Formation of superoxide ion via one-electron transfer from electron donors to singlet oxygen

Saito, Isao; Matsuura, Teruo; Inoue, Kenzo

doi:10.1021/ja00348a040

Cited by 144 publications

(83 citation statements)

References 9 publications

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“…With the recent confirmation that 02( 'Ag) is produced by stimulated PMNs (Steinbeck et al, 1992;and this work), the strong possibility that superoxide dismutation plays a role in the generation of this highly reactive oxidant, and the known reactivity of Oz('Ag) with aromatic amines (Saito et al, 1983), the question arose whether 0;-or the superoxide product, 02('Ag), was actually responsible for oxidizing DAB. Therefore, the present study evaluated the biochemical reactions of pure chemical sources of 02-and 0 2 ( ' Ag) with DAB, in the presence and absence of Mn**, and evaluated the formation of electron-dense DAB deposits in PMAstimulated PMNs under conditions that lead to the production of 02('Ag) or to a large amount of Oi-.…”

Section: Introductionmentioning

confidence: 64%

The DAB-Mn++ cytochemical method revisited: validation of specificity for superoxide.

Steinbeck¹,

Khan²,

Appel³

et al. 1993

J Histochem Cytochem.

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We wished to assess whether the previously developed 3,3-diaminobenzidine (DAB)-Mn" cytochemical method, purportedly specific for superoxide localization, is detecting superoxide 0;-and/or the superoxide product, Oz('Ag). We show here that polymorphonuclear leukocytes (PMNs) produce Oz(' Ag) extracellularly in response to non-phagocytic stimuli and that this production is inhibited by addition of superoxide dismutase, an enzyme typically used to demonstrate that a reaction is mediated by Oi-. Because Oz('Ag) is highly reactive and can be generated from Oi-, the reactivity of a pure chemical source of Oz('Ag) with the cytochemical probe DAB was examined in the presence and absence of Mn**. Reactions between DAB and Oz('Ag), thermally released from 1,4-dimethyl-napthalene-1,4-endoperoxide (DNE), indicated that Oz('Ag) directly reacted with DAB, forming an insoluble DAB polymer, and that this reaction was increased by the presence of Mn++. The direct reaction of Oz('Ag) with DAB was confirmed using near-IR emission spectroscopy. The near-IR emission spectrum of DNE as it was warmed showed the characteristic energy emission peak of OZ('Ag) and the intensity of this peak was reduced by the addition of DAB;

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Section: Introductionmentioning

confidence: 64%

The DAB-Mn++ cytochemical method revisited: validation of specificity for superoxide.

Steinbeck¹,

Khan²,

Appel³

et al. 1993

J Histochem Cytochem.

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“…mally from hydrogen peroxide (28,29) in the peroxide bleaching, or photochemically from singlet oxygen (30)(31)(32)(33) in the course of photoyellowing of pulp. Assuming that substituent effects in the catechol derivatives are similar to those in the hydroquinone derivatives, i.e., that the electron-rich substituents make both reduction potential of catechol radical and oxidation potential of quinone more negative, it may be concluded that all lignin-derived o-quinones (such as 3-methoxy-l,2-benzoquinone) are expected to be rapidly oxidized by the superoxide radical (see Table 1).…”

Section: Redox Potential Of Catechoyquinone Redox Pairmentioning

confidence: 99%

Redox reactions of 3,5-di-tert-butyl-1,2-benzoquinone. Implications for reversal of paper yellowing

Jovanović¹,

Kónya²,

Scaiano³

1995

Can. J. Chem.

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One-and two-electron transfer reactions of 3,5-di-tert-butylcatechol and the corresponding quinone were studied by fast kinetic spectroscopy coupled with laser photolysis and pulse radiolysis, and by cyclic voltammetry in aqueous solutions. Photoionization of catechol yields the same semiquinone radical as the formate-radical-induced quinone reduction in the pulse radiolysis experiment. The neutral semiquinone radical deprotonates at pK, = 6.0 2 0. I, as deduced from the pH induced changes in the radical spectra. The twoelectron reduction potentials of quinone and catechol were measured by cyclic voltammetry in aqueous solutions containing 25% methanol in the pH range 3-14. The pH dependence has two linear parts with slopes of 0.056 and 0.03 VIpH, intersecting at pK, = 10.0. This is in excellent agreement with pKa = 10.05 ? 0.05 obtained spectrophotometrically. The reduction potential of 3,5-di-tert-butyl quinone, E7 = 0.01 ? 0.04 V, was obtained from the one-electron transfer equilibrium of the quinone with the oxygen/superoxide redox couple by pulse radiolysis. The rate constant of the reaction of quinone with the superoxide radical, k = 1.2 x lo9 M-I sK', is higher than those of the superoxide reduction by catechols and phenols (typically -lo5 MK1 s-I); thus, lignin o-quinones could be efficient scavengers of superoxide under the conditions relevant for the photo-induced yellowing of lignin-rich paper. The reaction with 0; effectively bleaches yellow quinone and generates metastable furanone, which hydrolyses to muconic acid, thus completely eliminating yellow quinone. 3,5-Ditert-butylquinone also undergoes rapid bleaching with ascorbate, k = 600 2 100 M-I S-I, in methanol. The reaction has a 1:l stoichiometry and leads to complete reduction of quinone to catechol with concomitant oxidation of ascorbate to dehydroascorbate. This unusual selectivity and the fact that the reaction of the milder oxidant 3,5-di-tert-butylquinone is an order of magnitude faster than that of stronger oxidantp-benzoquinone (k = 60 2 10 M-' s-') suggest that a nucleophilic attack of quinone at the ascorbate double bond initiates the reaction.Key words: superoxide, lignin, photochemistry, quinone.RCsumC : Faisant appel A voltampCromCtrie cyclique et h la spectroscopie cinktique rapide couplee A photolyse laser et A la radiolyse pulsCe, on a CtudiC les rkactions de transfert d'un et de deux Clectrons du 3,5-di-tertbutylcatCcho1 et la quinone correspondante, en solutions aqueses. La photoionisation du catCchol fournit le meme radical semiquinone que celui produit lors de la rCduction radicalaire de la quinone induite par le formiate dans 17expCrience de radiolyse pulsCe. Sur la base des changements induits de pH dans le spectre radicalaire, le radical semiquinone neutre se diprotone h un pK, = 6,O 2 0,l. On a utilisC la voltampCromCtrie cyclique pour mesurer les potentiels de rCduction h deux electrons quinonelcatCcho1 en solutions aqueuses contenant 25% de mtthanol, A des pH allant de 3 A 14. La relation avec le pH prCsente d...

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“…Synthesis of amino-substituted 1-aryl-1,3-butadiones. [8] 0.52 (0.32) [8] 0.36 (0.16) [9] 0.23 (À0.04) [9] À0.09 c a Potentials were determined by cyclic voltammetry in 0.1 M NBu 4 PF 6 CH 3 CN solution vs Fc/Fc þ at 298 K with a scan rate of 0.1 V/s. b E p,a ¼ anodic peak potential; the oxidation is irreversible under the experimental conditions.…”

Section: Signalsmentioning

confidence: 99%

Synthesis of Aryl-Substituted 1,3-Butadiones

König

2003

Synthetic Communications

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Formation of superoxide ion via one-electron transfer from electron donors to singlet oxygen

Cited by 144 publications

References 9 publications

The DAB-Mn++ cytochemical method revisited: validation of specificity for superoxide.

The DAB-Mn++ cytochemical method revisited: validation of specificity for superoxide.

Redox reactions of 3,5-di-tert-butyl-1,2-benzoquinone. Implications for reversal of paper yellowing

Synthesis of Aryl-Substituted 1,3-Butadiones

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