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The Fe3+ chelating ability of some curcumin glucosyl derivatives (Glc-H; Glc-OH; Glc-OCH3) is tested by means of UV and NMR study. The pK a values of the ligands and the overall stability constants of Fe3+ and Ga3+ complexes are evaluated from UV spectra. The only metal binding site of the ligand is the β-diketo moiety in the keto-enolic form; the glucosyl moiety does not interact with metal ion but it contributes to the stability of metal/ligand 1:2 complexes by means of hydrophilic interactions. These glucosyl derivatives are able to bind Fe3+ in a wide pH rage, forming complex species thermodynamically more stable than those of other ligands commonly used in the treatment of iron deficiency. In addition they demonstrate to have a poor affinity for competitive biological metal ions such as Ca2+. All ligands and their iron complexes have a good lypophilicity (log P > −0.7) suggesting an efficient gastrointestinal absorption in view of their possible use as iron supplements in oral therapy. The ligand molecules are also tested for their antioxidant properties in “ex vivo” biological system.

A simple synthetic pathway to obtain glycosilated β-diketo derivatives is proposed. These compounds show a good iron(III) affinity therefore we may suggest the use of their Fe 3+ -complexes as oral iron supplements in the treatment of anaemia. The glycosilated compounds (6-GlcH, 6-GlcOH and 6-GlcOCH 3 ) are characterized by means of spectroscopic (UV, 1 H and 13 C NMR) and potentiometric techniques; they have a good water solubility, are kinetically stable in physiological condition ( t 1/2 > 100 h) and show a low cytotoxicity also in high concentrations (IC 50 > 400 μM). They are able to bind Fe 3+ ion in acid condition (pH ∼ 2) forming complex species thermodynamically more stable than those of other ligands commonly used in the treatment of iron deficiency. The iron complexes show also a good kinetic stability both in acidic and physiological pH and have a good lypophilicity (log P > −0.7) that suggests an efficient gastrointestinal absorption in view of their possible use in oral therapy. In addition they demonstrate a poor affinity for competitive biological metal ion such as Ca 2+ , and in particular 6-GlcOCH 3 is able to inhibit lipid peroxidation.

Here we report the first evidence of Pt(II) interaction with Amadori compound [N-(1-deoxy- d -Fructos-1-yl)glycine (Fru-Hgly)]. The 1H and 195Pt NMR results show that complexation of Pt(II) by Fru-Hgly is strongly dependent on pH and reaction molar ratio. In 1/1 Pt/Fru-Hgly molar ratio, at acidic pH, the first coordination site is the carboxylic oxygen, while at physiological pH the anchoring group is the aminic one, in both cases the system slowly evolves towards an N,O chelating mode. In 1/2 Pt/Fru-Hgly molar ratio the only coordination site is nitrogen atom while the carboxylic oxygen is not involved in metal coordination.

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.

A solution study on the ability of some derivatised sugars [glucuronic acid (GluA), galacturonic acid (GalA) and glucosaminic acid (GlNA)] to complex the Hg(II) ion is reported. The stability constants of the complex species were determined by potentiometric measurements while 1H NMR experiments allow to define the coordination sites of sugar molecules. GluA coordinates the metal ion through the carboxylic oxygen and the O-4 hydroxyl group and is found to form more stable complexes with respect to GalA in which metal ligation is from the carboxylic oxygen and the O-5 ring oxygen. GlNA forms stable complexes chelating Hg(II) ion through carboxylic oxygen and the α-amino group. The ternary 2,2′-bipyridine containing systems were also investigated by means of potentiometric studies. The ML2 complexes were also isolated in the solid state and characterised by IR spectroscopy.