What are the consequences of freezing the anomeric effect in nucleosides

The consequences of freezing the orientation of the oxygen’s lone pair orbitals —which determines whether the anomeric effect is operative or not— were studied theoretically and experimentally in two oxobicyclo-[3.1.0]hexane nucleosides (1 and 2). The results showed significant differences in the properties of these molecules, which correlated with the magnitude of the n2 → σ* delocalization.