Synthesis and Antiviral Activity of the α-Analogues of 1,5-Anhydrohexitol Nucleosides (1,5-Anhydro-2,3-dideoxy-<scp>d</scp>-ribohexitol Nucleosides)

1,5-Anhydro-2,3-dideoxy-D-ribohexitol nucleosides were synthesized starting from 4,6-di-O-benzyl-1,5-di-O-pivaloyl-3-deoxy-D-glucitol using a ring closure procedure. The target nucleoside adopts a (4)C(1) conformation as also demonstrated for the corresponding 1,5-anhydrohexitol nucleosides with beta-configuration of the base-substituted carbon atom. The cytosine congener demonstrated a moderate but selective activity against Herpes simplex virus types 1 and 2.