1. Green Catalysis Center, and College of Chemistry Zhengzhou University 100 Science Avenue Zhengzhou 450001 Henan P. R. China
2. Chongqing Key Laboratory of Natural Product Synthesis and Drug Research Chemical Biology Research Center School of Pharmaceutical Sciences Chongqing University Chongqing 401331 P. R. China
3. School of Chemistry and Chemical Engineering Chongqing University Chongqing 401331 P. R. China