SYNTHESIS AND PROTON RELAXIVITY OF GD-EDD S AND GD-THEC

Two amino acid derivative ligands, ethylenediamine-N,N'-disuccinic aci d(EDDS) and N,N,N',N'-tetrahydroxyethylcystine (THEC), were synthesize d from the reaction of L-aspartic acid with 1,2-dibromoethane and L-cy stine with chloroethanol respectively. Their paramagnetic gadolinium ( III) complexes were prepared by the reaction of the ligands with Gd2O3 and Gd(OAc)(3) respectively. The ligands and their Gd(III) complexes were characterized by IR, H-1 NMR spectroscopy and elemental analysis. The proton relaxivity of the complexes was investigated, and the R(1) values of Gd(III)-EDDS and Gd(III)-THEC are 10.33 and 6.62 mmol(-1). L . s(-1), respectively.