The crystal structure of a valinomycin•2Ca 2+ complex and the multi-step solution equilibria in acetonitrile characterised by 1 H NMR, UV–Vis, and mass spectrometry
The crystal structure of a valinomycin•2Ca 2+ complex and the multi-step solution equilibria in acetonitrile characterised by 1 H NMR, UV–Vis, and mass spectrometry
复制标题
缬氨霉素·2Ca 2 配合物的晶体结构以及通过 1 H NMR、UV-Vis 和质谱表征的乙腈多步溶液平衡
DOI：
10.1080/10610278.2016.1186276
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发表时间：
2016
影响因子：
3.3
通讯作者：
Khan, Farooq A.
中科院分区：
文献类型：
--
作者：
Contractor, Alisha A.;Kazerouni, Amaan M.;Michmerhuizen, Anna R.;Falkenberry, Margaret L.;Segovia, Rigoberto;Blair, Nicholas M.;Kim, SeongEun;Vander Griend, Douglas A.;Bacsa, John;Khan, Farooq A.
缬氨霉素是一种众所周知的钾选择性离子载体，但其与钙离子（另一种生物学上重要的阳离子）直接相互作用的性质也引起了相当大的兴趣。我们确定了缬氨霉素-钙复合物的第一个晶体结构，该复合物仅以 1:2 缬氨霉素:Ca2+复合物的形式结晶，[VCa2(OTf)2(H2O)2]2+ 呈固态（V = 缬氨霉素，OTf = 三氟甲磺酸酯）。与 1:2 配合物一起，通过 1H NMR 和 UV-Vis 滴定实验对乙腈中的溶液相 1:1 和 2:1 配合物进行了表征。这些复合物的摩尔吸光率曲线和结合平衡常数已通过使用 SIVVU™ 程序对 UV-Vis 滴定数据进行全局分析来确定。
Valinomycin is a well-known potassium-selective ion carrier, but the nature of its direct interaction with calcium ion, another biologically important cation, is also of considerable interest. We have determined the first crystal structure of a valinomycin–calcium complex, which crystallises exclusively as a 1:2 valinomycin:Ca2+complex, [VCa2(OTf)2(H2O)2]2+in the solid state (V = valinomycin, OTf = triflate). Along with the 1:2 complex, the solution phase 1:1 and 2:1 complexes have been characterised in acetonitrile by1H NMR and UV–Vis titration experiments. The molar absorptivity curves and binding equilibrium constants for these complexes have been determined by the global analysis of the UV–Vis titration data using the program SIVVU™.