Quinones resonance analysis

The oxidation of diols by quinolinium dichromate (QDC) shows a first-order dependence on QDC and acid.5 The oxidation of phenols to quinones by quinolinium dichromate in aqueous acetic acid is acid catalysed rate-determining formation of a cationic intermediate is indicated by a p value of —3.79 and further analysis shows the rates to be influenced equally by both inductive and resonance effects of the substituents.6... 

Wardman P, Dennis MF, Everett SA, Patel KB, Stratford MRL, Tracy M (2003) Radicals from one-electron reduction of nitro compounds, aromatic N-oxides and quinones the kinetic basis for hypoxia-selective, bioreductive drugs. Biochem Soc Symp 61 171-194 Warman JM, de Haas MP, Hummel A, van Lith D, VerberneJB, Loman H (1980) A pulse radiolysis conductivity study of frozen aqueous solutions of DNA. Int J Radiat Biol 38 459-459 Warman JM, de Haas MP, Rupprecht A (1996) DNA a molecular wire Chem Phys Lett 249 319-322 Warters RL, Lyons BW (1992) Variation in radiation-induced formation of DNA double-strand breaks as a function of chromatin structure. Radiat Res 130 309-318 Warters RL, Hofer KG, Harris CR, Smith JM (1977) Radionuclide toxicity in cultured mammalian cells Elucidation of the primary site of radiation damage. Curr Top Radiat Res Q 12 389-407 Weiland B, Huttermann J (1998) Free radicals from X-irradiated, dry and hydrated lyophilized DNA as studies by electron spin resonance spectroscopy analysis of spectral components between 77 K and room temperature. Int J Radiat Biol 74 341-358 Weinfeld M, Soderlind K-JM (1991) 32P-Postlabeling detection of radiation-induced DNA-damage identification and estimation of thymine glycols and phosphoglycolate termini. Biochemistry 30 1091-1097... 

While nuclear magnetic resonance spectroscopy has become an invaluable tool in lignin analysis, relatively little effort has been directed toward the calculation of such spectra for lignin model compounds. Liptaj et al. [68] compared conformational data for cinnamaldehyde models derived from NMR to calculation, and similar work on quinone methides at both semiempirical and ab initio levels has been reported by Konschin et al. [69]. 

In the amine oxidase from Escherichia coli, the topa quinone was confirmed by a detailed analysis of the cofactor dipeptide X-Asp [67] and the resonance Raman spectrometry of the enzyme and its derivatives[68,69]. The primary structure of the enzyme also contains the cofactor consensus sequence [70]. More bacterial genes were shown to encode proteins containing the topa quinone consensus sequence, such as amine oxidase from Klebsiella aerogenes [71], phenethylamine oxidase and histamine oxidase from Arthrobacter globiformis [72,73], and methylamine oxidase from Arthrobacter strain PI [74]. Amino acid sequences around the position of the cofactor for selected amine oxidases from various sources are given in Table 1. 

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