Three Rhodamine-Based “Off–On” Chemosensors with High Selectivity and Sensitivity for Fe3+ Imaging in Living Cells

Three new rhodamine-based probes Y1–Y3 were synthesized as “off–on” chemosensors for Fe3+ imaging in living cells. The recognizing behaviors were investigated both experimentally and computationally. The crystal structure of the complex Y3-Fe3+ revealed that Fe3+ preferred to coordinate with the N atom of benzothiazole moiety rather than the O atom of carboxyl group.