| Popis: |
Eight novel diamino-ester ligands were synthesized by amidation reaction of long-chain alkyl esters of l-lysine with diethylenetriamine pentaacetic acid monoanhydride or ethylenediamine tetraacetic acid monoanhydride. The corresponding dimeric Gd(iii) complexes were obtained by treating these ligands with GdCl3·6H2O. All ligands and complexes were characterized by 1H NMR, FT-IR, and elemental analysis. The longitudinal relaxation time (T1) was measured, and all relaxivity values (R1) of these dimeric Gd(iii) complexes are higher than that of Magnivest (Gd-DTPA). One of these complexes, possessing the highest relaxivity in the DTPA series, was chosen to test the acute toxicity and T1-weighted imaging. It was found that this dimeric Gd(iii) complex exhibits no acute toxicity, and offers highly enhanced MRI signal and increases intention time in the rat liver tissue compared to Magnivest. |
