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Updated: Oct 8, 2025

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
Electrophilic Sulfonium-Promoted Peptide and Protein Amidation in Aqueous Media
Chuan Wan1, Yuan Feng1, Zhanfeng Hou2
1State Key Laboratory of Chemical Oncogenomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, P. R. China.
Abstract:
A novel amidation strategy using electrophilic sulfonium, which is soluble and stable in aqueous conditions, was developed. The sulfoniums could activate thioacid and carboxyl acid to efficiently react with amines to afford amides. This method enables applications in amidation in both aqueous media and solid-phase peptide synthesis, peptide/protein modifications, and reactive lysines of a proteome at pH 10 with activity-based protein profiling. A peptide ligand-directed labeling of the USP7-UBL2 domain was also performed using this method.
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