NMR STUDY OF METAL-ION COMPLEXATION

金属离子络合的核磁共振研究

• 批准号: 3438919
• 负责人: ANTHONY FRATIELLO
• 金额: $ 9.98万
• 依托单位: CALIFORNIA STATE UNIVERSITY LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-05-01 至 1994-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3438919
• 关键词: anions; carboxylate; cations; deuterium; ionophores; lanthanum; metal complex; molecular shape; monensin; nuclear magnetic resonance spectroscopy; solvents; stoichiometry

This project will involve the application of nuclear magnetic resonance (NMR) spectroscopy to the study of metal-ion complexes of the carboxylic ionophores, lasalocid A and monensin, in aqueous solvent mixtures. The long-range objective are the quantitative evaluation of the stoichiometry and the resultant net charge of the complex; the specific binding sites in the ionophore and the geometry of the complex; the specific binding sites in the ionophore and the geometry of the complex, that is, whether the metal-ion is surrounded or binds at an outer site only; the effect of metal-ion size and coordinating propensity on the type of complex formed; and the influence of anion complexing ability. The metal-ions to be used are trivalent lanthanum, lutetium, and yttrium, all strong complexing agents varying in size, and electronic and magnetic properties. A multinuclear approach using hydrogen-1, carbon-13, nitrogen-14, chlorine- 35, yttrium-89, and lanthanum-139 NMR spectroscopy will be applied in this structural study. The experiments will involve the direct observation of separate sets of resonance signals for bound and free ionophore, a condition made possible by the dissociation of its complex and subsequent ligand exchange slow enough on the NMR time scale. The objective of the project will be attained by hydrogen-1 chemical shift, relaxation time, and signal area determinations, along with chemical shift and relaxation time experiments for the other nuclei planned for study.

该项目将涉及核磁共振的应用 (NMR) 光谱法研究羧酸金属离子配合物 离子载体、拉沙里菌素 A 和莫能菌素，在水性溶剂混合物中。 这 长期目标是化学计量的定量评估 以及综合体的最终净电荷；中的特定结合位点 离子载体和络合物的几何形状；特异性结合位点 在离子载体和络合物的几何形状中，即是否 金属离子仅被包围或结合在外部位点；的效果 金属离子的大小和对形成的络合物类型的配位倾向； 以及阴离子络合能力的影响。 使用的金属离子 是三价镧、镥和钇，均为强络合 试剂的尺寸、电子和磁性各不相同。 一个 使用氢1、碳13、氮14、氯-的多核方法 35、钇 89 和镧 139 NMR 光谱将应用于此 结构研究。 实验将涉及直接观察 结合和游离离子载体的独立共振信号组， 通过其复杂和随后的解离而成为可能的条件 配体交换在核磁共振时间尺度上足够慢。 该计划的目标 项目将通过氢1化学位移、弛豫时间和 信号面积测定，以及化学位移和弛豫时间 计划研究的其他核的实验。