Synonyms: Aciclovir Imp. A (EP), Valaciclovir Hydrochloride Imp. I (EP), Valaciclovir Imp. I (EP), Acyclovir USP Related Compound A, Acyclovir USP RC A, 2-[(2-Amino-6-oxo-1,6-dihydro-9H-purin-9-yl)methoxy]ethyl Acetate, Valaciclovir Hydrochloride Anhydrous Imp. I (EP), 598U75, USP Acyclovir Related Compound A, GW 338914X, Ph Eur Valaciclovir Impurity I, Ph Eur Aciclovir impurity A, Acetylacyclovir, 598U75, Acyclovir Related Compound A, Aciclovir Impurity A, Valaciclovir Hydrochloride Impurity I, Valaciclovir Impurity I.