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arXiv · 2309.02671

RLSynC: Offline-Online Reinforcement Learning for Synthon Completion

Frazier N. Baker·Ziqi Chen·Daniel Adu-Ampratwum·Xia Ning
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Abstract

Retrosynthesis is the process of determining the set of reactant molecules that can react to form a desired product. Semi-template-based retrosynthesis methods, which imitate the reverse logic of synthesis reactions, first predict the reaction centers in the products, and then complete the resulting synthons back into reactants. We develop a new offline-online reinforcement learning method RLSynC for synthon completion in semi-template-based methods. RLSynC assigns one agent to each synthon, all of which complete the synthons by conducting actions step by step in a synchronized fashion. RLSynC learns the policy from both offline training episodes and online interactions, which allows RLSynC to explore new reaction spaces. RLSynC uses a standalone forward synthesis model to evaluate the likelihood of the predicted reactants in synthesizing a product, and thus guides the action search. Our results demonstrate that RLSynC can outperform state-of-the-art synthon completion methods with improvements as high as 14.9%, highlighting its potential in synthesis planning.

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Frazier N. Baker, Ziqi Chen, Daniel Adu-Ampratwum, Xia Ning. 2023-09-06. RLSynC: Offline-Online Reinforcement Learning for Synthon Completion. https://arxiv.org/abs/2309.02671

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