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Record Information
StatusExpected but not Quantified
Creation Date2013-05-17 01:25:13 UTC
Update Date2019-07-23 07:14:28 UTC
Secondary Accession Numbers
  • HMDB60499
Metabolite Identification
Common NameNPC
DescriptionNPC is a metabolite of irinotecan. Irinotecan is a drug used for the treatment of cancer. Irinotecan prevents DNA from unwinding by inhibition of topoisomerase 1. In chemical terms, it is a semisynthetic analogue of the natural alkaloid camptothecin. Its main use is in colon cancer, in particular, in combination with other chemotherapy agents. This includes the regimen FOLFIRI, which consists of infusional 5-fluorouracil, leucovorin, and irinotecan. Irinotecan received accelerated approval by the U.S. (Wikipedia) Irinotecan is subjected to be shunted between CYP3A4 mediated oxidative metabolism to form two inactive metabolites APC or NPC and tissue carboxylesterase mediated hydrolysis to form SN-38 which is eventually detoxified via glucuronidation by UGT1A1 to form SN-38G. (PMID: 12570720 ) The active metabolite of irinotecan (CPT-11), 7-ethyl-10-hydroxycamptothecin (SN-38), is either formed through enzymatic cleavage of CPT-11 by carboxyl esterases (CEs) or through cytochrome P-450 3A-mediated oxidation to 7-ethyl-10-[4-(1-piperidino)-1-amino] carbonyloxycamptothecin (NPC) and a subsequent conversion by CE. (PMID: 10999728 )
SynonymsNot Available
Chemical FormulaC28H30N4O6
Average Molecular Weight518.561
Monoisotopic Molecular Weight518.216534712
IUPAC Name(19S)-10,19-diethyl-19-hydroxy-14,18-dioxo-17-oxa-3,13-diazapentacyclo[²,¹¹.0⁴,⁹.0¹⁵,²⁰]henicosa-1(21),2(11),3,5,7,9,15(20)-heptaen-7-yl 4-aminopiperidine-1-carboxylate
Traditional NameNPC
CAS Registry NumberNot Available
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as camptothecins. These are heterocyclic compounds comprising a planar pentacyclic ring structure, that includes a pyrrolo[3,4-beta]-quinoline moiety (rings A, B and C), conjugated pyridone moiety (ring D) and one chiral center at position 20 within the alpha-hydroxy lactone ring with (S) configuration (the E-ring).
KingdomOrganic compounds
Super ClassAlkaloids and derivatives
Sub ClassNot Available
Direct ParentCamptothecins
Alternative Parents
  • Camptothecin
  • Pyranopyridine
  • Quinoline
  • Piperidinecarboxylic acid
  • 4-aminopiperidine
  • Pyridinone
  • Piperidine
  • Pyridine
  • Benzenoid
  • Carbamic acid ester
  • Tertiary alcohol
  • Heteroaromatic compound
  • Amino acid or derivatives
  • Carboxylic acid ester
  • Lactam
  • Lactone
  • Carbonic acid derivative
  • Oxacycle
  • Azacycle
  • Organoheterocyclic compound
  • Carboxylic acid derivative
  • Monocarboxylic acid or derivatives
  • Hydrocarbon derivative
  • Organonitrogen compound
  • Primary aliphatic amine
  • Organooxygen compound
  • Organopnictogen compound
  • Alcohol
  • Primary amine
  • Carbonyl group
  • Organic oxygen compound
  • Organic nitrogen compound
  • Organic oxide
  • Amine
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors


Biological location:


Naturally occurring process:


Biological role:

Physical Properties
StateNot Available
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility0.17 g/LALOGPS
pKa (Strongest Acidic)11.72ChemAxon
pKa (Strongest Basic)9.97ChemAxon
Physiological Charge1ChemAxon
Hydrogen Acceptor Count6ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area135.29 ŲChemAxon
Rotatable Bond Count4ChemAxon
Refractivity139.12 m³·mol⁻¹ChemAxon
Polarizability56.6 ųChemAxon
Number of Rings6ChemAxon
Rule of FiveNoChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-0002-3001900000-8c258c33503227186d90Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-020s-7100190000-57a04835b3260d62318fSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0uxr-1601190000-f7732258181788a4f6a6Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0fc0-4914410000-8e809aa535ad79d20553Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0zgi-9400000000-63746df667fed14115e3Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-014i-1401590000-893de4cd7001406d84a4Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-00vm-3906840000-17ebfe5e43ffd714d8c8Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-002e-9725100000-daa9ad1f7a2a7c152ce2Spectrum
Biological Properties
Cellular LocationsNot Available
Biospecimen Locations
  • Blood
  • Urine
Tissue Locations
  • Kidney
  • Liver
Normal Concentrations
BloodExpected but not Quantified Not AvailableNot AvailableNormal
    UrineExpected but not Quantified Not AvailableNot AvailableNormal
      Abnormal Concentrations
      Not Available
      Associated Disorders and Diseases
      Disease ReferencesNone
      Associated OMIM IDsNone
      DrugBank IDNot Available
      Phenol Explorer Compound IDNot Available
      FooDB IDNot Available
      KNApSAcK IDNot Available
      Chemspider IDNot Available
      KEGG Compound IDC16543
      BioCyc IDNot Available
      BiGG IDNot Available
      Wikipedia LinkNPC
      METLIN IDNot Available
      PubChem Compound11756356
      PDB IDNot Available
      ChEBI IDNot Available
      Food Biomarker OntologyNot Available
      VMH IDNot Available
      Synthesis ReferenceNot Available
      Material Safety Data Sheet (MSDS)Not Available
      General References
      1. Magrane M: UniProt Knowledgebase: a hub of integrated protein data. Database (Oxford). 2011 Mar 29;2011:bar009. doi: 10.1093/database/bar009. Print 2011. [PubMed:21447597 ]
      2. Ma MK, McLeod HL: Lessons learned from the irinotecan metabolic pathway. Curr Med Chem. 2003 Jan;10(1):41-9. [PubMed:12570720 ]
      3. Kehrer DF, Yamamoto W, Verweij J, de Jonge MJ, de Bruijn P, Sparreboom A: Factors involved in prolongation of the terminal disposition phase of SN-38: clinical and experimental studies. Clin Cancer Res. 2000 Sep;6(9):3451-8. [PubMed:10999728 ]


      General function:
      Lipid transport and metabolism
      Specific function:
      Involved in the detoxification of xenobiotics and in the activation of ester and amide prodrugs. Hydrolyzes aromatic and aliphatic esters, but has no catalytic activity toward amides or a fatty acyl-CoA ester. Hydrolyzes the methyl ester group of cocaine to form benzoylecgonine. Catalyzes the transesterification of cocaine to form cocaethylene. Displays fatty acid ethyl ester synthase activity, catalyzing the ethyl esterification of oleic acid to ethyloleate.
      Gene Name:
      Uniprot ID:
      Molecular weight:
      NPC + Water → SN-38 + 4-Amino-1-piperidinecarboxylic aciddetails
      General function:
      Lipid transport and metabolism
      Specific function:
      Involved in the detoxification of xenobiotics and in the activation of ester and amide prodrugs. Shows high catalytic efficiency for hydrolysis of cocaine, 4-methylumbelliferyl acetate, heroin and 6-monoacetylmorphine.
      Gene Name:
      Uniprot ID:
      Molecular weight:
      NPC + Water → SN-38 + 4-Amino-1-piperidinecarboxylic aciddetails