1. Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, P.R. China
2. Department of Pharmacy, Hunan University of Medicine, Huaihua, P.R. China
3. Beijing Kein Research Center for Natural Sciences, Beijing, P.R. China
4. Research Computing Center, University of North Carolina, Chapel Hill, NC, USA