Fragmentation-Rearrangement of Peptide Backbones Mediated by the Air Pollutant NO2 (.).

The fragmentation-rearrangement of peptide backbones mediated by nitrogen dioxide, NO2 (.) , was explored using di-, tri-, and tetrapeptides 8-18 as model systems. The reaction, which is initiated through nonradical N-nitrosation of the peptide bond, shortens the peptide chain by the expulsion of one amino acid moiety with simultaneous fusion of the remaining molecular termini through formation of a new peptide bond.