Extended fluorescent uridine analogues: synthesis, photophysical properties and selective interaction with BSA protein†
The improvement in fluorescence properties of 2′-deoxyuridine was brought about by the introduction of (hetero)aromatic moieties at the C–5 position of uridine directly or via alkenyl/phenyl/styryl linkers to create a library of biologically useful fluorescent nucleosides. The synthesis of these extended nucleoside analogues was carried out using Suzuki–Miyaura and Heck alkenylation reactions. A comparison of their photophysical properties allowed the identification of nucleosides 1g and 1h that exhibit the highest quantum yields in an aqueous solution. Studies on the binding interaction of the most promising fluorescent analogues, 1g and 1h, with serum albumin proteins showed excellent selectivity towards BSA protein over α-amylase. Docking studies were also performed to predict the specific binding site of the nucleosides to BSA.