DETERMINATION OF MINOR IMPURITIES OF 3-OYL]-1H,3H-PYRROLO[1,2-C]THIAZOL-3-YL)PYRIDINIUM CHLORIDE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY

Minor impurities of 3-oyl]-1H,3H-pyrrolo[1,2-c]thiazol-3-yl)pyridinium chloride (I), a pro-drug, were determined using highperformance liqui d chromatography. Manufacturing impurities, degradation products, and active drug, dimethylcarbamoyl)-6-(4-fluorophenyl)-indol-3-oyl] -1H,3H -pyrrolo[1,2-c]thiazole (II) were separated using a reversed-phase sys tem with gradient elution. Detector response was linear for II to appr oximately 470 mu g/mL which represents 47% of the drug concentration. The procedure provides relative standard deviations of 3.0% to 13.2% i n typical bulk drug lots. A variety of reversed-phased columns were ev aluated for the assay method with the optimum resolution achieved usin g a 5-mu m Zorbax Rx C-8 packing.