Ferric maltol

The non-toxic 3-hydroxypyrones (Structure 12) bind iron(III) forming water-soluble complexes [44], In the pH range 4-7, they possess a lower affinity for iron(III) than EDTA, and by virtue of the kinetic lability of such complexes, are able to donate iron to high-affinity binding sites, while minimizing non-selective binding to foodstuffs. Thus, iron presented as a maltol complex is relatively well absorbed [103,104], In contrast, the presence of EDTA reduces iron absorption by the intestine. Ferric maltol is the only simple iron(III) preparation which compares favourably with iron(II) sulphate [105], and in contrast to iron(II) sulphate, there are few, if any, side effects associated with the oral administration of ferric maltol. Consequently, patient compliance is likely to be superior with this iron preparation. 

Maltol is a good chelating agent and various metal complexes, e.g., aluminum maltol and ferric maltol have heen investigated as potentially useful therapeutic or experimental agentsd ... 

Singh RK, Barrand MA. Lipid peroxidation effects of a novel iron compound, ferric maltol. A comparison with ferrous sulfate. J Pharm Pharmacol 1990 42 276—279. 

Kelsey SM, Hider RC, Bloor JR, et al. Absorption of low and therapeutic doses of ferric maltol, a novel ferric iron compound, in iron deficient subjects using a single dose iron absorption test. J Clin Pharm Ther 1991 16 117—122. 

This coloration may, however, be due to maltol derived from torrefied malt. If, then, the reaction with ferric chloride is obtained, a portion of the aqueous solution of the residue from the ethereal extract should be tested with Millon s reagent2 a red coloration indicates salicylic acid, whilst no coloration shows that the reaction with ferric chloride is due to maltol. 

When subjected to alkaline hydrolysis streptomycin yields maltol, 2-methyl-3-hydroxy-y-pyrone, quantitatively and this fact may be used in the assay of streptomycin, the maltol being determined either spectro-photometrically (maximum absorption at 322 m//) or colorimetrically (after reaction with ferric iron to give a purple-red colour). Dihydrostreptomycin will not yield maltol under the conditions given below so that streptomycin can be determined in its presence as, for example, in Streptoduocin for Injection, U,S.P, which contains equal amounts of the two antibiotics. 

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