Abstract: Synthesis and characterization of the ligand, [10-(α-tetradecylcarboxymethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid, H4L] and its Gd(Ⅲ) chelate are described. Protonation constants for H4L(lgKiH = 10.62, 9.50, 4.74, 4.12) and the stability constant for GdL-(lgKGdL-= 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. |