2'-Deoxyimmunosine: a thiazolo[4,5-d]pyrimidine nucleoside adopting the syn conformation

Abstract

The title compound [systematic name: 5-amino-3-(2-deoxy-beta-D-erythro-pentofuranosyl)thiazolo[4,5-d]pyrimidine-2,7-(3H,6H)-dione], C(10)H(12)N(4)O(5)S, exhibits a syn glycosylic bond conformation, with a torsion angle chi of 61.0 (3) degrees. The furanose moiety adopts the N-type sugar pucker ((3)T4), with P = 33.0 (5) degrees and tau(m) = 15.1 (1) degrees. The conformation at the exocyclic C4'-C5' bond is +ap (trans), with the torsion angle gamma = 176.71 (14) degrees. The extended structure is a three-dimensional hydrogen-bond network involving O-H...O and N-H...O hydrogen bonds.