1. Department
of Chemistry and Center of Excellence for Innovation in Chemistry,
Faculty of Science, Ramkhamhaeng University, Hua Mark, Bangkapi, Bangkok 10240, Thailand
2. College
of Oriental Medicine, Rangsit University, Muang Ake, Pathumthani 12000, Thailand
3. Chulabhorn Research Institute, Kamphang
Phet 6 Road, Bangkok 10210, Thailand
4. Natural
Products and Integrative Medicine Research Section, Research Division, National Cancer Institute, Rama VI Road, Bangkok 10400, Thailand