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PubChem

PubChem Structure Search API

Chemical structure search operations

Documentation Provider Profile APIs.io OpenAPI GitHub

PubChem Structure Search API is one of 7 APIs that PubChem publishes on the APIs.io network, described by a machine-readable OpenAPI specification.

Tagged areas include Structure Search. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

This API exposes 5 operations across 5 paths, and defines 2 schemas. It is described by OpenAPI 3.2.0, at version 1.0.0.

Requests are made against a single base URL, https://pubchem.ncbi.nlm.nih.gov/rest/pug.

5 operations 5 paths 2 schemas 5 GET

Metadata

The identity and technical contract details declared by the specification.

Specification
OpenAPI 3.2.0
API Version
1.0.0
Base URL
https://pubchem.ncbi.nlm.nih.gov/rest/pug
Contact
pubchem-help@ncbi.nlm.nih.gov
License
Public Domain
Resource Areas
1

Paths & Operations 5

Across 5 paths, the API surfaces 5 operations — 5 GET. Each is listed below with its method, path, parameters, and response codes.

Structure Search 5

Chemical structure search operations

GET
/compound/fastsubstructure/smiles/{smiles}/cids/{format}
Substructure search by SMILES
13 params → 200400404503504
GET
/compound/fastsuperstructure/cid/{cid}/cids/{format}
Superstructure search by CID
7 params → 200400404503504
GET
/compound/fastsimilarity_2d/cid/{cid}/cids/{format}
2D similarity search by CID
7 params → 200400404503504
GET
/compound/fastidentity/smiles/{smiles}/cids/{format}
Identity search by SMILES
7 params → 200400404503504
GET
/compound/fastformula/{formula}/cids/{format}
Molecular formula search
7 params → 200400404503504

Schemas 2

The contract defines 2 schemas that model the data the API accepts and returns. The most detailed are Fault (1 property), IdentifierList (1 property). Each schema is shown below with its type and property counts.

IdentifierList
object
List of identifiers
1 property
Fault
object
Error response
1 property

Specification

The full machine-readable OpenAPI contract behind this narrative.

Source

pubchem-structure-search-api-openapi.yml Raw ↑

Other APIs PubChem publishes across the network.

PubChem PUG View API
AE Profile APIs.io
PubChem PUG SOAP API
AE Profile APIs.io
PubChem Structure Image Service
AE Profile APIs.io
PubChem Identifier Exchange Service
AE Profile APIs.io
PubChem Compounds API
AE Profile APIs.io
PubChem Utilities API
AE Profile APIs.io
#Structure Search
← Back to P APIs
API Details
ID
pubchem:pubchem-structure-search-api
Base URL
https://pubchem.ncbi.nlm.nih.gov/rest/pug
Docs
https://pubchem.ncbi.nlm.nih.gov/docs/pug-rest
Provider
PubChem
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