1. School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi’an, Shaanxi 710119, China
2. State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming 650201, China
3. Department of Chemistry, Kunming University, 2 Puxing Road, Kunming 650214, China