1. College of Chemistry and Pharmacy, Northwest A&F University, Yangling 712100, China
2. Key Laboratory of Botanical Pesticide R&D in Shaanxi Province, Yangling 712100, China
3. State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China