Solution conformations of two naturally occurring RNA nucleosides: 3-Methyluridine and 3-methylpseudouridine Original Research Article

The conformations of 3-methyluridine and 3-methylpseudouridine are determined using a combination of sugar proton coupling constants from 1D NMR spectra and 1D NOE difference spectroscopy. Both C2′-endo and C3′-endo conformations are observed for 3-methyluridine (59:41, 37 °C, D2O) and 3-methylpseudouridine (51:49, 37 °C, D2O). 3-Methyluridine preferentially adopts an anti conformation in solution, whereas 3-methylpseudouridine is primarily in a syn conformation. anti/syn-Relationships are deduced by 1D NOE difference spectroscopy.