1. Department of Phytochemistry, School of Pharmacy, Second Military Medical University, 325 Guohe Road, Shanghai 200433, P. R. China, Department of Traditional Chinese Medicine, Chinese Pharmaceutical University, Nanjing 210009, P. R. China, King Saud University, Riyadh 11451, Saudi Arabia, and School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, P. R. China