Nucleoside analogues. Synthesis of 2′,3′-dideoxy and 2′,3′-unsaturated ribofuranonucleosides of 5,6-dichloro-2-mercaptobenzimidazole as potential antiviral agents
Novel benzimidazole nucleoside derivatives structurally related to 5,6-dichloro-1-(β-D-ribofuranosyl)benzimidazole (DRB) and to tetrahydroimidazobenzodiazepinethione (TIBO) compounds have been synthesized and their antiviral properties examined. The 2′,3′-unsaturated nucleoside was obtained following chemical transformations of the corresponding β-D-ribofuranonucleoside, whereas the 2′,3′-dideoxynucleoside was synthesized by a glycosylation reaction between a suitably protected 2,3-dideoxy-D-glycero-pentofuranose and silylated 5,6-dichloro-2-mercaptobenzimidazole. The prepared compounds were tested for their activity against HIV and against a variety of RNA and DNA viruses, but they did not show significant antiviral activity.