bpy)形成的三元配合物Cu(salval)(phen)] (1), Cu(salval)(bpy)]•3H2O (2). 通过元素分析, 摩尔电导, IR, UV, TG-DTG对其进行了表征. 配合物2的结构经X射线单晶衍射确定, 三斜晶系, P-1空间群: a＝0.92676(3) nm, b＝1.03143(4) nm, c＝1.25042(3) nm; α＝74.108(2)°, β＝77.2240(10)°, g＝81.5880(10)°, V＝1.11642(6) nm3, Dc＝1.467 g•cm－3, Z＝2, F(000)＝514, 最后吻合因子R1＝0.0441, wR2＝0.0856 I＞2σ(I)]. 同时用荧光法研究了配合物与牛血清白蛋白(BSA)的相互作用. 结果表明, 两种配合物对BSA的荧光都有较强的猝灭作用, 静态猝灭是引起猝灭的主要原因. 在浓度比c配合物/cBSA为0～10范围内, 配合物1和配合物2在BSA上只有1个结合位点; 25 ℃结合常数KA分别为6.50×105 (1), 4.33×105 (2) L•mol－1; 给体(BSA)与受体(配合物)间的最近距离r分别为3.85 (1), 4.26 (2) nm. 说明两种配合物都能部分插入BSA分子内部, 且配合物1与BSA的作用强于配合物2.

Synthesis, Crystal Structure of Copper Complexes of DL-Valinato Schiff Base with N,N'-Heterocyclic Bases and the Interaction with BSA

Two copper ternary complexes of N-salicylidene-DL-valinato Schiff base with 1,10-phenan- throline Cu(salval)(phen)] (1) and 2,2’-bipyridine Cu(salval)(bpy)]•3H2O (2) were synthesized and characterized via elemental analysis, molar conductance, IR, UV and TG-DTG. The structure of 2 was determined by single crystal X-ray crystallography, which is of triclinic, space group P-1 with a＝0.92676(3) nm, b＝1.03143(4) nm, c＝1.25042(3) nm, α＝74.108(2)°, β＝77.2240(10)°, γ＝81.5880(10)°, V＝1.11642(6) nm3, Dc＝1.467 g•cm－3, Z＝2, F(000)＝514, R1＝0.0441 and wR2＝0.0856 I＞2σ(I)]. At the same time, the binding reaction between the complexes and bovine serum albumin (BSA) was studied by fluorescence spectroscopy. The research results indicated that the two complexes had a quite strong ability to quench the fluorescence from BSA and their combination reactions were mainly a static quenching process. The two complexes strongly bound BSA with a molar ratio of 1∶1 and the binding constant KA values at 25 ℃ were 6.50×105 (1) and 4.33×105 (2) L•mol－1, respectively. The shortest binding distance r between the donor BSA and acceptor of the ternary complexes were 3.85 (1) and 4.26 (2) nm, respectively, which affirms that the ternary complexes have partly inserted into the hydrophobic pocket of BSA and the interaction ability of complex 1 is stronger than that of complex 2.