1. Department of Pharmacy, Pharmaceutical and Medicinal Chemistry; Saarland University; Campus C2 3 66123 Saarbrücken Germany
2. Department of Pharmaceutical Sciences, College of Pharmacy; University of Kentucky; 789 S. Limestone Street Lexington KY 40536 USA
3. Jiangsu Key Laboratory for Functional Substance of Chinese Medicine, School of Pharmacy; Nanjing University of Chinese Medicine; Nanjing 210023 P.R. China
4. Center for Pharmaceutical Research and Innovation, College of Pharmacy; University of Kentucky; 789 S. Limestone Street Lexington KY 40536 USA