Synthesis of fluorogenic arylureas and amides and their interaction with amines: A competition between turn-on fluorescence and organic radicals on theway to a smart label for fish freshness

Abstract

We describe the synthesis of fluorogenic arylureas and amides and their interaction with primary or secondary amines under air and light in organic-aqueous mixtures to give rise to a new class of persistent organic radicals, described on the basis of their electron paramagnetic resonance (EPR), as well as UV-vis, fluorescence, NMR, and quantum mechanics calculations, and their prospective use as multi-signal reporters in a smart label for fish freshness.