अमूर्त

Identification, isolation, characterization and quantification of a new impurity in Rosuvastatin calciumtablet dosage form

Srinivasarao Koppala, Parsharamulu Rayam, V.Ranga Reddy, Jaya ShreeAnireddy

During the stability study of Rosuvastatin calcium (RSV) tablets, an unknown impurity was found at level of 0.8% by newly developed reverse phase HPLCmethod. The unknown impurity was identified by liquid chromatography –tandem mass spectrometry using electrospray ionization source and Q-trap mass analyzer (LC–ESI–QT/MS/MS). The drug product was subjected to stress to enhance the level of this impurity. The unknown was isolated by preparative liquid chromatography and characterized using the LC-MS, HRMS, NMR and IR spectral studies. Based on the spectroscopic data, the impurity was characterized as (3R,5S,E)-7-(4-(4- fluorophenyl)-6-isopropyl-2-(N-methylmethysulfonamido)pyrimidin-5- yl ) -3 ,5 -d ihyd r o xy-N-me thyl -N- ( (2S,3R,4R, 5R) -2 ,3 ,4 ,5 ,6 - pentahydroxyhexyl)hept-6-enamide (Imp-1). It is a novel impurity and not reported elsewhere. The newly developed method was validated as per ICH guidelines to demonstrate specificity, sensitivity, linearity, precision, accuracy and the stability-indicating nature.