1. Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P. R. China
2. Analytical and Testing Center of Chongqing University, Chongqing University, Chongqing 401331, P. R. China
3. College of Pharmacy, Jinhua Polytechnic, Jinhua, Zhejiang 321007, P. R. China