Details of the synthesis of<unk>  were first published by scientists from the University at Buffalo. :650px In the first step shown, 2,6-dichloropurine was alkylated with 1-benzoyloxy-2-chloromethoxyethane. The chlorine group at the 6-position of the heterocyclic ring is more reactive than the chlorine at the 2-position, hence it can be selectively replaced by an amino group, which was then converted to an amide using nitrous acid. Finally, the remaining chlorine was replaced by the amino group of<unk>  using ammonia in methanol. This synthesis and other methods for preparing the compound have been reviewed.
Aciclovir
Penciclovir
Valganciclovir
Famciclovir
Ganciclovir
Alcaftadine
Benzylpenicillin
Amantadine