organic compounds
The five-membered furanose ring of three fluoro- or chloro-substituted 1′-deoxy-1′-phenyl-β-D-ribofuranoses has a conformation between a C2′-endo,C3′-exo twist and a C2′-endo envelope. The ribofuranose groups are connected by O—HO hydrogen bonds to symmetry-related molecules to form layers. The orientation of the benzene ring is independent of the substitution pattern of the ring and depends mainly on crystal-packing effects.