The binding of oxovanadium(IV) to simple sugars in neutral or basic aqueous solution, as studied by EPR and electronic absorption spectroscopy, is reported. The complexation is favored in basic media and involves the coordination of the metal ion to couples of adjacent deprotonated hydroxyls of the sugar molecule. However, only the ligands provided with cis couples can adopt this chelating ligand behavior. The ability of the cis hydroxyl couples to yield chelated complexes has been related to the structural rearrangement (decrease of the O-C-C-O torsion angle in the five-membered chelated ring) needed to permit the oxovanadium(IV) coordination by the sugar molecule.
OXOVANADIUM(IV) COMPLEX-FORMATION BY SIMPLE SUGARS IN AQUEOUS-SOLUTION / Branca, M; Micera, Giovanni; Dessi, A; Sanna, D.. - In: JOURNAL OF INORGANIC BIOCHEMISTRY. - ISSN 0162-0134. - 45:3(1992), pp. 169-177. [10.1016/0162-0134(92)80042-T]
OXOVANADIUM(IV) COMPLEX-FORMATION BY SIMPLE SUGARS IN AQUEOUS-SOLUTION
MICERA, Giovanni;
1992-01-01
Abstract
The binding of oxovanadium(IV) to simple sugars in neutral or basic aqueous solution, as studied by EPR and electronic absorption spectroscopy, is reported. The complexation is favored in basic media and involves the coordination of the metal ion to couples of adjacent deprotonated hydroxyls of the sugar molecule. However, only the ligands provided with cis couples can adopt this chelating ligand behavior. The ability of the cis hydroxyl couples to yield chelated complexes has been related to the structural rearrangement (decrease of the O-C-C-O torsion angle in the five-membered chelated ring) needed to permit the oxovanadium(IV) coordination by the sugar molecule.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
