A Couple of Tripodal and Dipodal Fluorescent Sensors for Sequential “On‐Off‐On” Response to Cu 2+ and ATP/ADP Recognition in Aqueous Solution

A couple of tripodal ( 1 ) and dipodal ( 2 ) probes having tris(2‐aminoethyl) amine (tren) / N′‐Methyl‐2,2′‐diaminodiethylamine as core moiety, Boc‐L‐alanine as binding group and anthracene as signaling unit have been synthesized for the recognition of cations and anions. For 1 and 2 , their recognition behaviors towards metal ions are similar, and both of them show selective recognition towards Cu 2+ over other metal ions with a fluorescence “ switch‐off ” response. Notably, for in situ generated 1‐Cu 2+ and 2‐Cu 2+ ensembles, their responses towards polyphosphate anions are different. 1‐Cu 2+ exhibits a more significant fluorescence “ switch‐on” response towards ATP than other anionic species in aqueous solution (H 2 O/DMSO 9:1, HEPES buffer, 0.01 M, pH 7.4). While 2‐Cu 2+ shows a better sensitivity to ADP than ATP under the same conditions. Sequential “on‐off‐on” fluorescence responses of 1 and 2 to Cu 2+ and ATP/ADP are successfully applied in HeLa cells.