Papers › Chemformer: a pre-trained transformer for computational chemistry

Chemformer: a pre-trained transformer for computational chemistry

31 Jan 2022Machine Learning: Science and Technology 2022 1archive 2025-07-28

Ross Irwin, Spyridon Dimitriadis, Jiazhen He, Esben Jannik Bjerrum

Transformer models coupled with a simplified molecular line entry system (SMILES) have recently proven to be a powerful combination for solving challenges in cheminformatics. These models, however, are often developed specifically for a single application and can be very resource-intensive to train. In this work we present the Chemformer model—a Transformer-based model which can be quickly applied to both sequence-to-sequence and discriminative cheminformatics tasks. Additionally, we show that self-supervised pre-training can improve performance and significantly speed up convergence on downstream tasks. On direct synthesis and retrosynthesis prediction benchmark datasets we publish state-of-the-art results for top-1 accuracy. We also improve on existing approaches for a molecular optimisation task and show that Chemformer can optimise on multiple discriminative tasks simultaneously. Models, datasets and code will be made available after publication.

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Code

MolecularAI/Chemformer pytorchApache-2.0 report

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Tasks

Computational chemistryRetrosynthesisSingle-step retrosynthesis

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Single-step retrosynthesis USPTO-50k Chemformer-Large (reaction class unknown) Top-1 accuracy 54.3 #17 of 35 Archive leaderboard report
Single-step retrosynthesis USPTO-50k Chemformer-Large (reaction class unknown) Top-10 accuracy 63.0 #17 of 35 Archive leaderboard report
Single-step retrosynthesis USPTO-50k Chemformer-Large (reaction class unknown) Top-5 accuracy 62.3 #17 of 35 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

SPEED

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