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OpenAPI Specification
openapi: 3.2.0
info:
title: PubChem PUG REST Compounds API
description: 'PUG REST is a REST-style version of PUG (Power User Gateway), a web interface for accessing PubChem data and services. PUG REST provides access to the data in PubChem Compounds as well as specialized chemical structure search services.
The service supports various input formats including chemical names, SMILES strings, InChI identifiers, and direct database identifiers. It can return data in multiple formats including JSON, XML, CSV, SDF, and PNG images.
'
version: 1.0.0
contact:
email: pubchem-help@ncbi.nlm.nih.gov
license:
name: Public Domain
url: https://www.ncbi.nlm.nih.gov/home/about/policies/
servers:
- url: https://pubchem.ncbi.nlm.nih.gov/rest/pug
description: PubChem PUG REST API
tags:
- name: Compounds
description: Operations on compound records
paths:
/compound/cid/{cids}/{format}:
get:
tags:
- Compounds
summary: Get compound records by CID
description: Retrieve full compound records for the specified CIDs
parameters:
- name: cids
in: path
required: true
schema:
type: string
description: Comma-separated list of Compound IDs (CIDs)
example: 2244,5793
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- SDF
- PNG
- TXT
default: JSON
description: Output format
- name: record_type
in: query
schema:
type: string
enum:
- 2d
- 3d
default: 2d
description: Type of conformer for compounds
- name: image_size
in: query
schema:
type: string
default: large
description: Image size - large (300x300), small (100x100), or custom (e.g. 320x240)
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/CompoundRecords'
application/xml:
schema:
$ref: '#/components/schemas/CompoundRecords'
chemical/x-mdl-sdfile:
schema:
type: string
image/png:
schema:
type: string
format: binary
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
/compound/name/{name}/{format}:
get:
tags:
- Compounds
summary: Get compound records by name
description: Retrieve compound records for the specified chemical name
parameters:
- name: name
in: path
required: true
schema:
type: string
description: Chemical name
example: aspirin
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- SDF
- PNG
- TXT
default: JSON
description: Output format
- name: name_type
in: query
schema:
type: string
enum:
- word
- complete
description: Name matching type
- name: record_type
in: query
schema:
type: string
enum:
- 2d
- 3d
default: 2d
description: Type of conformer for compounds
- name: image_size
in: query
schema:
type: string
default: large
description: Image size for PNG format
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/CompoundRecords'
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
/compound/smiles/{smiles}/{format}:
get:
tags:
- Compounds
summary: Get compound records by SMILES
description: Retrieve compound records for the specified SMILES string
parameters:
- name: smiles
in: path
required: true
schema:
type: string
description: SMILES string (URL-encoded)
example: CCCC
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- SDF
- PNG
- TXT
default: JSON
description: Output format
- name: record_type
in: query
schema:
type: string
enum:
- 2d
- 3d
default: 2d
description: Type of conformer for compounds
- name: image_size
in: query
schema:
type: string
default: large
description: Image size for PNG format
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/CompoundRecords'
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
/compound/inchikey/{inchikey}/{format}:
get:
tags:
- Compounds
summary: Get compound records by InChI Key
description: Retrieve compound records for the specified InChI Key
parameters:
- name: inchikey
in: path
required: true
schema:
type: string
description: InChI Key
example: BPGDAMSIGCZZLK-UHFFFAOYSA-N
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- SDF
- PNG
- TXT
default: JSON
description: Output format
- name: record_type
in: query
schema:
type: string
enum:
- 2d
- 3d
default: 2d
description: Type of conformer for compounds
- name: image_size
in: query
schema:
type: string
default: large
description: Image size for PNG format
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/CompoundRecords'
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
/compound/cid/{cids}/property/{properties}/{format}:
get:
tags:
- Compounds
summary: Get compound properties
description: Retrieve specific properties for the specified compounds
parameters:
- name: cids
in: path
required: true
schema:
type: string
description: Comma-separated list of Compound IDs (CIDs)
example: 1,2,3,4,5
- name: properties
in: path
required: true
schema:
type: string
description: Comma-separated list of property names
example: MolecularFormula,MolecularWeight,InChIKey
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- CSV
- TXT
default: JSON
description: Output format
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/PropertyTable'
text/csv:
schema:
type: string
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
/compound/cid/{cids}/synonyms/{format}:
get:
tags:
- Compounds
summary: Get compound synonyms
description: Retrieve synonyms for the specified compounds
parameters:
- name: cids
in: path
required: true
schema:
type: string
description: Comma-separated list of Compound IDs (CIDs)
example: '2244'
- name: format
in: path
required: true
schema:
type: string
enum:
- XML
- JSON
- JSONP
- ASNT
- ASNB
- TXT
default: JSON
description: Output format
- name: callback
in: query
schema:
type: string
description: Callback function name for JSONP format
responses:
'200':
description: Successful response
content:
application/json:
schema:
$ref: '#/components/schemas/InformationList'
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'503':
$ref: '#/components/responses/ServiceUnavailable'
components:
schemas:
PropertyTable:
type: object
description: Table of compound properties
properties:
PropertyTable:
type: object
properties:
Properties:
type: array
items:
type: object
properties:
CID:
type: integer
MolecularFormula:
type: string
MolecularWeight:
type: string
SMILES:
type: string
InChI:
type: string
InChIKey:
type: string
IUPACName:
type: string
XLogP:
type: number
ExactMass:
type: string
MonoisotopicMass:
type: string
TPSA:
type: number
Complexity:
type: integer
Charge:
type: integer
HBondDonorCount:
type: integer
HBondAcceptorCount:
type: integer
RotatableBondCount:
type: integer
HeavyAtomCount:
type: integer
CompoundRecord:
type: object
description: A single compound record
properties:
id:
type: object
properties:
id:
type: object
properties:
cid:
type: integer
atoms:
type: object
bonds:
type: object
stereo:
type: array
items:
type: object
props:
type: array
items:
type: object
InformationList:
type: object
description: List of information records
properties:
InformationList:
type: object
properties:
Information:
type: array
items:
type: object
properties:
CID:
type: integer
SID:
type: integer
AID:
type: integer
Synonym:
type: array
items:
type: string
Title:
type: string
Description:
type: string
CompoundRecords:
type: object
description: Collection of compound records
properties:
PC_Compounds:
type: array
items:
$ref: '#/components/schemas/CompoundRecord'
Fault:
type: object
description: Error response
properties:
Fault:
type: object
properties:
Code:
type: string
Message:
type: string
Details:
type: array
items:
type: string
responses:
ServiceUnavailable:
description: Too many requests or server is busy, retry later
content:
application/json:
schema:
$ref: '#/components/schemas/Fault'
application/xml:
schema:
$ref: '#/components/schemas/Fault'
text/html:
schema:
type: string
NotFound:
description: The input record was not found (e.g. invalid CID)
content:
application/json:
schema:
$ref: '#/components/schemas/Fault'
application/xml:
schema:
$ref: '#/components/schemas/Fault'
BadRequest:
description: Request is improperly formed (syntax error in the URL, POST body, etc.)
content:
application/json:
schema:
$ref: '#/components/schemas/Fault'
application/xml:
schema:
$ref: '#/components/schemas/Fault'