Isolation and identification of impurities after side reactions and degradation of febuxostat

Objective: To isolate and identify impurities after side reactions and degradation of febuxostat.Methods: LC- MS was adopted to analyze the structure of three impurities. The HPLC was performed on a Diamonsil C18( 200 mm ×4. 6 mm,5 μm) column with methanol-0. 1% acetic acid( 60∶ 40) as the mobile phase at a flow rate of 1. 0 m L·min- 1. Two impurities were separated from febuxostat by prep- HPLC,and their structures were further identified by IR...