openapi: 3.1.0 info: title: Sigma-Aldrich Product Search Pricing and Availability Structures API description: The Sigma-Aldrich Product Search API provides programmatic access to the Sigma-Aldrich product catalog — one of the largest collections of research chemicals, biochemicals, reagents, and laboratory supplies in the world. Researchers and LIMS systems can search products by catalog number, CAS number, product name, or chemical structure notation (SMILES/InChI) and retrieve detailed product information including specifications, safety data, pricing, and availability from global distribution centers. version: '1.0' contact: name: Sigma-Aldrich Customer Support url: https://www.sigmaaldrich.com/US/en/support/contact-us termsOfService: https://www.sigmaaldrich.com/US/en/terms-and-conditions license: name: Proprietary url: https://www.sigmaaldrich.com/US/en/terms-and-conditions servers: - url: https://api.sigmaaldrich.com/v1 description: Sigma-Aldrich Production API security: - ApiKeyAuth: [] tags: - name: Structures description: Chemical structure search using SMILES, InChI, or molecular formula notation for cheminformatics workflows. paths: /structures/search: post: operationId: searchByStructure summary: Search by Chemical Structure description: Search for products by chemical structure using SMILES or InChI notation. Supports exact match, substructure search, and similarity search modes. Returns products containing or matching the specified chemical structure. tags: - Structures requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/StructureSearchRequest' responses: '200': description: Structure search results returned successfully content: application/json: schema: $ref: '#/components/schemas/ProductSearchResults' '400': description: Invalid structure notation '401': description: Invalid or missing API key components: schemas: StructureSearchRequest: type: object required: - structure - searchType properties: structure: type: string description: Chemical structure in SMILES or InChI notation searchType: type: string enum: - exact - substructure - similarity description: Type of structure search to perform similarityThreshold: type: number minimum: 0 maximum: 1 default: 0.7 description: Minimum similarity score for similarity searches (0-1) notation: type: string enum: - smiles - inchi default: smiles description: Chemical structure notation format Product: type: object properties: catalogNumber: type: string description: Sigma-Aldrich catalog number name: type: string description: Product name description: type: string description: Product description brand: type: string description: Sigma-Aldrich brand (Sigma, Aldrich, Fluka, Supelco) casNumber: type: string description: CAS Registry Number formula: type: string description: Molecular formula (e.g., C2H6O for ethanol) molecularWeight: type: number description: Molecular weight in g/mol smiles: type: string description: SMILES notation for the chemical structure inchi: type: string description: IUPAC International Chemical Identifier (InChI) purity: type: string description: Purity specification (e.g., ≥99.5%) grade: type: string description: Product grade (e.g., ACS reagent, BioReagent, HPLC Plus) synonyms: type: array items: type: string description: Alternative names for the product physicalState: type: string enum: - solid - liquid - gas description: Physical state at room temperature packagingOptions: type: array items: $ref: '#/components/schemas/PackagingOption' PackagingOption: type: object properties: packSize: type: string description: Package size (e.g., 100g, 500mL, 1kg) packagingType: type: string description: Container type (e.g., bottle, ampule, vial) ProductSearchResults: type: object properties: results: type: array items: $ref: '#/components/schemas/Product' total: type: integer description: Total number of matching products page: type: integer pageSize: type: integer securitySchemes: ApiKeyAuth: type: apiKey in: header name: x-api-key description: Sigma-Aldrich API key for authentication externalDocs: description: Sigma-Aldrich Developer Portal url: https://www.sigmaaldrich.com/US/en/technical-documents/technical-article/chemistry/labware/sigma-aldrich-developer-portal