Tmic
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Record Information
Version2.0
Creation Date2014-09-05 17:10:15 UTC
Update Date2014-12-24 20:26:52 UTC
Accession NumberT3D4577
Identification
Common NameHydroquinone
ClassSmall Molecule
DescriptionHydroquinone, also benzene-1,4-diol, is an aromatic organic compound which is a type of phenol. Hydroquinone is commonly used as a biomarker for benzene exposure. The presence of hydroquinone in normal individuals stems mainly from direct dietary ingestion, catabolism of tyrosine and other substrates by gut bacteria, ingestion of arbutin containing foods, cigarette smoking, and the use of some over-the-counter medicines. In human medicine, hydroquinone is used as a topical application in skin whitening to reduce the color of skin. In 2006, the United States Food and Drug Administration revoked its previous approval of hydroquinone and proposed a ban on all over-the-counter preparations. The FDA stated that hydroquinone cannot be ruled out as a potential carcinogen. This conclusion was reached based on the extent of absorption in humans and the incidence of neoplasms in rats in several studies where adult rats were found to have increased rates of tumours, including thyroid follicular cell hyperplasias, anisokaryosis, mononuclear cell leukemia, hepatocellular adenomas and renal tubule cell adenomas. Numerous studies have revealed that hydroquinone can cause exogenous ochronosis, a disfiguring disease in which blue-black pigments are deposited onto the skin, if taken orally; however, skin preparations containing the ingredient are administered topically. The FDA has classified hydroquinone currently as a safe product, as currently used. (Wikipedia)
Compound Type
  • Cigarette Toxin
  • Food Toxin
  • Household Toxin
  • Metabolite
  • Organic Compound
  • Pollutant
  • Synthetic Compound
Chemical Structure
Thumb
Synonyms
Synonym
1,4-Benzenediol
1,4-Dihydroxy-benzeen
1,4-Dihydroxy-benzol
1,4-Dihydroxybenzen
1,4-Diidrobenzene
4-Hydroxyphenol
a-Hydroquinone
alpha-Hydroquinone
b-Quinol
Benzene-1,4-diol
Benzohydroquinone
Benzoquinol
beta-Quinol
Dihydroquinone
Dihydroxybenzene
Hydrochinon
Hydrochinone
Hydroquinol
Hydroquinole
Hydroquinone for synthesis
Hydroquinone gr
Hydroquinoue
Idrochinone
Melanex
p-Benzenediol
p-Dihydroxybenzene
p-Dioxobenzene
p-Dioxybenzene
p-Hydroquinone
p-Hydroxybenzene
p-Hydroxyphenol
Phiaquin
Quinol
Solaquin forte
Chemical FormulaC6H6O2
Average Molecular Mass110.111 g/mol
Monoisotopic Mass110.037 g/mol
CAS Registry Number123-31-9
IUPAC Namebenzene-1,4-diol
Traditional Nameα-hydroquinone
SMILESOC1=CC=C(O)C=C1
InChI IdentifierInChI=1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H
InChI KeyInChIKey=QIGBRXMKCJKVMJ-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as hydroquinones. Hydroquinones are compounds containing a hydroquinone moiety, which consists of a benzene ring with a hydroxyl groups at positions 1 and 4.
KingdomOrganic compounds
Super ClassBenzenoids
ClassPhenols
Sub ClassBenzenediols
Direct ParentHydroquinones
Alternative Parents
Substituents
  • Hydroquinone
  • 1-hydroxy-2-unsubstituted benzenoid
  • Monocyclic benzene moiety
  • Organic oxygen compound
  • Hydrocarbon derivative
  • Organooxygen compound
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Cytoplasm
  • Extracellular
Biofluid LocationsNot Available
Tissue Locations
  • Bone Marrow
  • Fibroblasts
  • Kidney
  • Liver
  • Skin
  • Stratum Corneum
PathwaysNot Available
ApplicationsNot Available
Biological Roles
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceHydroquinone is a white granular solid at room temperature and pressure.
Experimental Properties
PropertyValue
Melting Point172.3 °C
Boiling Point286°C (546.8°F)
Solubility72.0 mg/mL at 25 °C
LogP0.59
Predicted Properties
PropertyValueSource
Water Solubility95.5 g/LALOGPS
logP0.71ALOGPS
logP1.37ChemAxon
logS-0.06ALOGPS
pKa (Strongest Acidic)9.68ChemAxon
pKa (Strongest Basic)-5.9ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area40.46 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity30.02 m³·mol⁻¹ChemAxon
Polarizability10.75 ųChemAxon
Number of Rings1ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-MS (2 TMS)splash10-0f79-2490000000-6b4fec222a3499d93790View in MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-03di-9800000000-c90fd4986fea9691ecbfView in MoNA
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-03e9-9300000000-f8b11742557329691e8aView in MoNA
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-0f79-2490000000-6b4fec222a3499d93790View in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0f79-2690000000-7306adcc7121a11d67ccView in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-03di-5900000000-954dc96d8e3eb85b8324View in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-00e9-8950000000-512c0cf5ddc0b120ec8eView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-03di-9600000000-e670ba090cb27367db12View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-01p6-9000000000-5fc32c7688c1612df1e7View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-000i-9000000000-c5853ce8ef225ea5c353View in MoNA
LC-MS/MSLC-MS/MS Spectrum - EI-B (Unknown) , Positivesplash10-03di-9800000000-c90fd4986fea9691ecbfView in MoNA
LC-MS/MSLC-MS/MS Spectrum - , negativesplash10-0a4i-0900000000-5635f0157cd37deb1121View in MoNA
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-03di-2900000000-05be113033a709130eedView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-03di-0900000000-8d8328e4f7cd2ebaa27dView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-03di-1900000000-9290fcb93f170fc3143fView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-01si-9200000000-9f707b9d0c4ad0b73b30View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0a4i-0900000000-d3aae38632ac4c40fd4fView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0a4i-0900000000-74f15490ba4f49cf8c18View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a4i-9800000000-1cb01248e88fce387578View in MoNA
MSMass Spectrum (Electron Ionization)splash10-03di-9500000000-1fa8477944a662535e76View in MoNA
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
1D NMR13C NMR SpectrumNot AvailableView in JSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableView in JSpectraViewer
Toxicity Profile
Route of ExposureNot Available
Mechanism of ToxicityNot Available
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)3, not classifiable as to its carcinogenicity to humans. (16)
Uses/SourcesHydroquinone has a variety of uses principally associated with its action as a reducing agent which is soluble in water. It is a major component in most photographic developers where, with the compound Metol, it reduces silver halides to elemental silver. In human medicine, hydroquinone is used as a topical application in skin whitening to reduce the color of skin.
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDHMDB02434
PubChem Compound ID785
ChEMBL IDCHEMBL537
ChemSpider ID764
KEGG IDC00530
UniProt IDNot Available
OMIM ID
ChEBI ID17594
BioCyc ID236-TRICHLOROHYDROQUINONE
CTD IDNot Available
Stitch IDNot Available
PDB IDHQE
ACToR IDNot Available
Wikipedia LinkHydroquinone
References
Synthesis ReferenceMiyanohara, Isao; Yanagihara, Tadahisa. Hydroquinone. Jpn. Kokai Tokkyo Koho (1977), 4 pp.
MSDSLink
General References
  1. Gaskell M, McLuckie KI, Farmer PB: Comparison of the repair of DNA damage induced by the benzene metabolites hydroquinone and p-benzoquinone: a role for hydroquinone in benzene genotoxicity. Carcinogenesis. 2005 Mar;26(3):673-80. Epub 2004 Dec 23. [15618234 ]
  2. McDonald TA, Holland NT, Skibola C, Duramad P, Smith MT: Hypothesis: phenol and hydroquinone derived mainly from diet and gastrointestinal flora activity are causal factors in leukemia. Leukemia. 2001 Jan;15(1):10-20. [11243376 ]
  3. Inayat-Hussain SH, McGuinness SM, Johansson R, Lundstrom J, Ross D: Caspase-dependent and -independent mechanisms in apoptosis induced by hydroquinone and catechol metabolites of remoxipride in HL-60 cells. Chem Biol Interact. 2000 Aug 15;128(1):51-63. [10996300 ]
  4. Carbonnelle P, Lison D, Leroy JY, Lauwerys R: Effect of the benzene metabolite, hydroquinone, on interleukin-1 secretion by human monocytes in vitro. Toxicol Appl Pharmacol. 1995 Jun;132(2):220-6. [7540334 ]
  5. Keh ES, Hayakawa I, Takahashi H, Watanabe A, Iwasaki Y, Akiyoshi K, Nakabayashi N: Improving a self-curing dental resin by eliminating oxygen, hydroquinone and water from its curing process. Dent Mater J. 2002 Dec;21(4):373-82. [12608426 ]
  6. Subrahmanyam VV, Kolachana P, Smith MT: Hydroxylation of phenol to hydroquinone catalyzed by a human myeloperoxidase-superoxide complex: possible implications in benzene-induced myelotoxicity. Free Radic Res Commun. 1991;15(5):285-96. [1666626 ]
  7. Li X, Zhuang Z, Liu J, Huang H, Wei Q, Yang X: [Protein changes in human embryonic lung fibroblasts after hydroquinone stimulation using proteomic technique]. Wei Sheng Yan Jiu. 2004 Nov;33(6):654-7. [15727168 ]
  8. Bucks DA, McMaster JR, Guy RH, Maibach HI: Percutaneous absorption of hydroquinone in humans: effect of 1-dodecylazacycloheptan-2-one (azone) and the 2-ethylhexyl ester of 4-(dimethylamino)benzoic acid (Escalol 507). J Toxicol Environ Health. 1988;24(3):279-89. [3260963 ]
  9. Barber ED, Hill T, Schum DB: The percutaneous absorption of hydroquinone (HQ) through rat and human skin in vitro. Toxicol Lett. 1995 Oct;80(1-3):167-72. [7482585 ]
  10. Boyle J, Kennedy CT: Hydroquinone concentrations in skin lightening creams. Br J Dermatol. 1986 Apr;114(4):501-4. [3964548 ]
  11. Nilsson LB: High sensitivity determination of the remoxipride hydroquinone metabolite NCQ-344 in plasma by coupled column reversed-phase liquid chromatography and electrochemical detection. Biomed Chromatogr. 1998 Mar-Apr;12(2):65-8. [9568272 ]
  12. Oliveira NL, Kalf GF: Induced differentiation of HL-60 promyelocytic leukemia cells to monocyte/macrophages is inhibited by hydroquinone, a hematotoxic metabolite of benzene. Blood. 1992 Feb 1;79(3):627-33. [1732008 ]
  13. Wester RC, Melendres J, Hui X, Cox R, Serranzana S, Zhai H, Quan D, Maibach HI: Human in vivo and in vitro hydroquinone topical bioavailability, metabolism, and disposition. J Toxicol Environ Health A. 1998 Jun 26;54(4):301-17. [9638901 ]
  14. Kooyers TJ, Westerhof W: [Toxicological aspects and health risks associated with hydroquinone in skin bleaching formula]. Ned Tijdschr Geneeskd. 2004 Apr 17;148(16):768-71. [15129564 ]
  15. Halliwell, Barry B., and Henrik E. Poulsen (2006). Cigarette Smoke and Oxidative Stress. Berlin: Springer. [ISBN: 978-3-540-31410-3 (Print) 978-3-540-32232-0 (Online)]
  16. International Agency for Research on Cancer (2014). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide. Can hydrates cyanamide to urea.
Gene Name:
CA1
Uniprot ID:
P00915
Molecular Weight:
28870.0 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory10.7 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Hilvo M, Scozzafava A, Parkkila S, Supuran CT: Carbonic anhydrase inhibitors: Inhibition of the new membrane-associated isoform XV with phenols. Bioorg Med Chem Lett. 2008 Jun 15;18(12):3593-6. doi: 10.1016/j.bmcl.2008.04.077. Epub 2008 May 4. [18501600 ]
  2. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Essential for bone resorption and osteoclast differentiation (By similarity). Reversible hydration of carbon dioxide. Can hydrate cyanamide to urea. Involved in the regulation of fluid secretion into the anterior chamber of the eye. Contributes to intracellular pH regulation in the duodenal upper villous epithelium during proton-coupled peptide absorption. Stimulates the chloride-bicarbonate exchange activity of SLC26A6.
Gene Name:
CA2
Uniprot ID:
P00918
Molecular Weight:
29245.895 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory0.09 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Hilvo M, Scozzafava A, Parkkila S, Supuran CT: Carbonic anhydrase inhibitors: Inhibition of the new membrane-associated isoform XV with phenols. Bioorg Med Chem Lett. 2008 Jun 15;18(12):3593-6. doi: 10.1016/j.bmcl.2008.04.077. Epub 2008 May 4. [18501600 ]
  2. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide.
Gene Name:
CA12
Uniprot ID:
O43570
Molecular Weight:
39450.615 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory7.8 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Metal ion binding
Specific Function:
Reversible hydration of carbon dioxide.
Gene Name:
CA14
Uniprot ID:
Q9ULX7
Molecular Weight:
37667.37 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory42 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide.
Gene Name:
CA3
Uniprot ID:
P07451
Molecular Weight:
29557.215 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory8.2 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide. May stimulate the sodium/bicarbonate transporter activity of SLC4A4 that acts in pH homeostasis. It is essential for acid overload removal from the retina and retina epithelium, and acid release in the choriocapillaris in the choroid.
Gene Name:
CA4
Uniprot ID:
P22748
Molecular Weight:
35032.075 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory10.8 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide. Low activity.
Gene Name:
CA5A
Uniprot ID:
P35218
Molecular Weight:
34750.21 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory14.1 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide.
Gene Name:
CA5B
Uniprot ID:
Q9Y2D0
Molecular Weight:
36433.43 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory12.5 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide. Its role in saliva is unknown.
Gene Name:
CA6
Uniprot ID:
P23280
Molecular Weight:
35366.615 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory521 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide.
Gene Name:
CA7
Uniprot ID:
P43166
Molecular Weight:
29658.235 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory883 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]
General Function:
Zinc ion binding
Specific Function:
Reversible hydration of carbon dioxide. Participates in pH regulation. May be involved in the control of cell proliferation and transformation. Appears to be a novel specific biomarker for a cervical neoplasia.
Gene Name:
CA9
Uniprot ID:
Q16790
Molecular Weight:
49697.36 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
Inhibitory32.5 uMNot AvailableBindingDB 26190
References
  1. Innocenti A, Vullo D, Scozzafava A, Supuran CT: Carbonic anhydrase inhibitors: inhibition of mammalian isoforms I-XIV with a series of substituted phenols including paracetamol and salicylic acid. Bioorg Med Chem. 2008 Aug 1;16(15):7424-8. doi: 10.1016/j.bmc.2008.06.013. Epub 2008 Jun 13. [18579385 ]