A Highly Selective Fluorescent Probe for Thiophenols

A rapid response to thiophenols is obtained with probe 1 (see scheme), which induces a significant (>50-fold) fluorescence enhancement as a result of cleavage of the electron-withdrawing moiety, thus generating strongly fluorescent molecule 2. No fluorescence is obtained with aliphatic thiols, including cysteine and glutathione, or other nucleophiles.