Hydroxypyridinone derivatives

The situation is further confused by qualitative observations, such as the conflicting views as to the solubilizing effect or otherwise of the CH2OH group in kojates and derived hydroxypyridinonates (238). In relation to Table XVIII, the trend of increasing solubility from water to ethanol followed by a steady decrease to 1-decanol, common to ethylmaltol and its iron complex, resembles that established for Fe(bipy)2(CN)2 and Fe(phen)2(CN)2, though in the case of these... 

Many hydroxyp5rranones and hydroxypyridinones and their metal complexes have been of importance in analytical chemistry, solvent extraction, and metal separation. Here their excellent chelating properties in conjunction with the possibility of synthesizing strongly lipophilic derivatives make this class of ligands particularly useful. 

Iron(III) complexation by 5-nitrotropolone follows the usual mechanistic pattern, 4 at Fe +, at FeOH +aq. Dinuclear Fe2(OH)2 aq, like FeOH +aq, reacts by an mechanism. Curcumin (232) and its diacetyl derivative form complexes with Fe + whose stabilities approach that of Fe -desferrioxamine, hence their suggested use for treatment of iron overload—a topic which dominates the following section devoted to two specific classes of hydroxyketones, viz hydroxypyranones and hydroxypyridinones. ... 

An oxidative coupling reaction of hydroxypyridinones with /5-dicarbonyl compounds leads to the formation of dihydrofuro[3,2- ]pyridinone derivatives (Equation 48) <2005TL5085>. The reaction is carried out as a one-pot synthesis. 

TABLE 4. Complexes derived from hydroxypyrones, hydroxypyridinones and related species ... 

A series of hydroxypyridinone tripods has been used as metal chelators. The derivative (125) has been prepared by carboxylation of l-methyl-3-hydroxy-2(lH)-pyridinone under... 

An intramolecular Wacker oxidation of allyl hydroxypyridinone gave rise to furopyridinone derivatives in excellent yields <05JOC8055>. 

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