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Updated: May 22, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
Parallel synthesis of peptide-like macrocycles containing imidazole-4,5-dicarboxylic acid
Zhigang Xu1, Kraig A Wheeler, Paul W Baures
1Department of Pharmacology and Toxicology, The University of Arizona, Tucson, AZ 85724, USA.
Abstract:
We prepared a series of peptide-like 14-membered macrocycles containing an imidazole-4,5-dicarboxylic acid scaffold by using known coupling reagents and protecting group strategies. Yields of the purified macrocycles were poor on average, yet seemingly independent of amino acid substitution or stereochemistry. The macrocycles retain some level of conformational variability as observed by both molecular modeling and X-ray crystallography. These macrocycles represent a new class of structures for further development and for future application in high-throughput screening against a variety of biological targets.
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