1. School of Chemistry and Chemical Engineering, Chongqing University, 174 Shazheng Street, Chongqing 400044, P. R. China
2. Institute for Clean Energy and Advanced Materials, School of Materials and Energy, Southwest University, Chongqing 400715, P. R. China
3. Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, Innovative Drug Research Center, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P. R. China