title: Syn- and anti-conformations of 5'-deoxy- and 5'-O-methyl-uridine 2',3'-cyclic monophosphate.
abstract: Two uridine 2',3'-cyclic monophosphate (cUMP) derivatives, 5'-deoxy (DcUMP) and 5'-O-methyl (McUMP), were studied by means of quantum chemical methods. Aqueous solvent effects were estimated based on the isodensity-surface polarized-continuum model (IPCM). Gas phase calculations revealed only slight energy differences between the syn- and anti-conformers of both compounds: the relative energies of the syn-structure are -0.9 and 0.2 kcal mol(-1) for DcUMP and McUMP, respectively. According to the results from the IPCM calculations, however, both syn-conformers become about 14 kcal mol(-1) more stable in aqueous solution than their corresponding anti-structures. Additionally, the effects of a countercation and protonation on DcUMP were studied, revealing that the syn-structure is also favored over the anti-one for these systems.
authors.affiliation: Quantum Chemistry Group, Faculty of Chemistry, A. Mickiewicz University, ul. Grunwaldzka 6, 60-780 Poznan, Poland. grabar@man.poznan.pl
authors.forename: Tomasz
authors.initials: T
authors.lastname: Grabarkiewicz
authors.forename: Marcin
authors.initials: M
authors.lastname: Hoffmann
mesh_terms: D003856:Deoxyuracil Nucleotides / Q000737:chemistry*; D005740:Gases; D008958:Models, Molecular; D008968:Molecular Conformation; D012997:Solvents; D013816:Thermodynamics; D014500:Uracil Nucleotides / Q000737:chemistry*
chemical_list: C510926:5'-deoxyuridine 2',3'-cyclic monophosphate; D003856:Deoxyuracil Nucleotides; D005740:Gases; D012997:Solvents; D014500:Uracil Nucleotides; C009806:uridine 2',3'-cyclophosphate