Synthesis of 6,6-Bis(O-4-arylethynylbenzoyl)-,-Trehaloses and Their Utilization as Fluorescent Probes for Cellular Imaging

A series of 6,6-bis(O-4-arylethynylbenzoyl)-,-trehaloses (aryl groups; 1a: 1-pyrenyl, 1b: 9-anthryl, 1c: phenyl) were synthesized and fully characterized. Their photophysical properties were investigated by UV/Vis/fluorescence spectroscopy, and were rationalized by TDDFT calculations. Moreover, the emission maxima of 1a and 1b in THF/H2O considerably shifted to a longer wavelength region with increasing H2O fraction owing to the formation of excimers. The pyrenyl derivative 1a was efficiently taken into HeLa CD4(+) human cervical cancer cells and emitted bright green fluorescence.