Hayashi, R., et al. Tag‐Convertible Photocrosslinker with Click‐On/Off N‐Acylsulfonamide Linkage for Protein Identification. 14(18) 3145-3148

The N‐acylsulfonamide group, known as a safety‐catch linker, has been applied to photoaffinity labeling (PAL) using a cinnamate‐type photocrosslinker to improve the efficiency of PAL‐based target identification. A bioorthogonal sulfo‐click reaction was used to stably link a photocrosslinker unit with N‐acylsulfonamide linkage to produce a photoactivatable probe without any protection. In addition, the crosslinked protein was selectively isolated with a small cinnamate tag via linkage disruption upon N‐alkylation. Furthermore, the tag moiety was photochemically converted to a stable coumarin derivative by losing a water molecule, which is a useful property in MS‐based identification.