title: Copper-containing monooxygenases: enzymatic and biomimetic studies of the O-atom transfer catalysis.
abstract: This review reports our recent studies or the mechanism of O-atom transfer to a benzylic C-H bond promoted by Dopamine beta-Hydroxylase (DBH) and its biomimetic models. We demonstrate that it is possible to carry out parallel and comparative studies on this enzyme (DBH) and its biomimetic models with the same substrate: 2-aminoindane (3). It was chosen because its two stereogenic centers, both in benzylic positions, make it very powerful for studying the stereochemistry of an O-atom transfer reaction. DBH-catalyzed hydroxylation of 3 produced exclusively 14% of trans-(1S,2S)-2-amino-1-indanol (4) (93% ee). Studies with stereospecifically deuterium-labeled 2-aminoindanes (1R,2S)-3b and (1S,2S)-3a showed that the formation of 4 was the rcsult of an overall process with retention of configuration where an O-atom is stereospecifically inserted in the trans pro-S position of the substrate. With copper(I) and (II) complexes of IndPY2 ligands we studied the reaction with dioxygen and observed an O-atom transfer to a benzylic C-H bond which was performed in the same manner as that of DBH. With the deuterium-labeled cis-2-d-IndPY2 ligand, we demonstrated that the reaction occurs by a stereospecific process with retention of configuration. In both cases (enzymatic vs. biomimetic) the O-atom transfers occur in a two-step process involving radical intermediates.
authors.affiliation: Faculté des Sciences et Techniques de Saint Jérĵme, Chimie, Biologie et Radicaux Libres, UMR-CNRS, Universités d'Aix-Marseille, Escadrille Normandie-Niemen, Marseille, France.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Blain
authors.forename: Patrick
authors.initials: P
authors.lastname: Slama
authors.forename: Michel
authors.initials: M
authors.lastname: Giorgi
authors.forename: Thierry
authors.initials: T
authors.lastname: Tron
authors.forename: Marius
authors.initials: M
authors.lastname: Réglier
mesh_terms: D000595:Amino Acid Sequence; D001554:Benzene / Q000378:metabolism; D001665:Binding Sites; D002384:Catalysis; D003300:Copper / Q000737:chemistry* / Q000378:metabolism*; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism; D006900:Hydroxylation; D006899:Mixed Function Oxygenases / Q000378:metabolism*; D008956:Models, Chemical; D008958:Models, Molecular; D018716:Molecular Mimicry; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D003300:Copper; D006899:Mixed Function Oxygenases; D004299:Dopamine beta-Hydroxylase; D001554:Benzene; D010100:Oxygen