Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland.
Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland.
Int J Mol Sci. 2024 Aug 23;25(17):9137. doi: 10.3390/ijms25179137.
The mode of coordination of copper(II) ions with dopamine (DA, L) in the binary, as well as ternary systems with Ado, AMP, ADP, and ATP (L') as second ligands, was studied with the use of experimental-potentiometric and spectroscopic (VIS, EPR, NMR, IR)-methods and computational-molecular modeling and DFT-studies. In the Cu(II)/DA system, depending on the pH value, the active centers of the ligand involved in the coordination with copper(II) ions changed from nitrogen and oxygen atoms (CuH(DA), Cu(DA)), via nitrogen atoms (CuH(DA)), to oxygen atoms at strongly alkaline pH (Cu(DA)). The introduction of L' into this system changed the mode of interaction of dopamine from oxygen atoms to the nitrogen atom in the hydroxocomplexes formed at high pH values. In the ternary systems, the ML'-L (non-covalent interaction) and ML'HxL, ML'L, and ML'L(OH)x species were found. In the Cu(II)/DA/AMP or ATP systems, mixed forms were formed up to a pH of around 9.0; above this pH, only Cu(II)/DA complexes occurred. In contrast to systems with AMP and ATP, ternary species with Ado and ADP occurred in the whole pH range at a high concentration, and moreover, binary complexes of Cu(II) ions with dopamine did not form in the detectable concentration.
采用实验电位法和光谱（VIS、EPR、NMR、IR）方法以及计算分子建模和 DFT 研究，研究了铜（II）离子与多巴胺（DA，L）在二元以及与 Ado、AMP、ADP 和 ATP（L'）作为第二配体的三元体系中的配位模式。在 Cu（II）/DA 体系中，根据 pH 值的不同，与铜（II）离子配位的配体的活性中心从氮和氧原子（CuH（DA），Cu（DA）），通过氮原子（CuH（DA）），在强碱性 pH 值下转变为氧原子（Cu（DA））。将 L'引入该体系改变了多巴胺的相互作用模式，从氧原子转变为在高 pH 值下形成的羟合配合物中的氮原子。在三元体系中，发现了 ML'-L（非共价相互作用）和 ML'HxL、ML'L 和 ML'L（OH）x 物种。在 Cu（II）/DA/AMP 或 ATP 体系中，混合形式在 pH 约为 9.0 之前形成；在该 pH 以上，仅发生 Cu（II）/DA 配合物。与含有 AMP 和 ATP 的体系不同，在整个 pH 范围内，在高浓度下会出现与 Ado 和 ADP 的三元物种，而且，在可检测浓度下，不会形成 Cu（II）离子与多巴胺的二元配合物。
