1. School
of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
2. Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
3. State
Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug
Discovery for Metabolic Diseases, Department of Pharmaceutics, College
of Pharmacy, China Pharmaceutical University, Nanjing 210009, China