title: 2,2'-Anhydro-1-(3',5'-di-O-acetyl-β-D-arabinofuranosyl)uracil, a cyclouridine nucleoside with a C4'-endo furanosyl conformation.
abstract: 2,2'-Anhydro-1-(3',5'-di-O-acetyl-β-D-arabinofuranosyl)uracil, C13H14N2O7, was obtained by refluxing 2',3'-O-(methoxymethylene)uridine in acetic anhydride. The structure exhibits a nearly perfect C4'-endo ((4)E) conformation. The best four-atom plane of the five-membered furanose ring is O-C-C-C, involving the C atoms of the fused five-membered oxazolidine ring, and the torsion angle is only -0.4 (2)°. The oxazolidine ring is essentially coplanar with the six-membered uracil ring [r.m.s. deviation = 0.012 (5) Å and dihedral angle = -3.2 (3)°]. The conformation at the exocyclic C-C bond is gauche-trans which is stabilized by various C-H...π and C-O...π interactions.
authors: Key Laboratory of Polymer Materials of Gansu Province, The Key Laboratory of Ecological Environment Related Polymer Materials of the Ministry of Education, Incorporated in the Local and Provincial College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, People's Republic of China. fuying@iccas.ac.cn
authors: Ying
authors: Y
authors: Fu
authors: Yin-Xia
authors: YX
authors: He
authors: Hong-Xia
authors: HX
authors: Hou
authors: Wen-Bo
authors: WB
authors: Zhu
authors: Hu-Lin
authors: HL
authors: Li
authors: Chao
authors: C
authors: Wu
authors: Fang-Yan
authors: FY
authors: Xian
mesh_terms: D001086:Arabinofuranosyluracil / Q000031:analogs & derivatives* / Q000737:chemistry; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008968:Molecular Conformation; D009705:Nucleosides / Q000737:chemistry*; D014529:Uridine / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: C580898:2,2'-anhydro-1-(3',5'-di-O-acetyl-beta-D-arabinofuranosyl)uracil; D009705:Nucleosides; D001086:Arabinofuranosyluracil; C007208:cyclouridine; D014529:Uridine