This compound, with CAS number 1422619-13-3, is known as Rosuvastatin Impurity Sodium Salt (5-Oxo Rosuvastatin Sodium Salt). It is a sodium salt form of a specified oxidative degradation product of Rosuvastatin, a widely prescribed statin medication. As a defined impurity, its primary and critical application is in the pharmaceutical quality control and analytical development processes for Rosuvastatin. It serves as a certified reference standard (CRS) or impurity standard for method validation, stability studies, and batch release testing to ensure the safety, efficacy, and purity of the active pharmaceutical ingredient (API) and its final dosage forms. Its identification and quantification are essential for regulatory compliance. This impurity standard is crucial for monitoring the degradation profile of Rosuvastatin during manufacturing and storage, helping to establish appropriate specifications and shelf-life for the cardiovascular drug product.