title: Modulation of Phenol Oxidation in Cofacial Dyads.
abstract: The presentation of two phenols on a xanthene backbone is akin to the tyrosine dyad (Y730 and Y731) of ribonucleotide reductase. X-ray crystallography reveals that the two phenol moieties are cofacially disposed at 4.35 Å. Cyclic voltammetry reveals that phenol oxidation is modulated within the dyad, which exhibits a splitting of one-electron waves with the second oxidation of the phenol dyad occurring at larger positive potential than that of a typical phenol. In contrast, a single phenol appended to a xanthene exhibits a two-electron process, consistent with reported oxidation pathways of phenols in acetonitrile. The perturbation of the phenol potential by stacking is reminiscent of a similar effect for guanines stacked within DNA base pairs.
authors: Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors: Bon Jun
authors: BJ
authors: Koo
authors: Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors: Michael
authors: M
authors: Huynh
authors: Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors: Robert L
authors: RL
authors: Halbach
authors: Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors: JoAnne
authors: J
authors: Stubbe
authors: Department of Chemistry and Chemical Biology, Harvard University , 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors: Daniel G
authors: DG
authors: Nocera
mesh_terms: D004579:Electron Transport; D008958:Models, Molecular; D008968:Molecular Conformation; D019800:Phenol / Q000737:chemistry*; D012264:Ribonucleotide Reductases / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry; D014966:Xanthenes / Q000737:chemistry*
chemical_list: D014966:Xanthenes; D019800:Phenol; D014443:Tyrosine; D012264:Ribonucleotide Reductases