Atorvastatin 2-Fluoro t-Butyl Ester

Atorvastatin 2-Fluoro t-Butyl Ester is a structurally modified derivative of atorvastatin, featuring a fluoro-substituted t-butyl ester at the 2-position of the pyrrole ring. This substitution introduces a fluorine atom adjacent to the ester functionality, altering the compound's lipophilicity and metabolic stability compared to the parent drug. The molecule retains the core hydrogenated naphthalene and delta-lactone rings characteristic of atorvastatin. The fluoro-t-butyl ester moiety serves as a synthetic intermediate or degradation analog, specifically utilized as an HPLC reference standard for quantifying process-related impurities in atorvastatin active pharmaceutical ingredient (API) batches.