(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)°, respectively. An intramolecular hydrogen bond involving hydroxy O8' and carbonyl O2 helps fix the molecule in an extended arrangement with the torsion angle C5'-O1-C1-N1 between the bicyclo and pyrimidinyl moieties being 159.9 (4)°.

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