Record Information
Version1.0
Creation date2010-04-08 22:06:11 UTC
Update date2019-11-26 02:59:56 UTC
Primary IDFDB004302
Secondary Accession Numbers
  • FDB010993
Chemical Information
FooDB Name2(or 3)-methylindole
Description3-methylindole, also known as skatol or 3-methyl-4,5-benzopyrrole, is a member of the class of compounds known as 3-methylindoles. 3-methylindoles are aromatic heterocyclic compounds that contain an indole moiety substituted at the 3-position with a methyl group. 3-methylindole is slightly soluble (in water) and an extremely weak acidic compound (based on its pKa). 3-methylindole is a very strong, animal, and civet tasting compound found in common beet and red beetroot, which makes 3-methylindole a potential biomarker for the consumption of these food products. 3-methylindole can be found primarily in feces and saliva. Skatole or 3-methylindole is a mildly toxic white crystalline organic compound belonging to the indole family. It occurs naturally in feces (it is produced from tryptophan in the mammalian digestive tract) 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 the Greek root skato- meaning "dung". Skatole was discovered in 1877 by the German physician Ludwig Brieger (1849–1919). Skatole is also used by U.S. military in its non-lethal weaponry; specifically, malodorants .
CAS Number83-34-1
Structure
Thumb
Synonyms
SynonymSource
3-Methyl-4,5-benzopyrroleChEBI
beta-MethylindoleChEBI
SkatolChEBI
b-MethylindoleGenerator
Β-methylindoleGenerator
3-Methyl-1H-indoleHMDB
3-MIHMDB
ScatoleHMDB
SkatoleHMDB
3 MethylindoleHMDB
3-MethylindoleChEBI
Predicted Properties
PropertyValueSource
Water Solubility3.09 g/LALOGPS
logP2.58ALOGPS
logP2.59ChemAxon
logS-1.6ALOGPS
pKa (Strongest Acidic)17.48ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area15.79 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity42.19 m³·mol⁻¹ChemAxon
Polarizability14.95 ųChemAxon
Number of Rings2ChemAxon
BioavailabilityYesChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleNoChemAxon
Chemical FormulaC9H9N
IUPAC name3-methyl-1H-indole
InChI IdentifierInChI=1S/C9H9N/c1-7-6-10-9-5-3-2-4-8(7)9/h2-6,10H,1H3
InChI KeyZFRKQXVRDFCRJG-UHFFFAOYSA-N
Isomeric SMILESCC1=CNC2=C1C=CC=C2
Average Molecular Weight131.1745
Monoisotopic Molecular Weight131.073499293
Classification
Description Belongs to the class of organic compounds known as 3-methylindoles. These are aromatic heterocyclic compounds that contain an indole moiety substituted at the 3-position with a methyl group.
KingdomOrganic compounds
Super ClassOrganoheterocyclic compounds
ClassIndoles and derivatives
Sub ClassIndoles
Direct Parent3-methylindoles
Alternative Parents
Substituents
  • 3-methylindole
  • Benzenoid
  • Substituted pyrrole
  • Heteroaromatic compound
  • Pyrrole
  • Azacycle
  • Organic nitrogen compound
  • Organopnictogen compound
  • Hydrocarbon derivative
  • Organonitrogen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Ontology
Disposition

Route of exposure:

Source:

Biological location:

Physico-Chemical Properties - Experimental
Physico-Chemical Properties - Experimental
PropertyValueReference
Physical stateNot Available
Physical DescriptionNot Available
Mass CompositionNot Available
Melting PointNot Available
Boiling PointNot Available
Experimental Water SolubilityNot Available
Experimental logPNot Available
Experimental pKaNot Available
Isoelectric pointNot Available
ChargeNot Available
Optical RotationNot Available
Spectroscopic UV DataNot Available
DensityNot Available
Refractive IndexNot Available
Spectra
Spectra
EI-MS/GC-MS
TypeDescriptionSplash KeyView
EI-MSMass Spectrum (Electron Ionization)splash10-001i-2900000000-dba6ed7df0e1ee94cafe2015-03-01View Spectrum
GC-MS2(or 3)-methylindole, non-derivatized, GC-MS Spectrumsplash10-0ufr-9200000000-251c9585af60abc11fb1Spectrum
GC-MS2(or 3)-methylindole, non-derivatized, GC-MS Spectrumsplash10-0ufr-9200000000-251c9585af60abc11fb1Spectrum
Predicted GC-MS2(or 3)-methylindole, non-derivatized, Predicted GC-MS Spectrum - 70eV, Positivesplash10-001i-1900000000-f9bb0d50c5d49c2c6c4aSpectrum
Predicted GC-MS2(or 3)-methylindole, non-derivatized, Predicted GC-MS Spectrum - 70eV, PositiveNot AvailableSpectrum
Predicted GC-MS2(or 3)-methylindole, non-derivatized, Predicted GC-MS Spectrum - 70eV, PositiveNot AvailableSpectrum
MS/MS
TypeDescriptionSplash KeyView
MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-001i-0900000000-a7cd474bc90f9a0227e52012-07-24View Spectrum
MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-014i-2900000000-cb7f6d8c4ad7b0a1523b2012-07-24View Spectrum
MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-000l-9200000000-e9a200fb7b8fc93ced482012-07-24View Spectrum
MS/MSLC-MS/MS Spectrum - EI-B (HITACHI M-80) , Positivesplash10-0ufr-9200000000-7120fbb6f78f440ff7252012-08-31View Spectrum
MS/MSLC-MS/MS Spectrum - Linear Ion Trap , negativesplash10-002b-9800000000-a8de490dffcbc2cb0c242017-09-14View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-0900000000-355610a12cde08bb25c82015-04-24View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-0900000000-36a1bcb0093fec9dd5c52015-04-24View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0zfr-3900000000-d8aebbf9a6779cddc7352015-04-24View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-0900000000-ed646ab44a1fcc84725b2015-04-25View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-0900000000-ed6f0939d3598782a8932015-04-25View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0f89-2900000000-a801a40b2fcba369d3d42015-04-25View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-0900000000-244a9c7ac26f199509262021-09-23View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-0900000000-e7c79bc3a884b9bd7abe2021-09-23View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-004i-1900000000-e057600f7f225ff9cec22021-09-23View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-0900000000-f53b130d6fbd7a49b7bd2021-09-24View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-0900000000-92ee6b9af4d8ea4f32d42021-09-24View Spectrum
Predicted MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0v00-7900000000-f01b3fb9a64effb7bb2e2021-09-24View Spectrum
NMR
TypeDescriptionView
1D NMR1H NMR Spectrum (1D, 600 MHz, H2O, experimental)Spectrum
1D NMR1H NMR Spectrum (1D, 400 MHz, CDCl3, experimental)Spectrum
1D NMR13C NMR Spectrum (1D, 25.16 MHz, CDCl3, experimental)Spectrum
1D NMR13C NMR Spectrum (1D, 100 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 100 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 1000 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 1000 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 200 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 200 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 300 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 300 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 400 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 400 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 500 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 500 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 600 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 600 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 700 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 700 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 800 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 800 MHz, D2O, predicted)Spectrum
1D NMR13C NMR Spectrum (1D, 900 MHz, D2O, predicted)Spectrum
1D NMR1H NMR Spectrum (1D, 900 MHz, D2O, predicted)Spectrum
2D NMR[1H, 13C]-HSQC NMR Spectrum (2D, 600 MHz, CDCl3, experimental)Spectrum
ChemSpider IDNot Available
ChEMBL IDNot Available
KEGG Compound IDNot Available
Pubchem Compound IDNot Available
Pubchem Substance IDNot Available
ChEBI IDNot Available
Phenol-Explorer IDNot Available
DrugBank IDNot Available
HMDB IDNot Available
CRC / DFC (Dictionary of Food Compounds) IDNot Available
EAFUS IDNot Available
Dr. Duke ID2(OR_3)-METHYLINDOLE
BIGG IDNot Available
KNApSAcK IDNot Available
HET IDNot Available
Food Biomarker OntologyNot Available
VMH IDNot Available
Flavornet IDNot Available
GoodScent IDNot Available
SuperScent IDNot Available
Wikipedia IDNot Available
Phenol-Explorer Metabolite IDNot Available
Duplicate IDSNot Available
Old DFC IDSNot Available
Associated Foods
FoodContent Range AverageReference
FoodReference
Biological Effects and Interactions
Health Effects / BioactivitiesNot Available
EnzymesNot Available
PathwaysNot Available
MetabolismNot Available
BiosynthesisNot Available
Organoleptic Properties
Flavours
FlavorCitations
mothball
  1. Arn, H, Acree TE. “Flavornet: A database of aroma compounds based on odor potency in natural products”. Developments in Food Science 40 (1998): 27. doi:10.1016/S0167-4501(98)80029-0
fecal
  1. Arn, H, Acree TE. “Flavornet: A database of aroma compounds based on odor potency in natural products”. Developments in Food Science 40 (1998): 27. doi:10.1016/S0167-4501(98)80029-0
Files
MSDSNot Available
References
Synthesis ReferenceNot Available
General ReferenceNot Available
Content Reference— Duke, James. 'Dr. Duke's Phytochemical and Ethnobotanical Databases. United States Department of Agriculture.' Agricultural Research Service, Accessed April 27 (2004).