title: Strain-promoted sydnone bicyclo-[6.1.0]-nonyne cycloaddition†Electronic supplementary information (ESI) available: Full experimental details,1H/13C NMR spectral data, protein synthesis and purification. See DOI: 10.1039/c3sc53332h.
abstract: The discovery and exploration of bioorthogonal chemical reactions and the biosynthetic incorporation of their components into biomolecules for specific labelling is an important challenge. Here we describe the reaction of a phenyl sydnone 1,3-dipole with a bicyclononyne dipolarophile. This strain-promoted reaction proceeds without transition metal catalysis in aqueous buffer, at physiological temperature, and pressure with a rate comparable to that of other bioorthogonal reactions. We demonstrate the quantitative and specific labelling of a genetically encoded bicyclononyne with a sydnone fluorophore conjugate, demonstrating the utility of this approach for bioorthogonal protein labelling.
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge Biomedical Campus , Cambridge , CB2 0QH , UK . Email: chin@mrc-lmb.cam.ac.uk ; http://www.2.mrc-lmb.cam.ac.uk/ccsb/
authors.forename: Stephen
authors.initials: S
authors.lastname: Wallace
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge Biomedical Campus , Cambridge , CB2 0QH , UK . Email: chin@mrc-lmb.cam.ac.uk ; http://www.2.mrc-lmb.cam.ac.uk/ccsb/
authors.forename: Jason W
authors.initials: JW
authors.lastname: Chin