title: Structural and spectral characteristics of the cross-linked dimer derived from electrooxidation of cyclic 1,N2-propanoguanosine.
abstract: The acetaldehyde-derived cyclic propano adduct of 2'-deoxyguanosine was easily oxidized electrochemically into the cross-linked dimer as an oxidative product. The structural and spectroscopic characteristics of the dimer were investigated by MS, (1)H and (13)C-NMR, UV, and DFT calculations. The dimer formation was inferred from a molecular ionic peak of m/z 705 ([(2M-2H)+H](+), M being the molecular weight of the monomer) on the ESI-MS spectra and the chemical formula as C(28)H(36)N(10)O(12) provided by the high-resolution ESI-MS results. The C2-N5 linkage between the two monomers in the dimer was deduced from the (1)H- and (13)C-NMR spectral results. In addition, the correlations in the 2-dimensional NMR spectra (DQF-COSY and HMBC) were consistently explained by the structure of the C2-N5 cross-linked dimer. UV spectral measurements also support the C2-N5 linking in the dimer formation. The formation of the cross-link dimer as an oxidative lesion of the acetaldehyde-derived cyclic propano adduct of guanosine is expected to interfere with DNA replication and to contribute to acetaldehyde-mediated genotoxicity.
authors.affiliation: Gifu Pharmaceutical University, Gifu, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Murakami
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Esaka
authors.forename: Bunji
authors.initials: B
authors.lastname: Uno
mesh_terms: D000079:Acetaldehyde / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003432:Cross-Linking Reagents / Q000737:chemistry; D018736:DNA Adducts / Q000032:analysis / Q000138:chemical synthesis* / Q000737:chemistry*; D003849:Deoxyguanosine / Q000737:chemistry*; D019281:Dimerization; D006151:Guanosine / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D009690:Nucleic Acid Conformation; D010084:Oxidation-Reduction; D013056:Spectrophotometry, Ultraviolet / Q000379:methods
chemical_list: D003432:Cross-Linking Reagents; D018736:DNA Adducts; C559361:cyclic 1,N2-propanoguanosine; D006151:Guanosine; D003849:Deoxyguanosine; D000079:Acetaldehyde