The para-sulfonamide analogue (p-TsABDI) of a green fluorescent protein (GFP) chromophore was synthesized to mimic the GFP chromophore. Its S1 excited-state pKa∗ value in dimethylsulfoxide (DMSO) is -1.5, which is strong enough to partially protonate dipolar aprotic solvents and causes excited-state proton transfer (ESPT), so it can partially mimic the GFP chromophore to further study the ESPT-related photophysics and the blinking phenomenon of GFP. In comparison with 8-hydroxypyrene-1,3,6-trisulfonate (HPTS) (pKa = 7.4, pKa∗ = 1.3 in water), p-TsABDI (pKa = 6.7, pKa∗ = -1.5 in DMSO) is a better photoacid for pH-jump studies.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry