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. The API supports compound searching by name, SMILES, InChI, InChIKey, molecular formula, mass, and elemental composition. Authenticated users can retrieve compound records with detailed properties, fetch external references, images, and MOL files, and perform batch operations. A tools endpoint supports chemical format conversions and InChIKey validation. All requests require an API key obtained from the RSC Developer Portal.
  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
    QueryResponse:
      type: object
      description: Response from a filter query submission
      properties:
        queryId:
          type: string
          description: Unique identifier for the submitted 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
  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.