title: Application of ion-trap mass spectrometry for identification and structural determination of an unknown impurity in simvastatin.
abstract: Anhydro-simvastatin and simvastatin dimer are the two main impurities in the fermentation broth as well as in the final product of simvastatin, which is a hypolipidemic drug. An unknown impurity with m/z 451 for [(M + H)(+)] was detected in the analysis of final simvastatin drug sample. By using reverse phase high performance liquid chromatography (HPLC)-mass spectrometry (MS) and MS/MS spectra, the unknown impurity was detected and identified. Separation was achieved on ACE-5 C18 (150 x 4.6 mm, 3 microm column) at the flow rate of 1.2 ml min(-1) applying gradient elution of mobile phase A consisting of Milli-Q water of pH 3.0 with formic acid and B consisting of acetonitrile. MS/MS spectrum of the unknown impurity was obtained using HPLC-MS equipped with positive electrosoray ionization (ESI). The unknown impurity is named as 7-[7-(2,2-dimethyl-butyryloxy)-2,6-dimethyl-1,2,6,7,8,8a-hexahydro-naphthalen-1 -yl]-3-hydroxy-5-hydroxymethyl-heptanoic acid.
authors: Department of Chemistry, Sri Krishnadevaraya University, Anantapur, India.
authors: G V Ram
authors: GV
authors: Reddy
authors: A Praveen
authors: AP
authors: Kumar
authors: B Venkateswara
authors: BV
authors: Reddy
authors: J
authors: J
authors: Sreeramulu
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000032:analysis*; D013058:Mass Spectrometry; D019821:Simvastatin / Q000032:analysis*; D013607:Tablets
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D013607:Tablets; D019821:Simvastatin