1. Department of Microbiology and Immunology, College of Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 11031, Taiwan
2. Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, 250 Wu-Shing Street, Taipei 11031, Taiwan
3. Department of Chemistry, Tamkang University, 151 Yingzhuan Road, Danshui District, New Taipei City 25137, Taiwan
4. Departments of Biochemistry and Chemistry, University of Washington, 4311 11th Avenue NE, Seattle, WA 98105-4068, USA
5. Department of Medicinal Chemistry, College of Pharmacy, Taipei Medical University, 250 Wu-Shing Street, Taipei 11031, Taiwan