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Tuning the coordination number of hydroxypyridonate-based gadolinium complexes: implications for MRI contrast agents.

ABSTRACT: 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.

SUBMITTER: Pierre VC

PROVIDER: S-EPMC3188315 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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Tuning the coordination number of hydroxypyridonate-based gadolinium complexes: implications for MRI contrast agents.

Pierre Valérie C VC Botta Mauro M Aime Silvio S Raymond Kenneth N KN

Journal of the American Chemical Society 20060401 16

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, wh ...[more]

PMID: 16620097

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