BODIPY-modified nucleosides that contain the fluorophore attached
to the 5-position of uridine via a short phenylene bridge have been
prepared and characterized by optical spectroscopy and by electrochemistry.
The target compounds were synthesized using a Pd-catalyzed cross-coupling
of 4-formyl-phenylboronic acid to 5-iodo-2′-desoxyuridine,
followed by acid-catalyzed formation of the BODIPY chromophore.
The weakly electron-donating ethyl substituents in positions 2 and
6 of the BODIPY dye, shift both the absorption and emission
properties of the corresponding modified uridines bathochromically
and alter their redox properties. In contrast, exchange of the fluoro
ligands at the boron center of the chromophores by methoxy groups
does not change the optical properties but increases the electron-rich
character of the BODIPY-modified uridines significantly.
absorption - BODIPY - cyclic voltammetry - fluorescence - nucleoside
