Abstract: | The title compound systematic name: 5‐amino‐3‐(2‐deoxy‐β‐d ‐erythro‐pentofuranosyl)thiazolo4,5‐d]pyrimidine‐2,7‐(3H,6H)‐dione], C10H12N4O5S, exhibits a syn glycosylic bond conformation, with a torsion angle χ of 61.0 (3)°. The furanose moiety adopts the N‐type sugar pucker (3T4), with P = 33.0 (5)° and τm = 15.1 (1)°. The conformation at the exocyclic C4′—C5′ bond is +ap (trans), with the torsion angle γ = 176.71 (14)°. The extended structure is a three‐dimensional hydrogen‐bond network involving O—H...O and N—H...O hydrogen bonds. |