Regioselective alkylation of guanines using 2-acetoxytetrahydrofurans

Abstract Reaction of silylated guanine derivatives with 2-acetoxy-4-benzoyloxymethyltetrahydrofuran in DMF or NMP resulted in selective N-9 alkylation. This was used as the basis for a regioselective synthesis of the anti-viral agents famciclovir and penciclovir.