Synthesis and characterization of the ligand,[10-( α -tetradecylcarboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid,H 4 L]and its Gd (Ⅲ) chelate are described.Protonation constants for H 4 L(lgK iH =1...Synthesis and characterization of the ligand,[10-( α -tetradecylcarboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid,H 4 L]and its Gd (Ⅲ) chelate are described.Protonation constants for H 4 L(lgK iH =10.62,9.50,4.74,4.12)and the stability constant for GdL - (lgK GdL - =24.60)were determined by potentiometric titrations.The results obtained show that the basicity of the ligand is not significantly altered and the ligand still maintains the strong chelating properties of the parent DOTA after introduction of a linear chain tetradecyl group at the acetic side chain of DOTA.展开更多
文摘Synthesis and characterization of the ligand,[10-( α -tetradecylcarboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid,H 4 L]and its Gd (Ⅲ) chelate are described.Protonation constants for H 4 L(lgK iH =10.62,9.50,4.74,4.12)and the stability constant for GdL - (lgK GdL - =24.60)were determined by potentiometric titrations.The results obtained show that the basicity of the ligand is not significantly altered and the ligand still maintains the strong chelating properties of the parent DOTA after introduction of a linear chain tetradecyl group at the acetic side chain of DOTA.