1. Qinghai Provincial Key Laboratory of Tibetan Medicine Research and CAS Key Laboratory of Tibetan Medicine Research, Northwest Institute of Plateau Biology, Xining 810008, Qinghai, P. R. China
2. School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, Shandong, P. R. China
3. School of Pharmacy, Southwest Medical University, Luzhou 646000, Sichuan, P. R. China