1. Faculty
of Traditional Thai Medicine, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
2. Department
of Chemistry, Faculty of Science, Prince of Songkla University, Hat-Yai,
Songkhla 90112, Thailand
3. X-ray
Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang Malaysia
4. Department
of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical
Sciences, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand
5. Department of Chemistry and Earth, Ocean & Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z1, Canada