Identification of a Degradation Impurity of Tipiracil Hydrochloride

Objective: To identify the alkaline degradation product of tipiracil hydrochloride and estab-lish an HPLC method for the determination of its related substances. Methods: The alkaline degradation product was analyzed by HPLC and its structural confirmation was unambiguously carried out by prepara-tion followed by characterization using Q-TOF/MS and NMR. The test for degradation and process impuri-ties of tipiracil hydrochloride is based on a Waters Atlantis T3 column (4.6 mm ×150 mm, 3μm); the mobile phase consisted of potassium dihydrogen phosphate and sodium heptane-sulphonate buffer solution (adjust to pH 3.0) - methanol with gradient elution; the detection wavelength was 210 nm. Results: Based on the spectral data, the alkaline degradation product of tipiracil hydrochloride was characterized as 4-(((5-chloro-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-yl)methyl)amino)butanamide. The main peak and every impurity peak were separated well. The LOD and LOQ of tipiracil hydrochloride and its impurities were 0.05μg· mL-1 and 0.15μg·mL-1, respectively. Conclusion: The investigation identified the impurity of tipiracil hy-drochloride produced under high pH conditions and the highly selective and reproducible HPLC offered an option in the quality control of tipiracil hydrochloride.