title: 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.
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
authors.forename: Valérie C
authors.initials: VC
authors.lastname: Pierre
authors.forename: Mauro
authors.initials: M
authors.lastname: Botta
authors.forename: Silvio
authors.initials: S
authors.lastname: Aime
authors.forename: Kenneth N
authors.initials: KN
authors.lastname: Raymond
mesh_terms: D003287:Contrast Media; D005682:Gadolinium / Q000737:chemistry*; D006860:Hydrogen Bonding; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011728:Pyridones / Q000737:chemistry*
chemical_list: D003287:Contrast Media; D011728:Pyridones; D005682:Gadolinium