PH-Potentiometric Investigation towards Chelating Tendencies of p-Hydroquinone and Phenol Iminodiacetate Copper(II) Complexes. (3rd May 2010)

• Record Type: Journal Article
• Authors: Stylianou, Marios; Keramidas, Anastasios D.; Drouza, Chryssoula
• Other Names: Perlepes Spyros P. Academic Editor.
• Is Part Of: Bioinorganic chemistry and applications. Volume 2010(2010)
• Publication Date: 2010-05-03
• Subjects: Bioinorganic chemistry -- Periodicals; Bioinorganic chemistry; Biochemistry; Inorganic Chemistry; Chemistry, Bioinorganic; Periodicals; 572.51
• DOI: 10.1155/2010/125717
• Languages: English
• ISSNs: 1565-3633

Abstract

Abstract : Copper ions in the active sites of several proteins/enzymes interact with phenols and quinones, and this interaction is associated to the reactivity of the enzymes. In this study the speciation of theCu 2 + with iminodiacetic phenolate/hydroquinonate ligands has been examined by pH-potentiometry. The results reveal that the iminodiacetic phenol ligand forms mononuclear complexes withCu 2 + at acidic and alkaline pHs, and a binuclearO phenolate -bridged complex at pH range from 7 to 8.5. The binucleating hydroquinone ligand forms only 2 : 1 metal to ligand complexes in solution. The pK values of the protonation of the phenolate oxygen of the two ligands are reduced about 2 units after complexation with the metal ion and are close to the pK values for the copper-interacting tyrosine phenol oxygen in copper enzymes.