RSC

RSC Filter API

Search and filter chemical compounds by various properties.

GitHub OpenAPI

Operations 8

POST /filter/name Filter Compounds By Name #
POST /filter/smiles Filter Compounds By SMILES #
POST /filter/inchi Filter Compounds By InChI #
POST /filter/inchikey Filter Compounds By InChIKey #
POST /filter/formula Filter Compounds By Formula #
POST /filter/mass Filter Compounds By Mass #
GET /filter/{queryId}/status Get Filter Query Status #
GET /filter/{queryId}/results Get Filter Query Results #

Documentation

📖
Documentation
https://developer.rsc.org/compounds-v1/apis

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/rsc/refs/heads/main/openapi/rsc-filter-api-openapi.yml

Other Resources

🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/rsc/refs/heads/main/apis.yml

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OpenAPI Specification

rsc-filter-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: RSC ChemSpider Compounds Filter API
  description: The RSC ChemSpider Compounds API provides programmatic access to the ChemSpider chemical database, which contains over 88 million unique chemical compounds.
  version: '1'
  contact:
    name: RSC Developer Support
    url: https://developer.rsc.org/
  termsOfService: https://www.rsc.org/legal/
servers:
- url: https://api.rsc.org/compounds/v1
  description: ChemSpider Production API
tags:
- name: Filter
  description: Search and filter chemical compounds by various properties.
paths:
  /filter/name:
    post:
      operationId: filterByName
      summary: Filter Compounds By Name
      description: Submit a name query to search for chemical compounds matching the specified name. Returns a query ID that can be used to poll for results using the filter status and results endpoints.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - name
              properties:
                name:
                  type: string
                  description: The compound name to search for
                orderBy:
                  type: string
                  description: Sort field for results
                  enum:
                  - recordId
                  - massDefect
                  - molecularWeight
                  - referenceCount
                  - dataSourceCount
                  - pubmedCount
                  - rscCount
                orderDirection:
                  type: string
                  description: Sort direction
                  enum:
                  - ascending
                  - descending
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '400':
          description: Invalid request
        '401':
          description: Unauthorized - API key missing or invalid
      security:
      - apiKeyAuth: []
  /filter/smiles:
    post:
      operationId: filterBySmiles
      summary: Filter Compounds By SMILES
      description: Submit a SMILES string to find matching chemical compounds. Returns a query ID for polling results.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - smiles
              properties:
                smiles:
                  type: string
                  description: The SMILES string for the compound
                orderBy:
                  type: string
                  description: Sort field for results
                orderDirection:
                  type: string
                  description: Sort direction
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /filter/inchi:
    post:
      operationId: filterByInchi
      summary: Filter Compounds By InChI
      description: Submit an InChI string to find matching chemical compounds. Returns a query ID for polling results.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - inchi
              properties:
                inchi:
                  type: string
                  description: The InChI string for the compound
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /filter/inchikey:
    post:
      operationId: filterByInchikey
      summary: Filter Compounds By InChIKey
      description: Submit an InChIKey to find the matching chemical compound. Returns a query ID for polling results.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - inchikey
              properties:
                inchikey:
                  type: string
                  description: The InChIKey for the compound
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /filter/formula:
    post:
      operationId: filterByFormula
      summary: Filter Compounds By Formula
      description: Search for compounds matching a given molecular formula. Optionally restrict to specific data sources.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - formula
              properties:
                formula:
                  type: string
                  description: Molecular formula (e.g., C6H12O6)
                dataSources:
                  type: array
                  items:
                    type: string
                  description: List of data sources to restrict search
                orderBy:
                  type: string
                  description: Sort field
                orderDirection:
                  type: string
                  description: Sort direction
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /filter/mass:
    post:
      operationId: filterByMass
      summary: Filter Compounds By Mass
      description: Search for compounds within a mass range. The mass and mass_range parameters define the target mass and acceptable deviation.
      tags:
      - Filter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - mass
              - massRange
              properties:
                mass:
                  type: number
                  description: Target molecular mass
                massRange:
                  type: number
                  description: Acceptable mass deviation (+/-)
                dataSources:
                  type: array
                  items:
                    type: string
                  description: Data sources to restrict search
                orderBy:
                  type: string
                  description: Sort field
                orderDirection:
                  type: string
                  description: Sort direction
      responses:
        '200':
          description: Query accepted; returns query ID
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/QueryResponse'
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /filter/{queryId}/status:
    get:
      operationId: getFilterStatus
      summary: Get Filter Query Status
      description: Poll the status of a previously submitted filter query using its query ID. Returns the current status, result count, and any message.
      tags:
      - Filter
      parameters:
      - name: queryId
        in: path
        required: true
        schema:
          type: string
        description: The query ID returned by a filter endpoint
      responses:
        '200':
          description: Query status
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/FilterStatus'
        '401':
          description: Unauthorized
        '404':
          description: Query not found
      security:
      - apiKeyAuth: []
  /filter/{queryId}/results:
    get:
      operationId: getFilterResults
      summary: Get Filter Query Results
      description: Retrieve the record IDs for a completed filter query. Supports pagination via start and count parameters.
      tags:
      - Filter
      parameters:
      - name: queryId
        in: path
        required: true
        schema:
          type: string
        description: The query ID returned by a filter endpoint
      - name: start
        in: query
        required: false
        schema:
          type: integer
          minimum: 0
        description: Zero-based index of first result to return
      - name: count
        in: query
        required: false
        schema:
          type: integer
          minimum: 1
        description: Number of results to return
      responses:
        '200':
          description: Array of record IDs
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/FilterResults'
        '401':
          description: Unauthorized
        '404':
          description: Query not found
      security:
      - apiKeyAuth: []
components:
  schemas:
    FilterResults:
      type: object
      description: Results from a completed filter query
      properties:
        queryId:
          type: string
          description: The query ID
        results:
          type: array
          items:
            type: integer
          description: Array of ChemSpider record IDs matching the query
    FilterStatus:
      type: object
      description: Status of a filter query
      properties:
        status:
          type: string
          description: Current query status (Processing, Complete, Failed)
          enum:
          - Processing
          - Complete
          - Failed
        count:
          type: integer
          description: Number of results found so far
        message:
          type: string
          description: Status message or error description
    QueryResponse:
      type: object
      description: Response from a filter query submission
      properties:
        queryId:
          type: string
          description: Unique identifier for the submitted query
  securitySchemes:
    apiKeyAuth:
      type: apiKey
      in: header
      name: apikey
      description: API key obtained from the RSC Developer Portal at developer.rsc.org. Register and create an application to receive an API key.