Highly water-soluble neutral BODIPY dyes with controllable fluorescence quantum yields

A series of novel highly water-soluble neutral BODIPY dyes have been obtained by functionalization of BODIPY dyes with branched oligo (ethylene glycol)methyl ether groups at positions 8, 2 and 6 or 4 and 4\u27. Use of an ortho-substituent group of branched oligo (ethylene glycol)methyl ether on the meso-phenyl ring of BODIPY dyes and replacement of the fluorine atoms of BODIPY dyes at positions 4 and 4\u27 with methyloxy or ethynyl subunits significantly enhance fluorescence quantum yields of BODIPY dyes. © 2011 American Chemical Society