The chemosignaling of the oxidant Oxone by selective desulfurization of a thioamide was investigated. Pyrene-thioamide was efficiently converted to its amide analogue by reaction with Oxone, resulting in a pronounced fluorescent turn-on type signaling. Selective signaling of Oxone in aqueous solution was possible in the presence of representative alkali and alkaline earth metal ions, as well as common anions.