Sugar ring conformations of guanine nucleosides by proton nuclear magnetic resonance.
Proton NMR studies at 250 MHz showed that ribofuranosyl and 2-deoxyribofuranosyl derivatives of N2-(p-n-butylphenyl)guanine (BuPG) favored the C2'-endo (S) sugar pucker and the gg exocyclic group rotamer, although less so than guanosine and 2'-deoxyguanosine themselves. The correlation calculated between C3'-endo (N) and gg conformational states in these compounds may result from destabilization of syn glycosidic bond conformers by the bulky N2 substituent. Results for a bis(ribofuranosyl) derivative of BuPG showed a strong correlation between N and gg states in both sugar rings, suggesting that both rings are anti and are stabilized by intramolecular hydrogen bonding between C3'-O and H8.
Wright
G
G
Department of Pharmacology, University of Massachusetts Medical School, Worcester 01605.
Dudycz
L
L
D006151:Guanosine / Q000031:analogs & derivatives* / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation
D006151:Guanosine