Synthesis and biological evaluation of 2-oxonicotinonitriles and 2-oxonicotinonitrile based nucleoside analogues

Abstract

Drug resistance and emergence of new pathogens highlight the need for developing new therapeutic agents. We focused on 2-oxonicotinonitrile (2-ONN) as derivative of the natural product 2-pyridinone.(1) Herein, we describe the synthesis of 2-ONNs bearing two aryl groups, which we coupled with organohalides, including three glycosyl bromides, to prepare the nucleoside analogues. Coupling occurred mostly at the 2-ONN ring nitrogen to give the aimed targets, and in a few cases, it happened at the 2-oxo position giving O-alkylation products. Free 2-ONNs and their acetylated nucleosides were tested against a number of viruses. The nucleoside analogue 2a(Ac) showed good anti SARS-CoV and anti influenza A (H₅N₁) activities. Additionally, 7b had good activity against Gram positive bacterium, Bacillis subtilis.

Keywords: 2-Oxonicotinonitrile; 2-Pyridinone; Antimicrobial; Antiviral; Glycosylation; Nucleoside analogues.