Synthesis and Absolute Configuration of Novel <i>N</i>,<i>O</i>-Psiconucleosides Using (<i>R</i>)-<i>N</i>-Phenylpantolactam as a Resolution Agent

A series of novel N,O-psiconucleosides has been prepared in both enantiomeric forms by resolution of an advanced racemic synthetic intermediate using (R)-N-phenylpantolactam as a chiral resolution agent. The absolute configuration of all of these compounds has been unequivocally established by chemical correlation with the novel (R)- or (S)-1-methyl-5-phenylpyrrolidine-2,3-dione, prepared from the known (R)- and (S)-1-methyl-5-phenylpyrrolidin-2-one, respectively.