An official website of the United States government

DL-Goitrin

PubChem CID
3034683
Structure
DL-Goitrin_small.png
DL-Goitrin_3D_Structure.png
Molecular Formula
Synonyms
  • DL-Goitrin
  • Goitrin
  • 13190-34-6
  • 2-Oxazolidinethione, 5-ethenyl-
  • 5-Vinyloxazolidine-2-thione
Molecular Weight
129.18 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Dates
  • Create:
    2005-03-27
  • Modify:
    2025-01-18
Description
5-ethenyl-1,3-oxazolidine-2-thione is a member of the class of oxazolidines that is 1,3-oxazolidine substituted by sulfanylidene and ethenyl groups at positions 2 and 5, respectively. It is a member of oxazolidines and an olefinic compound.
DL-Goitrin has been reported in Isatis tinctoria with data available.

1 Structures

1.1 2D Structure

Chemical Structure Depiction
DL-Goitrin.png

1.2 3D Conformer

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

5-ethenyl-1,3-oxazolidine-2-thione
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/C5H7NOS/c1-2-4-3-6-5(8)7-4/h2,4H,1,3H2,(H,6,8)
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

UZQVYLOFLQICCT-UHFFFAOYSA-N
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.4 SMILES

C=CC1CNC(=S)O1
Computed by OEChem 2.3.0 (PubChem release 2024.12.12)

2.2 Molecular Formula

C5H7NOS
Computed by PubChem 2.2 (PubChem release 2021.10.14)

2.3 Other Identifiers

2.3.1 CAS

13997-13-2
500-12-9

2.3.3 European Community (EC) Number

2.3.4 UNII

2.3.5 ChEBI ID

2.3.6 ChEMBL ID

2.3.7 DSSTox Substance ID

2.3.8 HMDB ID

2.3.9 Nikkaji Number

2.3.10 Wikidata

2.3.11 Wikipedia

2.4 Synonyms

2.4.1 MeSH Entry Terms

  • 5-vinyl-2-thiooxazolidone
  • 5-vinyloxazolidin-2-thione
  • 5-vinyloxazolidine-2-thione
  • epigoitrin
  • goitrin
  • goitrin, (+-)-isomer
  • goitrin, (R)-isomer
  • goitrin, (S)-isomer

2.4.2 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
129.18 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
XLogP3-AA
Property Value
1
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
1
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
129.02483502 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
129.02483502 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
53.4 Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
8
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
124
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
0
Reference
Computed by PubChem
Property Name
Undefined Atom Stereocenter Count
Property Value
1
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 Physical Description

Solid; [Merck Index]

3.2.2 Color / Form

Large prisms from ether
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

3.2.3 Melting Point

50 °C
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

3.2.4 Stability / Shelf Life

Stable in alkali, but not in acid.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

3.2.5 Optical Rotation

Specific optical rotation at 31 °C for D (sodium) line = -70.5 deg (c=2 in methanol).
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

3.2.6 Dissociation Constants

pKa = 10.5
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

3.3 Chemical Classes

Biological Agents -> Plant Toxins

4 Spectral Information

4.1 Mass Spectrometry

4.1.1 GC-MS

1 of 5
View All
NIST Number
136081
Library
Main library
Total Peaks
57
m/z Top Peak
129
m/z 2nd Highest
68
m/z 3rd Highest
39
Thumbnail
Thumbnail
2 of 5
View All
NIST Number
196284
Library
Main library
Total Peaks
71
m/z Top Peak
129
m/z 2nd Highest
68
m/z 3rd Highest
57
Thumbnail
Thumbnail

4.1.2 LC-MS

1 of 23
View All
Authors
Tobias Schulze, Martin Krauss, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany
Instrument
LTQ Orbitrap XL Thermo Scientific
Instrument Type
LC-ESI-ITFT
MS Level
MS2
Ionization Mode
POSITIVE
Ionization
ESI
Collision Energy
10% (nominal)
Fragmentation Mode
HCD
Column Name
Kinetex Evo C18 2.6 um 50x2.1 mm, Phenomenex
Retention Time
1.217 min
Precursor m/z
130.0321
Precursor Adduct
[M+H]+
Top 5 Peaks

130.032 999

70.0649 403

Thumbnail
Thumbnail
License
CC0
2 of 23
View All
Authors
Tobias Schulze, Martin Krauss, Helmholtz Centre for Environmental Research GmbH - UFZ, Leipzig, Germany
Instrument
LTQ Orbitrap XL Thermo Scientific
Instrument Type
LC-ESI-ITFT
MS Level
MS2
Ionization Mode
POSITIVE
Ionization
ESI
Collision Energy
15% (nominal)
Fragmentation Mode
HCD
Column Name
Kinetex Evo C18 2.6 um 50x2.1 mm, Phenomenex
Retention Time
1.217 min
Precursor m/z
130.0321
Precursor Adduct
[M+H]+
Top 5 Peaks

130.032 999

70.0648 526

Thumbnail
Thumbnail
License
CC0

4.1.3 Other MS

1 of 3
View All
Authors
EPA CCTE and Agilent Technologies
Instrument Type
ESI-QTOF
MS Level
MS2
Ionization Mode
NEGATIVE
Ionization
ESI
Collision Energy
20
Precursor m/z
128.0175581
Precursor Adduct
[M-H]-
Top 5 Peaks

57.975693 999

71.991343 136

Thumbnail
Thumbnail
License
CC BY
2 of 3
View All
Authors
EPA CCTE and Agilent Technologies
Instrument Type
ESI-QTOF
MS Level
MS2
Ionization Mode
NEGATIVE
Ionization
ESI
Collision Energy
40
Precursor m/z
128.0175581
Precursor Adduct
[M-H]-
Top 5 Peaks

57.975693 999

71.991343 50

Thumbnail
Thumbnail
License
CC BY

6 Chemical Vendors

7 Pharmacology and Biochemistry

7.1 MeSH Pharmacological Classification

Antithyroid Agents
Agents that are used to treat hyperthyroidism by reducing the excessive production of thyroid hormones. (See all compounds classified as Antithyroid Agents.)

7.2 Absorption, Distribution and Excretion

A total of six cows, divided into 3 groups, were fed various amounts of rape cake containing 6 g of goitrin/kg over a period of 7 days. The cows were milked twice a day ... . When rape cake was fed at 0.39, 1.9 and 3.9% resp. of the total feed this resulted in medium goitrin values of 37, 163 and 707 ug/l milk. These values correspond to a transfer of about 0.1% of the original progoitrin content in the feed. 12 h after the last rape feeding the amount of goitrin in the milk was below the detection limit of 7 ppb.

7.3 Mechanism of Action

A wide variety of chemicals, drugs, and other xenobiotics affect the second step in thyroid hormone biosynthesis. The stepwise binding of iodide to the tyrosyl residues in thyroglobulin requires oxidation of inorganic iodide (I2) to molecular (reactive) iodine (I2) by the thyroid peroxidase present in the luminal aspect (microvillar membranes) of follicular cells and adjacent colloid. Classes of chemicals that inhibit the organification of thyroglobulin include ... the thionamides (such as ... goitrin)... .
Klaassen, C.D. (ed). Casarett and Doull's Toxicology. The Basic Science of Poisons. 6th ed. New York, NY: McGraw-Hill, 2001., p. 726

8 Use and Manufacturing

8.1 Uses

Sources/Uses
A thyroid toxin found in the seeds of various Brassica and Cruciferae species; [Merck Index]
Merck Index - O'Neil MJ, Heckelman PE, Dobbelaar PH, Roman KJ (eds). The Merck Index, An Encyclopedia of Chemicals, Drugs, and Biologicals, 15th Ed. Cambridge, UK: The Royal Society of Chemistry, 2013.

8.2 General Manufacturing Information

An antithyroid cmpd isolated from seeds of different species of Brassica, Cruciferae: Astwood et al., J. Biol. Chem. 181,121 (1949); Greer, J. Am. Chem. Soc., 78, 1260 (1956)
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 804

9 Toxicity

9.1 Toxicological Information

9.1.1 Interactions

Goitrin is a potent goitrogen that has been shown to induce glutathione S-transferase (GST) activity and to increase aflatoxin detoxification.
Kelly M et al; Food and Chemical Toxicology 33(2): 129-137 (1995)
goitrin --a naturally occurring compound in cruciferous vegetables and rape--could be easily nitrosated by treatment with nitrite under stomach conditions, yielding with loss of sulfur the N-nitroso- oxazolidone 4. This product has a mutagenicity pattern and potency similar to that of N-nitroso-N-methyl-N'- nitroguanidine (MNNG) in the Ames Salmonella/mammalian microsome test.
Luthy J et al; Experientia 40(5): 452-453 (1984)

9.1.2 Antidote and Emergency Treatment

Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 ml/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Cover skin burns with dry sterile dressings after decontamination ... . /Poison A and B/
Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994., p. 139
Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Poison A and B/
Bronstein, A.C., P.L. Currance; Emergency Care for Hazardous Materials Exposure. 2nd ed. St. Louis, MO. Mosby Lifeline. 1994., p. 139

9.1.3 Non-Human Toxicity Excerpts

/LABORATORY ANIMALS: Acute Exposure/ Antithyroid activity of orally administered goitrin was assessed by parallel-line assay in chicks using four indices. The relative potency of goitrin in chicks was estimated to be approximately 0.31 times the potency of PTU in causing enlargement of thyroid gland, 0.06 times in effect on depression in plasma thyroid hormone, and 0.08 times in inhibitory effects on biosynthesis of thyroid hormone in the gland. It might be concluded that thyroid hormone synthesis is not so much suppressed to the degree expected from the enlargement of thyroid gland when goitrin is administered orally to the chick.
Akiba Y et al; Poult Sci 55(2): 716-719 (1976)
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ Effects of dietary R-goitrin (200 ppm) ... on GST activity, binding of aflatoxin B1 (AFB1) to DNA, in vivo, and biliary excretion of thiol conjugates of AFB1 in rats were studied. Increases of GST activities (1.9-fold) were accompanied by reductions in AFB1-DNA binding (43%) and increases (1.7-fold) in biliary excretion of AFB1-thiol conjugates in R-goitrin ...groups... . Microsomal aflatoxin 8,9-epoxidase activities were not increased in either treatment group.
Chang Y et al; Carcinogenesis 8(4): 585-590 (1987)
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ In male and female rats, R-goitrin treatment increased the relative liver weights; in some of the enlarged livers a high incidence of mitotic figures was observed. R-goitrin treatment increased the relative thyroid weight, more in male rats than in females. The thyroids of R-goitrin treated rats were either hyperplastic or had most follicles filled with pale-staining colloid and rarely follicles with normal, well-stained colloid. At certain doses, R-goitrin increased serum triglycerides, cholesterol, total protein, albumin and calcium, but it decreased serum thyroxine and urea. However, most of these changes in serum chemistry were small. R-goitrin caused a temporary increase in urinary ascorbic acid output in both sexes, but the liver ascorbic acid level was increased only in female rats. The duration of pentobarbital-induced sleep was significantly prolonged by R-goitrin pretreatment only in male rats.
Nishie K et al; Food and Chem Toxicol 20 (3): 279-287 (1982)
/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ Diets containing 500 g high-glucosinolate rapeseed meal/kg or an equivalent amount of soybean meal as the only protein supplement were fed to layer-type chickens and two broiler strains from 1 to 56 days of age. Additional groups of the former were maintained on the diets until they were 16 and 28 days old. The rapeseed meal produced thyroid hypertrophy in all strains but reduced the growth rate of only one of the broiler strains. The livers of chickens fed on rapeseed meal were enlarged and DNA analysis indicated hyperplasia, but no macroscopic lesions were found. The activities of aspartate transaminase, lactate dehydrogenase and alkaline phosphatase in the plasma were increased by rapeseed meal, suggesting liver damage. In all strains, feeding rapeseed meal increased plasma total protein, albumin and cholesterol and decreased urate. Hyperglycemia accompanied by a decrease in plasma triglycerides occurred in the layer strain. Through its extra-thyroidal toxicity (-)5-vinyl-oxazolidine-2-thione (goitrin) was probably responsible for most of these changes./rapeseed/
Pearson AW et al; Br Poult Sci 24(3): 417-427 (1983)
For more Non-Human Toxicity Excerpts (Complete) data for GOITRIN (10 total), please visit the HSDB record page.

9.2 Ecological Information

9.2.1 Natural Pollution Sources

Goitrin comes from rape/seed/.
Schmid A et al; Tierarztl Prax 20(3): 321-325 (1992)

9.2.2 Milk Concentrations

When rape cake was fed /to cows/ at 0.39, 1.9 and 3.9% resp. of the total feed this resulted in medium goitrin values of 37, 163 and 707 micrograms/l milk. These values correspond to a transfer of about 0.1% of the original progoitrin content in the feed. 12 h after the last rape feeding the amount of goitrin in the milk was below the detection limit of 7 ppb.
Bachmann M et al; Z Lebensm Unters Forsch 181 (5): 375-8 (1985)

10 Literature

10.1 Consolidated References

10.2 NLM Curated PubMed Citations

10.3 Springer Nature References

10.4 Wiley References

10.5 Chemical Co-Occurrences in Literature

10.6 Chemical-Gene Co-Occurrences in Literature

10.7 Chemical-Disease Co-Occurrences in Literature

11 Patents

11.1 Depositor-Supplied Patent Identifiers

11.2 WIPO PATENTSCOPE

11.3 Chemical Co-Occurrences in Patents

11.4 Chemical-Disease Co-Occurrences in Patents

11.5 Chemical-Gene Co-Occurrences in Patents

12 Interactions and Pathways

12.1 Chemical-Target Interactions

13 Biological Test Results

13.1 BioAssay Results

14 Taxonomy

The LOTUS Initiative for Open Natural Products Research: frozen dataset union wikidata (with metadata) | DOI:10.5281/zenodo.5794106

15 Classification

15.1 MeSH Tree

15.2 ChEBI Ontology

15.3 ChemIDplus

15.4 IUPHAR / BPS Guide to PHARMACOLOGY Target Classification

15.5 ChEMBL Target Tree

15.6 NORMAN Suspect List Exchange Classification

15.7 EPA DSSTox Classification

15.8 LOTUS Tree

15.9 MolGenie Organic Chemistry Ontology

16 Information Sources

  1. CAS Common Chemistry
    LICENSE
    The data from CAS Common Chemistry is provided under a CC-BY-NC 4.0 license, unless otherwise stated.
    https://creativecommons.org/licenses/by-nc/4.0/
  2. ChemIDplus
    ChemIDplus Chemical Information Classification
    https://pubchem.ncbi.nlm.nih.gov/source/ChemIDplus
  3. EPA DSSTox
    CompTox Chemicals Dashboard Chemical Lists
    https://comptox.epa.gov/dashboard/chemical-lists/
  4. 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
  5. FDA Global Substance Registration System (GSRS)
    LICENSE
    Unless otherwise noted, the contents of the FDA website (www.fda.gov), both text and graphics, are not copyrighted. They are in the public domain and may be republished, reprinted and otherwise used freely by anyone without the need to obtain permission from FDA. Credit to the U.S. Food and Drug Administration as the source is appreciated but not required.
    https://www.fda.gov/about-fda/about-website/website-policies#linking
  6. Hazardous Substances Data Bank (HSDB)
  7. ChEBI
  8. LOTUS - the natural products occurrence database
    LICENSE
    The code for LOTUS is released under the GNU General Public License v3.0.
    https://lotus.nprod.net/
  9. ChEMBL
    LICENSE
    Access to the web interface of ChEMBL is made under the EBI's Terms of Use (http://www.ebi.ac.uk/Information/termsofuse.html). The ChEMBL data is made available on a Creative Commons Attribution-Share Alike 3.0 Unported License (http://creativecommons.org/licenses/by-sa/3.0/).
    http://www.ebi.ac.uk/Information/termsofuse.html
  10. 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
  11. IUPHAR/BPS Guide to PHARMACOLOGY
    LICENSE
    The Guide to PHARMACOLOGY database is licensed under the Open Data Commons Open Database License (ODbL) https://opendatacommons.org/licenses/odbl/. Its contents are licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (http://creativecommons.org/licenses/by-sa/4.0/)
    https://www.guidetopharmacology.org/about.jsp#license
    Guide to Pharmacology Target Classification
    https://www.guidetopharmacology.org/targets.jsp
  12. Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
    LICENSE
    Copyright (c) 2022 Haz-Map(R). All rights reserved. Unless otherwise indicated, all materials from Haz-Map are copyrighted by Haz-Map(R). No part of these materials, either text or image may be used for any purpose other than for personal use. Therefore, reproduction, modification, storage in a retrieval system or retransmission, in any form or by any means, electronic, mechanical or otherwise, for reasons other than personal use, is strictly prohibited without prior written permission.
    https://haz-map.com/About
  13. Human Metabolome Database (HMDB)
    LICENSE
    HMDB is offered to the public as a freely available resource. Use and re-distribution of the data, in whole or in part, for commercial purposes requires explicit permission of the authors and explicit acknowledgment of the source material (HMDB) and the original publication (see the HMDB citing page). We ask that users who download significant portions of the database cite the HMDB paper in any resulting publications.
    http://www.hmdb.ca/citing
  14. Japan Chemical Substance Dictionary (Nikkaji)
  15. Natural Product Activity and Species Source (NPASS)
  16. MassBank Europe
  17. 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
  18. 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
    2-Oxazolidinethione, 5-ethenyl-
    http://www.nist.gov/srd/nist1a.cfm
  19. SpectraBase
  20. Springer Nature
  21. Wikidata
  22. Wikipedia
  23. Wiley
  24. PubChem
  25. Medical Subject Headings (MeSH)
    LICENSE
    Works produced by the U.S. government are not subject to copyright protection in the United States. Any such works found on National Library of Medicine (NLM) Web sites may be freely used or reproduced without permission in the U.S.
    https://www.nlm.nih.gov/copyright.html
  26. 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/
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  27. MolGenie
    MolGenie Organic Chemistry Ontology
    https://github.com/MolGenie/ontology/
  28. PATENTSCOPE (WIPO)
CONTENTS