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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-02-26 21:23:01 UTC
Secondary Accession Numbers
  • HMDB01169
Metabolite Identification
Common Name4-Aminophenol
Description4-Aminophenol, also known as 4-aminobenzenol or 4-hydroxyaniline, belongs to the class of organic compounds known as aniline and substituted anilines. These are organic compounds containing an aminobenzene moiety. 4-Aminophenol is a very strong basic compound (based on its pKa). 4-Aminophenol is a potentially toxic compound. The compound is one of three isomeric aminophenols, the other two being 2-aminophenol and 3-aminophenol. Alternatively, the partial hydrogenation of nitrobenzene affords phenylhydroxylamine, which rearranges primarily to 4-aminophenol:C6H5NO2 + 2 H2 → C6H5NHOH + H2OC6H5NHOH → HOC6H4NH2It can be produced from nitrobenzene by electrolytic conversion to phenylhydroxylamine, which spontaneously rearranges to 4-aminophenol.4-Aminophenol is a building block used in organic chemistry. It is produced from phenol by nitration followed by reduction with iron. 4-Aminophenol (or para-aminophenol or p-aminophenol) is the organic compound with the formula H2NC6H4OH. The methylated derivatives N-methylaminophenol and N,N-dimethylaminophenol are of commercial value. Prominently, it is the final intermediate in the industrial synthesis of paracetamol. In the presence of a base, it oxidizes readily. Typically available as a white powder, it was commonly used as a developer for black-and-white film, marketed under the name Rodinal.
Fouramine pHMDB
4-Aminophenol hydrochlorideHMDB
p-Aminophenol phosphateHMDB
4-Aminophenol monosodium saltHMDB
4-Aminophenol, 3H-labeledHMDB
4-Aminophenol, ion(1+)HMDB
4-Aminophenol conjugate monoacidHMDB
4-Aminophenol monopotassium saltHMDB
4-Aminophenol, 18O-labeledHMDB
4-Aminophenol sulfateHMDB
4-Aminophenol sulfate (2:1)HMDB
Chemical FormulaC6H7NO
Average Molecular Weight109.1259
Monoisotopic Molecular Weight109.052763851
IUPAC Name4-aminophenol
Traditional Nameaminophenol
CAS Registry Number123-30-8
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as aniline and substituted anilines. These are organic compounds containing an aminobenzene moiety.
KingdomOrganic compounds
Super ClassBenzenoids
ClassBenzene and substituted derivatives
Sub ClassAniline and substituted anilines
Direct ParentAniline and substituted anilines
Alternative Parents
  • P-aminophenol
  • Aniline or substituted anilines
  • Aminophenol
  • 1-hydroxy-2-unsubstituted benzenoid
  • Phenol
  • Organic nitrogen compound
  • Organic oxygen compound
  • Organopnictogen compound
  • Hydrocarbon derivative
  • Primary amine
  • Organooxygen compound
  • Organonitrogen compound
  • Amine
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External Descriptors
Physiological effect

Health effect:


Route of exposure:


Biological location:


Naturally occurring process:


Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling Point187.5 °CNot Available
Water Solubility16 mg/mLNot Available
LogP0.04HANSCH,C ET AL. (1995)
Predicted Properties
Water Solubility121 g/LALOGPS
pKa (Strongest Acidic)10.4ChemAxon
pKa (Strongest Basic)5.43ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area46.25 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity32.74 m³·mol⁻¹ChemAxon
Polarizability11.23 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0a4i-6900000000-9c5bfea7a6ff3c845001Spectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0pe9-9300000000-8ff47e2157f6fbfe6754Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0f79-1890000000-c8247060f46131c693d1Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-03di-1927000000-b873199d9ac85605a4dfSpectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0a4i-6900000000-9c5bfea7a6ff3c845001Spectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0pe9-9300000000-8ff47e2157f6fbfe6754Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0f79-1890000000-c8247060f46131c693d1Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-03di-1927000000-b873199d9ac85605a4dfSpectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0a4i-5900000000-e64da39e73e3c0ea696cSpectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-060r-6900000000-2c6cd652b49e26ce3fceSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-03di-3900000000-906f96b14dfdad2310deSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-014i-9000000000-d56be0077647bc66e962Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-014i-9000000000-937794addf5b73c988e9Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , positivesplash10-03di-2900000000-1d20b6ad92e8fe4dcb55Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-03di-0900000000-da3b2114d9298a0363e7Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-03di-1900000000-b43943b1e137b2912b0fSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-00lr-9000000000-8ca8655366b90d8f42dfSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0a4i-0900000000-28f35dbe83fee57d4a70Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0a4i-0900000000-6aa4cd1a9d2a859fa70bSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0a7i-9300000000-177dcaf10b9e95cb409cSpectrum
MSMass Spectrum (Electron Ionization)splash10-0a4i-9700000000-00bffb48fd955696bcccSpectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
1D NMR13C NMR SpectrumNot AvailableSpectrum
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Blood
  • Urine
Tissue Locations
  • Epidermis
  • Spleen
Normal Concentrations
BloodDetected and Quantified10.00 (0.03-20.00) uMAdult (>18 years old)BothNormal details
UrineDetected but not QuantifiedNot QuantifiedAdult (>18 years old)BothNormal details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB022462
KNApSAcK IDNot Available
Chemspider ID392
KEGG Compound IDC02372
BioCyc IDCPD-259
BiGG IDNot Available
Wikipedia Link4-Aminophenol
PubChem Compound403
PDB IDNot Available
ChEBI ID17602
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB ID
Synthesis ReferenceZhu, Jianliang; Yang, Ying; Xu, Jinlai; Gu, Zhiqiang; Zhang, Xiaowei; Zheng, Zhigang; Li, Jianlin; Hao, Xiangyang. Method for preparation of p-aminophenol. Faming Zhuanli Shenqing Gongkai Shuomingshu (2005), 6 pp.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Lampinen M, Bondesson U, Fredriksson E, Hedeland M: Validation of a method for quantification of ketobemidone in human plasma with liquid chromatography-tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Jun 15;789(2):347-54. [PubMed:12742125 ]
  2. Clark PM, Clark JD, Wheatley T: Urine discoloration after acetaminophen overdose. Clin Chem. 1986 Sep;32(9):1777-8. [PubMed:3742803 ]
  3. Kanishchev PA, Bereza NM, Seniuk VF, Perevziaka AV: [Quantitative determination of blood loss from the gastrointestinal tract using Metol in chronic diseases of the digestive organs]. Lab Delo. 1989;(3):36-8. [PubMed:2469837 ]
  4. Xu Y, Halsall B, Heineman WR: Heterogeneous enzyme immunoassay of alpha-fetoprotein in maternal serum by flow-injection amperometric detection of 4-aminophenol. Clin Chem. 1990 Nov;36(11):1941-4. [PubMed:1700742 ]
  5. Bomhard EM, Herbold BA: Genotoxic activities of aniline and its metabolites and their relationship to the carcinogenicity of aniline in the spleen of rats. Crit Rev Toxicol. 2005 Dec;35(10):783-835. [PubMed:16468500 ]
  6. Nohynek GJ, Duche D, Garrigues A, Meunier PA, Toutain H, Leclaire J: Under the skin: Biotransformation of para-aminophenol and para-phenylenediamine in reconstructed human epidermis and human hepatocytes. Toxicol Lett. 2005 Sep 15;158(3):196-212. [PubMed:15890478 ]
  7. Van Bocxlaer JF, Clauwaert KM, Lambert WE, De Leenheer AP: Quantitative colorimetric determination of urinary p-aminophenol with an automated analyzer. Clin Chem. 1997 Apr;43(4):627-34. [PubMed:9105264 ]
  8. Gil EP, Tang HT, Halsall HB, Heineman WR, Misiego AS: Competitive heterogeneous enzyme immunoassay for theophylline by flow-injection analysis with electrochemical detection of p-aminophenol. Clin Chem. 1990 Apr;36(4):662-5. [PubMed:2138937 ]
  9. Arndt CA, Colvin OM, Balis FM, Lester CM, Johnson G, Poplack DG: Intrathecal administration of 4-hydroperoxycyclophosphamide in rhesus monkeys. Cancer Res. 1987 Nov 15;47(22):5932-4. [PubMed:3664493 ]
  10. Hegedus ZL, Nayak U: Para-aminophenol and structurally related compounds as intermediates in lipofuscin formation and in renal and other tissue toxicities. Arch Int Physiol Biochim Biophys. 1991 Feb;99(1):99-105. [PubMed:1713494 ]