1 research outputs found
Design of “Click” Fluorescent Labeled 2′-deoxyuridines via C5-[4-(2-Propynyl(methyl)amino)]phenyl Acetylene as a Universal Linker: Synthesis, Photophysical Properties, and Interaction with BSA
Microenvironment-sensitive
fluorescent nucleosides present attractive
advantages over single-emitting dyes for sensing inter-biomolecular
interactions involving DNA. Herein, we report the rational design
and synthesis of triazolyl push–pull fluorophore-labeled uridines
via the intermediacy of C5-[4-(2-propynylÂ(methyl)Âamino)]Âphenyl acetylene
as a universal linker. The synthesized nucleosides showed interesting
solvatochromic characteristic and/or intramolecular charge transfer
(ICT) features. A few of them also exhibited dual-emitting characteristics
evidencing our designing concept. The HOMO–LUMO distribution
showed that the emissive states of these nucleosides were characterized
with more significant electron redistribution between the C5-[4-(2-propynylÂ(methyl)Âamino)]Âphenyl
triazolyl donor moiety and the aromatic chromophores linked to it,
leading to modulated emission property. The solvent polarity sensitivity
of these nucleosides was also tested. The synthesized triazolyl benzonitrile
(<b>10C</b>), naphthyl (<b>10E</b>), and pyrenyl (<b>10G</b>) nucleosides were found to exhibit interesting ICT and
dual (LE/ICT) emission properties. The dual-emitting pyrenyl nucleoside
maintained a good ratiometric response in the BSA protein microenvironment,
enabling the switch-on ratiometric sensing of BSA as the only protein
biomolecule. Thus, it is expected that the new fluorescent nucleoside
analogues would be useful in designing DNA probes for nucleic acid
analysis or studying DNA–protein interactions via a drastic
change in fluorescence response due to a change in micropolarity