Retrosynthetic Analysis: Predict reactants for a target product

Draw your target, then add the reagents (in SMILES) you intend to use under conditions. Leave them blank and the retrosynthesis works less well.

Output is rendered by RDKit.js. Ketcher is used only for drawing the input target.

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Model: patents, textbooks and research publications, conditioned on reaction conditions.
Beam width: 10
Show top-k: 6
All ranks come from the beam. Several may be correct — a biphenyl can be made five ways — so read the whole list.
Target product
Conditions — catalyst, base, acid, solvent
Condition presets — fills the box above
Test targets:
Target only — conditions are kept.
Built on ReactionT5v2 (Sagawa & Kojima, J. Cheminform. 2025, doi:10.1186/s13321-025-01075-4, MIT-licensed), fine-tuned on Pistachio reaction data (NextMove Software). This web interface built independently.