1. Department of Chemistry, National Tsing Hua University, 101 Section 2, Kuang-Fu Road, Hsinchu, Taiwan 300044, Republic of China
2. Department of Chemistry, National Chung Hsing University, Taichung ,Taiwan 402202, Republic of China
3. Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung ,Taiwan 80708, Republic of China