Caged fluorophore: We report the first caging strategy for rosamine fluorophores based on a uniqueintramolecularcarbon–carbonspirocyclization. The new class of carbon–carbon spirocyclic caged probes exhibit several significant advantages over the traditional nitrobenzyl‐caged xanthene probes and can be employed for spatially controlled fluorescence imaging of living cells (see graphic).
A fluorescence turn-on probe for Cu2+ based on the novel copper-mediated dihydrorosamine oxidation reaction has been constructed and employed in the detection of Cu2+ in water, new born calf serum, and living cells, and the new copper-mediated dihydrorosamine oxidation reaction likely proceeds by a copper redox mechanism.