Iron(III) and aluminum(III) complexes with hydroxypyrone ligands aimed to design kojic acid derivatives with new perspectives.
With the aim to design new chelators for the clinical treatment of different diseases involving the trivalent metal ions Fe(III) and Al(III), we present the equilibria of kojic acid and its derivative 6-[5-hydroxy-2-hydroxymethyl-pyran-4-one]-5-hydroxy-2-hydroxymethyl-pyran-4-one with these two metal ions. Potentiometric and spectrophotometric techniques for iron, and potentiometry and (1)H NMR for aluminum were used, supported by X-ray, electrospray ionization-mass spectrometry (ESI-MS), calorimetry and quantum chemical calculations. In this work, evidence is given on the formation of MeL, MeL(2), and MeL(3) complexes of both metal ions with kojic acid, confirmed by the X-ray structure of the FeL(3) complex, and of variously protonated Me(2)L(2) and MeL(2) complexes of 6-[5-hydroxy-2-hydroxymethyl-pyran-4-one]-5-hydroxy-2-hydroxymethyl-pyran-4-one. The extremely good pFe value for this second ligand gives confidence to, and opens perspectives for, the search of new kojic acid derivatives.
Nurchi
Valeria Marina
VM
Dipartimento di Scienze Chimiche, Università di Cagliari, 09042 Monserrato, Cagliari, Italy. nurchi@unica.it <nurchi@unica.it>
Crisponi
Guido
G
Lachowicz
Joanna Izabela
JI
Murgia
Sergio
S
Pivetta
Tiziana
T
Remelli
Maurizio
M
Rescigno
Antonio
A
Niclós-Gutíerrez
Juan
J
González-Pérez
Josefa María
JM
Domínguez-Martín
Alicia
A
Castiñeiras
Alfonso
A
Szewczuk
Zbigniew
Z
D000535:Aluminum / Q000737:chemistry*; D000975:Antioxidants / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006801:Humans; D007501:Iron / Q000737:chemistry*; D008024:Ligands; D008969:Molecular Sequence Data; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors; D019906:Nuclear Magnetic Resonance, Biomolecular; D011753:Pyrones / Q000737:chemistry*
D000975:Antioxidants; D002614:Chelating Agents; D008024:Ligands; D011753:Pyrones; C011890:kojic acid; D000535:Aluminum; D007501:Iron; D014442:Monophenol Monooxygenase