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Record Information
Version3.6
Creation Date2005-11-16 15:48:42 UTC
Update Date2016-02-11 01:02:43 UTC
HMDB IDHMDB00466
Secondary Accession NumbersNone
Metabolite Identification
Common Name3-Methylindole
Description3-Methylindole, or skatole, can be found as a white crystalline or fine powder solid, and it browns upon aging. It is nitrogenous and one of the rings is a pyrrole. This is probably the reason it's so foul smelling. It is soluble in alcohol and benzene and it gives violet color in potassium ferrocyanide (K4Fe(CN)6.3H2O) and sulfuric acid (H2SO4). Skatole has a double ring system which displays aromaticity that comes from the lone pair electrons on the nitrogen. It is continuous (all atoms in the ring are sp2 hybridized), planar, and follows the 4n+2 rule because it has 10 pi electrons. It can be synthesized through a Fischer indole synthesis which was developed by Emil Fischer.In a 1994 report released by five top cigarette companies, skatole was listed as one of the 599 additives to cigarettes. It is a flavoring ingredient. 3-Methylindole is a mildly toxic white crystalline organic compound with chemical formula C9H9N and CAS number 83-34-1. The compound belongs to the indole family and has a methyl substituent in position 3 of the indole ring. It occurs naturally in feces (it is produced from tryptophan in the mammalian digestive tract), beets, and coal tar, and has a strong fecal odor. In low concentrations it has a flowery smell and is found in several flowers and essential oils, including those of orange blossoms, jasmine, and Ziziphus mauritiana. It is used as a fragrance and fixative in many perfumes and as an aroma compound. Its name is derived from skato, the Greek word for dung.
Structure
Thumb
Synonyms
ValueSource
3-Methyl-4,5-benzopyrroleChEBI
3-MethylindoleChEBI
beta-MethylindoleChEBI
SkatolChEBI
b-MethylindoleGenerator
β-methylindoleGenerator
3-Methyl-1H-indoleHMDB
3-MIHMDB
ScatoleHMDB
Chemical FormulaC9H9N
Average Molecular Weight131.1745
Monoisotopic Molecular Weight131.073499293
IUPAC Name3-methyl-1H-indole
Traditional Namescatole
CAS Registry Number83-34-1
SMILES
CC1=CNC2=C1C=CC=C2
InChI Identifier
InChI=1S/C9H9N/c1-7-6-10-9-5-3-2-4-8(7)9/h2-6,10H,1H3
InChI KeyInChIKey=ZFRKQXVRDFCRJG-UHFFFAOYSA-N
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as indoles. These are compounds containing an indole moiety, which consists of pyrrole ring fused to benzene to form 2,3-benzopyrrole.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassIndoles and derivatives
Sub ClassIndoles
Direct ParentIndoles
Alternative Parents
Substituents
  • Indole
  • Benzenoid
  • Substituted pyrrole
  • Heteroaromatic compound
  • Pyrrole
  • Azacycle
  • Hydrocarbon derivative
  • Organonitrogen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Ontology
StatusDetected but not Quantified
Origin
  • Endogenous
BiofunctionNot Available
ApplicationNot Available
Cellular locations
  • Membrane (predicted from logP)
Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting Point97.5 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility0.498 mg/mLNot Available
LogP2.60HANSCH,C ET AL. (1995)
Predicted Properties
PropertyValueSource
Water Solubility3.09 mg/mLALOGPS
logP2.58ALOGPS
logP2.59ChemAxon
logS-1.6ALOGPS
pKa (Strongest Acidic)17.48ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area15.79 Å2ChemAxon
Rotatable Bond Count0ChemAxon
Refractivity42.19 m3·mol-1ChemAxon
Polarizability14.95 Å3ChemAxon
Number of Rings2ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-001i-0900000000-a7cd474bc90f9a0227e5View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-014i-2900000000-cb7f6d8c4ad7b0a1523bView in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-000l-9200000000-e9a200fb7b8fc93ced48View in MoNA
LC-MS/MSLC-MS/MS Spectrum - EI-B (HITACHI M-80) , Positivesplash10-0ufr-9200000000-7120fbb6f78f440ff725View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-0900000000-355610a12cde08bb25c8View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-0900000000-36a1bcb0093fec9dd5c5View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0zfr-3900000000-d8aebbf9a6779cddc735View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-0900000000-ed646ab44a1fcc84725bView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-0900000000-ed6f0939d3598782a893View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0f89-2900000000-a801a40b2fcba369d3d4View in MoNA
MSMass Spectrum (Electron Ionization)splash10-001i-2900000000-dba6ed7df0e1ee94cafeView in MoNA
1D NMR1H NMR SpectrumNot Available
1D NMR1H NMR SpectrumNot Available
1D NMR13C NMR SpectrumNot Available
2D NMR[1H,13C] 2D NMR SpectrumNot Available
Biological Properties
Cellular Locations
  • Membrane (predicted from logP)
Biofluid Locations
  • Feces
  • Saliva
Tissue LocationNot Available
PathwaysNot Available
Normal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
FecesDetected but not QuantifiedNot ApplicableNot SpecifiedNot Specified
Normal
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Normal
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Normal
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Normal
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Normal
details
SalivaDetected but not QuantifiedNot ApplicableAdult (>18 years old)Not SpecifiedNormal details
Abnormal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Nonalcoholic fatty liver disease (NAFLD)
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Campylobacter jejuni infection
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Clostridium difficile infection
details
FecesDetected but not QuantifiedNot ApplicableAdult (>18 years old)Both
Ulcerative Colitis
details
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB010993
KNApSAcK IDC00001430
Chemspider ID6480
KEGG Compound IDC08313
BioCyc IDSKATOLE
BiGG IDNot Available
Wikipedia Link3-methylindole
NuGOwiki LinkHMDB00466
Metagene LinkHMDB00466
METLIN ID5453
PubChem Compound6736
PDB IDNot Available
ChEBI ID9171
References
Synthesis ReferenceXu, Jianguo; Xu, Lili; Shi, Hongxin. Synthesis of 3-methylindole and its new purification method. Huagong Shengchan Yu Jishu (2005), 12(4), 12-14.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Karlin DA, Mastromarino AJ, Jones RD, Stroehlein JR, Lorentz O: Fecal skatole and indole and breath methane and hydrogen in patients with large bowel polyps or cancer. J Cancer Res Clin Oncol. 1985;109(2):135-41. [3980562 ]
  2. Moore JG, Jessop LD, Osborne DN: Gas-chromatographic and mass-spectrometric analysis of the odor of human feces. Gastroenterology. 1987 Dec;93(6):1321-9. [3678751 ]
  3. Cooke M, Leeves N, White C: Time profile of putrescine, cadaverine, indole and skatole in human saliva. Arch Oral Biol. 2003 Apr;48(4):323-7. [12663078 ]
  4. Zuccato E, Venturi M, Di Leo G, Colombo L, Bertolo C, Doldi SB, Mussini E: Role of bile acids and metabolic activity of colonic bacteria in increased risk of colon cancer after cholecystectomy. Dig Dis Sci. 1993 Mar;38(3):514-9. [8444084 ]
  5. Muller T, Thissen R, Braun S, Dott W, Fischer G: (M)VOC and composting facilities. Part 2: (M)VOC dispersal in the environment. Environ Sci Pollut Res Int. 2004;11(3):152-7. [15259697 ]
  6. Codipilly DP, Kaufman HW, Kleinberg I: Use of a novel group of oral malodor measurements to evaluate an anti-oral malodor mouthrinse (TriOralTM) in humans. J Clin Dent. 2004;15(4):98-104. [15794454 ]

Enzymes

General function:
Secondary metabolites biosynthesis, transport and catabolism
Specific function:
May be involved in the metabolism of various pneumotoxicants including naphthalene. Is able to dealkylate ethoxycoumarin, propoxycoumarin, and pentoxyresorufin but possesses no activity toward ethoxyresorufin and only trace dearylation activity toward benzyloxyresorufin. Bioactivates 3-methylindole (3MI) by dehydrogenation to the putative electrophile 3-methylene-indolenine.
Gene Name:
CYP2F1
Uniprot ID:
P24903
Molecular weight:
55500.64