Peptide modification and cyclization via transition-metal catalysis.

Transition-metal catalysis has unlocked new paradigms for the late-stage modification and cyclization of peptides by harnessing the innate reactivity of proteinogenic amino acids. The field is rapidly evolving, with recent advances encompassing three fundamental areas-heteroatom couplings, decarboxylative cross-couplings, and C-H functionalizations-which have markedly extended the scope of conventional peptide modification and bioconjugation strategies. The advances outlined herein facilitate access to high-value peptide targets with promising applications in materials science and drug discovery.