Abstract
The synthesis and characterization of various 6-oxo-verdazyl radicals and their diamagnetic styryl radical trapping products are presented. It is shown that styryl radical trapping products derived from N-phenyl verdazyls show fluorescence whereas the N-methyl congeners are non-fluorescent. In the parent N-phenyl verdazyls fluorescence is fully quenched which renders these compounds highly valuable profluorescent radical probes.