Water-soluble tetraaqua Ln(III) glycinehydroximate 15-metallacrown-5 complexes towards potential MRI contrast agents for ultra-high magnetic field. (16th August 2016)

• Record Type: Journal Article
• Authors: Muravyeva, Maria S.; Zabrodina, Galina S.; Samsonov, Maxim A.; Kluev, Evgeny A.; Khrapichev, Alexandr A.; Katkova, Marina A.; Mukhina, Irina V.
• Is Part Of: Polyhedron. Volume 114(2016)
• Page Start: 165
• Page End: 171
• Publication Date: 2016-08-16
• Subjects: Polynuclear complexes -- Gadolinium -- Copper -- X-ray structure -- High field MRI; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2015.11.033
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: The tetraaqua lanthanide–copper 15-metallacrown-5 derivatives have been prepared. To assess the potential of Gd(H2 O)4 [15-MCCu(II)Glyha -5](Cl)3 complex as MRI contrast agent, the relaxivities were measured at 4.7 T, 7 T and 9.4 T high magnetic fields. Abstract: The tetraaqua lanthanide 15-metallacrown-5 Ln(H2 O)4 [15MCCuGlyha -5](Cl)3 complexes have been synthesized under ambient conditions from copper(II) acetate and lanthanide(III) chloride in water, using glycinehydroxamic acid as a ligand. The crystal structure has been solved for Gd(H2 O)4 [15-MCCu(II)Glyha -5](Cl)3 [1 (Gd)]. According to the X-ray diffraction study the Gd 3+ ion is coordinated by five oxygen atoms of the MC ring in the equatorial plane and four oxygen atoms of the water molecules in apical positions. The distances Gd–H(aq) are in the range 3.07(3)–3.10(3) Å. High relaxivity (>9.3 s −1 mM −1 ) has been confirmed by measurements at 4.7 T, 7 T and 9.4 T magnetic fields, that could presage its utility as a valuable platform for constructing high field MRI contrast agents.