Circular dichroism and anomeric configuration assignment of benzimidazole C-nucleoside analogs

► Acid catalyzed dehydrative cyclization of 2-(L-arabino-tetritol-1-yl)benzimidazole gave 2-(β-L-erythrofuranosyl)benzimidazole ► The dehydrative cyclization took place with SN2 mechanism without inversion at C-1′. ► A correlation between the stereochemistry at the carbon atom α to the benzimidazole base moiety and the sign of the Cotton effect was obtained. ► This correlation is used for the assignment of the anomeric configuration. ► ECD proved to be a reliable tool for anomeric assignment.