6-Aza-2'-deoxy-2'-arabinofluorouridine, a 2'-deoxyribonucleoside with an N-sugar conformation in the solid state and in solution.

In the title compound, 2-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-1,2,4-triazine-3,5(2H,4H)-dione, C(8)H(10)FN(3)O(5), the torsion angle of the N-glycosylic bond is anti [chi = -125.37 (13) degrees]. The furanose moiety adopts the N-type sugar pucker ((3)T(2)), with P = 359.2 degrees and tau(m) = 31.4 degrees. The conformation around the C4'-C5' bond is antiperiplanar (trans), with a torsion angle gamma of 177.00 (11) degrees. A network is formed via hydrogen bonds from the nucleobases to the sugar residues, as well as through hydrogen bonds between the sugar moieties.