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Record Information
Version2.0
Creation Date2014-08-29 04:47:27 UTC
Update Date2014-12-24 20:26:35 UTC
Accession NumberT3D3962
Identification
Common NameEquol
ClassSmall Molecule
DescriptionEquol is a metabolite of daidzein, a phytoestrogen common in the human diet and abundant in soy. Intestinal bacteria in humans can reduce daidzein to equol, and can be found in normal human urine. The clinical effectiveness of soy isoflavones may be a function of the ability to biotransform soy isoflavones to the more potent estrogenic metabolite, equol, which may enhance the actions of soy isoflavones, owing to its greater affinity for estrogen receptors, unique antiandrogenic properties, and superior antioxidant activity. However, not all individuals consuming daidzein produce equol. Only approximately one-third to one-half of the population is able to metabolize daidzein to equol. This high variability in equol production is presumably attributable to interindividual differences in the composition of the intestinal microflora, which may play an important role in the mechanisms of action of isoflavones. (1, 2).
Compound Type
  • Animal Toxin
  • Ether
  • Food Toxin
  • Industrial/Workplace Toxin
  • Metabolite
  • Natural Compound
  • Organic Compound
Chemical Structure
Thumb
Synonyms
Synonym
(-)-(S)-Equol
(-)-Equol
(S)-(-)-4',7-Isoflavandiol
(S)-3,4-dihydro-3-(4-Hydroxyphenyl)-2H-1-benzopyran-7-ol
(S)-Equol
4',7-Dihydroxyisoflavan
4',7-Isoflavandiol
Chemical FormulaC15H14O3
Average Molecular Mass242.270 g/mol
Monoisotopic Mass242.094 g/mol
CAS Registry Number531-95-3
IUPAC Name(3S)-3-(4-hydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-7-ol
Traditional Name(-)-equol
SMILES[H][C@@]1(COC2=C(C1)C=CC(O)=C2)C1=CC=C(O)C=C1
InChI IdentifierInChI=1S/C15H14O3/c16-13-4-1-10(2-5-13)12-7-11-3-6-14(17)8-15(11)18-9-12/h1-6,8,12,16-17H,7,9H2/t12-/m1/s1
InChI KeyInChIKey=ADFCQWZHKCXPAJ-GFCCVEGCSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as isoflavanols. These are polycyclic compounds containing a hydroxylated isoflavan skeleton.
KingdomOrganic compounds
Super ClassPhenylpropanoids and polyketides
ClassIsoflavonoids
Sub ClassIsoflavans
Direct ParentIsoflavanols
Alternative Parents
Substituents
  • Hydroxyisoflavonoid
  • Isoflavanol
  • Chromane
  • Benzopyran
  • 1-benzopyran
  • Alkyl aryl ether
  • 1-hydroxy-2-unsubstituted benzenoid
  • Phenol
  • Monocyclic benzene moiety
  • Benzenoid
  • Ether
  • Oxacycle
  • Organoheterocyclic compound
  • Organooxygen compound
  • Hydrocarbon derivative
  • Organic oxygen compound
  • Aromatic heteropolycyclic compound
Molecular FrameworkAromatic heteropolycyclic compounds
External Descriptors
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Membrane
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceWhite powder.
Experimental Properties
PropertyValue
Melting Point189.5°C
Boiling PointNot Available
SolubilityNot Available
LogPNot Available
Predicted Properties
PropertyValueSource
Water Solubility0.044 g/LALOGPS
logP2.91ALOGPS
logP3.19ChemAxon
logS-3.7ALOGPS
pKa (Strongest Acidic)9.63ChemAxon
pKa (Strongest Basic)-4.9ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count2ChemAxon
Polar Surface Area49.69 ŲChemAxon
Rotatable Bond Count1ChemAxon
Refractivity68.96 m³·mol⁻¹ChemAxon
Polarizability25.81 ųChemAxon
Number of Rings3ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-03dl-2590000000-de6943a0e29cb74d29c42017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (2 TMS) - 70eV, Positivesplash10-00di-6439000000-bd3446db9a81b442105b2017-10-06View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, PositiveNot Available2021-10-12View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-006x-0890000000-7e7596ef550328bb2d8b2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00di-0950000000-eb2fba880af94e2ffaa42016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0adi-5910000000-ae99af1d6277808c807a2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0006-0390000000-9e81ff09baf0494659552016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0006-0390000000-23c63d12aef21bc1a2fe2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0603-4930000000-18ce0b21dd8e144014a52016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0005-0960000000-9edad7cf7d51f7a71fee2021-09-21View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0006-0590000000-19e7c74a42b427564aac2021-09-21View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-056r-4930000000-a7500058dae2b15f912b2021-09-21View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-006x-0970000000-7b598fa2edd4a41a1f9b2021-09-25View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-00kf-1970000000-4a2a37c7a8d430f4f1642021-09-25View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-014i-3910000000-5790b5708e0e13e02c982021-09-25View Spectrum
Toxicity Profile
Route of ExposureNot Available
Mechanism of ToxicityNot Available
MetabolismNot Available
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)No indication of carcinogenicity to humans (not listed by IARC).
Uses/SourcesIntestinal bacteria in humans can reduce daidzein to equol, and can be found in normal human urine.
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDHMDB02209
PubChem Compound ID91469
ChEMBL IDCHEMBL198877
ChemSpider ID82594
KEGG IDC14131
UniProt IDNot Available
OMIM ID
ChEBI ID428126
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkEquol
References
Synthesis ReferenceWang, Xiu-Ling; Hur, Hor-Gil; Lee, Je Hyeon; Kim, Ki Tae; Kim, Su-Il. Enantioselective synthesis of S-equol from dihydrodaidzein by a newly isolated anaerobic human intestinal bacterium. Applied and Environmental Microbiology (2005), 71(1), 214-219
MSDSLink
General References
  1. Moors S, Blaszkewicz M, Bolt HM, Degen GH: Simultaneous determination of daidzein, equol, genistein and bisphenol A in human urine by a fast and simple method using SPE and GC-MS. Mol Nutr Food Res. 2007 Jul;51(7):787-98. [17579895 ]
  2. Yuan JP, Wang JH, Liu X: Metabolism of dietary soy isoflavones to equol by human intestinal microflora--implications for health. Mol Nutr Food Res. 2007 Jul;51(7):765-81. [17579894 ]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

General Function:
Zinc ion binding
Specific Function:
Nuclear hormone receptor. The steroid hormones and their receptors are involved in the regulation of eukaryotic gene expression and affect cellular proliferation and differentiation in target tissues. Ligand-dependent nuclear transactivation involves either direct homodimer binding to a palindromic estrogen response element (ERE) sequence or association with other DNA-binding transcription factors, such as AP-1/c-Jun, c-Fos, ATF-2, Sp1 and Sp3, to mediate ERE-independent signaling. Ligand binding induces a conformational change allowing subsequent or combinatorial association with multiprotein coactivator complexes through LXXLL motifs of their respective components. Mutual transrepression occurs between the estrogen receptor (ER) and NF-kappa-B in a cell-type specific manner. Decreases NF-kappa-B DNA-binding activity and inhibits NF-kappa-B-mediated transcription from the IL6 promoter and displace RELA/p65 and associated coregulators from the promoter. Recruited to the NF-kappa-B response element of the CCL2 and IL8 promoters and can displace CREBBP. Present with NF-kappa-B components RELA/p65 and NFKB1/p50 on ERE sequences. Can also act synergistically with NF-kappa-B to activate transcription involving respective recruitment adjacent response elements; the function involves CREBBP. Can activate the transcriptional activity of TFF1. Also mediates membrane-initiated estrogen signaling involving various kinase cascades. Isoform 3 is involved in activation of NOS3 and endothelial nitric oxide production. Isoforms lacking one or several functional domains are thought to modulate transcriptional activity by competitive ligand or DNA binding and/or heterodimerization with the full length receptor. Essential for MTA1-mediated transcriptional regulation of BRCA1 and BCAS3. Isoform 3 can bind to ERE and inhibit isoform 1.
Gene Name:
ESR1
Uniprot ID:
P03372
Molecular Weight:
66215.45 Da
References
  1. Matsumura A, Ghosh A, Pope GS, Darbre PD: Comparative study of oestrogenic properties of eight phytoestrogens in MCF7 human breast cancer cells. J Steroid Biochem Mol Biol. 2005 Apr;94(5):431-43. Epub 2005 Mar 21. [15876408 ]
  2. Witters H, Freyberger A, Smits K, Vangenechten C, Lofink W, Weimer M, Bremer S, Ahr PH, Berckmans P: The assessment of estrogenic or anti-estrogenic activity of chemicals by the human stably transfected estrogen sensitive MELN cell line: results of test performance and transferability. Reprod Toxicol. 2010 Aug;30(1):60-72. doi: 10.1016/j.reprotox.2010.02.008. Epub 2010 Mar 31. [20362049 ]
  3. van der Burg B, Winter R, Weimer M, Berckmans P, Suzuki G, Gijsbers L, Jonas A, van der Linden S, Witters H, Aarts J, Legler J, Kopp-Schneider A, Bremer S: Optimization and prevalidation of the in vitro ERalpha CALUX method to test estrogenic and antiestrogenic activity of compounds. Reprod Toxicol. 2010 Aug;30(1):73-80. doi: 10.1016/j.reprotox.2010.04.007. Epub 2010 May 8. [20435135 ]
General Function:
Zinc ion binding
Specific Function:
Nuclear hormone receptor. Binds estrogens with an affinity similar to that of ESR1, and activates expression of reporter genes containing estrogen response elements (ERE) in an estrogen-dependent manner (PubMed:20074560). Isoform beta-cx lacks ligand binding ability and has no or only very low ere binding activity resulting in the loss of ligand-dependent transactivation ability. DNA-binding by ESR1 and ESR2 is rapidly lost at 37 degrees Celsius in the absence of ligand while in the presence of 17 beta-estradiol and 4-hydroxy-tamoxifen loss in DNA-binding at elevated temperature is more gradual.
Gene Name:
ESR2
Uniprot ID:
Q92731
Molecular Weight:
59215.765 Da
References
  1. Mueller SO, Simon S, Chae K, Metzler M, Korach KS: Phytoestrogens and their human metabolites show distinct agonistic and antagonistic properties on estrogen receptor alpha (ERalpha) and ERbeta in human cells. Toxicol Sci. 2004 Jul;80(1):14-25. Epub 2004 Apr 14. [15084758 ]