Gd-complexes of macrocyclic DTPA conjugates of 1,1′-bis(amino)ferrocenes as high relaxivity MRI blood-pool contrast agents (BPCAs)

Abstract

We report the synthesis of macrocyclic DTPA conjugates of 1,1'-bis(amino)ferrocenes (1a-b) and their Gd-complexes [Gd(L)(H(2)O)] (2a-b, L = 1a-b) for use as new MRI blood-pool contrast agents. High R(1) relaxivity in HSA as well as high thermodynamic and kinetic stabilities is observed for 2a.