The preparation of novel 5-amino or 7-hydroxy substituted pyrazolo [4, 3-b] pyridine and pyrazolo [3, 4-c] pyridine acyclic C-nucleosides is described. Their synthesis was carried out by condensation of suitably substituted lithiated picolines with 2- benzyloxyethoxymethylchloride followed by pyrazole ring annulation. The compounds were evaluated for their antiviral activity against a wide panel of viruses, but were found inactive ...