Carbocyclic 2′-deoxyribonucleoside analogues: assignment of epimeric configuration and conformation by 1H nuclear magnetic resonance spectroscopy

Abstract

The determination of epimeric configuration of some novel carbocyclic 2′-deoxyribo-C-and -N-nucleosides by ¹H n.m.r. spectroscopy is described. Assignments were derived initially from ³J_HH vicinal coupling constants and then confirmed by n.O.e. difference spectroscopy. In both the C-nucleosides and N-nucleosides the β-epimers appear to adopt the same predominant conformation in solution, whereas in the α-epimers the equilibrium conformation is an average, with contribution from a number of different conformations.