Crystal structure of 2 `,3 `- di-o-acetyl-5 `-deoxy-5-fluorocytidine with n-h center dot center dot center dot(o,f) proton donor bifurcated and (c,n)-h center dot center dot center dot o bifurcated acceptor dual three-center hydrogen bond configurations

The title compound, C13H16O6N3F, features a central furan ring containing four carbon atom chiral centers with a 4-amino-5-fluoro-2-oxopyrimidine group, two acetyl groups and a methyl group bonded at the 2,3,4,5 positions, each in an absolute R configuration (2R, 3R, 4R, 5R). It crystallizes in the monoclinic space group C2 with unit cell parameters a = 14.5341(3), b = 7.26230(10), c = 16.2197(3) angstrom, beta = 116.607(2)degrees, Z = 4. An extensive array of intra and intermolecular hydrogen bond interactions dominate crystal packing in the unit cell highlighted by a relatively rare three-center proton-bifurcated donor N-H center dot center dot center dot(O,F) hydrogen bond interaction in cooperation with a second, (C,N)-H center dot center dot center dot O bifurcated acceptor three-center hydrogen bond in a supportive fashion. Additional weak Cg pi-ring intermolecular interactions between a fluorine atom and the 4-amino-5-fluoro-2-oxopyrimidine ring in concert with multiple donor and acceptor hydrogen bonds significantly influence the bond distances, bond angles and torsion angles of the deoxy-5-fluorocytidine group. Comparison to a MOPAC computational calculation provides support to these observations