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Updated: May 17, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
Synthesis of peptides containing C-terminal methyl esters using trityl side-chain anchoring: application to the
Veronica Diaz-Rodriguez1, Daniel G Mullen, Elena Ganusova
1Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Abstract:
A new cysteine anchoring method was developed for the synthesis of peptides containing C-terminal cysteine methyl esters. This method consists of attachment of Fmoc-Cys-OCH(3) to either 2-ClTrt-Cl or Trt-Cl resins (via the side-chain thiol) followed by preparation of the desired peptide using Fmoc-based SPPS. We applied this method to the synthesis of the mating pheromone a-factor and a 5-FAM labeled a-factor analog. The peptides were obtained with high yield and purity and were shown to be bioactive in a growth arrest assay.
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