1. Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 East Mabel Street, P.O. Box 210207, Tucson, Arizona 85721, United States
2. Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Chemical Engineering, East China Normal University, Shanghai, China, 200062
3. Natural Products Center, School of Natural Resources and the Environment, College of Agriculture and Life Sciences, University of Arizona, 250 East Valencia Road, Tucson, Arizona 85706, United States
4. Department of Chemistry and Biochemistry, The University of Notre Dame, 251 Nieuwland Science Hall, Notre Dame, Indiana 46556, United States
5. School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, China, 510006