Syntheses and photophysical properties of furanouridines and dabcyl containing nucleosides

Master5-Aryl-2´-deoxyfuranouridine derivatives containing various aryl groups were synthesized through Cu(I) catalyzed intramolecular cyclizations. Furano-dUs family thoroughly characterized by using UV/vis and fluorescence spectroscopy. Time-dependent density functional theory calculations were done to predict properties of furano-dUs family. Dimethyl amino group contained furano-dUs shows environmental sensitive properties. Another furano-dUs show high quantum yield and brightness, and results suggesting future applicability as fluorescent nucleobase analogues. 5-(4-Ethynyldabcyl)-2'-deoxyuridine(DABdU), C25H25N5O5, was synthesized by Sonogashira coupling. Non-planar geometry is observed between uridine group and dabcyl group, and the azo bond shows trans conformation. In the crystal, molecules are linked by N—H···O wobble-like base pairing and O—H···O intermolecular hydrogen bonding interactions. DABdU shows broad UV absorbance and non-emissive fluorescence spectra. In duplex fluorescent probes, DABdU-pydU systems show higher quenching abilities than pydU-pydU systems