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Updated: Aug 10, 2026

Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
Thioether side chain cyclization for helical peptide formation: inhibitors of estrogen receptor-coactivator
A K Galande1, K S Bramlett, T P Burris
1Department of Chemistry and the Institute for Molecular Diversity and Drug Design, University of Louisville, Louisville, KY, USA.
Abstract:
Cystine, lanthionine, and cystathionine containing cyclic peptides incorporating the signature nuclear receptor (NR) box (LXXLL) motif have been synthesized and the abilities of these peptides to inhibit estrogen receptor (ER)-coactivator interactions have been determined. We found that helicity of these peptides directly correlated with their bioactivity. Cystathionine proved to be a redox-stable, isosteric replacement for the cystine disulfide. Cystathionine containing peptide 3 showed higher helical character and a lower inhibition constant (Ki, 7 nm) when compared with its cystine counterpart.
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