Synthesis and Evaluation of Thiol Probes using the 6,7-dimethoxyquinoxalin-2(1H)-one fluorophore

Abstract

3-Substituted quinoxalin-2(1 H)-ones, 7 and 10, were prepared as candidate fluorescent probes for thiols and then reacted with representative thiols to give sulfides, 11–17, whose fluorescence was studied.

Quinoxalin‐2(1H)‐ones: Chemical Synthesis, Fluorescence Properties and Applications

“…In 2000, Parrick reported the first fluorescent probes based on the quinoxalin‐2(1 H )‐one scaffold for the specific detection of thiols [70] . The well‐established thiol‐reactive group, maleimide [71] or iodoacetamide, was linked at the position 3 of the quinoxalin‐2(1H)‐one through a 4‐aminostyryl moiety.…”

“…In 2000, Parrick reported the first fluorescent probes based on the quinoxalin-2(1H)-one scaffold for the specific detection of thiols. [70] The well-established thiol-reactive group, maleimide [71] or iodoacetamide, was linked at the position 3 of the quinoxalin-2(1H)-one through a 4-aminostyryl moiety. No or moderate increase in the fluorescence quantum yield was observed with probe 173 upon the addition of thiol either in MeOH (from 0.25 to 0.24-0.29) or DCM (from 0.25 to 0.50-0.54), respectively (Scheme 26).…”