1. School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, China
2. School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China
3. Qinghai Provincial Key Laboratory of Tibetan Medicine Research and Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Qinghai 810008, China