N-(9-Acetyl-6-oxo-6,9-dihydro-1H-purin-2-yl)acetamide; N2,9-Diacetylguanine (EP) ; Acyclovir Diacetyl guanine (USP) ; Acyclovir N-Methylene Dimer; N-(9-Acetyl-6,9-dihydro-6-oxo-1H-purin-2-yl)acetamide; 2,9-Diacetylguanine; Acyclovir Diacetylguanine Impurity; Aciclovir Impurity L; Diacetyl guanine (USP)