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Updated: Aug 6, 2026

Solid Phase Synthesis of a Functionalized Bis-Peptide Using "Safety Catch" Methodology
Published on: May 15, 2012
Improved synthesis of C-terminal peptide thioesters on "safety-catch" resins using LiBr/THF
1Laboratory of Organic Chemistry, Swiss Federal Institute of Technology (ETH), Universitätstrasse 16, CH-8092 Zürich, Switzerland.
Abstract:
[reaction: see text] The alkanesulfonamide "safety-catch" resin has proven useful for Fmoc-based synthesis of C-terminal peptide thioesters. We now report that the yield of isolated thioester can increase significantly when the cleavage reaction is carried out in 2 M LiBr/THF rather than DMF or THF. The largest effects are seen with problematic peptides that aggregate or form secondary structures on the resin.
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