Quinone benzoquinones. Medical search. Frequent questions

Quinones are oxidized derivatives of aromatic compounds and are often readily made from reactive aromatic compounds with electron-donating substituents such as phenols and catechols, which increase the nucleophilicity of the ring and contributes to the large redox potential needed to break aromaticity. (wikipedia.org)
1,2-Benzoquinone 1,4-Benzoquinone 1,4-Naphthoquinone 9,10-Anthraquinone The term quinone is also used more generally for a large class of compounds formally derived from aromatic quinones through replacement of some hydrogen atoms by other atoms or radicals. (wikipedia.org)
Quinones are well known as redox-active compounds. (rsc.org)
Thus, the concentrations of NADH, NAD, and quinone are varied separately and together to determine patterns of competition that are used to infer which compounds can occupy the active site simultaneously. (xray.cz)
It is a kind of Quinones compounds. (albtechnology.com)
The authors conclude that QR activity within the bone marrow may be a determinant of susceptibility of bone marrow derived stromal cells to the toxicity induced by redox active quinone compounds as evidenced by increased sensitivity of DBA/2 bone marrow stromal cells to HQ treatment and the protection against HQ toxicity in the QR induction studies. (cdc.gov)
Quinones are a group of compounds that are widely distributed in nature. (bocsci.com)
Quinones are a class of compounds that include quinones or are easily transformed into compounds with quinone-like properties, as well as compounds that are closely related to quinones in biosynthesis, and often exist in nature as pigments in animals, plants and microorganisms. (bocsci.com)
Quinone compounds have phenolic hydroxyl group, so they have certain acidity. (bocsci.com)
The acidity of quinone compounds varies significantly depending on the number and position of phenolic hydroxyl groups in the molecule. (bocsci.com)

The auto-oxidation of the neurotransmitter dopamine and its precursor L-Dopa generates the comparatively stable dopamine quinone which inhibits the functioning of dopamine transporter (DAT) and the TH enzyme and leads to low mitochondrial ATP production. (wikipedia.org)
Assays of WrbA NADH oxidation/quinone reduction activity were carried out. (xray.cz)
These reactions follow the decrease in NADH absorbance at 340 nm upon oxidation during reduction of ubiquinone-0 or benzoquinone. (xray.cz)
The main role of the enzyme called NfsA in Escherichia coli bacteria is thought to be to convert molecules called quinones into hydroquinones, which can protect the cell from toxic molecules produced in oxidation reactions. (elifesciences.org)
The adverse effects of HQ and its thioether metabolites are in part a consequence of their oxidation to the corresponding electrophilic 1,4-benzoquinones (BQ). (elsevierpure.com)
1,2-Benzoquinone is produced on oxidation of catechol exposed to air in aqueous solution or by ortho oxidation of a phenol . (alchetron.com)
The results indicate that the quinones derived from oxidation of 3,4-dihydroxybenzaldehyde, 3,4-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid participate in Michael addition reaction with triphenylphosphine ( 4 ). (ics-ir.org)
A quinone derivative (2,5-dimethyl-1,4-benzoquinone), a likely oxidation product of the transformation intermediate 2,5-dimethylphenol, is expected to be the most acutely and chronically toxic compound arsing from GFZ direct photolysis. (unito.it)

Quinones are electrophilic Michael acceptors stabilised by conjugation. (wikipedia.org)
Capture of Electrophilic Quinones in the Extracellular Space: Evidence for a Phase Zero Reaction. (bvsalud.org)
Electrophilic quinones are produced during the combustion of gasoline in the atmosphere . (bvsalud.org)
These results suggest that electrophilic quinones are readily trapped by CysSH released from A431 cells , forming less-toxic CysSH adducts and thereby repressing covalent modification of cellular proteins . (bvsalud.org)

Derivatives of the quinol and quinone with a hydroxylated t-butyl group were also formed. (aspetjournals.org)
The free anthraquinone and quinone derivatives are mostly sublimated. (bocsci.com)

Quinones are ubiquitous in biochemistry, where they typically function as electron carriers in processes such as photosynthesis and respiration. (gsu.edu)
We found that this quinone inhibited both mitochondrial respiration and photosynthesis in their electron transportation systems. (lookformedical.com)

Naphthoquinone has an odor similar to benzoquinone. (naturalremedies.org)
Here we employ density functional theory (DFT) based vibrational frequency calculations on benzoquinone (BQ) and naphthoquinone (NQ) model systems to help untangle the intrinsic and environmental factors that could shift the quinone's vibrational mode frequencies and intensities. (gsu.edu)
Quinones share a basic structural pattern: an o- or para-substituted diketone conjugated to an aromatic nucleus (benzoquinone) or a thickened polycyclic aromatic system, such as benzoquinone, naphthoquinone, phenanthrenequinone and anthraquinone. (bocsci.com)
Natural quinones are mostly colored crystals, benzoquinone and naphthoquinone exist mostly in free state, while anthraquinones are often combined into glycosides and exist in traditional Chinese medicine, most of them are difficult to get good crystallization. (bocsci.com)
Small molecules of benzoquinone and naphthoquinone are volatile and can be distilled with water vapor. (bocsci.com)

Ubiquinone-10 is a naturally occurring 1,4-benzoquinone involved in respiration apparatus. (wikipedia.org)
The quinone was found to have a mode of action against the ubiquinone reductase site from the results of different electron donor experiments on intact mitochondria from rat liver. (lookformedical.com)
Coenzyme Q10 (also known as ubiquinone, coenzyme Q, CoQ10) is a 1,4-benzoquinone, where Q refers to the quinone chemical group, and 10 refers to the number of isoprenyl subunits. (diff.org)
Professor R. A. Morton, in Great Britain, proposed the name ubiquinone, a melting together of the words ubiquitous and quinone, which was appropriate because the substance seems to appear nearly everywhere in cells and tissues. (q10facts.com)

When there is no phenolic hydroxyl group in the molecule, quinones are almost colorless, but with the introduction of phenolic hydroxyl group and other auxiliary chromophores, they have a certain color, and the more auxiliary chromophores introduced, the darker the color is, such as yellow, orange, brownish red and purple-red. (bocsci.com)
The Q10 molecule has a benzoquinone ring as its head and 10 isoprene repeats in its tail. (q10facts.com)

Pyrroloquinoline quinone is another biological redox cofactor. (wikipedia.org)
Comparison of the high-resolution E. coli WrbA structure with NQO1 implies significant differences in access to the enzyme active site by the cofactor and the NADH and quinone substrates. (xray.cz)

We selected the Escherichia coli nitro/quinone reductase NfsA for chloramphenicol detoxification by simultaneously randomising eight active-site residues and interrogating ~250,000,000 reconfigured variants. (elifesciences.org)
Differences in quinone reductase activity in primary bone marrow stromal cells derived from C57BL/6 and DBA/2 mice. (cdc.gov)

To handle these two issues, we have synthesized a novel organic cathode material by anchoring a quinone compound, 2,3-dicyano- p -benzoquinone (DCBQ) with a high redox potential of 3.37 V vs. Li/Li + , onto carbon nanotubes (CNTs) (CNTs-DCBQ) through a facile ''grafting to'' method. (osti.gov)

Ilanikashkouli, Mohammadnabi, "Calculated Vibrational Properties of Asymmetrically Hydrogen Bonded Benzoquinones and Naphthoquinones. (gsu.edu)
According to different chemical structures, quinones can be divided into benzoquinones, naphthoquinones, anthraquinones and phenanthrenequinones. (bocsci.com)

There was, however, no difference between the two strains of mice with regard to benzoquinone (583631) or phenol (108952) induced toxicity. (cdc.gov)
Phenol is further converted into hydroquinone, which is oxidized to benzoquinone. (cdc.gov)

In acidic conditions, quinone undergoes two-electron and two-proton reduction to hydroquinone. (wikipedia.org)
In alkaline conditions, quinones undergo a reversible single-step, two-electron reduction. (wikipedia.org)
In neutral conditions, quinones may undergo either a one-proton, two-electron reduction or a two-electron reduction. (wikipedia.org)
Specifically, we systematically study the effect that hydrogen bonds and quinone substituents have on the ��=�� mode vibrational frequencies of the neutral and one-electron reduced BQs and NQs. (gsu.edu)
Some of these quinones play the role of electron transfer in the redox reaction in living organisms, while some have antibacterial or antitumor activities, such as carob quinone, lanxuequinone, lapachone, etc. (bocsci.com)
The acidity of β-hydroxy quinones is stronger than that of α-hydroxy quinones because of the effect of electron absorption by carbonyl group, the electron cloud density of oxygen atom on β-hydroxy group is reduced and the dissociation degree of proton is increased. (bocsci.com)
The electron transport system, photosystem-II (PS-II), in chroloplast from spinach leaves was inhibited by the quinone in a similar way to that of the triazin sires herbicide, atrazin, with its mode of action against PS II. (lookformedical.com)

The endogenous biosynthesis of the quinone nucleus of coenzyme Q10 (CoQ10) from tyrosine is dependent on adequate vitamin B6 nutriture. (diff.org)

9,10-Anthraquinone-2,7-disulphonic acid (AQDS) a quinone similar to one found naturally in rhubarb has been used as a charge carrier in metal-free flow batteries. (wikipedia.org)

In both cases, improved chloramphenicol detoxification was only observed after an R225 substitution that largely eliminated activity with endogenous quinones. (elifesciences.org)

Para-Benzoquinone is an organic chemical compound commonly known as p-Quinone. (camlinfs.com)

Quinones are conjugated but not aromatic). (wikipedia.org)

Generally, the quinones containing carboxyl groups are more acidic. (bocsci.com)

A strain of the bacterium Pseudomonas mendocina metabolises benzoic acid , yielding 1,2-benzoquinone via catechol . (alchetron.com)

Dr. Crane used a technique called absorption spectroscopy to examine the yellow crystals, and he concluded that the mysterious crystals had to be quinones, which was puzzling because, up until that time, scientists assumed that only plants contained quinones (2). (q10facts.com)

Tyrosine and p -benzoquinone were the dominant metabolites in all of the secretions, accounting for approximately 11.29% of emissions, with the portion in the solid phase being generally higher than that in the liquid phase. (frontiersin.org)

This natural quinone has a long aliphatic chain (C17) including an unsaturated bond at its midpoint. (lookformedical.com)

Chloranil, a reagent in organic chemistry Lawsone, a dye present in the leaves of the henna plant Alizarin, a common red dye DDQ, a reagent in organic chemistry Daunorubicin, an anticancer drug Quinones form a polymers by formation of hydrogen bonding with ρ-hydroquinone. (wikipedia.org)

Mouse lung, however, produced more quinone relative to other metabolites than mouse liver. (aspetjournals.org)

The conjugates formed from hydroquinone (hydroquinone glucuronide and hydroquinone sulfate) are markers for this toxification pathway leading to benzoquinone. (cdc.gov)

This hypothesis was further demonstrated by the antimicrobial activity of p -benzoquinone. (frontiersin.org)

Quinones undergo addition reaction to form 1,4-addition products. (wikipedia.org)
An example of 1,4-addition reaction is the addition of hydrogen chloride to form chlorohydroquinone: Quinones can undergo Diels-Alder reactions. (wikipedia.org)
In this work, based on an EC mechanism, the observed homogeneous rate constants ( k obs ) of the reaction of produced benzoquinones with triphenylphosphine ( 4 ) were estimated by comparing the experimental cyclic voltammograms with the digitally simulated results. (ics-ir.org)

Conversely, the toxicity of paracetamol is due to its metabolism to a quinone imine, which then reacts with liver proteins to cause liver failure. (wikipedia.org)

Today, of course, we know that the quinones are biological substances with properties that are important for energy production in the human body. (q10facts.com)

Despite these structural differences our results clearly demonstrate the unusual two-plateau behaviour on the substrate concentration-dependence plots for NADH or benzoquinone as described for NQO1 by Hosada et al. (xray.cz)

A large scale industrial application of quinones is for the production of hydrogen peroxide. (wikipedia.org)
With FTIR DS it is possible to probe even small changes in hydrogen bonding between the quinones and nearby protein residues. (gsu.edu)

In this work bistriazole- p -benzoquinone was prepared and its electrochemical behaviour in aqueous alkaline solutions was studied by cyclic voltammetry. (rsc.org)

It is a yellow crystalline substance that is related to quinone, procurable by oxidizing naphthalene with chromic acid. (naturalremedies.org)

Quinones bound in protein complexes are often studied using Fourier-transform infrared (FTIR) difference spectroscopy (DS). (gsu.edu)
Although these reactive species covalently bind to protein -based nucleophiles in cells , resulting in the formation of protein adducts involved in the modulation of redox signaling pathways and cytotoxicity, the extracellular regulation of quinones is not understood. (bvsalud.org)

In Diels-Alder reactions quinones are used as dienophiles. (wikipedia.org)

Moreover, only p -benzoquinone was entirely significantly upregulated in the solid phase compared to the liquid phase. (frontiersin.org)

Numerous quinones are significant roles in biology. (wikipedia.org)

Depending on the quinone and the site of reduction, reduction can either rearomatise the compound or break the conjugation. (wikipedia.org)
In aprotic media, quinones undergo two-step reduction without protons. (wikipedia.org)

Therefore, metabolome analysis suggested that p -benzoquinone, which may potentially be developed to be a valuable marker for determining external immunity, was considered to be the main substance responsible for external immune functions. (frontiersin.org)
Dr. Folkers and his team confirmed that the substance was, in fact, a quinone, and the Merck team succeeded in identifying the chemical structure of the substance: trans 2,3, dimethoxy-5-methyl-6-decaprinyl-1,4-benzoquinone. (q10facts.com)

Para-Benzoquinone acts as a cross linking agent and is useful in stabilizing unsaturated polyester resins during processing, shipment, and storage in either catalyzed or per catalyzed form. (camlinfs.com)

Similar phenomena also occurred for other atmospheric quinones 1,4-NQ and 1,4-benzoquinone (1,4-BQ). (bvsalud.org)

K + . In order to know more about the chemical structure of the alkali salts, the lithium, sodium and potassium salts of bistriazole- p -benzoquinone were crystallized and their structure could be revealed by single crystal X-ray analysis. (rsc.org)

In the second step, the semiquinone is reduced into a quinone dianion. (wikipedia.org)
In a second step, quinone binds to the site vacated by NAD and is reduced by FADH2. (xray.cz)

The quinone acts as the dienophile and reacts with a diene at a carbon-carbon double bond. (wikipedia.org)

The natural quinone, hydroxydietrichequinone (3-heptadec-8-enyl-2-hydroxy-5-methoxy-[1,4]benzoquinone) is a secondary metabolite of Cyperus javanicus. (lookformedical.com)

The acidity of quinones without carboxyl groups increases with the number of phenolic hydroxyl groups, and when the number of phenolic hydroxyl groups is the same, the substitution position of phenolic hydroxyl groups has a greater influence on the acidity. (bocsci.com)

WrbA hereby bridges bacterial flavodoxins and eukaryotic NAD(P)H:quinone oxidoreductases with its three-dimensional structure clearly revealing a close relationship to mammalian NAD(P)H:quinone oxidoreductase, Nqo1 [1]. (xray.cz)

The inclusion of benzoquinone (BQ) equidistant between the TiO 2 and CdS through DNA assembly further increased H 2 production. (iucc.ac.il)
The inclusion of benzoquinone (BQ) equidistant between the TiO2 and CdS through DNA assembly further increased H2 production. (iucc.ac.il)

While the use of a second quinone in conjunction with BQ showed no more improvement, its location within the Z-scheme was found to strongly influence catalysis. (iucc.ac.il)

Anatomy1

Organisms6

Diseases1

Chemicals and Drugs54

Analytical, Diagnostic and Therapeutic Techniques and Equipment11

Phenomena and Processes19

Technology, Industry, Agriculture1

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Compounds10

Oxidation8

Electrophilic4

Derivatives2

Photosynthesis2

Naphthoquinone5

Ubiquinone4

Molecule2

Cofactor2

Reductase2

Redox potential1

Naphthoquinones2

Phenol2

Electron7

Biosynthesis1

Anthraquinone1

Endogenous1

Organic chemical1

Aromatic1

Acidic1

Catechol1

Crystals1

Tyrosine1

Aliphatic1

Anticancer1

Metabolites1

Hydroquinone1

Antimicrobial1

Reaction3

Metabolism1

Biological1

Differences1

Hydrogen2

Alkaline1

Crystalline1

Protein2

Reactions1

Significantly1

Roles1

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Similar1

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