/pubchem/compounds/search

POST /api/pubchem/compounds/search

Price: 1 credit

Search PubChem compounds by name, SMILES, or InChIKey

How to use it

Search compounds on PubChem. Provide a chemical name, a SMILES string, or an InChIKey in 'query' and set 'namespace' accordingly. For name queries, set 'match' to 'exact' for the single best match or 'word' to find all compounds whose name contains the query word. Returns matching compounds with full chemical data (formula, weight, SMILES, InChI/InChIKey, computed descriptors, description, synonyms).

Parameters

• access-token string required

Request body

• timeout integer — Max scrapping execution timeout (in seconds) (default: 300; min: 20; max: 1500)
• query string required — Search query — a chemical name, SMILES string, or InChIKey (examples: "aspirin", "CC(=O)OC1=CC=CC=C1C(=O)O", "BSYNRYMUTXBXSQ-UHFFFAOYSA-N"; minLength: 1)
• namespace string — Type of the query value (default: "name"; one of: "name", "smiles", "inchikey")
• match string — Name matching mode (applies only when namespace is 'name'): 'exact' returns the single best-matching compound, 'word' returns all compounds whose name contains the query word (default: "exact"; one of: "exact", "word")
• count integer required — Max result count (min: 1)

Response

• @type string (default: "PubchemCompound")
• id integer required
• url string required
• iupac_name string nullable
• molecular_formula string nullable
• molecular_weight string nullable
• smiles string nullable
• connectivity_smiles string nullable
• inchi string nullable
• inchi_key string nullable
• xlogp number nullable
• tpsa number nullable
• complexity number nullable
• charge integer nullable
• exact_mass string nullable
• monoisotopic_mass string nullable
• h_bond_donor_count integer nullable
• h_bond_acceptor_count integer nullable
• rotatable_bond_count integer nullable
• heavy_atom_count integer nullable
• covalent_unit_count integer nullable
• atom_stereo_count integer nullable
• defined_atom_stereo_count integer nullable
• undefined_atom_stereo_count integer nullable
• bond_stereo_count integer nullable
• defined_bond_stereo_count integer nullable
• volume_3d number nullable
• conformer_count_3d integer nullable
• literature_count integer nullable
• patent_count integer nullable
• patent_family_count integer nullable
• annotation_type_count integer nullable
• description string nullable
• description_source string nullable
• description_url string nullable
• synonyms array (default: [])

Errors

• 422 — The request body did not validate Check the fields against this schema. A URN with the wrong prefix is the most common cause.
• 408 — The request ran past its time limit Raise `timeout` in the request body, up to the maximum this endpoint documents. Lowering `count` or turning off the `with_*` flags also helps, because less work finishes sooner.
• 412 — No matching compound found Retrying will not help: either the entity does not exist, or the input points at a different one.
• 429 — Too many requests: a rate limit or a usage window is exhausted When the response carries an X-Retry-After header, wait that many seconds and retry: the same number is in the body as `detail.retry_after`, and the limit clears once that window passes. The message in the body names the limit that was hit.
• 500 — Something broke on our side Retrying will not help. If it keeps happening, send us the X-Request-ID from the response headers.
• 529 — Rate limit reached, or the endpoint is overloaded Wait at least 30 seconds, then retry.

Response headers

• X-Error — Error message text (present only on error)
• X-Request-ID — Unique request identifier
• X-Execution-Time — Execution time in seconds
• X-Result-Count — How many records the body carries. 0 means an empty result, which is a normal answer and not by itself an error. A non-zero count can come back together with X-Error when the failure happened partway through — read this header and X-Error independently.
• X-Total-Available-Results — How many records exist for this query, when the endpoint can say. On a `dry_run` request this is the answer and the body is empty. It saturates: the endpoint's documented maximum means 'at least that many', any smaller number is exact.
• X-Warning — Present when the request body carried keys this endpoint does not document. They were ignored, so any filter you meant to apply through them did not apply. Check the spelling against this schema and retry.
• X-Retry-After — Seconds to wait before retrying. Present only on 429.