[Gd(CyPic3A)(H2O)2]−: a stable, bis(aquated) and high-relaxivity Gd(iii) complex

Abstract

We report the synthesis and MR relevant properties of CyPic3A, a heptadentate chelator that forms ternary Gd(III) complexes of hydration state q = 2. [Gd(CyPic3A)(H₂O)₂]⁻ affords an r₁ value of 5.70 mM⁻¹ s⁻¹ at 1.41 T and 310 K and displays thermodynamic stability and kinetic inertness comparable to FDA approved MR imaging probes.