Latent fluorescence probe for in vivo imaging of glutathione

We report a latent probe (1) for biological thiols in HEPES buffer. The probe (1) was prepared from 8-formyl-7-hydroxycoumarin by the Baylis–Hillman reaction as a latent fluorescence probe to achieve high sensitivity (LOD 44 nM) and fluorescence turn-on response (F/F0 > 95) toward amino acids containing a thiol group over other various amino acids through the Michael reaction. The latent probe (1) was applied successfully to the detection of cellular GSH.