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Updated: May 21, 2026

Efficient and Site-specific Antibody Labeling by Strain-promoted Azide-alkyne Cycloaddition
Published on: December 23, 2016
Site-specific modification of amino acids and peptides by aldehyde-alkyne-amine coupling under ambient aqueous
1Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H3A0B8, Canada. nicholas.uhlig@mail.mcgill.ca
Abstract:
A highly efficient method for the direct, site-specific functionalization of amino acids and peptides, under ambient conditions, is described. In aqueous, nearly solvent-free conditions, copper(I) chloride catalyzed the aldehyde-alkyne-amine (A(3)) coupling of amino acids to form dipropargylated products in moderate to excellent yields. The propargylamine functionality provides a convenient handle for further structural modifications, demonstrated by a subsequent one-pot deprotection and "click" reaction and a solution-phase peptide coupling.
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