An efficient synthetic
route to antiviral 2′,3′-dideoxy-2′,3′-didehydro-nucleosides, such as 2′,3′-dideoxy and 2′- or 3′-deoxyribo-
nucleoside analogs, from available precursors is disclosed, with the option of introducing functionality as needed. In one embodiment, a method for the preparation of β-D and β-L-2′,3′-dideoxy-2′,3′-didehydro-nucleosides is described that includes: activating a compound of structure (1) wherein B is a
pyrimidine or
purine base and Y is O, S or CH2 with an
acyl halide of the formula X—C(═O)R1, X—C(═O)C(R1)2OC(═O)R1 or X—C(═O)OR1 (wherein X is a
halogen, and each R1 is independently
hydrogen, lower
alkyl,
alkyl,
aryl or phenyl); reducing the resulting compound with a
reducing agent to form a 2′,3′-dideoxy-2′,3′-didehydro-
nucleoside; and optionally deprotecting the
nucleoside. The haloacylation of the first step can form the 2′-acyl-3′-halonucleoside, the 3′-acyl-2′-halonucleoside, or a mixture thereof.