• Open Access

Protein Modification by Strain-Promoted Alkyne–Nitrone Cycloaddition


  • This research was supported financially (in part) by the Council for Chemical Sciences of The Netherlands Organization for Scientific Research (NWO-CW, F.L.v.D.) and the National Cancer Institute of the US National Institutes of Health (Grant No. RO1 CA88986, G.-J.B.).


original image

Quicker and slicker: An efficient metal-free 1,3-dipolar cycloaddition of dibenzocyclooctynes with nitrones proceeded with rate constants of up to 39 M−1 s−1, or up to 300 times faster than similar reactions with azides. This strategy is useful for the site-specific N-terminal modification of peptides and proteins (see scheme).