Synthesis, reaction, and metal-chelating property of
N-hydroxyamide-containing heterocycles such as 1-hydroxy-2 (1
H) -pyrimidinones and -pyrazinones are described. The diazines showed remarkable high water solubility and acidity, which enable them to act as an effective acylating agent for amines, amino acids, and alcohols. The diazines were also found to be an bidentate ligand to a ferric iron in aqueous solution, in particular, under acidic to neutral conditions. The five types of tripodal hexadentate ligands bearing 1-hydroxy-2 (1
H) -pyrimidinone or -pyrazinone as bidentate ligands were synthesized, and effects of their structural feature and the chirality on their metal-chelating behavior were also discussed. Among them, a hexadenate ligand bearing 1-hydroxy-2 (1
H) -pyrazinone, L-alanine, and tris (2-aminoethyl)amine showed high iron removal ability from human transferrin, and its pseudo-first-order-rate constant was more than five times greater than naturally-occurring siderophore, desferrioxamine B, even in small excess of the ligand concentration to transferrin.
View full abstract