Butylparaben (T3D3980)

IdentificationTaxonomyBiological PropertiesPhysical PropertiesToxicity ProfileSpectraConcentrationsLinksReferencesGene RegulationTargets (7)XML
Targets (7)
Record Information
Version2.0
Creation Date2014-08-29 04:48:30 UTC
Update Date2014-12-24 20:26:35 UTC
Accession NumberT3D3980
Identification
Common NameButylparaben
ClassSmall Molecule
DescriptionButylparaben is a preservative and flavouring agent. Butylparaben has been shown to exhibit anti-microbial function Butylparaben belongs to the family of Hydroxybenzoic Acid Derivatives. These are compounds containing an hydroxybenzoic acid (or a derivative), which is a benzene ring bearing a carboxylic acid. (1).
Compound Type
  • Ester
  • Ether
  • Flavouring Agent
  • Food Toxin
  • Household Toxin
  • Industrial/Workplace Toxin
  • Metabolite
  • Organic Compound
  • Preservative
  • Synthetic Compound
Chemical Structure
Thumb
MOLSDFPDBSMILESInChI
Synonyms
Synonym
4-(Butoxycarbonyl)phenol
4-Hydroxybenzoic acid butyl ester
4-Hydroxybenzoic acid, butyl ester
Aseptoform butyl
Benzoic acid, 4-hydroxy-, butyl ester
Benzoic acid, p-hydroxy-, butyl ester
Butoben
Butyl //p//-hydroxybenzoate
Butyl 4-hydroxybenzoate
Butyl butex
Butyl chemosept
Butyl p-hydroxybenzoate
Butyl par asept
Butyl paraben
Butyl parahydroxybenzoate
Butyl parahydroxybenzoate (JP15)
Butyl parasept
Butyl tegosept
Butyl-p-hydroxybenzoate
Butyl-parasept
Butylparaben (NF)
FEMA 2203
Lexgard b
N-Butyl 4-hydroxybenzoate
N-Butyl hydroxybenzoate
N-Butyl p-hydroxybenzoate
N-Butyl paraben
N-Butyl parahydroxybenzoate
N-Butyl-4-hydroxybenzoate
N-Butyl-p-hydroxybenzoate
N-Butyl-paraben
Nipabutyl
P-Hydroxy butyl benzoate
P-Hydroxybenzoic acid butyl ester
P-Hydroxybenzoic acid N-butyl ester
P-Hydroxybenzoic acid, butyl ester
P-Hydroxybenzoic butyl ester
Parasept
Preserval b
Solbrol b
SPF
Tegosept B
Tegosept butyl
Chemical FormulaC11H14O3
Average Molecular Mass194.227 g/mol
Monoisotopic Mass194.094 g/mol
CAS Registry Number94-26-8
IUPAC Namebutyl 4-hydroxybenzoate
Traditional Namebutylparaben
SMILESCCCCOC(=O)C1=CC=C(O)C=C1
InChI IdentifierInChI=1S/C11H14O3/c1-2-3-8-14-11(13)9-4-6-10(12)7-5-9/h4-7,12H,2-3,8H2,1H3
InChI KeyInChIKey=QFOHBWFCKVYLES-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of organic compounds known as p-hydroxybenzoic acid alkyl esters. These are aromatic compounds containing a benzoic acid, which is esterified with an alkyl group and para-substituted with a hydroxyl group.
KingdomOrganic compounds
Super ClassBenzenoids
ClassBenzene and substituted derivatives
Sub ClassBenzoic acids and derivatives
Direct Parentp-Hydroxybenzoic acid alkyl esters
Alternative Parents
Substituents
  • P-hydroxybenzoic acid alkyl ester
  • Benzoyl
  • 1-hydroxy-2-unsubstituted benzenoid
  • Phenol
  • Carboxylic acid ester
  • Monocarboxylic acid or derivatives
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Aromatic homomonocyclic compound
Molecular FrameworkAromatic homomonocyclic compounds
External DescriptorsNot Available
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 Point68 - 69°C
Boiling PointNot Available
Solubility0.207 mg/mL at 20°C
LogP3.57
Predicted Properties
PropertyValueSource
Water Solubility0.47 g/LALOGPS
logP3.81ALOGPS
logP3ChemAxon
logS-2.6ALOGPS
pKa (Strongest Acidic)8.5ChemAxon
pKa (Strongest Basic)-6.1ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count2ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area46.53 ŲChemAxon
Rotatable Bond Count5ChemAxon
Refractivity53.94 m³·mol⁻¹ChemAxon
Polarizability21.45 ųChemAxon
Number of Rings1ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyDeposition DateView
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-00dr-2900000000-bb56a149a6da74d93ee82017-09-12View Spectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0079-3900000000-3c58d2a06f7053d6232c2017-09-12View Spectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-00dr-2900000000-bb56a149a6da74d93ee82018-05-18View Spectrum
GC-MSGC-MS Spectrum - EI-B (Non-derivatized)splash10-0079-3900000000-3c58d2a06f7053d6232c2018-05-18View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-00di-5900000000-a07eb5ffe2dd5224cc422017-09-01View Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-0006-4900000000-b50d93adc6a9e391c4672017-10-06View 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-ITFT , negativesplash10-0006-0900000000-e5adfc9cf6eccf247f8a2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-0006-0900000000-2b574dc259808331afc72017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-000i-1900000000-831ef1d350d13780a3292017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-000i-1900000000-ce6d6917117d7a334d952017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QFT , negativesplash10-0006-0900000000-56813e9a5bacca3c57f92017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-0006-0900000000-e5adfc9cf6eccf247f8a2017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-0006-0900000000-2b574dc259808331afc72017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-000i-1900000000-831ef1d350d13780a3292017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , negativesplash10-000i-1900000000-ce6d6917117d7a334d952017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0072-9800000000-fe4706758a9d399987b92017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-001i-9500000000-8c7830a4583c649d27532017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-000i-0900000000-4981588a915a613086d02017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-000i-0900000000-a1bc78b908d3b7a1fb172017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-0072-9800000000-fe4706758a9d399987b92017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-001i-9500000000-8c7830a4583c649d27532017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-000i-0900000000-4981588a915a613086d02017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-ITFT , positivesplash10-000i-0900000000-a1bc78b908d3b7a1fb172017-09-14View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 30V, Positivesplash10-00dr-0900000000-ec37bfdb07ea8c0fc84a2021-09-20View Spectrum
LC-MS/MSLC-MS/MS Spectrum - 40V, Positivesplash10-00di-0900000000-163529e9ff8dd2665de22021-09-20View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-0002-2900000000-5c2e16e5df0c1640445a2015-04-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0ab9-9600000000-d8a6a3f37504b01c37732015-04-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0abc-9200000000-df6492b55ad6172bd44f2015-04-24View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0006-1900000000-aec24ddd4de8f43b0a062015-04-25View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-000f-3900000000-ef4eb95372bf56bcd2942015-04-25View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-00kf-9400000000-34d1624c244b2672ad382015-04-25View Spectrum
MSMass Spectrum (Electron Ionization)splash10-00dr-3900000000-0366956a08d3509a13f72014-09-20View Spectrum
1D NMR1H NMR Spectrum (1D, 90 MHz, CDCl3, experimental)Not Available2014-09-20View Spectrum
1D NMR13C NMR Spectrum (1D, 25.16 MHz, CDCl3, experimental)Not Available2014-09-23View 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/SourcesNot Available
Minimum Risk LevelNot Available
Health EffectsNot Available
SymptomsNot Available
TreatmentNot Available
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDHMDB32575
PubChem Compound ID7184
ChEMBL IDCHEMBL459008
ChemSpider ID6916
KEGG IDNot Available
UniProt IDNot Available
OMIM ID
ChEBI IDNot Available
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkNot Available
References
Synthesis ReferenceNot Available
MSDST3D3980.pdf
General References
  1. Qian L, Guan Y, Xiao H: Preparation and characterization of inclusion complexes of a cationic beta-cyclodextrin polymer with butylparaben or triclosan. Int J Pharm. 2008 Jun 5;357(1-2):244-51. doi: 10.1016/j.ijpharm.2008.01.018. Epub 2008 Jan 19. [18294789 ]
  2. Yannai, Shmuel. (2004) Dictionary of food compounds with CD-ROM: Additives, flavors, and ingredients. Boca Raton: Chapman & Hall/CRC.
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

Target Details
1. Estrogen receptor
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
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC503.50 uMACEA_T47D_80hr_PositiveACEA Biosciences
AC501.27 uMNVS_NR_hERNovascreen
AC505.05 uMTox21_ERa_LUC_BG1_AgonistTox21/NCGC
References
  1. 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 ]
  2. 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 ]
  3. Watanabe Y, Kojima H, Takeuchi S, Uramaru N, Ohta S, Kitamura S: Comparative study on transcriptional activity of 17 parabens mediated by estrogen receptor alpha and beta and androgen receptor. Food Chem Toxicol. 2013 Jul;57:227-34. doi: 10.1016/j.fct.2013.03.036. Epub 2013 Apr 6. [23567241 ]
  4. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
Target Details
2. Estrogen receptor beta
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
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC504.05 uMOT_ER_ERaERb_0480Odyssey Thera
AC504.59 uMOT_ER_ERbERb_0480Odyssey Thera
AC505.66 uMOT_ER_ERbERb_1440Odyssey Thera
References
  1. Watanabe Y, Kojima H, Takeuchi S, Uramaru N, Ohta S, Kitamura S: Comparative study on transcriptional activity of 17 parabens mediated by estrogen receptor alpha and beta and androgen receptor. Food Chem Toxicol. 2013 Jul;57:227-34. doi: 10.1016/j.fct.2013.03.036. Epub 2013 Apr 6. [23567241 ]
  2. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
Target Details
3. Peroxisome proliferator-activated receptor gamma
General Function:
Zinc ion binding
Specific Function:
Nuclear receptor that binds peroxisome proliferators such as hypolipidemic drugs and fatty acids. Once activated by a ligand, the nuclear receptor binds to DNA specific PPAR response elements (PPRE) and modulates the transcription of its target genes, such as acyl-CoA oxidase. It therefore controls the peroxisomal beta-oxidation pathway of fatty acids. Key regulator of adipocyte differentiation and glucose homeostasis. ARF6 acts as a key regulator of the tissue-specific adipocyte P2 (aP2) enhancer. Acts as a critical regulator of gut homeostasis by suppressing NF-kappa-B-mediated proinflammatory responses. Plays a role in the regulation of cardiovascular circadian rhythms by regulating the transcription of ARNTL/BMAL1 in the blood vessels (By similarity).
Gene Name:
PPARG
Uniprot ID:
P37231
Molecular Weight:
57619.58 Da
References
  1. Pereira-Fernandes A, Demaegdt H, Vandermeiren K, Hectors TL, Jorens PG, Blust R, Vanparys C: Evaluation of a screening system for obesogenic compounds: screening of endocrine disrupting compounds and evaluation of the PPAR dependency of the effect. PLoS One. 2013 Oct 14;8(10):e77481. doi: 10.1371/journal.pone.0077481. eCollection 2013. [24155963 ]
Target Details
4. Cytochrome P450 1A2
General Function:
Oxidoreductase activity, acting on paired donors, with incorporation or reduction of molecular oxygen, reduced flavin or flavoprotein as one donor, and incorporation of one atom of oxygen
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Most active in catalyzing 2-hydroxylation. Caffeine is metabolized primarily by cytochrome CYP1A2 in the liver through an initial N3-demethylation. Also acts in the metabolism of aflatoxin B1 and acetaminophen. Participates in the bioactivation of carcinogenic aromatic and heterocyclic amines. Catalizes the N-hydroxylation of heterocyclic amines and the O-deethylation of phenacetin.
Gene Name:
CYP1A2
Uniprot ID:
P05177
Molecular Weight:
58293.76 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC501.37 uMNVS_ADME_hCYP1A2Novascreen
References
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
Target Details
5. Cytochrome P450 2B6
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. Acts as a 1,4-cineole 2-exo-monooxygenase.
Gene Name:
CYP2B6
Uniprot ID:
P20813
Molecular Weight:
56277.81 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC503.64 uMNVS_ADME_hCYP2B6Novascreen
References
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
Target Details
6. Cytochrome P450 2C9
General Function:
Steroid hydroxylase activity
Specific Function:
Cytochromes P450 are a group of heme-thiolate monooxygenases. In liver microsomes, this enzyme is involved in an NADPH-dependent electron transport pathway. It oxidizes a variety of structurally unrelated compounds, including steroids, fatty acids, and xenobiotics. This enzyme contributes to the wide pharmacokinetics variability of the metabolism of drugs such as S-warfarin, diclofenac, phenytoin, tolbutamide and losartan.
Gene Name:
CYP2C9
Uniprot ID:
P11712
Molecular Weight:
55627.365 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC505.40 uMNVS_ADME_hCYP2C9Novascreen
References
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]
Target Details
7. Cytochrome P450 2C19
General Function:
Steroid hydroxylase activity
Specific Function:
Responsible for the metabolism of a number of therapeutic agents such as the anticonvulsant drug S-mephenytoin, omeprazole, proguanil, certain barbiturates, diazepam, propranolol, citalopram and imipramine.
Gene Name:
CYP2C19
Uniprot ID:
P33261
Molecular Weight:
55930.545 Da
Binding/Activity Constants
TypeValueAssay TypeAssay Source
AC505.99 uMNVS_ADME_hCYP2C19Novascreen
References
  1. Sipes NS, Martin MT, Kothiya P, Reif DM, Judson RS, Richard AM, Houck KA, Dix DJ, Kavlock RJ, Knudsen TB: Profiling 976 ToxCast chemicals across 331 enzymatic and receptor signaling assays. Chem Res Toxicol. 2013 Jun 17;26(6):878-95. doi: 10.1021/tx400021f. Epub 2013 May 16. [23611293 ]