meso-C6F5 substituted BODIPYs with distinctive spectroscopic properties and their application for bioimaging in living cells

A series of meso-C6F5 BODIYs have been successfully synthesized and characterized. Some of them displayed excellent spectroscopic properties, such as relatively large Stokes shift, high fluorescence quantum yield, far-red or near infrared region (NIR) emission, and good photostability. In particular, the dye functionalized with oligo(ethylene glycol) ether-phenyl groups at the 3,5-position of BODIPY core became water-soluble and its emission located in the NIR region with large Stokes shift. Time-dependent density functional theory calculations were conducted to understand the structure-optical properties relationship. Furthermore, cell staining tests demonstrated that the meso-C6F5 BODPY derivative with oligo(ethylene glycol) ether-phenyl group was membrane permeable and selectively stained cytosol in living cells.