Characterization of an unknown impurity in doxofylline using LC-MS and NMR

Peixi Zhu1, Jingxian Lu2, Liya Hong2

  • 1College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, Zhejiang, China; KU Leuven, University of Leuven, Department of Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, Herestraat 49, O&N2, PB 923, 3000 Leuven, Belgium; Zhejiang Institute for Food and Drug Control, Hangzhou 310053, Zhejiang, China.

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