Chloromethyl-triazole: a new motif for site-selective pseudo-acylation of proteinsElectronic supplementary information (ESI) available: Synthesis and characterisation of compounds 3b, 4b, and peptides Pep1-3. Peptide and protein alkylation procedures. See DOI: 10.1039/c6cc06801d. Primary data files can be found at http://dx.doi.org/10.7488/ds/1484

Rapid, site-selective modification of cysteine residues with chloromethyl-triazole derivatives generates pseudo-acyl sLys motifs, mimicking important post-translational modifications. Near-native biotinylation of peptide and protein substrates is shown to be site-selective and modified histone H4 retains functional activity. Chloromethyl triazoles are shown to be cysteine selective alkylation reagents for 'near-native' post-translational modification of protein and peptide substrates.