DTPA双酰胺杂环金属配合物的合成、表征及弛豫性能

Synthesis, Characterization and Relaxivity Property of DTPA Alkyl Esters Heterocyclic Metal Complexes

摘要:

通过酰化反应将一种新型杂环化合物 (HC)引入到二乙三胺五乙酸 (DTPA)结构中得到新型DTPA双酰胺杂环配体，再与Gd3 ，Mn2 以及Fe3 配位得到相应的功能配合物，作为潜在的磁共振成像造影剂。其结构通过FTIR，元素分析，1HNMR进行表征，并测定了配合物的纵向弛豫率 (longitudinal relaxivity, r1)。结果表明，Gd基配合物的r1 (13.20 mmol?L-1?s-1)和Mn基配合物的r1 (12.11 mmol?L-1?s-1)大大高于商业化医用的磁共振成像造影剂Gd-DTPA (r1=3.62 mmol?L-1?s-1)。通过等温滴定微量热法 (Isothermal titration calorimetry, ITC)测定了功能配合物与牛血清白蛋白(BSA)相互作用的热力学参数：Gd，Mn和Fe基配合物的结合常数Ka分别为1.17?06，2.91?05和4.04?04。

Abstract:

A new type of heterocyclic compound was introduced into diethylenetriamine pentaacetic (DTPA) by acylation reaction. The new ligand was then coordinated to Gd3 , Mn2 and Fe3 , respectively. The paramagnetic metal complexes were gained. The structures of heterocyclic compound, new DTPA ligand and metal complexes were characterized by FTIR, elemental analysis and 1HNMR. The longitudinal relaxivity (r1) was also measured. The results showed that the r1 of the Gd3 complex (13.20 mmol?L-1?s-1) and Mn2 complex (12.11 mmol?L-1?s-1) were both higher than that of MRI contrast agent Gd-DTPA (3.62 mmol?L-1?s-1) used in clinic. In addition, the thermodynamical parameters of the interaction between the metal complexes and bovine serum albumin (BSA) were conducted by isothermal titration calorimetry (ITC). The Ka of Gd complexes, Mn complexes and Fe complexes were determined to be 1.17?06, 2.91?05 and 4.04?04, respectively.