Synthesis, chemical and biological studies on new Fe3+-glycosilated β-diketo complexes for the treatment of iron deficiency

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 Fe3+-complexes as oral iron supplements in the treatment of anaemia. The glycosilated compounds (6-GlcH, 6-GlcOH and 6-GlcOCH3) are characterized by means of spectroscopic (UV, 1H and 13C NMR) and potentiometric techniques; they have a good water solubility, are kinetically stable in physiological condition (t1/2 > 100 h) and show a low cytotoxicity also in high concentrations (IC50 > 400 μM). They are able to bind Fe3+ 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 Ca2+, and in particular 6-GlcOCH3 is able to inhibit lipid peroxidation.