(1′S,5′S,6′R,8′S)-1-[(6′-acetoxy-8′-hydroxy-2′-oxabicyclo[3.2.1]oct-5′-yl)oxymethyl]-N4-benzoylcytosine

The structure of the title compound, C21H23N3O7, has been determined at 193 K, The equivalent DNA-backbone torsion angles delta (O6'-C6'-C5'-C8') and gamma (C6'-C5'-C8'-O8') are 157.3(4) and 67.5(5)degrees, respectively. An intramolecular hydrogen bond involving the hydroxy O8' and carbonyl O2 atoms helps fix the molecule in an extended arrangement with the torsion angle between the bicycle and pyrimidinyl moieties (C5'-O1-C1-N1) being 159.9(4)degrees.