Synthesis and characterization of new β-diketo derivatives with iron chelating ability

Here we report the synthesis, the characterization and a theoretical study on new glycosylated phenyl substituted β-diketones; two classes of compounds are obtained according to the condensation reaction: central and side derivatives. Their iron(III) chelating ability is tested by means of UV–visible (UV–vis), potentiometric and NMR techniques. The conformation of central derivatives does not allow any metal chelation, while side derivatives bind iron(III) through the β-dioxo moiety. The glycosyl moiety does not interact with metal ion but it helps to stabilize metal/ligand (1/3) complexes by means of hydrophylic interactions. The pKa of the ligands and the stability constants of their Fe(III) complexes are evaluated by means of UV–vis spectroscopy and potentiometry. A comparison with other iron-chelating agents, on the basis of lipophilicity and the pFe(III), is finally reported.