Design and synthesis of long-wavelength fluorescent boronic acid reporter compounds

Three new fluorescent probes based on the 4-amino-1,8-naphthalimide structure were synthesized, and their sugar binding properties were studied by using D-fructose, D-glucose and D-sorbitol in 0.1 M phosphate buffer at pH 7.4. All three compounds showed fluorescence intensity changes upon addition of sugars. In this series, compound 1c gave the longest emission wavelength (570 nm) and fluorescence intensity increases of up to 2.5-fold after addition Of D-fructose. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).