The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Chemical Compound Review

o-Quinone     cyclohexa-2,4-diene-1,6-dione

Synonyms: o-Benzoquinone, CPD-385, SureCN113494, AG-G-06448, CHEBI:17253, ...
Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of C02351

  • These results confirm that addition occurs in oxidizing polyhydroxy aromatic systems, probably via o-quinone, in a reaction considered to account for much of the toxicity found for catechols and catecholamines [1].
  • The implications of the o-quinone/QM pathway to the in vivo effects of catechol estrogens are not known; however, given the direct link between excessive exposure to endogenous estrogens and the enhanced risk of breast cancer, the potential for formation of additional reactive intermediates needs to be explored [2].
  • Formation of ortho-benzoquinone from sodium benzoate by Pseudomonas mendocina P2d [3].

High impact information on C02351

  • The coexistence of N-acetylcysteine in the in vitro oxidation of 3,4-AH-BAL by GriF resulted in the formation of grixazone A, suggesting that the -SH group of N-acetylcysteine is conjugated to the o-quinone imine formed from 3,4-AHBAL and that the conjugate is presumably coupled with another molecule of the o-quinone imine [4].
  • Oxidation of the trans-1,2-dihydrodiol of naphthalene or the 7,8-dihydrodiol of benzo[a]pyrene by the homogeneous rat liver dehydrogenase in 50 mM glycine at pH 9.0 led to the formation of multiple products by TLC, none of which co-migrated with the corresponding o-quinone standards [5].
  • This study represents the first chemical demonstration of a true o-quinone hydration, which occurs in cofactor biogenesis in copper amine oxidases [6].
  • The reaction is believed to proceed via a mechanism involving water-mediated formal excited state intramolecular proton transfer (ESIPT) from the phenolic OH to the 10-position of the anthracene ring, generating an o-quinone methide intermediate that is observable by nanosecond laser flash photolysis, and is trappable with nucleophiles [7].
  • In association with browning, leaf proteins remain undegraded during ensiling, presumably due to PPO-generated o-quinone inhibition of leaf proteases [8].

Chemical compound and disease context of C02351

  • These results substantiate the conclusion that the involvement of quinoids in catechol estrogen toxicity depends on a combination of the rate of formation of the o-quinone, the lifetime of the o-quinone, and the electrophilic/redox reactivity of the quinoids [9].

Biological context of C02351

  • The results are indicative of the intracellular metabolic activation of quercetin to o-quinone, the process which can be partially associated with the observed concentration-dependent cytotoxic effect of quercetin [10].
  • We have found that stypoldione, a bright red o-quinone isolated from the brown alga Stypopodium zonale, inhibits the division of sea urchin embryos in a concentration-dependent manner (IC50 approximately 2.5 X 10(-6) M) [11].
  • Stypoldione, a marine natural product that possesses an o-quinone functional group, has been shown to inhibit a variety of biological processes including cell division [12].
  • This difference originates from the regiospecific hydroxylation (ortho position) and subsequent oxidation of the intermediate o-aminophenol to the corresponding o-quinone imine [13].
  • These results suggest that the reactions of benzofuroxan with both actinidin and papain involve rate-determining attack of the catalytic-site thiol group to produce an intermediate adduct that then reacts rapidly with water to form enzyme sulphenic acid and o-benzoquinone dioxime [14].

Anatomical context of C02351

  • Using a well-defined model system, junctional SR vesicles from skeletal muscle, we show that a single o-quinone metabolite of B[a]P, B[a]P-7,8-dione, can account for altered Ca(2+) transport across microsomal membranes [15].
  • These results suggest that in melanocytes these phenols are oxidised by tyrosinase to the corresponding o-quinone forms, some of which conjugate with sulphydryl enzymes through cysteine residues, thus exerting cytotoxic effects [16].
  • Like endogenous estrogens, 8,9-dehydroestrone was primarily converted by rat liver microsomes to the 2-hydroxylated rather than the 4-hydroxylated o-quinone GSH conjugates; the ratio of 2-hydroxy-8,9-dehydroestrone versus 4-hydroxy-8,9-dehydroestrone was 6:1 [17].
  • Several new prenylnaphthohydroquinone derivatives have been prepared through the Diels-Alder condensation between alpha-myrcene and 1,2-benzoquinone and evaluated for their cytotoxic activity against A-549, HT-29 and MB-231 cultured cell lines [18].
  • The inhibition of alpha-KGDH is dependent on the oxidation of DHBT-1, catalyzed by an unknown constituent of the inner mitochondrial membrane, to an electrophilic o-quinone imine that covalently modifies active site sulfhydryl residues [19].

Associations of C02351 with other chemical compounds

  • The o-quinone derived from CAF was rather unstable and decomposed during its isolation [20].
  • Phenol is oxidized in the sensor membrane by the oxygen-consuming tyrosinase via catechol to o-quinone [21].
  • Monophenolase activity of PPO catalyses the oxidation of phenol to o-quinone (step C). o-Quinone can then enter an amplification recycling process involving electrochemical reduction (step E) and enzymatic reoxidation (step C': catecholase activity) [22].
  • Pulse-radiolysis experiments, in which the o-quinone is formed by disproportionation of semiquinone radicals generated by single-electron oxidation of DBC, showed that the quinomethane (A480 6440 is formed through the intermediacy of the o-quinone with a rate constant at neutral pH of 7.5 s-1 [23].
  • Strand scission was extensive, dependent on the concentration of o-quinone (0-10 microM), and required the presence of NADPH (1 mM) and CuCl2 (10 microM) [24].

Gene context of C02351

  • The Michaelis constant of tyrosinase for oxygen in the presence of monophenols and o-diphenols, which generate a cyclizable o-quinone, has been studied [25].
  • Only one QM was observed from the o-quinone of 4-hydroxyestrone, 4-OHE-QM2 (4-hydroxy-1(2),4(5),9(10)- oestratrien-3,17-dione) which is analogous to the C ring analog (2-OHE-QM2) from the o-quinone of 2-hydroxyestrone [26].
  • Benzofuroxan reacts with the catalytic-site thiol group of cathepsin B (EC to produce stoichiometric amount of the chromophoric reduction product, o-benzoquinone dioxime [27].
  • In this mechanism, the electron donor (NADPH) and acceptor (o-quinone) are bound in close proximity, which permits hydride transfer without formal protonation of the acceptor carbonyl by Tyr 55 [28].
  • Although 3,4-EQ was not an apparent substrate for the two-electron reduction catalyzed by DT D, this o-quinone was a substrate for the one-electron reduction catalyzed by cytochrome P450 reductase [29].

Analytical, diagnostic and therapeutic context of C02351

  • Synthesis and liquid chromatography/tandem mass spectrometric characterization of the adducts of bisphenol A o-quinone with glutathione and nucleotide monophosphates [30].
  • Using HPLC and mass spectrometry, one of the metabolites was shown to be the reactive o-quinone derivative of the parent drug which resulted from the peroxidative O-demethylation [31].
  • Phenol generated by the action of ALP is monitored at the tyrosinase composite electrode through the electrochemical reduction of the o-quinone produced to catechol, which produces a cycle between the tyrosinase substrate and the electroactive product, giving rise to the amplification of the biosensor response and to the sensitive detection of ALP [32].
  • The reaction product was identified by cochromatography, fluorimetry and mass spectroscopy as BA-3,4-catechol, but interconversions between the catechol and the corresponding o-quinone during the analytical procedures were detected [33].
  • The o-quinone was isolated from incubates and identified by its FTIR spectrum, in particular, by the appearance of a new band at 1652 cm-1, its migration in HPLC systems, its ultraviolet spectrum, its derivatization with phenylenediamine and comparison of these properties with the periodate oxidation product of the same substrate [34].


  1. Semiquinone anion radicals from addition of amino acids, peptides, and proteins to quinones derived from oxidation of catechols and catecholamines. An ESR spin stabilization study. Kalyanaraman, B., Premovic, P.I., Sealy, R.C. J. Biol. Chem. (1987) [Pubmed]
  2. Bioactivation of estrone and its catechol metabolites to quinoid-glutathione conjugates in rat liver microsomes. Iverson, S.L., Shen, L., Anlar, N., Bolton, J.L. Chem. Res. Toxicol. (1996) [Pubmed]
  3. Formation of ortho-benzoquinone from sodium benzoate by Pseudomonas mendocina P2d. Parulekar, C., Mavinkurve, S. Indian J. Exp. Biol. (2006) [Pubmed]
  4. A novel o-aminophenol oxidase responsible for formation of the phenoxazinone chromophore of grixazone. Suzuki, H., Furusho, Y., Higashi, T., Ohnishi, Y., Horinouchi, S. J. Biol. Chem. (2006) [Pubmed]
  5. Spectroscopic identification of ortho-quinones as the products of polycyclic aromatic trans-dihydrodiol oxidation catalyzed by dihydrodiol dehydrogenase. A potential route of proximate carcinogen metabolism. Smithgall, T.E., Harvey, R.G., Penning, T.M. J. Biol. Chem. (1988) [Pubmed]
  6. A dopaquinone model that mimics the water addition step of cofactor biogenesis in copper amine oxidases. Ling, K.Q., Sayre, L.M. J. Am. Chem. Soc. (2005) [Pubmed]
  7. Photoaddition of water and alcohols to the anthracene moiety of 9-(2'-hydroxyphenyl)anthracene via formal excited state intramolecular proton transfer. Flegel, M., Lukeman, M., Huck, L., Wan, P. J. Am. Chem. Soc. (2004) [Pubmed]
  8. Cloning and characterization of red clover polyphenol oxidase cDNAs and expression of active protein in Escherichia coli and transgenic alfalfa. Sullivan, M.L., Hatfield, R.D., Thoma, S.L., Samac, D.A. Plant Physiol. (2004) [Pubmed]
  9. Bioreductive activation of catechol estrogen-ortho-quinones: aromatization of the B ring in 4-hydroxyequilenin markedly alters quinoid formation and reactivity. Shen, L., Pisha, E., Huang, Z., Pezzuto, J.M., Krol, E., Alam, Z., van Breemen, R.B., Bolton, J.L. Carcinogenesis (1997) [Pubmed]
  10. Quercetin may act as a cytotoxic prooxidant after its metabolic activation to semiquinone and quinoidal product. Metodiewa, D., Jaiswal, A.K., Cenas, N., Dickancaité, E., Segura-Aguilar, J. Free Radic. Biol. Med. (1999) [Pubmed]
  11. Effect of stypoldione on cell cycle progression, DNA and protein synthesis, and cell division in cultured sea urchin embryos. White, S.J., Jacobs, R.S. Mol. Pharmacol. (1983) [Pubmed]
  12. Mechanism of action of the marine natural product stypoldione: evidence for reaction with sulfhydryl groups. O'Brien, E.T., Asai, D.J., Groweiss, A., Lipshutz, B.H., Fenical, W., Jacobs, R.S., Wilson, L. J. Med. Chem. (1986) [Pubmed]
  13. Catalytic oxidation of 2-aminophenols and ortho hydroxylation of aromatic amines by tyrosinase. Toussaint, O., Lerch, K. Biochemistry (1987) [Pubmed]
  14. Investigation of the catalytic site of actinidin by using benzofuroxan as a reactivity probe with selectivity for the thiolate-imidazolium ion-pair systems of cysteine proteinases. Evidence that the reaction of the ion-pair of actinidin (pKI 3.0, pKII 9.6) is modulated by the state of ionization of a group associated with a molecular pKa of 5.5. Salih, E., Brocklehurst, K. Biochem. J. (1983) [Pubmed]
  15. A bioactive metabolite of benzo[a]pyrene, benzo[a]pyrene-7,8-dione, selectively alters microsomal Ca2+ transport and ryanodine receptor function. Pessah, I.N., Beltzner, C., Burchiel, S.W., Sridhar, G., Penning, T., Feng, W. Mol. Pharmacol. (2001) [Pubmed]
  16. Mechanism of selective toxicity of 4-S-cysteinylphenol and 4-S-cysteaminylphenol to melanocytes. Ito, S., Kato, T., Ishikawa, K., Kasuga, T., Jimbow, K. Biochem. Pharmacol. (1987) [Pubmed]
  17. Synthesis and reactivity of the catechol metabolites from the equine estrogen, 8,9-dehydroestrone. Zhang, F., Yao, D., Hua, Y., van Breemen, R.B., Bolton, J.L. Chem. Res. Toxicol. (2001) [Pubmed]
  18. New cytotoxic-antineoplastic prenyl-1,2-naphthohydroquinone derivatives. Molinari, A., Oliva, A., Ojeda, C., Miguel del Corral, J.M., Castro, M.A., Cuevas, C., San Feliciano, A. Bioorg. Med. Chem. (2005) [Pubmed]
  19. Oxidative metabolites of 5-S-cysteinyldopamine inhibit the alpha-ketoglutarate dehydrogenase complex: possible relevance to the pathogenesis of Parkinson's disease. Shen, X.M., Li, H., Dryhurst, G. Journal of neural transmission (Vienna, Austria : 1996) (2000) [Pubmed]
  20. Nitric oxide promotes strong cytotoxicity of phenolic compounds against Escherichia coli: the influence of antioxidant defenses. Urios, A., López-Gresa, M.P., González, M.C., Primo, J., Martínez, A., Herrera, G., Escudero, J.C., O'Connor, J.E., Blanco, M. Free Radic. Biol. Med. (2003) [Pubmed]
  21. Zeptomole-detecting biosensor for alkaline phosphatase in an electrochemical immunoassay for 2,4-dichlorophenoxyacetic acid. Bauer, C.G., Eremenko, A.V., Ehrentreich-Förster, E., Bier, F.F., Makower, A., Halsall, H.B., Heineman, W.R., Scheller, F.W. Anal. Chem. (1996) [Pubmed]
  22. Amplification of amperometric biosensor responses by electrochemical substrate recycling. 3. Theoretical and experimental study of the phenol-polyphenol oxidase system immobilized in Laponite hydrogels and layer-by-layer self-assembled structures. Coche-Guerente, L., Labbé, P., Mengeaud, V. Anal. Chem. (2001) [Pubmed]
  23. Tyrosinase kinetics: failure of the auto-activation mechanism of monohydric phenol oxidation by rapid formation of a quinomethane intermediate. Cooksey, C.J., Garratt, P.J., Land, E.J., Ramsden, C.A., Riley, P.A. Biochem. J. (1998) [Pubmed]
  24. DNA strand scission by polycyclic aromatic hydrocarbon o-quinones: role of reactive oxygen species, Cu(II)/Cu(I) redox cycling, and o-semiquinone anion radicals,. Flowers, L., Ohnishi, S.T., Penning, T.M. Biochemistry (1997) [Pubmed]
  25. Oxygen Michaelis constants for tyrosinase. Rodríguez-López, J.N., Ros, J.R., Varón, R., García-Cánovas, F. Biochem. J. (1993) [Pubmed]
  26. p-Quinone methides are the major decomposition products of catechol estrogen o-quinones. Bolton, J.L., Shen, L. Carcinogenesis (1996) [Pubmed]
  27. Chemical evidence for the pH-dependent control of ion-pair geometry in cathepsin B. Benzofuroxan as a reactivity probe sensitive to differences in the mutual disposition of the thiolate and imidazolium components of cysteine proteinase catalytic sites. Willenbrock, F., Brocklehurst, K. Biochem. J. (1986) [Pubmed]
  28. Retention of NADPH-linked quinone reductase activity in an aldo-keto reductase following mutation of the catalytic tyrosine. Schlegel, B.P., Ratnam, K., Penning, T.M. Biochemistry (1998) [Pubmed]
  29. Cellular biochemical determinants modulating the metabolism of estrone 3,4-quinone. Nutter, L.M., Zhou, B., Sierra, E.E., Wu, Y.Y., Rummel, M.M., Gutierrez, P., Abul-Hajj, Y. Chem. Res. Toxicol. (1994) [Pubmed]
  30. Synthesis and liquid chromatography/tandem mass spectrometric characterization of the adducts of bisphenol A o-quinone with glutathione and nucleotide monophosphates. Qiu, S.X., Yang, R.Z., Gross, M.L. Chem. Res. Toxicol. (2004) [Pubmed]
  31. Peroxidative free radical formation and O-demethylation of etoposide(VP-16) and teniposide(VM-26). Haim, N., Roman, J., Nemec, J., Sinha, B.K. Biochem. Biophys. Res. Commun. (1986) [Pubmed]
  32. Rapid and highly sensitive electrochemical determination of alkaline phosphatase using a composite tyrosinase biosensor. Serra, B., Morales, M.D., Reviejo, A.J., Hall, E.H., Pingarrón, J.M. Anal. Biochem. (2005) [Pubmed]
  33. The oxidation of the highly tumorigenic benz[a]anthracene 3,4-dihydrodiol by rat liver dihydrodiol dehydrogenase. Klein, J., Post, K., Thomas, H., Wörner, W., Setiabudi, F., Frank, H., Oesch, F., Platt, K.L. Chem. Biol. Interact. (1990) [Pubmed]
  34. Isolation of estradiol-2,3-quinone and its intermediary role in melanin formation. Jacobsohn, M.K., Byler, D.M., Jacobsohn, G.M. Biochim. Biophys. Acta (1991) [Pubmed]
WikiGenes - Universities