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PUG REST

This document describes the REST-style version of PUG (Power User Gateway), a web interface for accessing PubChem data and services. It details both the syntax of the HTTP requests, and the available functions. This is more of a specification document; a less formal, tutorial-style PUG REST document is now available. For comments, help, or to suggest new functionality, please contact pubchem-help@ncbi.nlm.nih.gov.

Additional information of PUG REST can also be found in the following papers:

Kim S, Thiessen PA, Cheng T, Yu B, Bolton EE. An update on PUG-REST: RESTful interface for programmatic access to PubChem. Nucleic Acids Res. 2018 July 2; 46(W1):W563-570. doi:10.1093/nar/gky294.
[PubMed PMID: 29718389] [PubMed Central ID: PMC6030920] [Free Full Text]
Kim S, Thiessen PA, Bolton EE, Bryant SH. PUG-SOAP and PUG-REST: web services for programmatic access to chemical information in PubChem. Nucleic Acids Res. 2015 Jul 1; 43(W1):W605-W611. doi: 10.1093/nar/gkv396.
[PubMed PMID: 25934803] [PubMed Central PMCID: PMC4489244] [Free Full Text]
Kim S, Thiessen PA, Bolton EE. Programmatic Retrieval of Small Molecule Information from PubChem Using PUG-REST. In Kutchukian PS, ed. Chemical Biology Informatics and Modeling. Methods in Pharmacology and Toxicology. New York, NY: Humana Press, 2018, pp. 1-24. doi:10.1007/7653_2018_30.
[Full Text]

USAGE POLICY: Please note that PUG REST is not designed for very large volumes (millions) of requests. We ask that any script or application not make more than 5 requests per second, in order to avoid overloading the PubChem servers. To check additional request volume limitations, please read this document. If you have a large data set that you need to compute with, please contact us for help on optimizing your task, as there are likely more efficient ways to approach such bulk queries.

Example Perl scripts demonstrating how to access PubChem data through PUG-REST are available here.

HTTP Interface Details

Full-record Retrieval

Compound Property Tables

Asynchronous Operations

Substructure / Superstructure

Similarity

Identity

Molecular Formula

Synchronous (“Fast”) Inputs

Search Within a Search

URL-based API

The URL Path

Most – if not all – of the information the service needs to produce its results is encoded into the URL. The general form of the URL has three parts – input, operation, and output – after the common prefix, followed by operation options as URL arguments (after the ‘?’):

https://pubchem.ncbi.nlm.nih.gov/rest/pug/<input specification>/<operation specification>/[<output specification>][?<operation_options>]

Input

The input portion of the URL tells the service which records to use as the subject of the query. This is further subdivided into two or more locations in the URL “path” as follows:

<input specification> = <domain>/<namespace>/<identifiers>

<structure search> = {substructure | superstructure | similarity | identity}/{smiles | inchi | sdf | cid}

<fast search> = {fastidentity | fastsimilarity_2d | fastsimilarity_3d | fastsubstructure | fastsuperstructure}/{smiles | smarts | inchi | sdf | cid} | fastformula

<xref> = xref / {RegistryID | RN | PubMedID | MMDBID | ProteinGI | NucleotideGI | TaxonomyID | MIMID | GeneID | ProbeID | PatentID}

<source name> = any valid PubChem depositor name

<assay target> = gi | proteinname | geneid | genesymbol | accession

<other inputs> = sources / [substance, assay] | sourcetable | conformers | annotations/[sourcename/<source name> | heading/<heading>] | classification

<identifiers> = comma-separated list of positive integers (e.g. cid, sid, aid) or identifier strings (source, inchikey, formula); in some cases only a single identifier string (name, smiles, xref; inchi, sdf by POST only)

For example, to access CID 2244 (aspirin), one would construct the first part of the URL this way:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/<operation specification>/[<output specification>]

Some source names contain the ‘/’ (forward slash) character, which is incompatible with the URL syntax; for these, replace the ‘/’ with a ‘.’ (period) in the URL. Other special characters may need to be escaped, such as ‘&’ should be replaced by ‘%26’. For example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceid/DTP.NCI/<operation specification>/[<output specification>]

Operation

The operation part of the URL tells the service what to do with the input records – such as to retrieve whole record data blobs or specific properties of a compound, etc. The construction of this part of the “path” will depend on what the operation is. Currently, if no operation is specified at all, the default is to retrieve the entire record. What operations are available are, of course, dependent on the input domain – that is, certain operations are applicable only to compounds and not assays, for example.

<compound property> = property / [comma-separated list of property tags]

<xrefs> = xrefs / [comma-separated list of xrefs tags]

<target_type> = {ProteinGI, ProteinName, GeneID, GeneSymbol}

<doseresponse> = doseresponse/sid

gene domain <operation specification> = summary | aids | concise | pwaccs

protein domain <operation specification> = summary | aids | concise | pwaccs

pathway domain <operation specification> = summary | cids | geneids | accessions

taxonomy domain <operation specification> = summary | aids

cell domain <operation specification> = summary | aids

For example, to access the molecular formula and InChI key for CID 2244, one would use a URL like:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/property/MolecularFormula,InChIKey/[<output specification>]

Output

The final portion of the URL tells the service what output format is desired. Note that this is formally optional, as output format can also be specified in the HTTP Accept field of the request header – see below for more detail.

<output specification> = XML | ASNT | ASNB | JSON | JSONP [ ?callback=<callback name> ] | SDF | CSV | PNG | TXT

ASNT is NCBI’s text (human-readable) variant of ASN.1; ASNB is standard binary ASN.1 and is currently returned as Base64-encoded ascii text. Note that not all formats are applicable to the results of all operations; one cannot, for example, retrieve a whole compound record as CSV or a property table as SDF. TXT output is only available in a restricted set of cases where all the information is the same – for example, synonyms for a single CID where there is one synonym per line.

For example, to access the molecular formula for CID 2244 in JSON format, one would use the (now complete) URL:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/property/MolecularFormula/JSON

JSONP takes an optional callback function name (which defaults to “callback” if not specified). For example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/property/MolecularFormula/JSONP?callback=my_callback

HTTP Interface Details

Request Header

The HTTP request header may be used to supply some types of information to this service.

The value of “Accept” may be a MIME type that will tell the service what output format is accepted by the client, and hence what format is returned by the server. The allowed values are:

Accept value	Output Format
application/xml	XML
application/json	JSON
application/javascript	JSONP
application/ber-encoded	ASNB
chemical/x-mdl-sdfile	SDF
text/csv	CSV
image/png	PNG
text/plain	TXT

The Content-Type in the HTTP response header will also be set by the reverse of the above table, e.g. XML data will have “Content-Type: application/xml”.

For example, the URL:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244

with “Accept: chemical/x-mdl-sdfile” in the request header will return CID 2244 in SDF format.

For proper transmission of certain special characters, strings passed e.g. for SMILES input may need to be URL encoded; for example, “smiles=C1C[CH+]1” should be encoded as “smiles=C1C%5BCH%2B%5D1”. For correct parsing of any POST body, the proper content type header must be included in the request header (see below).

Request (POST) Body

Some parts of the URL may be moved to the body of a POST request, rather than being part of the URL path. For example, a list of CID integers – which may be too long to fit within the size limitations of a GET request URL – may be moved to the POST body:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/property/MolecularFormula,MolecularWeight/CSV

with “cid=1,2,3,4,5” in the POST body, would retrieve a CSV-formatted table of results for these CIDs. Note that for the service to parse such POST information correctly, the “Content-Type: application/x-www-form-urlencoded” value must be included in the request header. One may also use “Content-Type: multipart/form-data” with the POST body formatted accordingly. See here for more information on content type encoding.

Status Codes

If the operation was successful, the HTTP status code will be 200 (OK). If the server encounters an error, it will return an HTTP status code that gives some indication of what went wrong; possibly along with, depending on the output format (such as in a <Fault> tag in XML), some additional more human-readable detail message(s). The codes in the 400-range are errors on the client side, and those in the 500 range indicate a problem on the server side; the codes currently in use are:

HTTP Status	Error Code	General Error Category
200	(none)	Success
202	(none)	Accepted (asynchronous operation pending)
400	PUGREST.BadRequest	Request is improperly formed (syntax error in the URL, POST body, etc.)
404	PUGREST.NotFound	The input record was not found (e.g. invalid CID)
405	PUGREST.NotAllowed	Request not allowed (such as invalid MIME type in the HTTP Accept header)
504	PUGREST.Timeout	The request timed out, from server overload or too broad a request
503	PUGREST.ServerBusy	Too many requests or server is busy, retry later
501	PUGREST.Unimplemented	The requested operation has not (yet) been implemented by the server
500	PUGREST.ServerError	Some problem on the server side (such as a database server down, etc.)
500	PUGREST.Unknown	An unknown error occurred

HTTPS

NCBI now requires HTTPS (URLs beginning with https://) for web service access.

Schemas

A schema for the XML data returned by PUG REST may be found at:

https://pubchem.ncbi.nlm.nih.gov/pug_rest/pug_rest.xsd

Some operations (such as full record retrieval) may use the standard PubChem schema at:

https://ftp.ncbi.nlm.nih.gov/pubchem/specifications/pubchem.xsd

Classification data is returned with this schema:

https://pubchem.ncbi.nlm.nih.gov/pug_rest/hierarchy_data.xsd

Operations

Full-record Retrieval

Returns full records for PubChem substances, compounds, and assays.

Valid output formats for substances and compounds are XML, JSON(P), ASNT/B, SDF, and PNG. A compound record may optionally be either 2D or 3D; substances are always given with coordinates as deposited. For PNG output, only the first SID or CID is used if the input is a list.

Option	Allowed Values (default in bold)	Meaning
record_type	2d, 3d	Type of conformer for compounds
image_size	large, small, <width>x<height>	Image size: large (300x300), small (100x100), or arbitrary (e.g. 320x240)

Valid output formats for assays are XML, JSON(P), ASNT/B, and CSV. Assay record retrieval is limited to a single AID with 10000 SIDs at a time; a subset of the SIDs of an assay may be specified as options:

Option	Allowed Values	Meaning
sid	listkey, or comma-separated integers	SID rows to retrieve for an assay
listkey	valid SID listkey	listkey containing SIDs, if using sid=listkey

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceid/IBM/5F1CA2B314D35F28C7F94168627B29E3/ASNT

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceid/DTP.NCI/747285/SDF

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceid/DTP.NCI/747285/PNG

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/SDF

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/PNG

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/SDF?record_type=3d

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/PNG?record_type=3d&image_size=small

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/name/aspirin/SDF

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/inchikey/BPGDAMSIGCZZLK-UHFFFAOYSA-N/SDF

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/ASNT?version=1.1 (for old-version)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/CSV?sid=26736081,26736082,26736083

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/concise/CSV

Compound Property Tables

Returns a table of compound properties. More than one property may be requested, in a comma-separated list of property tags in the request URL. Valid output formats for the property table are: XML, ASNT/B, JSON(P), CSV, and TXT (limited to a single property). Available properties are:

Property	Notes
MolecularFormula	Molecular formula.
MolecularWeight	The molecular weight is the sum of all atomic weights of the constituent atoms in a compound, measured in g/mol. In the absence of explicit isotope labelling, averaged natural abundance is assumed. If an atom bears an explicit isotope label, 100% isotopic purity is assumed at this location.
CanonicalSMILES	Canonical SMILES (Simplified Molecular Input Line Entry System) string. It is a unique SMILES string of a compound, generated by a “canonicalization” algorithm.
IsomericSMILES	Isomeric SMILES string. It is a SMILES string with stereochemical and isotopic specifications.
InChI	Standard IUPAC International Chemical Identifier (InChI). It does not allow for user selectable options in dealing with the stereochemistry and tautomer layers of the InChI string.
InChIKey	Hashed version of the full standard InChI, consisting of 27 characters.
IUPACName	Chemical name systematically determined according to the IUPAC nomenclatures.
Title	The title used for the compound summary page.
XLogP	Computationally generated octanol-water partition coefficient or distribution coefficient. XLogP is used as a measure of hydrophilicity or hydrophobicity of a molecule.
ExactMass	The mass of the most likely isotopic composition for a single molecule, corresponding to the most intense ion/molecule peak in a mass spectrum.
MonoisotopicMass	The mass of a molecule, calculated using the mass of the most abundant isotope of each element.
TPSA	Topological polar surface area, computed by the algorithm described in the paper by Ertl et al.
Complexity	The molecular complexity rating of a compound, computed using the Bertz/Hendrickson/Ihlenfeldt formula.
Charge	The total (or net) charge of a molecule.
HBondDonorCount	Number of hydrogen-bond donors in the structure.
HBondAcceptorCount	Number of hydrogen-bond acceptors in the structure.
RotatableBondCount	Number of rotatable bonds.
HeavyAtomCount	Number of non-hydrogen atoms.
IsotopeAtomCount	Number of atoms with enriched isotope(s)
AtomStereoCount	Total number of atoms with tetrahedral (sp3) stereo [e.g., (R)- or (S)-configuration]
DefinedAtomStereoCount	Number of atoms with defined tetrahedral (sp3) stereo.
UndefinedAtomStereoCount	Number of atoms with undefined tetrahedral (sp3) stereo.
BondStereoCount	Total number of bonds with planar (sp2) stereo [e.g., (E)- or (Z)-configuration].
DefinedBondStereoCount	Number of atoms with defined planar (sp2) stereo.
UndefinedBondStereoCount	Number of atoms with undefined planar (sp2) stereo.
CovalentUnitCount	Number of covalently bound units.
Volume3D	Analytic volume of the first diverse conformer (default conformer) for a compound.
XStericQuadrupole3D	The x component of the quadrupole moment (Qx) of the first diverse conformer (default conformer) for a compound.
YStericQuadrupole3D	The y component of the quadrupole moment (Qy) of the first diverse conformer (default conformer) for a compound.
ZStericQuadrupole3D	The z component of the quadrupole moment (Qz) of the first diverse conformer (default conformer) for a compound.
FeatureCount3D	Total number of 3D features (the sum of FeatureAcceptorCount3D, FeatureDonorCount3D, FeatureAnionCount3D, FeatureCationCount3D, FeatureRingCount3D and FeatureHydrophobeCount3D)
FeatureAcceptorCount3D	Number of hydrogen-bond acceptors of a conformer.
FeatureDonorCount3D	Number of hydrogen-bond donors of a conformer.
FeatureAnionCount3D	Number of anionic centers (at pH 7) of a conformer.
FeatureCationCount3D	Number of cationic centers (at pH 7) of a conformer.
FeatureRingCount3D	Number of rings of a conformer.
FeatureHydrophobeCount3D	Number of hydrophobes of a conformer.
ConformerModelRMSD3D	Conformer sampling RMSD in Å.
EffectiveRotorCount3D	Total number of 3D features (the sum of FeatureAcceptorCount3D, FeatureDonorCount3D, FeatureAnionCount3D, FeatureCationCount3D, FeatureRingCount3D and FeatureHydrophobeCount3D)
ConformerCount3D	The number of conformers in the conformer model for a compound.
Fingerprint2D	Base64-encoded PubChem Substructure Fingerprint of a molecule.

Example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/1,2,3,4,5/property/MolecularFormula,MolecularWeight,InChIKey/CSV

Synonyms

Returns a list of substance or compound synonyms. Valid output formats for synonyms are XML, JSON(P) , ASNT/B, and TXT (limited).

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/name/aspirin/synonyms/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/smiles/CCCC/synonyms/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sid/53789435/synonyms/TXT

Description

Returns the title and description for an S/CID, the same as used in the web summary pages for these records. Valid output formats are XML, JSON(P) , and ASNT/B.

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/1983/description/XML

SIDS / CIDS / AIDS

Returns a list of SIDs, CIDs, or AIDs. Possibly interconverts record identifiers, with options in the table below; these options, if present, must be specified as standard URL arguments (e.g. after the ‘?’). The list of identifiers may be grouped by input (e.g. when converting from one type to another); flattened to a unique target set (implied for TXT output); or stored on the server (which also implies flat), in which case a list key is returned. Valid output formats are XML, JSON(P), ASNT/B, and TXT.

Option	Allowed Values (default in bold)	Meaning
aids_type	all, active, inactive	Type of AIDs to return, given SIDs or CIDs
sids_type	all, active, inactive, doseresponse	Type of SIDs to return, given AIDs
sids_type	all, standardized, component	Type of SIDs to return, given CIDs
sids_type	original	Type of SIDs to return, given SIDs
cids_type	all, active, inactive	Type of CIDs to return, given AIDs
cids_type	all, standardized, component	Type of CIDs to return, given SIDs
cids_type	original, parent, component, preferred, similar_2d, similar_3d, same_stereo, same_isotopes, same_connectivity, same_tautomer, same_parent, same_parent_stereo, same_parent_isotopes, same_parent_connectivity, same_parent_tautomer	Type of CIDs to return, given CIDs
list_return	grouped, flat, listkey	Type of identifier list to return

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/name/glucose/sids/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/name/glucose/sids/XML?list_return=listkey

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/listkey/xxxxxx/sids/XML (where ‘xxxxxx’ is the listkey from the above URL)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/name/glucose/cids/XML?list_return=grouped

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/name/glucose/cids/XML?list_return=flat

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceall/MLSMR/sids/JSON?list_return=listkey

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sourceall/R%26D%20Chemicals/sids/XML?list_return=listkey

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sid/123061,123079/cids/XML?cids_type=all

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/sids/JSON

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/inchi/cids/JSON (where the POST body contains “inchi=InChI=1S/C3H8/c1-3-2/h3H2,1-2H3”)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/192180/cids/TXT?cids_type=component

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/aids/JSON?aids_type=active

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/sids/JSON?sids_type=component

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/2244/cids/TXT?cids_type=same_connectivity

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/21145249/cids/XML?cids_type=parent

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/sids/XML?sids_type=inactive

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/504526/sids/JSON?sids_type=doseresponse

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/type/doseresponse/aids/JSON

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/sourceall/DTP.NCI/aids/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/xref/PatentID/EP0711162A1/sids/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/name/aspirin/cids/XML?name_type=word

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/name/aspirin/cids/XML?name_type=complete

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/target/genesymbol/USP2/aids/TXT

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/target/gi/116516899/aids/JSON

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/activity/EC50/aids/TXT (where EC50 is case-sensitive)

Assay Description

Returns assay descriptions. Valid output formats are XML, JSON(P), and ASNT/B.

Example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/450/description/XML

Assay Targets

Return assay target information. Valid output formats are XML, JSON(P), ASNT/B, and TXT. Available target types are:

Target Type	Notes
ProteinGI	NCBI GI of a protein sequence
ProteinName	protein name
GeneID	NCBI Gene database identifier
GeneSymbol	gene symbol

Example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/490,1000/targets/ProteinGI,ProteinName,GeneID,GeneSymbol/XML

Assay Summary

Returns a summary of biological test results for the given SID(s) or CID(s), including assay experiment information, bioactivity, and target. Valid output formats are XML, JSON(P), ASNT/B, and CSV.

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/compound/cid/1000,1001/assaysummary/CSV

https://pubchem.ncbi.nlm.nih.gov/rest/pug/substance/sid/104234342/assaysummary/XML

There is also a per-AID assay summary available in a simplified format. Valid output formats are XML, JSON(P), and ASNT/B.

Example:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/1000/summary/XML

Assay Dose-Response

Returns assay dose-response data for a single AID with up to 1000 SID(s). Valid output formats are XML, JSON(P), ASNT/B, and CSV. A subset of the SIDs of an assay may be specified as options:

Option	Allowed Values	Meaning
sid	listkey, or comma-separated integers	SID rows to retrieve for an assay
listkey	valid SID listkey	listkey containing SIDs, if using sid=listkey

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/504526/doseresponse/XML

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/504526/doseresponse/CSV?sid=104169547,109967232

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/doseresponse/XML (with “aid=504526&sid=104169547,109967232” in the POST body)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/602332/sids/XML?sids_type=doseresponse&list_return=listkey

followed by

https://pubchem.ncbi.nlm.nih.gov/rest/pug/assay/aid/602332/doseresponse/CSV?sid=listkey&listkey=xxxxxx&listkey_count=100 (where ‘xxxxxx’ is the listkey returned by the previous URL)

Gene Summary

Returns a summary of gene: GeneID, Symbol, Name, TaxonomyID, Taxonomy, Description, and a list of Synonyms. Valid output formats are XML, JSON(P), and ASNT/B.

Examples:

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/geneid/1956,13649/summary/JSON (by GeneID)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/genesymbol/EGFR/summary/XML (by genesymbol, case insensitive and default to human)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/genesymbol/EGFR/10090/summary/JSON (mouse with NCBI TaxonomyID 9606)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/genesymbol/EGFR/Rattus%20norvegicus/summary/JSON (mouse with scientific taxonomy name)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/genesymbol/EGFR/Norway%20rat/summary/JSON (mouse with common taxonomy name)

https://pubchem.ncbi.nlm.nih.gov/rest/pug/gene/synonym/EGFR/summary/JSON (by synonym, note that one synonym may map to multiple GeneIDs)