SuFEx-Enabled High-Throughput Medicinal Chemistry

Optimization of small-molecule probes or drugs is a lengthy, challenging and resource-intensive process. Lack of automation and reliance on skilled medicinal chemists is cumbersome in both academic and industrial settings. Here, we demonstrate a high-throughput hit-to-lead process based on the biocompatible SuFEx click chemistry. A modest high-throughput screening hit against a bacterial cysteine protease SpeB was modified with a SuFExable iminosulfur oxydifluoride [RN=S(O)F2] motif, rapidly diversified into 460 analogs in overnight reactions, and the products directly screened to yield drug-like inhibitors with 300-fold higher potency. We showed that the improved molecule is drug-like and biologically active in a bacteria-host coculture. Since these reactions can be performed on a picomole scale to conserve reagents, we anticipate our methodology can accelerate the development of robust biological probes and drug candidates.