Simvastatin Ethyl Ester is an impurity of Simvastatin(S485000). Simvastatin is a synthetic derivative of a fermentation product of Aspergillus terreus. A competitive inhibitor of HMG-CoA reductase. A synthetic analog of Lovastatin. Antilipemic. Simvastatin, the drug, is sold under the trade name Zocor.