Design, synthesis and antiviral evaluation of novel acyclic phosphonate nucleotide analogs with triazolo[4,5-]pyridine, imidazo[4,5-]pyridine and imidazo[4,5-]pyridin-2(3)-one systems.

A new series of phosphonylated triazolo[4,5-]pyridine (1-deaza-8-azapurine), imidazo[4,5-]pyridine (1-deazapurine) and imidazo[4,5-]pyridin-2(3)-one (1-deazapurin-8-one) were synthesized from 2-chloro-3-nitropyridine and selected diethyl ɷ-aminoalkylphosphonates followed by reduction of the nitro group and cyclization. In the final step ,-diethylphosphonates were transformed into the corresponding phosphonic acids. All synthesized compounds were evaluated for inhibitory activity against a broad variety of DNA and RNA viruses and their cytotoxic potencies were also established.