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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.

The NMR study on the interaction of Pt(II) with Amadori compounds is performed. The Amadori compounds are derived from the reaction of β- d -glucose with l -cystine leading to N,N′-di-(1-deoxy-β-fructos-1-yl)- l -cystine [FruCyscys], and with l -methionine leading to N-(1-deoxy-β-fructos-1-yl)- l -methionine [FruMet]. The great instability of 2-(1,2,3,4,5-pentahydroxypentyl)-1,3-thiazolidine-4-carboxylic acid [GlcCys], formed by the condensation reaction of β- d -glucose and l -cysteine, prevents the formation of its Pt(II) complexes. Differently, FruMet well reacts with K2PtCl4 in 1:1 M/L molar ratio leading to the formation of [Pt(FruMet-N,S)Cl2], in which the Amadori compound coordinates the metal ion through nitrogen and sulphur atoms. FruMet originates also a solid trans complex [Pt(FruMet-N,S)2]Cl2. Its NMR solution study allowed to identify two isomers with respect to nitrogen and sulphur atoms: R,R and S,S. In [Pt2FruCyscysCl4] species, FruCyscys molecule links two Pt(II) ions giving rise to two pentaatomic N,S-chelate rings.

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.