Fluorescence sensing of Cu(II) based on trisphaeridine derivatives

The design, synthesis, and ion-sensing properties of new 7,11-diaryltrisphaeridines are described. 2-Thiophenyl and 2-furanyl derivatives behave as highly selective fluorescence chemosensors for Cu2+ cations, with limits of detection (LOD) of 3.8 and 12.9 μM, respectively, i.e. below the toxic level of Cu2+ (ca. 20 μM); while the presence of 2-methoxyphenyl groups favors the selective detection of Cu2+ and lowers the LOD to 1.1 μM.