1. Shaanxi Key Laboratory of Natural Products & Chemical Biology, College of Chemistry & Pharmacy, Northwest A&F University, Yangling 712100, People’s Republic of China
2. State Key Laboratory of Fluorine & Nitrogen Chemicals, Xi’an Modern Chemistry Research Institute, Xi’an 710065, People’s Republic of China
3. School of Pharmacy, Henan University, Kaifeng 475004, People’s Republic of China