Nickel(II)-Promoted Amide N-H Arylation of Pyroglutamate-Histidine with Arylboronic Acid Reagents.

Small and simple bioorthogonal reactive handles that can be readily encoded by natural processes are important for bioconjugation. A rapid nickel-promoted N-H arylation of pyroglutamate-histidine sequences with 2-nitroarylboronic acids proceeds under mild aqueous conditions. Chemoselective activation of a lactam amide N-H within a peptide or protein provides a new approach to selective conjugation in polyamide structures.