Synthesis of the chiral acyclonucleoside antiherpetic agent (S)-9-(2,3-dihydroxy-1-propoxymethyl)guanine

A new synthesis of the potential antiviral agent, (S)-9-(2,3-dihydroxy-1-propoxymethyl)guanine is described, starting from the readily available methyl 2,3,4-tri-$\text{O}$-benzyl-α-(=D)-glucopyranoside. The sequence utilizes the absolute configuration defined by carbons 4, 5 and 6 of the (=D)-glucose ring and provides a ready synthesis of the single enantiomer without recourse to many chromatographic separations.