Atorvastatin acetonide methyl ester

(4R,6R)-6-[2-[2-(4-Fluorophenyl)-5-(1-methylethyl)-3-phenyl-4-[(phenyl amino) carbonyl]-1H-pyrrol-1-yl]ethyl]-2,2-dimethyl-1,3-dioxane-4-acetic acid methyl ester;