Synthesis and antiviral activity of 1,2,3-triazole glycosides based substituted pyridine via click cycloaddition

Novel conjugates of substituted pyridine and carbohydrate moieties linked by 1,2,3-triazoles were synthesized. The propargyl group was introduced by O-propargylation of pyridone derivatives. Attachment of carbohydrate molecules to the substituted pyridine core was performed by Cu-catalyzed cycloaddition of propargyl sugars with azidoethoxypyridine derivative or azido-sugars with substituted (propargyl)oxypyridines which afforded the corresponding 1,2,3-triazoles in high yields. Antiviral activity of synthesized compounds was studied against H5N1 influenza virus and triazolyl glycoside 7 demonstrated high activity in addition to its low toxicity. The effect of attachment of glycosyl triazole moieties to pyridinyl system was studied, in SAR correlation, which has been found to enhance antiviral activity.