UniChem Compound Cross-References by InChIKey

unichem/compound-lookup

Looks up a compound by standard InChIKey (27 characters, for example BSYNRYMUTXBXSQ-UHFFFAOYSA-N for aspirin) in UniChem and returns where it is listed: the UniChem compound id, the InChI formula and layers, and one entry per source database (ChEMBL, DrugBank, PubChem, ChEBI, RCSB PDB and more) with its name, link, number of records and the first five compound ids in that database. A key UniChem does not hold returns an empty list. UniChem data, EMBL-EBI, served by Eden Engine; not an official UniChem product.

activeper callv1

Price

$0.0026 per call

You pay the price shown. If a call turns out to cost more than its quote, you pay the actual price, capped at twice the quote. No monthly minimum. Top-ups start at $0.50.

Data source

UniChem (EMBL-EBI)

Data from UniChem, EMBL-EBI (https://www.ebi.ac.uk/unichem). Cite: Chambers J et al., UniChem: a unified chemical structure cross-referencing and identifier tracking system, J Cheminform 2013. Served by Eden Engine; not an official UniChem or EMBL-EBI product.

Use it

Five steps: search, inspect, learn, run, settle. No per-tool setup; your agent reaches this tool through the meta-tools it already has.

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agent

// 1. search: find the tool
omnial_search({ query: "what you need" })

// 2. inspect: price and input schema
omnial_inspect({ tool: "unichem/compound-lookup" })

// 3. learn: read the usage guide at runtime
omnial_learn({ tool: "unichem/compound-lookup" })

// 4. run: price the exact call first, then run it
omnial_execute({ tool: "unichem/compound-lookup", input: { /* see input_schema */ }, dry_run: true })
omnial_execute({ tool: "unichem/compound-lookup", input: { /* ... */ } })

// 5. settle: the call is charged when it finishes, nothing to do

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Pricing

Every charge this tool can incur.

Charge	Price
Per call	$0.0026

Updated: Oct 25, 2026

Input and output schemas

Input schema

input_schema.json

{
  "type": "object",
  "required": [
    "inchikey"
  ],
  "properties": {
    "inchikey": {
      "type": "string",
      "pattern": "^[A-Z]{14}-[A-Z]{10}-[A-Z]$",
      "description": "Standard InChIKey, upper case, 27 characters with two hyphens, for example BSYNRYMUTXBXSQ-UHFFFAOYSA-N (aspirin) or RYYVLZVUVIJVGH-UHFFFAOYSA-N (caffeine)."
    }
  },
  "additionalProperties": false
}

Output schema

output_schema.json

{
  "type": "object",
  "required": [
    "compounds"
  ],
  "properties": {
    "notFound": {
      "type": "array",
      "items": {},
      "description": "Keys that were not found, when the service lists them."
    },
    "response": {
      "type": "string",
      "description": "Success, or Not found when the key is unknown."
    },
    "compounds": {
      "type": "array",
      "items": {
        "type": "object",
        "required": [
          "standardInchiKey",
          "sources"
        ],
        "properties": {
          "uci": {
            "type": [
              "integer",
              "null"
            ],
            "description": "UniChem compound id."
          },
          "inchi": {
            "type": [
              "object",
              "null"
            ],
            "properties": {
              "inchi": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "charge": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "hAtoms": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "formula": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "protons": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "version": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "stereoSP3": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "stereoType": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "connections": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "stereoDbond": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "isotopicAtoms": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "stereoSP3inverted": {
                "type": [
                  "string",
                  "null"
                ]
              },
              "isotopicExchangeableH": {
                "type": [
                  "string",
                  "null"
                ]
              }
            },
            "description": "InChI layers: formula, connectivity, hydrogen layer and the full InChI string.",
            "additionalProperties": true
          },
          "sources": {
            "type": [
              "array",
              "null"
            ],
            "items": {
              "type": [
                "object",
                "null"
              ],
              "properties": {
                "id": {
                  "type": [
                    "integer",
                    "null"
                  ]
                },
                "url": {
                  "type": [
                    "string",
                    "null"
                  ]
                },
                "count": {
                  "type": [
                    "integer",
                    "null"
                  ]
                },
                "longName": {
                  "type": [
                    "string",
                    "null"
                  ]
                },
                "shortName": {
                  "type": [
                    "string",
                    "null"
                  ]
                },
                "compoundIds": {
                  "type": [
                    "array",
                    "null"
                  ],
                  "items": {}
                }
              },
              "additionalProperties": true
            },
            "description": "One entry per source database: id, names, URL of its first record, record count and the first 5 compound ids."
          },
          "standardInchiKey": {
            "type": "string",
            "description": "Standard InChIKey of the compound."
          },
          "totalAssignments": {
            "type": [
              "integer",
              "null"
            ],
            "description": "Number of source records UniChem holds for the compound before grouping."
          }
        },
        "additionalProperties": true
      }
    },
    "totalCompounds": {
      "type": [
        "integer",
        "string"
      ],
      "description": "Number of compounds found."
    }
  },
  "description": "Compounds UniChem holds for the key (at most one), grouped by source; empty when the key is unknown.",
  "additionalProperties": true
}