Potentiometric, spectrophotometric and calorimetric study on iron(III) and copper(II) complexes with 1,2-dimethyl-3-hydroxy-4-pyridinone.
The iron(III)-1,2-dimethyl-3-hydroxy-4-pyridinone (Deferiprone) system is carefully characterized by a combined potentiometric-spectrophotometric procedure at 25 and 37 degrees C at different ionic strengths, and by thermochemical and quantum-chemical studies. The main purpose of this work was to determine how the temperature dependence of both complex-formation and protonation constants can affect the pFe values on going from 25 degrees C (pFe is normally calculated using 25 degrees C stability constants) to the physiological temperature of 37 degrees C at which chelating agents are active in vivo. The copper(II)-Deferiprone system is also studied and the iron(III)-Deferiprone distribution diagrams in presence of variable copper(II) amounts are shown so as to explain possible side effects due to a competing metal ion during the chelating therapy of iron overload.
Nurchi
Valeria M
VM
Dipartimento di Scienze Chimiche, Università di Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato-Cagliari, Italy. nurchi@unica.it
Crisponi
Guido
G
Pivetta
Tiziana
T
Donatoni
Martina
M
Remelli
Maurizio
M
D002151:Calorimetry / Q000379:methods*; D003300:Copper / Q000737:chemistry*; D000077543:Deferiprone; D004563:Electrochemistry / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry*; D011728:Pyridones / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*
D005290:Ferric Compounds; D011728:Pyridones; D000077543:Deferiprone; D003300:Copper