A Novel Method for the Labelling of Peptides and Proteins Through a Bioorthogonal Staudinger Reaction by Using 2-cyanoethyl Phosphoramidites

Chemoselective modification of biomolecules: The reaction between 2-cyanoethyl phosphoramidites and azides is economical and can be performed in different solvents, including aqueous buffers. The course of the reaction with azido-modified amino acids, peptides or proteins and different label molecules was followed by (31)P NMR spectroscopy.