| Abstract: | The title compound systematic name: (1S,3S,4R,7S)‐3‐(4‐amino‐1H‐pyrazolo3,4‐d]pyrimidin‐1‐yl)‐1‐hydroxymethyl‐2,5‐dioxabicyclo2.2.1]heptan‐7‐ol], C11H13N5O4, belongs to a family of nucleosides with modifications in both the sugar and nucleobase moieties: these modifications are known to increase the thermodynamic stability of DNA and RNA duplexes. There are two symmetry‐independent molecules in the asymmetric unit that differ significantly in conformation, and both exhibit a high‐anti conformation about the N‐glycosidic bond, with χ torsion angles of ?85.4 (3) and ?87.4 (3)°. The sugar C atom attached to the nucleobase N atom is ?0.201 (4) and 0.209 (4) Å from the 8‐aza‐7‐deazaadenine skeleton plane in the two molecules. The molecules are assembled into layers via hydrogen bonds and π–π stacking interactions between the modified nucleobases. |
