title: Structure and conformation of 3'-O-acetyl-2'-deoxy-5-methoxymethyluridine.
abstract: C13H18N2O7, Mr = 314.297, triclinic, P1, a = 6.0321 (4), b = 6.775 (5), c = 9.6699 (7) A, alpha = 76.917 (6), beta = 78.871 (6), gamma = 75.344 (6) degrees, V = 368.54 A3, Z = 1, Dm = 1.43, Dx = 1.416 g cm-3, Cu K alpha radiation (Ni filtered), lambda = 1.5418 A, F(000) = 166, T = 287 K, final conventional R factor = 0.034, wR = 0.044 for 1359 reflections and 268 variables. The structure was solved using the XTAL system. The conformation of the furanose ring is best described as intermediate between 2E and 2(1)T: the pseudorotational parameters are P = 148.9 degrees and tau m = 33.4 degrees. The CH2OH, C(5'), side chain has the g+ conformation, the carbonyl bond of the 3'-acetoxy group is syn to the C(3')-O(3',1) bond on the sugar ring and the glycosidic bond conformation is anti [chi = -137.6 (3) degrees]. The methoxy group of the 5-methoxymethyl substituent is on the same side of the pyrimidine plane as O(4') of the furanose ring. Comparison with 2'-deoxy-5-methoxymethyluridine shows that intermolecular attraction have little effect on the internal conformations of the molecule in the solid state.
authors.affiliation: Department of Chemistry, University of Saskatchewan, Saskatoon, Canada.
authors.forename: J W
authors.initials: JW
authors.lastname: Quail
authors.forename: G
authors.initials: G
authors.lastname: Tourigny
authors.forename: L T
authors.initials: LT
authors.lastname: Delbaere
authors.forename: O A
authors.initials: OA
authors.lastname: el-Kabbani
authors.forename: A L
authors.initials: AL
authors.lastname: Stuart
authors.forename: S V
authors.initials: SV
authors.lastname: Gupta
mesh_terms: D000998:Antiviral Agents; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003460:Crystallization; D003857:Deoxyuridine / Q000031:analogs & derivatives / Q000138:chemical synthesis; D008968:Molecular Conformation; D015394:Molecular Structure; D011355:Prodrugs; D018139:Simplexvirus; D014961:X-Ray Diffraction
chemical_list: D000998:Antiviral Agents; D011355:Prodrugs; C062957:3'-O-acetyl-2'-deoxy-5-methoxymethyluridine; D003857:Deoxyuridine