Epimerization-Free Synthesis of Azo-Substituted Di- and Tripeptides by Cross-Coupling of O-Triflated Derivatives and Diazenyl Anion Equivalents

Abstract

Based on our previous work, a method for the synthesis of azo-substituted small peptides through C(sp²)–N(sp²) cross-coupling between triflated peptide derivatives and N-aryl-N′-trimethylsilyldiazenes is reported. The peptide-substituted azobenzene products are formed in acceptable yields with full stereoretention at the asymmetrically substituted carbon atom despite the basic reaction medium.

Keywords

Azobenzenes - C–N cross-coupling - Late-stage peptide modification - Palladium - Photoswitchable peptides

Publication History

Received: 01 November 2025

Accepted after revision: 26 November 2025

Accepted Manuscript online:
26 November 2025

Article published online:
14 January 2026

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