O-Acyl Isopeptide Method: Application of Isodipeptide Units for Ser-, Thr- and Cys-Containing Difficult Peptide Synthesis

摘要

O-Acyl isopeptide method has recently received attention as an efficient synthetic method for difficult peptides. Herein, O-acyl isodipeptide unit "Boc-Ser/Thr(Fmoc-Xaa)-OH" and S-acyl isodipeptide unit "Boc-Cys(Fmoc-Xaa)-OH" were effectively synthesized in solution-phase without epimerization, and applied to SPPS. These isodipeptide units are important building blocks to enable the routine use of the O-acyl isopeptide method.