Abstract: 2-Ethoxycarbonyl-3,4-tetramethylenepyrrole prepared from cyclohexene through an improved two-step procedure was treated with excess lithium aluminum hydride at high temperature to give 2-methyl-3,4-tetramethylenepyrrole. Further condensation with protected 4-formylphenylboronic acid in the presence of trifluoroacetic acid as catalyst, followed by oxidation with 2,3-dichloro-5,6-dicyanobenzoquinone(DDQ) and treatment with triethylamine and boron trifluoride etherate， gives a novel exocyclic ring-fused boron-dipyrromethene(BDP) dye derivative substituted with phenylboronic ester subunit at the meso-position. The UV-Vis absorption titration and fluorescence titration measurements for BDP dye derivative were carried out to examine its responsibility to D-fructose, D-galactose, and D-glucose at specific pH. The influence of covalent interactions of BDP dye derivative with monosaccharides on its spectroscopic properties can be selectively recognized by both absorption and fluorescence spectra. By the nonlinear curve-fitting analysis of the fluorescence titration data, the association constants Ks of BDP derivative 1 with monosaccharide such as D-fructose, D-galactose, and D-glucose are 1045, 445 and 130 L/mol, respectively. Thus BDP derivative 1 can be used as a sensitive and selective fluorescent probe for monosaccharides. Moreover, the sensing mechanism of the fluorescent probe was also preliminarily discussed.

Key words: boron dipyrromethene dye, fluorescent probe, monosaccharide, fused exocyclic rings, phenylboronic acid