Abstract
We report a newly discovered oxidative decarbonylation reaction of isatins that is selectively mediated by peroxynitrite (ONOO super(-)) to provide anthranilic acid derivatives. We have harnessed this rapid and selective transformation to develop two reaction-based probes, 5-fluoroisatin and 6-fluoroisatin, for the low-background readout of ONOO super(-) using super(19)F magnetic resonance spectroscopy. 5-fluoroisatin was used to non-invasively detect ONOO super(-) formation in living lung epithelial cells stimulated with interferon- gamma (IFN- gamma ).