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Equilin

PubChem CID
223368
Structure
Equilin_small.png
Equilin_3D_Structure.png
Equilin__Crystal_Structure.png
Molecular Formula
Synonyms
  • equilin
  • 474-86-2
  • 7-Dehydroestrone
  • Dihydroequilenin
  • 3-HYDROXYESTRA-1,3,5(10),7-TETRAEN-17-ONE
Molecular Weight
268.3 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Dates
  • Create:
    2005-03-26
  • Modify:
    2025-01-25
Description
Equilin is a 17-oxo steroid and a 3-hydroxy steroid. It derives from a hydride of an estrane.
An estrogenic steroid produced by horses. It has a total of four double bonds in the A- and B-ring. High concentration of equilin is found in the urine of pregnant mares.
Equilin is a naturally occurring steroid with estrogenic activity obtained from the urine of pregnant mares.

1 Structures

1.1 2D Structure

Chemical Structure Depiction
Equilin.png

1.2 3D Conformer

1.3 Crystal Structures

1 of 2
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CCDC Number
Crystal Structure Data
Crystal Structure Depiction
Crystal Structure Depiction

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

(9S,13S,14S)-3-hydroxy-13-methyl-9,11,12,14,15,16-hexahydro-6H-cyclopenta[a]phenanthren-17-one
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/C18H20O2/c1-18-9-8-14-13-5-3-12(19)10-11(13)2-4-15(14)16(18)6-7-17(18)20/h3-5,10,14,16,19H,2,6-9H2,1H3/t14-,16+,18+/m1/s1
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

WKRLQDKEXYKHJB-HFTRVMKXSA-N
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.4 SMILES

C[C@]12CC[C@H]3C(=CCC4=C3C=CC(=C4)O)[C@@H]1CCC2=O
Computed by OEChem 2.3.0 (PubChem release 2024.12.12)

2.2 Molecular Formula

C18H20O2
Computed by PubChem 2.2 (PubChem release 2021.10.14)

2.3 Other Identifiers

2.3.1 CAS

2.3.2 European Community (EC) Number

2.3.3 UNII

2.3.4 ChEBI ID

2.3.5 ChEMBL ID

2.3.6 DrugBank ID

2.3.7 DSSTox Substance ID

2.3.8 KEGG ID

2.3.9 Lipid Maps ID (LM_ID)

2.3.10 Metabolomics Workbench ID

2.3.11 NCI Thesaurus Code

2.3.12 Nikkaji Number

2.3.13 NSC Number

2.3.14 Pharos Ligand ID

2.3.15 Wikidata

2.3.16 Wikipedia

2.4 Synonyms

2.4.1 MeSH Entry Terms

Equilin

2.4.2 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
268.3 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
XLogP3-AA
Property Value
2.9
Reference
Computed by XLogP3 3.0 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Donor Count
Property Value
1
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Acceptor Count
Property Value
2
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Rotatable Bond Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
268.146329876 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
268.146329876 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
37.3 Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
20
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
466
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Isotope Atom Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Atom Stereocenter Count
Property Value
3
Reference
Computed by PubChem
Property Name
Undefined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Covalently-Bonded Unit Count
Property Value
1
Reference
Computed by PubChem
Property Name
Compound Is Canonicalized
Property Value
Yes
Reference
Computed by PubChem (release 2021.10.14)

3.2 Experimental Properties

3.2.1 Melting Point

239 °C
PhysProp

3.2.2 Solubility

1.41 mg/L (at 25 °C)
YALKOWSKY,SH & DANNENFELSER,RM (1992)

3.2.3 Collision Cross Section

153.17 Ų [M+H-H2O]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

160.72 Ų [M+Na]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

157.92 Ų [M+H]+ [CCS Type: TW; Method: calibrated with polyalanine and drug standards]

Ross et al. JASMS 2022; 33; 1061-1072. DOI:10.1021/jasms.2c00111

3.2.4 Kovats Retention Index

Standard non-polar
2745.3 , 2765.4 , 2766.1

3.3 SpringerMaterials Properties

3.4 Chemical Classes

Hormone

3.4.1 Drugs

Pharmaceuticals -> Listed in ZINC15
S55 | ZINC15PHARMA | Pharmaceuticals from ZINC15 | DOI:10.5281/zenodo.3247749

3.4.2 Endocrine Disruptors

Potential endocrine disrupting compound
S109 | PARCEDC | List of 7074 potential endocrine disrupting compounds (EDCs) by PARC T4.2 | DOI:10.5281/zenodo.10944198

3.4.3 Lipids

Lipids -> Sterol Lipids [ST] -> Steroids [ST02] -> C18 steroids (estrogens) and derivatives [ST0201]

4 Spectral Information

4.1 1D NMR Spectra

4.1.1 1H NMR Spectra

Instrument Name
Varian CFT-20
Copyright
Copyright © 2009-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.2 Mass Spectrometry

4.2.1 GC-MS

1 of 6
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NIST Number
79063
Library
Main library
Total Peaks
158
m/z Top Peak
268
m/z 2nd Highest
144
m/z 3rd Highest
157
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2 of 6
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NIST Number
12988
Library
Replicate library
Total Peaks
134
m/z Top Peak
268
m/z 2nd Highest
144
m/z 3rd Highest
157
Thumbnail
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4.2.2 LC-MS

1 of 3
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MS Category
Experimental
MS Type
LC-MS
MS Level
MS2
Precursor Type
[M+NH4]+
Precursor m/z
286.1801452636719
Instrument
Thermo Q Exactive HF
Instrument Type
ESI-QFT
Ionization Mode
positive
Collision Energy
65HCD
Top 5 Peaks

56.965034 100

152.989216 50.50

70.065175 49.14

57.070130 47.23

88.075668 38.24

Thumbnail
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2 of 3
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MS Category
Experimental
MS Type
LC-MS
MS Level
MS2
Precursor Type
[M+NH4]+
Precursor m/z
286.1801452636719
Instrument
Thermo Q Exactive HF
Instrument Type
ESI-QFT
Ionization Mode
positive
Collision Energy
45HCD
Top 5 Peaks

288.289394 100

152.989202 82.51

106.086262 70.10

88.075686 60.52

134.978608 53.84

Thumbnail
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4.2.3 Other MS

1 of 2
MS Category
Experimental
MS Type
Other
MS Level
MS2
Precursor Type
[M-H]-
Precursor m/z
267.1390534
Ionization Mode
negative
Retention Time
4.467535823
Top 5 Peaks

265.122057 0.75

239.112488 0.14

237.126666 0.03

181.122772 0.03

251.108781 0.02

Thumbnail
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2 of 2
MoNA ID
MS Category
Experimental
MS Type
Other
Precursor Type
[M+H]+
Top 5 Peaks

148.1130533158636 9.94

160.08436131586362 9.53

95.04771131586361 9.53

132.0179473158636 9.43

186.0998223158636 9.43

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4.3 IR Spectra

4.3.1 FTIR Spectra

1 of 2
Technique
KBr WAFER
Source of Sample
Unknown
Copyright
Copyright © 1980, 1981-2024 John Wiley & Sons, Inc. All Rights Reserved.
Thumbnail
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2 of 2
Instrument Name
Bio-Rad FTS
Technique
KBr1 0.49mg
Source of Spectrum
Forensic Spectral Research
Source of Sample
Steraloids
Catalog Number
E0600-000
Lot Number
G779
Copyright
Copyright © 2008-2024 John Wiley & Sons, Inc. All Rights Reserved.
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4.3.2 ATR-IR Spectra

Instrument Name
Bio-Rad FTS
Technique
ATR-Neat (DuraSamplIR II) ground
Source of Spectrum
Forensic Spectral Research
Source of Sample
Steraloids Inc.
Catalog Number
E0600-000
Lot Number
G779
Copyright
Copyright © 2009-2024 John Wiley & Sons, Inc. All Rights Reserved.
Thumbnail
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4.4 Raman Spectra

Technique
FT-Raman
Source of Spectrum
Forensic Spectral Research
Source of Sample
Steraloids Inc.
Catalog Number
E0600-000
Lot Number
G779
Copyright
Copyright © 2013-2024 John Wiley & Sons, Inc. All Rights Reserved.
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6 Chemical Vendors

7 Drug and Medication Information

7.1 Drug Indication

For the treatment of moderate to severe vasomotor symptoms associated with the menopause, atrophic vaginitis, osteoporosis, hypoestrogenism due to hypogonadism, castration, primary ovarian failure, breast cancer (for palliation only), and Advanced androgen-dependent carcinoma of the prostate (for palliation only)

8 Pharmacology and Biochemistry

8.1 Pharmacodynamics

Equilin is a component of Premarin (conjugated estrogens), a mixture of the water soluble salts of sulfate esters from estrone, equilin, 17 alpha-dihydroequilin, and other related steroids, may be derived from pregnant equine urine or yam and soy plants. Estrogens are important in the development and maintenance of the female reproductive system and secondary sex characteristics. They promote growth and development of the vagina, uterus, and fallopian tubes, and enlargement of the breasts. Indirectly, they contribute to the shaping of the skeleton, maintenance of tone and elasticity of urogenital structures, changes in the epiphyses of the long bones that allow for the pubertal growth spurt and its termination, growth of axillary and pubic hair, and pigmentation of the nipples and genitals. Decline of estrogenic activity at the end of the menstrual cycle can bring on menstruation, although the cessation of progesterone secretion is the most important factor in the mature ovulatory cycle. However, in the preovulatory or nonovulatory cycle, estrogen is the primary determinant in the onset of menstruation. Estrogens also affect the release of pituitary gonadotropins. The pharmacologic effects of conjugated estrogens are similar to those of endogenous estrogens.

8.2 Absorption, Distribution and Excretion

Absorption
Well absorbed.

8.3 Metabolism / Metabolites

Hepatic
Hepatic.

8.4 Mechanism of Action

Estrogens enter the cells of responsive tissues (e.g., female organs, breasts, hypothalamus, pituitary) where they interact with a protein receptor, subsequently increasing the rate of synthesis of DNA, RNA, and some proteins. Estrogens decrease the secretion of gonadotropin-releasing hormone by the hypothalamus, reducing the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary.

9 Use and Manufacturing

9.1 Uses

For the treatment of moderate to severe vasomotor symptoms associated with the menopause, atrophic vaginitis, osteoporosis, hypoestrogenism due to hypogonadism, castration, primary ovarian failure, breast cancer (for palliation only), and Advanced androgen-dependent carcinoma of the prostate (for palliation only)

10 Safety and Hazards

10.1 Hazards Identification

10.1.1 GHS Classification

Pictogram(s)
Irritant
Health Hazard
Signal
Danger
GHS Hazard Statements

H302 (20.7%): Harmful if swallowed [Warning Acute toxicity, oral]

H312 (20.7%): Harmful in contact with skin [Warning Acute toxicity, dermal]

H332 (20.7%): Harmful if inhaled [Warning Acute toxicity, inhalation]

H351 (98.8%): Suspected of causing cancer [Warning Carcinogenicity]

H360 (32.9%): May damage fertility or the unborn child [Danger Reproductive toxicity]

H361 (67.1%): Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

H362 (31.7%): May cause harm to breast-fed children [Reproductive toxicity, effects on or via lactation]

Precautionary Statement Codes

P203, P260, P261, P263, P264, P270, P271, P280, P301+P317, P302+P352, P304+P340, P317, P318, P321, P330, P362+P364, P405, and P501

(The corresponding statement to each P-code can be found at the GHS Classification page.)

ECHA C&L Notifications Summary

Aggregated GHS information provided per 82 reports by companies from 5 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown.

10.1.2 Hazard Classes and Categories

Acute Tox. 4 (20.7%)

Acute Tox. 4 (20.7%)

Acute Tox. 4 (20.7%)

Carc. 2 (98.8%)

Repr. 1A (32.9%)

Repr. 2 (67.1%)

Lact. (31.7%)

11 Toxicity

11.1 Toxicological Information

11.1.1 Toxicity Summary

Estrogens enter the cells of responsive tissues (e.g., female organs, breasts, hypothalamus, pituitary) where they interact with a protein receptor, subsequently increasing the rate of synthesis of DNA, RNA, and some proteins. Estrogens decrease the secretion of gonadotropin-releasing hormone by the hypothalamus, reducing the secretion of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the pituitary.

11.1.2 USGS Health-Based Screening Levels for Evaluating Water-Quality

Chemical
Equilin
Chemical Classes
Hormone
Reference
Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

11.1.3 Carcinogen Classification

Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).

11.1.4 Exposure Routes

Well absorbed.

11.1.5 Protein Binding

90% bound to plasma proteins

12 Associated Disorders and Diseases

13 Literature

13.1 Consolidated References

13.2 NLM Curated PubMed Citations

13.3 Springer Nature References

13.4 Thieme References

13.5 Chemical Co-Occurrences in Literature

13.6 Chemical-Gene Co-Occurrences in Literature

13.7 Chemical-Disease Co-Occurrences in Literature

14 Patents

14.1 Depositor-Supplied Patent Identifiers

14.2 WIPO PATENTSCOPE

14.3 Chemical Co-Occurrences in Patents

14.4 Chemical-Disease Co-Occurrences in Patents

14.5 Chemical-Gene Co-Occurrences in Patents

15 Interactions and Pathways

15.1 Protein Bound 3D Structures

15.1.1 Ligands from Protein Bound 3D Structures

PDBe Ligand Code
PDBe Structure Code
PDBe Conformer

15.2 Chemical-Target Interactions

15.3 Drug-Drug Interactions

16 Biological Test Results

16.1 BioAssay Results

17 Classification

17.1 MeSH Tree

17.2 NCI Thesaurus Tree

17.3 ChEBI Ontology

17.4 LIPID MAPS Classification

17.5 KEGG: Metabolite

17.6 KEGG: Lipid

17.7 KEGG: Target-based Classification of Drugs

17.8 KEGG: Drug Groups

17.9 ChemIDplus

17.10 ChEMBL Target Tree

17.11 UN GHS Classification

17.12 NORMAN Suspect List Exchange Classification

17.13 CCSBase Classification

17.14 EPA DSSTox Classification

17.15 EPA Substance Registry Services Tree

17.16 MolGenie Organic Chemistry Ontology

18 Information Sources

  1. CAS Common Chemistry
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    https://creativecommons.org/licenses/by-nc/4.0/
  2. ChemIDplus
    ChemIDplus Chemical Information Classification
    https://pubchem.ncbi.nlm.nih.gov/source/ChemIDplus
  3. DrugBank
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    https://www.drugbank.ca/legal/terms_of_use
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    https://www.cancer.gov/policies/copyright-reuse
  5. EPA DSSTox
    CompTox Chemicals Dashboard Chemical Lists
    https://comptox.epa.gov/dashboard/chemical-lists/
  6. European Chemicals Agency (ECHA)
    LICENSE
    Use of the information, documents and data from the ECHA website is subject to the terms and conditions of this Legal Notice, and subject to other binding limitations provided for under applicable law, the information, documents and data made available on the ECHA website may be reproduced, distributed and/or used, totally or in part, for non-commercial purposes provided that ECHA is acknowledged as the source: "Source: European Chemicals Agency, http://echa.europa.eu/". Such acknowledgement must be included in each copy of the material. ECHA permits and encourages organisations and individuals to create links to the ECHA website under the following cumulative conditions: Links can only be made to webpages that provide a link to the Legal Notice page.
    https://echa.europa.eu/web/guest/legal-notice
  7. FDA Global Substance Registration System (GSRS)
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    https://www.fda.gov/about-fda/about-website/website-policies#linking
  8. CCSbase
    CCSbase Classification
    https://ccsbase.net/
  9. ChEBI
  10. NCI Thesaurus (NCIt)
    LICENSE
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    https://www.cancer.gov/policies/copyright-reuse
  11. Toxin and Toxin Target Database (T3DB)
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    http://www.t3db.ca/downloads
  12. ChEMBL
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    http://www.ebi.ac.uk/Information/termsofuse.html
  13. Comparative Toxicogenomics Database (CTD)
    LICENSE
    It is to be used only for research and educational purposes. Any reproduction or use for commercial purpose is prohibited without the prior express written permission of NC State University.
    http://ctdbase.org/about/legal.jsp
  14. Drug Gene Interaction database (DGIdb)
    LICENSE
    The data used in DGIdb is all open access and where possible made available as raw data dumps in the downloads section.
    http://www.dgidb.org/downloads
  15. Therapeutic Target Database (TTD)
  16. Crystallography Open Database (COD)
    LICENSE
    All data in the COD and the database itself are dedicated to the public domain and licensed under the CC0 License. Users of the data should acknowledge the original authors of the structural data.
    https://creativecommons.org/publicdomain/zero/1.0/
  17. The Cambridge Structural Database
  18. Japan Chemical Substance Dictionary (Nikkaji)
  19. KEGG
    LICENSE
    Academic users may freely use the KEGG website. Non-academic use of KEGG generally requires a commercial license
    https://www.kegg.jp/kegg/legal.html
    Target-based classification of drugs
    http://www.genome.jp/kegg-bin/get_htext?br08310.keg
  20. LIPID MAPS
    Lipid Classification
    https://www.lipidmaps.org/
  21. MassBank of North America (MoNA)
    LICENSE
    The content of the MoNA database is licensed under CC BY 4.0.
    https://mona.fiehnlab.ucdavis.edu/documentation/license
  22. Metabolomics Workbench
  23. NIST Mass Spectrometry Data Center
    LICENSE
    Data covered by the Standard Reference Data Act of 1968 as amended.
    https://www.nist.gov/srd/public-law
  24. SpectraBase
    ESTRA-1,3,5(10),7-TETRAENE-3-OL-17-ONE
    https://spectrabase.com/spectrum/Hm0TF5r4MTX
  25. NORMAN Suspect List Exchange
    LICENSE
    Data: CC-BY 4.0; Code (hosted by ECI, LCSB): Artistic-2.0
    https://creativecommons.org/licenses/by/4.0/
    Equilin
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  26. Pharos
    LICENSE
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    https://pharos.nih.gov/about
  27. Protein Data Bank in Europe (PDBe)
  28. RCSB Protein Data Bank (RCSB PDB)
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    https://www.rcsb.org/pages/policies
  29. Springer Nature
  30. SpringerMaterials
  31. Thieme Chemistry
    LICENSE
    The Thieme Chemistry contribution within PubChem is provided under a CC-BY-NC-ND 4.0 license, unless otherwise stated.
    https://creativecommons.org/licenses/by-nc-nd/4.0/
  32. USGS Health-Based Screening Levels for Evaluating Water-Quality Data
  33. Wikidata
  34. Wikipedia
  35. Medical Subject Headings (MeSH)
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    https://www.nlm.nih.gov/copyright.html
  36. PubChem
  37. GHS Classification (UNECE)
  38. EPA Substance Registry Services
  39. MolGenie
    MolGenie Organic Chemistry Ontology
    https://github.com/MolGenie/ontology/
  40. PATENTSCOPE (WIPO)
CONTENTS