What are the consequences of freezing the anomeric effect in nucleosides?
Victor E Marquez1, Guangyu Sun, Maqbool A Siddiqui
1Laboratory of Medicinal Chemistry, Center for Cancer Research, National Cancer Institute at Frederick, National Institutes of Health, Frederick, Maryland 21702, USA. marquezv@mail.nih.gov
Abstract:
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 --> sigma * delocalization.
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