Nucleosides 8 [18]: Ribosylation of fused quinazolines-synthesis of new [1,2,4]triazolo[5,1-b]- and [1,2,4]triazino[3,2-b]quinazoline nucleosides of fluorescence interest

[1,2,4]triazolo[5,1-b]- and [1,2,4]triazino[3,2-b] quinazolines have been ribosylated by coupling with 1-o-acetyl-2,3,5-tri-o-benzoyl-β-d- ribofuranose and by using the silylation method,followed by debenzoylation by methanolic sodium methoxide to afford the corresponding free n-nucleosides. nucleosides obtained have been identified by their spectral analysis. from the uv-visible and fluorescence studies of some nucleosides synthesized,it is found that they have fluorescence properties. © 2013 laila mohamed break et al.