Synonyms: Atorvastatin Calcium Trihydrate Imp. D (EP), Atorvastatin Imp. D (EP), Atorvastatin USP Related Compound D, Atorvastatin USP RC D, 3-[(4-Fluorophenyl)carbonyl]-2-(2-methylpropanoyl)-N,3-diphenyloxirane-2-carboxamide, Atorvastatin Related Compound D, Atorvastatin Calcium Trihydrate Impurity D, Atorvastatin Impurity D