Synthesis of Nucleosides and Non-nucleosides Based 4,6-disubstituted-2-oxo-dihydropyridine-3-carbonitriles as Antiviral Agents.

Abstract

Viral diseases are considered main threats that face the humanity worldwide. The emergence of new viruses like influenza viruses emphasizes the significance of designing novel antiviral drugs. The aim of this work is to synthesize a new set of nucleoside and non-nucleoside cyanopyridine, characterized and evaluated for their in vitro antiviral properties against various strains. More of the compounds showed variable antiviral potential against a panel of eighteen DNA and RNA viruses. The screening data suggested that the order of activity of the active compounds are in the order of O-glycosyl > O-alkyl > N-alkyl > S-alkyl derivatives. In addition, the 4-fluoro substituted compounds are more effective among the O- and N-alkyl analogs, whereas remarkable antiviral activity was ascribed to the methoxylated O-glycosyl derivatives. Most of the active compounds proved to be more selective towards the inhibition of the replication of DNA rather than the RNA-viruses. The analogs 1a, 2a, 12b, 14b and 16b possessed broad spectrum and noticeable antiviral potential against most of the tested DNA- and RNA-viruses (EC50 ≈ 0.8-20 µM), accompanied with considerably low cytotoxic margin (MCC ≈ 4-20 µM), and comparable with reference standard antiviral agents.