Structure search

Paste a SMILES and we'll rank every drug in the dataset by 2D Tanimoto similarity, using the same OpenChemLib fingerprint family that backs each drug's structural-analogs list.

298 drugs indexed · Tanimoto over 512-bit OCL substructure fingerprints · structural proximity only

POST

/api/v1/structure-search

Or try an example:

Structural proximity only. Similarity over 2D fingerprints flags molecules that look alike on paper — it is never a claim of therapeutic equivalence, bioequivalence, or shared safety profile. Two molecules can score 99% similar and behave very differently in patients.

Try the API

cURLbash

curl -X POST https://pharmacopeia.dev/api/v1/structure-search \
  -H "Content-Type: application/json" \
  -d '{"smiles": "CC(=O)NC1=CC=C(C=C1)O", "limit": 10, "threshold": 0.4}'

Note. pharmacopeia is for educational and informational use only. Structural similarity is a chemistry signal — never a clinical one. Two drugs can be structurally identical and still differ in salt form, formulation, half-life, indication, or safety profile.

Structure search

Try the API

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