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Isolation, identification, characterization, synthesis and quality control strategy of new process-related impurities
Wei-Dong Feng1, Song-Ming Zhuo2, Fu-Li Zhang3
1Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou 310014, China.
Abstract:
Ambrisentan is a highly selective endothelin-A receptor antagonist for the treatment of pulmonary arterial hypertension (PAH). The analysis of the process-related impurities will help not only to optimize the process parameters but also to develop reasonable analytical methods and set the quality standard for a quality control strategy in pharmaceutical manufacturing. During the manufacture of ambrisentan, five unknown impurities were detected in pilot batches ranging from 0.05% to 0.15% by HPLC. All of these impurities were isolated and synthesized successfully and were identified and characterized by LC-MS, HRMS, ESI-MS/MS(Q-Tof), 1D-NMR (1H, 13C, DEPT) and 2D-NMR (COSY, HSQC, HMBC) techniques. The formation mechanisms that yield these impurities are discussed for the first time. Quality control strategies to deal with these impurities are developed to obtain bulk drug of ICH-grade quality.
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