Kozlovskaya, Liubov I., Volok, Viktor P., Shtro, Anna A., Nikolaeva, Yulia V., Chistov, Alexey A., Matyugina, Elena S., Belyaev, Evgeny S., Jegorov, Artjom V., Snoeck, Robert, Korshun, Vladimir A., Andrei, Graciela, Osolodkin, Dmitry I., Ishmukhametov, Aydar A., and Aralov, Andrey V.
Emerging and re-emerging viruses periodically cause outbreaks and epidemics all over the world, eventually leading to global events such as the current pandemic of the novel SARS-CoV-2 coronavirus infection COVID-19. Therefore, an urgent need for novel antivirals is crystal clear. Here we present the synthesis and evaluation of an antiviral activity of phenoxazine-based nucleoside analogs divided into three groups: (1) 8-alkoxy-substituted, (2) acyclic, and (3) carbocyclic. The antiviral activity was assessed against a structurally and phylogenetically diverse panel of RNA and DNA viruses from 25 species. Four compounds (11a-c , 12c) inhibited 4 DNA/RNA viruses with EC 50 ≤ 20 μM. Toxicity of the compounds for the cell lines used for virus cultivation was negligible in most cases. In addition, previously reported and newly synthesized phenoxazine derivatives were evaluated against SARS-CoV-2, and some of them showed promising inhibition of reproduction with EC 50 values in low micromolar range, although accompanied by commensurate cytotoxicity. [Display omitted] • 8-Alkoxy-substituted, acyclic and carbocyclic phenoxazine derivatives were synthesized. • The activity was assessed against a broad panel of RNA/DNA viruses from 25 species. • Four compounds (11a-c , 12c) inhibited 4 DNA/RNA viruses with EC 50 ≤ 20 μM. • Three of them exhibited submicromolar activity against VZV. • The compounds did not show pronounced cytotoxicity against all the studied cell lines. [ABSTRACT FROM AUTHOR]