1. Division of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, Republic of China
2. Department of Chemistry, Tunghai University, 181 Taichung Harbor Road Section 3, Taichung 407, Taiwan, ROC
3. National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan, ROC
4. College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan, ROC
5. Department of Chemical and Materials Engineering, Technology and Science Institute of Northern Taiwan, Taipei 112, Taiwan, ROC