Pierre Valérie C, Botta Mauro, Aime Silvio, Raymond Kenneth N
Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
J Am Chem Soc. 2006 Apr 26;128(16):5344-5. doi: 10.1021/ja057805x.
Eight-coordinate hydroxypyridinone/terephthalamide GdIII complexes display high relaxivities due to their two inner sphere water molecules. This relaxivity can be further increased by functionalizing the terephthalamide moiety with an amine. A significant hydrogen bonding interaction between the amine and another water molecule close to the GdIII apparently facilitates its coordination on the open site of the metal. The resulting nine-coordinate complex has three inner sphere water molecules, while maintaining high stability and fast ligand exchange rates.
八配位的羟基吡啶酮/对苯二甲酰胺钆（III）配合物由于其两个内界水分子而具有高弛豫率。通过用胺对苯二甲酰胺部分进行功能化，可以进一步提高这种弛豫率。胺与靠近钆（III）的另一个水分子之间存在显著的氢键相互作用，这显然促进了其在金属开放位点上的配位。所得的九配位配合物有三个内界水分子，同时保持高稳定性和快速的配体交换速率。
