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Record Information
Creation Date2014-09-11 02:04:30 UTC
Update Date2014-12-24 20:26:55 UTC
Accession NumberT3D4677
Common NameAzathioprine
ClassSmall Molecule
DescriptionAzathioprine is only found in individuals that have used or taken this drug. It is an immunosuppressive pro-drug. It is converted into 6-mercaptopurine in the body where it blocks purine metabolism and DNA synthesis.Azathioprine antagonizes purine metabolism and may inhibit synthesis of DNA, RNA, and proteins. It may also interfere with cellular metabolism and inhibit mitosis. Its mechanism of action is likely due to incorporation of thiopurine analogues into the DNA structure, causing chain termination and cytotoxicity.
Compound Type
  • Antimetabolite
  • Antimetabolite, Antineoplastic
  • Antirheumatic Agent
  • Drug
  • Ether
  • Immunosuppressive Agent
  • Metabolite
  • Organic Compound
  • Synthetic Compound
Chemical Structure
Chemical FormulaC9H7N7O2S
Average Molecular Mass277.263 g/mol
Monoisotopic Mass277.038 g/mol
CAS Registry Number446-86-6
IUPAC Name6-[(1-methyl-4-nitro-1H-imidazol-5-yl)sulfanyl]-7H-purine
Traditional Nameazathioprine
InChI IdentifierInChI=1S/C9H7N7O2S/c1-15-4-14-7(16(17)18)9(15)19-8-5-6(11-2-10-5)12-3-13-8/h2-4H,1H3,(H,10,11,12,13)
Chemical Taxonomy
Description belongs to the class of organic compounds known as diarylthioethers. These are organosulfur compounds containing a thioether group that is substituted by two aryl groups.
KingdomOrganic compounds
Super ClassOrganosulfur compounds
Sub ClassAryl thioethers
Direct ParentDiarylthioethers
Alternative Parents
  • Diarylthioether
  • 6-thiopurine
  • Imidazopyrimidine
  • Purine
  • Nitroaromatic compound
  • Nitroimidazole
  • N-substituted imidazole
  • Imidolactam
  • Pyrimidine
  • Azole
  • Imidazole
  • Heteroaromatic compound
  • C-nitro compound
  • Organic nitro compound
  • Azacycle
  • Organic oxoazanium
  • Organoheterocyclic compound
  • Organic 1,3-dipolar compound
  • Sulfenyl compound
  • Propargyl-type 1,3-dipolar organic compound
  • Allyl-type 1,3-dipolar organic compound
  • Organic nitrogen compound
  • Organonitrogen compound
  • Organic oxygen compound
  • Organopnictogen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organic zwitterion
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
Cellular Locations
  • Cytoplasm
  • Extracellular
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
AppearanceWhite powder.
Experimental Properties
Melting Point243.5°C
Boiling PointNot Available
Solubility1.07e+00 g/L
Predicted Properties
Water Solubility1.07 g/LALOGPS
pKa (Strongest Acidic)8.65ChemAxon
pKa (Strongest Basic)4ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count6ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area118.1 ŲChemAxon
Rotatable Bond Count3ChemAxon
Refractivity70.95 m³·mol⁻¹ChemAxon
Polarizability24.26 ųChemAxon
Number of Rings3ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-004i-9680000000-14a922ede69208f7d93d2017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot Available2021-10-12View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-001l-2950000000-4d3fb67844876c2178142017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-qTof , Positivesplash10-000x-0950000000-b6de6073310270167ffb2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-004i-0390000000-0d11d23373539cfb283c2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-000x-0950000000-b6de6073310270167ffb2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - , positivesplash10-001l-2950000000-4d3fb67844876c2178142017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 35V, Negativesplash10-004i-0390000000-58368875ea6ed88ee61c2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 15V, Negativesplash10-004i-0090000000-21d13daccc3ca63118292021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 30V, Negativesplash10-004i-0590000000-b73f9f2e26259b004f752021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 90V, Positivesplash10-01b9-7900000000-b14a64aca199c8b71caf2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 75V, Positivesplash10-0gir-6910000000-5e2cea2a00375e82d2942021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 15V, Positivesplash10-0006-0950000000-dd45895b2d199860f1572021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 30V, Positivesplash10-000x-2950000000-f4883419404f23b8f2a12021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 60V, Positivesplash10-0gir-5920000000-c941e300fe4d1869fd8e2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 45V, Positivesplash10-00lv-4930000000-c315bdc3abb371f4e4262021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 60V, Positivesplash10-0gir-5920000000-3d187b69fbd90dc9b4de2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 90V, Positivesplash10-01b9-7900000000-c328e8adab736ddf28192021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 60V, Negativesplash10-0a4i-0900000000-b07a1492f0de60ac50ce2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 90V, Negativesplash10-07vl-4900000000-3773c3f34878b3d9eef82021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 75V, Negativesplash10-0aor-2900000000-aa84765db89a7c5cac3d2021-09-20View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-004i-0090000000-127672e50f7d85ca73022016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-05i0-0090000000-7bb3b92e927e16854e1d2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a4i-9120000000-e50a6491ae4f28b8eeb02016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-004i-3090000000-df6cb72af7b792b5cdfb2016-08-04View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-004i-2490000000-b8ce493eef32ac50f4582016-08-04View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-00ba-5910000000-2134d4c288ab79f6a6892016-08-04View Spectrum
Toxicity Profile
Route of ExposureWell absorbed following oral administration.
Mechanism of ToxicityAzathioprine antagonizes purine metabolism and may inhibit synthesis of DNA, RNA, and proteins. It may also interfere with cellular metabolism and inhibit mitosis. Its mechanism of action is likely due to incorporation of thiopurine analogues into the DNA structure, causing chain termination and cytotoxicity.
MetabolismPrimarily converted to the active metabolites 6-mercaptopurine and 6-thioinosinic acid via a non-enzymatica process and glutathione transferases. Activation of 6-mercaptopurine occurs via hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and a series of multi-enzymatic processes involving kinases to form 6-thioguanine nucleotides (6-TGNs) as major metabolites Route of Elimination: Both compounds are rapidly eliminated from blood and are oxidized or methylated in erythrocytes and liver; no azathioprine or mercaptopurine is detectable in urine after 8 hours.
Toxicity ValuesThe oral LD50 for single doses of azathioprine in mice and rats are 2500 mg/kg and 400 mg/kg, respectively.
Lethal DoseNot Available
Carcinogenicity (IARC Classification)1, carcinogenic to humans. (4)
Uses/SourcesAzathioprine is used alone or in combination with other immunosuppressive therapy to prevent rejection following organ transplantation, and to treat an array of autoimmune diseases, including rheumatoid arthritis, pemphigus, systemic lupus erythematosus, Behcet's disease and other forms of vasculitis, autoimmune hepatitis, atopic dermatitis, myasthenia gravis, neuromyelitis optica (Devic's disease), restrictive lung disease, and others. It is also an important therapy and steroid-sparing agent for inflammatory bowel disease (such as Crohn's disease and ulcerative colitis) and for multiple sclerosis. In the United States it is currently approved by the Food and Drug Administration (FDA) for use in kidney transplantation from human donors, and for rheumatoid arthritis. Other uses are off-label. (Wikipedia)
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDDB00993
PubChem Compound ID2265
ChemSpider ID2178
UniProt IDNot Available
ChEBI ID2948
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkAzathioprine
Synthesis ReferenceNot Available
General References
  1. Konstantopoulou M, Belgi A, Griffiths KD, Seale JR, Macfarlane AW: Azathioprine-induced pancytopenia in a patient with pompholyx and deficiency of erythrocyte thiopurine methyltransferase. BMJ. 2005 Feb 12;330(7487):350-1. [15705694 ]
  2. Woodroffe R, Yao GL, Meads C, Bayliss S, Ready A, Raftery J, Taylor RS: Clinical and cost-effectiveness of newer immunosuppressive regimens in renal transplantation: a systematic review and modelling study. Health Technol Assess. 2005 May;9(21):1-179, iii-iv. [15899149 ]
  3. Gombar VK, Enslein K, Blake BW: Carcinogenicity of azathioprine: an S-AR investigation. Mutat Res. 1993 May;302(1):7-12. [7683109 ]
  4. 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


General Function:
Protein homodimerization activity
Specific Function:
Converts guanine to guanosine monophosphate, and hypoxanthine to inosine monophosphate. Transfers the 5-phosphoribosyl group from 5-phosphoribosylpyrophosphate onto the purine. Plays a central role in the generation of purine nucleotides through the purine salvage pathway.
Gene Name:
Uniprot ID:
Molecular Weight:
24579.155 Da
  1. Anstey A, Lear JT: Azathioprine: clinical pharmacology and current indications in autoimmune disorders. BioDrugs. 1998 Jan;9(1):33-47. [18020555 ]
  2. Dubinsky MC: Azathioprine, 6-mercaptopurine in inflammatory bowel disease: pharmacology, efficacy, and safety. Clin Gastroenterol Hepatol. 2004 Sep;2(9):731-43. [15354273 ]