Structural Interpretation of J-coupling Constants Calculated in Guanosine and Deoxy-Guanosine: Influence of Sugar-Phosphate-like Backbone Conformation, Sugar Pucker and Solvent Environment

Zuzana Vokáčová^1,2, F. Matthias Bickelhaupt³, Jiří Šponer⁴ and Vladimír Sychrovský¹

¹Institute of Organic Chemistry and Biochemistry, v.v.i., Academy of Sciences of the Czech Republic, Flemingovo sq. 2, 166 10 Prague, Czech Republic, ²Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 121 16 Praha 2, Czech Republic, ³Theoretical Chemistry and Amsterdam Center for Multiscale Modeling, Scheikundig Laboratorium der Vrije Universiteit, De Boelelaan 1083, NL-1081 HV Amsterdam, The Netherlands, ⁴Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, 612 65 Brno, Czech Republic

The relationship between the the glycosidic torsion angle c, the three-bond couplings ³J(C8-H1’) and ³J(C4-H1’), and the four one-bond couplings ¹J(C8-H8), ¹J(C1’-H1’), ¹J(C2’-H2’) and ¹J(C2’-H2’2) in deoxyguanosine and the three one-bond couplings ¹J(C8-H8), ¹J(C1’-H1’) and ¹J(C2’-H2’) for guanosine has been analyzed using density functional theory - B3LYP /6-31G**. The influence of the backbone conformation, sugar composition and the sugar pucker, and molecular environment including water solvation has been also considered.

Figure 1: Numbering of atoms and definition of torsion angles in deoxy-Guanosine.

Acknowledgements: This work was supported by the Grant Agency of the Czech Academy of (grants no. IAA400550701), by the Grant Agency of Charles University (grant GAUK nr. 58708), by the Netherlands Organization for Scientific Research (NWO-CW), and by the National Research School Combination - Catalysis (NRSC-C)