Nile Red Nucleoside:Design of a Solvatofluorochromic Nucleoside as an Indicator of Micropolarity around DNA

摘要

The fluorophore,Nile Red,effectively works as a polarity-sensitive fluorescence probe.We have designed a new nucleoside modified by Nile Red for examining the change in the polarity of the microenvironment surrounding DNA.We synthesized a Nile Red nucleoside (1),formed by replacing nucleobases with Nile Red,through the coupling of a 2-hydroxylated Nile Red derivative and 1,2-dideoxyglycan.This nucleoside showed a high solvatofluorochromicity.The fluorescence of 1 incorporated into DNA was greatly shifted to shorter wavelength by the addition of beta-cyclodextrin.The photophysical function of the Nile Red nucleoside will be a good optical indicator for monitoring the change in the micropolarity properties at a specific site on target sequences with interaction between DNA and DNA-binding molecules.