Atorvastatin drug molecule, illustration. Molecular structure (top left) and molecular model (main image) of a molecule of the drug atorvastatin. This drug is sold under the brand name Lipitor. It is a statin drug, used to treat the high cholesterol levels that cause heart and vascular disease. It inhibits the HMG-CoA reductase, a key enzyme for the synthesis of cholesterol in the liver. The molecule's chemical formula is C33.H34.F.N2.O5. Atoms (tubular) are colour-coded: carbon (light blue), hydrogen (white), fluorine (green), nitrogen (dark blue), oxygen (dark red).