L-赖氨酸长链烷基酯双DTPA酰胺钆(Ⅲ)配合物的合成、表征与弛豫效能

Synthesis,Characterization and Relaxivity of Dimeric DTPA-Gadonium(Ⅲ) Complexes with Long Chain Alkyl Esters of L-Lysine

通过二乙三胺五乙酸单环酸酐(DTPA-MA)分别与L-赖氨酸的十八酯、十六酯、十四酯和十二酯的双酰化反应,制得四种含有双DTPA螯合单元的新型配体。它们与GdCl3.6H2O配合得到相应的双核钆(Ⅲ)配合物。表征了配体和配合物的结构,测试了配合物的纵向弛豫效能(R1)。结果表明:这四种新钆配合物的R1都高于Gd-DTPA。

To look for new MRI （magnetic resonance imaging） contrast agents with higher relaxivity as well as liver-selecsivity, four novel ester-amino ligands were synthesized by bis-acylation of octadecanyl, hexadecanyl, tetradecanyl and dedecanyl L-lysine with diethylenetriaminepentaacetic acid mono-anhydride （DTPA-MA）, respectively. The corresponding dimeric Gd（ Ⅲ） complexes were gained by the reaction of these ligands with GdCl3·6H2O. All ligands and complexes were characterized by FTIR, 1H NMR and elemental analysis. The longitudinal relaxation time （T1） was measured, and relevant longitudinal relaxivity （R1） of these neatral binuclear Gd （Ⅲ） complexes is ： 6. 48, 6. 02, 5.76 and 5.68 L · mmol^-1 · s^-1, respectively, and all are higher than that of Gd-DTPA （4. 98 L ·mmol^-1·s^-1 ） （300 MHz）.