The synthesis and relaxivity of a new gadolinium(III) complex of a polyazatricarboxylate macrocycle (DOTVA) having 2bromoisovaleric acid pendant arm is reported. The longitudinal relaxivity (r1p) of [Gd(DOTVA)(H2O)] is 6.72 mM-1 s-1 (20 MHz, 37 ± 0.1 °C, pH 7) which is higher than that of [Gd(DOTA)(H2O)]- (r1p = 4.2 mM-1 s-1, 20 MHz)by 1.6% than the clinically approved CAs. The r2p/r1p ratio for Na[Gd(DOTVA)(H2O)] is 1.16 showing that the complex is a T1-weighted contrast agent. The complexes show pH dependent relaxivity at low and high pH values. It forms adduct with HSA and shows relaxivity enhancement.  The 2bromoisovaleric acid seems to be an excellent pendant arm functionality in making new CAs for MRI and the amide core is a versatile core molecule for the creation of polynuclear gadolinium(III) chelates and dendrimeric CAs.  

Key words -  MRA Contrast agents, Blood Pool Agents, MRI, 2-bromoisovaleric acid, DOTVA