How to Look Up Chemical Compounds with Claude
Look up chemical compound properties with Claude and ToolRouter. Molecular data, SMILES, and CAS numbers from PubChem.
Tool
Claude combines compound lookup results with explanations of what the properties mean — why a particular molecular weight matters for a synthesis, what a SMILES string encodes structurally, or how two similar compounds differ in their properties. It bridges the gap between raw data and chemical understanding.
Connect ToolRouter to Claude
1Open connector settings Open Settings
2Add a custom connector with these details
Name
ToolRouterURL
https://api.toolrouter.com/mcp3Let Claude set you up Open Claude
Steps
Once connected (see setup above), use the Chemistry Lookup tool:
- Ask: "Look up aspirin using chemistry-lookup"
- Claude returns molecular formula, weight, SMILES, and structural identifiers
- Ask: "What does this molecular formula tell us about aspirin's structure?"
- Request: "Find similar compounds to aspirin using chemistry-lookup"
Example Prompt
Try this with Claude using the Chemistry Lookup tool
Look up ibuprofen using chemistry-lookup. Return the molecular formula, weight, IUPAC name, and CAS number. Then explain what the structure tells us about how it behaves as an anti-inflammatory.
Tips
- Use the IUPAC name lookup when you only have a common trade name for a compound
- Ask Claude to explain the significance of specific structural features (functional groups, ring systems)
- Search by CAS number for unambiguous identification when names are ambiguous