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Updated: Jul 16, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
Synthesis of amino acid-derived cyclic acyl amidines for use in beta-strand peptidomimetics
Ming C Hammond1, Paul A Bartlett
1Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley, California 94720, USA.
Abstract:
The acyl amidine represented by the 4,5-dihydro-2(3H)-pyrazinone ring system 2 is isosteric to the vinylogous amide of the 1,2-dihydro-3(6H)-pyridinone 1, but its assembly from separate amine and amide components enables ready incorporation of an amino acid side chain with correct regio- and stereochemistry. beta-Strand peptidomimetics incorporating amino acid analogues based on 2 have recently been shown to be potent, protease-resistant ligands to a PDZ protein-interaction domain. Two routes to the protected dipeptide analogue 3 are described.
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