Binding interaction, conformational change, and molecular docking study of N-(pyridin-2-ylmethylene)aniline derivatives and carbazole Ru(II) complexes with human serum albumins
Binding interaction, conformational change, and molecular docking study of N-(pyridin-2-ylmethylene)aniline derivatives and carbazole Ru(II) complexes with human serum albumins
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DOI：
10.1016/j.poly.2016.01.017
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发表时间：
2016-03-09
期刊：
影响因子：
2.6
通讯作者：
Omondi, Bernard
中科院分区：
文献类型：
--
作者：
Thangavel, Saravanan;Rajamanikandan, Ramar;Omondi, Bernard
新[RuCl2（1，5cod）（L1）]（1）、[RuCl2（1，5cod）（L2）]（2）、[RuCl2（1，5cod）（L3）1（3）、[RuCl2（1，5cod）（L4）]（4）、[RuCl2（1，5cod）（L5）]（5）（L =（p-R-N-（吡啶-2-基亚甲基）苯胺），R = H（L1），Cl（12），OCH 3（L3），CH 3（L4），L5 =合成了9-乙基-N-（吡啶-2-基亚甲基）-9H-咔唑-3-胺和1，5-cod = eta（4）-环辛烯配合物，并用H-1和C-13 NMR进行了表征，熔点分析、元素分析、HR-质谱、FT-IR和UV-Vis光谱。配合物1、2和3的单晶X-射线结构显示配体通过N原子以双齿的方式配位到Ru（II）中心。Ru（II）中心周围的几何构型为假八面体，两个Cl原子和环辛烯的π键占据配位位置。用紫外-可见光谱、同步发射光谱和圆二色光谱研究了钌配合物1-5与人血清白蛋白（HSA）的相互作用。结果表明，Ru（II）配合物1-5与HSA蛋白具有显著强的相互作用。配合物1、3和5的结合常数分别为1.77 × 10（5）dm（3）mol（-1）（1）、1.07 × 10（5）dm（3）mol（-1）（3）和1.07 × 10（5）dm（3）mol（-1）（5）。圆二色性（CD）研究揭示了在与复合物1-5相互作用后HSA内的α-螺旋含量降低，表明HSA二级结构的构象变化。通过分子对接研究，确定了HSA-Ru配合物的结合模式和配合物1-5在HSA中的结合能，进一步揭示了HSA中氨基酸残基对Ru（II）配合物结合的贡献。(C)2016爱思唯尔有限公司版权所有
New [RuCl2(1,5cod)(L1)] (1), [RuCl2(1,5cod)(L2)] (2), [RuCl2(1,5cod)(L3)1 (3), [RuCl2(1,5cod)(L4)] (4), [RuCl2(1,5cod)(L5)] (5) (L = (p-R-N-(pyridin-2-ylmethylene)aniline), R = H (L1), Cl (12), OCH3 (L3), CH3 (L4), L5 = (9-ethyl-N-(pyridin-2-ylmethylene)9H-carbazole-3-amine and 1,5cod = eta(4)-cyclooctadiene) complexes were synthesized and characterized by H-1 and C-13 NMR, melting point analysis, elemental analysis, HR-Mass spectrometry, FT-IR and UV-Vis spectroscopy. The single crystal X-ray structures of complexes 1, 2 and 3 revealed coordination of the ligands to the Ru(II) center in a bidentate manner via the N atoms. The geometry around the Ru(II) center is pseudooctahedral with the two Cl atoms and the pi-bonds of the cydooctadiene occupying the coordination sites. Interactions of Ru(II) complexes 1-5 with human serum albumins (HSA) were investigated using UV-Vis, synchronous emission and circular dichroism spectroscopy. The results demonstrated that the Ru(II) complexes 1-5 have significantly strong interaction with HSA proteins. Complexes 1, 3 and 5 showed moderate-to-high binding constants (K-b) 1.77 x 10(5) dm(3) mol(-1) (1), 1.07 x 10(5) dm(3) mol(-1) (3) and 1.07 x 10(5) dm(3) mol(-1) (5) respectively. Circular dichroism (CD) studies revealed decreased alpha-helix content within HSA upon interaction with complexes 1-5, suggesting a conformational change of the HSA secondary structure. Also, molecular docking studies were carried out to identify the binding models of the HSA-Ru complexes and binding energy of complexes 1-5 in HSA, which further revealed the contribution of amino acid residues of HSA in Ru(II) complex binding. (C) 2016 Elsevier Ltd. All rights reserved.