Generative AI for navigating synthesizable chemical space

W Wenhao Gao (Department of Chemical Engineering) S Shitong Luo (Department of Electrical Engineering and Computer Science) C Connor W. Coley

Abstract

We introduce SynFormer, a generative modeling framework designed to efficiently explore and navigate synthesizable chemical space. Unlike traditional molecular generation approaches, we generate synthetic pathways for molecules to ensure that designs are synthetically tractable. By incorporating a scalable transformer architecture and a diffusion module for building block selection, SynFormer surpasses existing models in synthesizable molecular design. We demonstrate SynFormer’s effectiveness in two key applications: 1) local chemical space exploration, where the model generates synthesizable analogs of a query molecule, and 2) global chemical space exploration, where the model aims to identify optimal molecules according to a black-box property prediction oracle. Additionally, we demonstrate the scalability of our approach via the improvement in performance as more computational resources become available. With our code and trained models openly available, we hope that SynFormer will find use across applications in drug discovery and materials science.

Article Details

Volume / Issue Vol. 122, Issue 41
Published October 14, 2025
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (3)

W

Wenhao Gao

Department of Chemical Engineering

S

Shitong Luo

Department of Electrical Engineering and Computer Science

C

Connor W. Coley