1. Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China
2. Department of Pharmaceutical Chemistry and Analysis, School of Pharmacy, Air Force Medical University, 169 Changle West Road, Xi'an 710032, China
3. School of Medicine, Xizang Minzu University, Key Laboratory for Molecular Genetic Mechanisms and Intervention Research on High Altitude Disease of Tibet Autonomous Region, Xianyang, Shaanxi 712082, China