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Record Information
StatusDetected but not Quantified
Creation Date2006-08-12 19:06:36 UTC
Update Date2020-04-23 20:56:19 UTC
Secondary Accession Numbers
  • HMDB0060880
  • HMDB03338
  • HMDB60880
Metabolite Identification
Common NameHydroxylamine
DescriptionHydroxylamine is a reactive chemical with formula NH2OH. It can be considered a hybrid of ammonia and water due to parallels it shares with each. At room temperature pure NH2OH is ordinarily a white, unstable crystalline, hygroscopic compound; however it is almost always encountered as an aqueous solution. A colorless inorganic compound (HONH2) used in organic synthesis and as a reducing agent, due to its ability to donate nitric oxide. Hydroxylamine may explode on heating. It is an irritant to the respiratory tract, skin, eyes, and other mucous membranes. It may be absorbed through the skin, is harmful if swallowed, and is a possible mutagen. NH2OH is an intermediate in the biological nitrification. The oxidation of NH3 is mediated by HAO (hydroxylamine oxidoreductase).
(1) HydroxylamineHMDB
Hydroxyamine hydrochlorideHMDB
Hydroxylamine chlorideHMDB
Hydroxylamine hydrochlorideHMDB
Hydroxylammonium chlorideHMDB
Oxammonium hydrochlorideHMDB
Chloride, hydroxylammoniumHMDB
Hydrochloride, hydroxylamineHMDB
Chemical FormulaH3NO
Average Molecular Weight33.0299
Monoisotopic Molecular Weight33.021463723
IUPAC Namehydroxylamine
Traditional Namehydroxylamine
CAS Registry Number7803-49-8
InChI Identifier
Chemical Taxonomy
Description Belongs to the class of inorganic compounds known as homogeneous other non-metal compounds. These are inorganic non-metallic compounds in which the largest atom belongs to the class of 'other non-metals'.
KingdomInorganic compounds
Super ClassHomogeneous non-metal compounds
ClassHomogeneous other non-metal compounds
Sub ClassNot Available
Direct ParentHomogeneous other non-metal compounds
Alternative ParentsNot Available
  • Homogeneous other non metal
Molecular FrameworkNot Available
External Descriptors

Route of exposure:


Biological location:


Biological role:

Physical Properties
Experimental Molecular Properties
Melting Point33 °CNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Molecular Properties
pKa (Strongest Acidic)17.65ChemAxon
pKa (Strongest Basic)3.94ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area46.25 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity7.85 m³·mol⁻¹ChemAxon
Polarizability2.78 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Predicted Spectral Properties

Collision Cross Sections

NameAdductTypeData SourceValueReference

Retention Indices


Not Available


Not Available


Spectrum TypeDescriptionSplash KeyDeposition DateView
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (3 TMS)splash10-00di-9800000000-40500c2ce42330f68e232014-06-16View Spectrum
GC-MSGC-MS Spectrum - GC-MS (3 TMS)splash10-001j-1900000000-380d2510f339c8852cae2014-06-16View Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-00di-9800000000-40500c2ce42330f68e232017-09-12View Spectrum
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-001j-1900000000-380d2510f339c8852cae2017-09-12View Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-00m1-1900000000-7c1a1a9c2955e5f4d75e2017-09-12View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-001i-9000000000-6a1320306a7bbc43c2582017-09-01View Spectrum


Spectrum TypeDescriptionSplash KeyDeposition DateView
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-001i-9000000000-17862dd274dc5ae95e9b2012-07-25View Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-001i-9000000000-c7d671f97d82bbe3e4582012-07-25View Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-001i-9000000000-36b50bedfc3b86b95fdf2012-07-25View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-9000000000-190eddac91b76eed90652017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-9000000000-190eddac91b76eed90652017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-001i-9000000000-190eddac91b76eed90652017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-9000000000-20928e005423160892f32017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-9000000000-20928e005423160892f32017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-001i-9000000000-20928e005423160892f32017-09-01View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-9000000000-6c136ec6f9ff4bb554452021-09-07View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-9000000000-6c136ec6f9ff4bb554452021-09-09View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-001i-9000000000-6c136ec6f9ff4bb554452021-09-09View Spectrum
Biological Properties
Cellular Locations
  • Cytoplasm (predicted from logP)
Biospecimen Locations
  • Blood
  • Urine
Tissue Locations
  • Epidermis
  • Fibroblasts
  • Kidney
  • Liver
  • Spleen
Normal Concentrations
BloodExpected but not QuantifiedNot QuantifiedNot AvailableNot AvailableNormal
      Not Available
UrineDetected but not QuantifiedNot QuantifiedNot AvailableNot AvailableNormal details
Abnormal Concentrations
UrineDetected but not QuantifiedNot QuantifiedAdult (>18 years old)BothBladder cancer details
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FooDB IDFDB007499
KNApSAcK IDNot Available
Chemspider ID766
KEGG Compound IDC00192
BiGG IDNot Available
Wikipedia LinkHydroxylamine
PubChem Compound787
PDB IDNot Available
ChEBI ID15429
Food Biomarker OntologyNot Available
VMH IDNot Available
MarkerDB IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Yang X, Arosio P, Chasteen ND: Molecular diffusion into ferritin: pathways, temperature dependence, incubation time, and concentration effects. Biophys J. 2000 Apr;78(4):2049-59. [PubMed:10733983 ]
  2. Atamna H, Robinson C, Ingersoll R, Elliott H, Ames BN: N-t-Butyl hydroxylamine is an antioxidant that reverses age-related changes in mitochondria in vivo and in vitro. FASEB J. 2001 Oct;15(12):2196-204. [PubMed:11641246 ]
  3. Cribb AE, Spielberg SP: Sulfamethoxazole is metabolized to the hydroxylamine in humans. Clin Pharmacol Ther. 1992 May;51(5):522-6. [PubMed:1587066 ]
  4. Alonso A, Meirelles NC, Tabak M: Stratum corneum intercellular lipid as compared to erythrocyte ghosts: an ESR study of thermotropic behavior and nitroxide reduction. Electron Spin Resonance. Physiol Chem Phys Med NMR. 1995;27(1):63-72. [PubMed:7617746 ]
  5. Fuchs J, Freisleben HJ, Podda M, Zimmer G, Milbradt R, Packer L: Nitroxide radical biostability in skin. Free Radic Biol Med. 1993 Oct;15(4):415-23. [PubMed:8225023 ]
  6. Kurian JR, Bajad SU, Miller JL, Chin NA, Trepanier LA: NADH cytochrome b5 reductase and cytochrome b5 catalyze the microsomal reduction of xenobiotic hydroxylamines and amidoximes in humans. J Pharmacol Exp Ther. 2004 Dec;311(3):1171-8. Epub 2004 Aug 9. [PubMed:15302896 ]
  7. Coleman MD, Jacobus DP: Reduction of dapsone hydroxylamine to dapsone during methaemoglobin formation in human erythrocytes in vitro--II. Movement of dapsone across a semipermeable membrane into erythrocytes and plasma. Biochem Pharmacol. 1993 Oct 19;46(8):1363-8. [PubMed:8240384 ]
  8. Lin J, Cashman JR: Detoxication of tyramine by the flavin-containing monooxygenase: stereoselective formation of the trans oxime. Chem Res Toxicol. 1997 Aug;10(8):842-52. [PubMed:9282832 ]
  9. Peng SX, Strojnowski MJ, Hu JK, Smith BJ, Eichhold TH, Wehmeyer KR, Pikul S, Almstead NG: Gas chromatographic-mass spectrometric analysis of hydroxylamine for monitoring the metabolic hydrolysis of metalloprotease inhibitors in rat and human liver microsomes. J Chromatogr B Biomed Sci Appl. 1999 Mar 5;724(1):181-7. [PubMed:10202971 ]
  10. Forsyth NR, Evans AP, Shay JW, Wright WE: Developmental differences in the immortalization of lung fibroblasts by telomerase. Aging Cell. 2003 Oct;2(5):235-43. [PubMed:14570231 ]
  11. Goda R, Nagai D, Akiyama Y, Nishikawa K, Ikemoto I, Aizawa Y, Nagata K, Yamazoe Y: Detection of a new N-oxidized metabolite of flutamide, N-[4-nitro-3-(trifluoromethyl)phenyl]hydroxylamine, in human liver microsomes and urine of prostate cancer patients. Drug Metab Dispos. 2006 May;34(5):828-35. Epub 2006 Feb 28. [PubMed:16507648 ]
  12. Winter HR, Unadkat JD: Identification of cytochrome P450 and arylamine N-acetyltransferase isoforms involved in sulfadiazine metabolism. Drug Metab Dispos. 2005 Jul;33(7):969-76. Epub 2005 Apr 20. [PubMed:15843491 ]
  13. Coleman MD: Dapsone: modes of action, toxicity and possible strategies for increasing patient tolerance. Br J Dermatol. 1993 Nov;129(5):507-13. [PubMed:8251346 ]