Related Experiment Video
Updated: May 6, 2026

Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
Rapid additive-free selenocystine-selenoester peptide ligation
Nicholas J Mitchell1, Lara R Malins1, Xuyu Liu1
1School of Chemistry, The University of Sydney , Sydney, NSW 2006, Australia.
Abstract:
We describe an unprecedented reaction between peptide selenoesters and peptide dimers bearing N-terminal selenocystine that proceeds in aqueous buffer to afford native amide bonds without the use of additives. The selenocystine-selenoester ligations are complete in minutes, even at sterically hindered junctions, and can be used in concert with one-pot deselenization chemistry. Various pathways for the transformation are proposed and probed through a combination of experimental and computational studies. Our new reaction manifold is also showcased in the total synthesis of two proteins.
Related Concept Videos
Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition)
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...
Bioavailability Enhancement: Drug Stability Enhancement and GI Retention

