title: Synthesis, X-ray crystallography, spectroscopic characterization and spectroscopic/electrochemical evidence of formation of phenoxy free radical in active center analogs of galactose oxidase - [Cu(Salgly)H₂O] and [Cu(Salphenylalanine)H₂O].
abstract: The formation of phenolate free radical is the factor of high turnover for catalytic activity of galactose oxidase (GO) compared to that by inorganic complexes. A new active center analog of GO, [Cu(II)(Salphenylalanine)H(2)O] have been synthesized and its single crystal X-ray analysis was done. In aqueous surfactant micellar solution chemical oxidation as well as electrochemical oxidation of structural models of galactose oxidase - [Cu(II)Salgly·H(2)O] and [Cu(II)(Salphenylalanine)·H(2)O], have been found to generate free radical originating at the phenolate group. Formation of the free radical have been proved by electron paramagnetic resonance spectroscopy, electronic spectroscopy and electrochemistry.
authors.affiliation: Department of Chemistry, Gauhati University, Guwahati, Assam 781 014, India.
authors.forename: Biva
authors.initials: B
authors.lastname: Das
authors.forename: Okhil K
authors.initials: OK
authors.lastname: Medhi
mesh_terms: D020134:Catalytic Domain; D003300:Copper / Q000378:metabolism*; D018360:Crystallography, X-Ray; D055664:Electrochemical Techniques; D004578:Electron Spin Resonance Spectroscopy; D005692:Galactose Oxidase / Q000378:metabolism*; D008823:Micelles; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism*; D010636:Phenols / Q000378:metabolism*; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet
chemical_list: D008823:Micelles; D009942:Organometallic Compounds; D010636:Phenols; D012996:Solutions; C042329:phenoxy radical; D003300:Copper; D005692:Galactose Oxidase