583-63-1Relevant articles and documents
Kinetic characterization of the oxidation of chlorogenic acid by polyphenol oxidase and peroxidase. Characteristics of the o-quinone
Munoz,Garcia-Molina,Varon,Rodriguez-Lopez,Garcia-Ruiz,Garcia-Canovas,Tudela
, p. 920 - 928 (2007)
Chlorogenic acid is the major diphenol of many fruits, where it is oxidized enzymatically by polyphenol oxidase (PPO) or peroxidase (POD) to its o-quinone. In spectrophotometric studies of chlorogenic acid oxidation with a periodate ratio of [CGA]0/[lO4-]0 0/[IO4-]0 > 1, the o-quinone was characterized as follows: λmax at 400 nm and ε = 2000 and 2200 M-1 cm-1 at pH 4.5 and 7.0, respectively. In studies of o-quinone generated by the oxidation of chlorogenic acid using a periodate at ratio of [CGA]0/[lO4-]0 > 1, a reaction with the remaining substrate was detected, showing rate constants of k = 2.73 ± 0.17 M-1 s-1 and k = 0.05 ± 0.01 M-1 s-1 at the above pH values. A Chronometric spectrophotometric method is proposed to kinetically characterize the action of the PPO or POD on the basis of measuring the time it takes for a given amount of ascorbic acid to be consumed in the reaction with the o-quinone. The kinetic constants of mushroom PPO and horseradish POD are determined.
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Dawson,Nelson
, p. 245,246 (1938)
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Mentasti et al.
, p. 537,539-540 (1975)
Alzheimer's disease related copper(II)-β-amyloid peptide exhibits phenol monooxygenase and catechol oxidase activities
Da Silva, Giordano F. Z.,Ming, Li-June
, p. 5501 - 5504 (2005)
(Chemical Equation Presented) A gray area in gray matter: The Cu II complex of a truncated β-amyloid, CuAβ1-20, catalyzes the oxidation of catechol and the hydroxylation and oxidation of phenol (see picture) with dramatic rate accelerations (≈ 10 5-106-fold increases). The Cu-oxygen chemistry of CuAβ may offer both a better understanding of the chemical effect in the brains of patients who suffer from Alzheimer's disease as well as possible treatment strategies of this disease.
How well should the active site and the specific recognition be defined for proficient catalysis? - Effective and cooperative polyphenol/catechol oxidation and oxidative dna cleavage by a copper(II)-binding and H-bonding copolymer
Lykourinou, Vasiliki,Hanafy, Ahmed I.,Da Silva, Giordano F. Z.,Bisht, Kirpal S.,Larsen, Randy W.,Livingston, Brian T.,Angerhofer, Alexander,Ming, Li-June
, p. 2584 - 2592 (2008)
Despite the mainly inhomogeneous and unstructured nature of linear polymers, the CuII complex of a vinylpyridine-acrylamide copolymer exhibits very efficient 2-electron catalysis toward the oxidation of catechol and derivatives to form quinones with and without 80 mM (0.27%) H 2O2, showing remarkable (0.114-2.67) × 10 5 and (2.83-9.60) × 104-fold rate enhancements, respectively, in terms of first-order rate constant relative to auto-oxidation of the substrates in an aqueous environment under mild conditions. Metal-binding profiles suggest the presence of cooperativity in the catalysis. The oxidation catalysis is inhibited by the di-copper tyrosinase specific kojic acid. Moreover, electron paramagnetic resonance spectra reveal magnetic interaction of the CuII ions. On the basis of the results, the catalysis by this CuII-polymer seems to be consistent with the mechanism of type-3 di-copper oxidases. This complex also shows effective single- and double-stranded DNA cleavage in the presence of 1.0% H2O2. These studies suggest this CuII-polymer complex can serve as a unique chemical nuclease and a versatile chemical system for further exploration of Cu-oxygen chemistry. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Pyridinium Chlorochromate Supported on Montmorillonite–KSF as a Versatile Oxidant under Ball Milling Conditions
Hosseinzadeh, Rahman,Narimani, Erfan,Mavvaji, Mohammad
, p. 461 - 471 (2021/08/09)
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Dearomatization of Electron-Deficient Phenols to ortho-Quinones: Bidentate Nitrogen-Ligated Iodine(V) Reagents
Xiao, Xiao,Greenwood, Nathaniel S.,Wengryniuk, Sarah E.
supporting information, p. 16181 - 16187 (2019/11/05)
Despite their broad utility, the synthesis of ortho-quinones remains a significant challenge, in particular, access to electron-deficient derivatives remains an unsolved problem. Reported here is the first general method for the synthesis of electron-deficient ortho-quinones by direct oxidation of phenols. The reaction is enabled by a novel bidentate nitrogen-ligated iodine(V) reagent, a previously unexplored class of compounds which we have termed Bi(N)-HVIs. The reaction is extremely general and proceeds with excellent regioselectivity for the ortho over para isomer. Functionalization of the ortho-quinone products was examined, resulting in a facile one-pot synthesis of catechols, as well as the incorporation of a variety of heteroatom nucleophiles. This method represents the first synthetic application of Bi(N)-HVIs and demonstrates their potential as a platform for the further development of highly reactive, but also highly tunable, I(V) reagents.