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Updated: Jun 21, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
O-acyl isopeptide method: efficient synthesis of isopeptide segment and application to racemization-free segment
Taku Yoshiya1, Hiroyuki Kawashima, Youhei Sohma
1Department of Medicinal Chemistry, Division of Medicinal Chemical Sciences, Center for Frontier Research in Medicinal Science, 21st Century COE program, Kyoto Pharmaceutical University, Yamashina-ku, Kyoto, 607-8412, Japan.
Abstract:
We report the establishment of the O-acyl isopeptide method-based racemization-free segment condensation reaction toward future chemical protein synthesis. Peptide segments containing C-terminal O-acyl Ser/Thr residues were successfully synthesized by use of a lower nucleophilic base cocktail for Fmoc removal, and then coupled to an amino group of a peptide-resin without side reactions or epimerization. We also succeeded in performing the segment condensation in a sequential manner and in solution phase conditions as well.
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