1. Institute of Marine Biochemistry, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Caugiay, Hanoi, Vietnam
2. Institute of Natural Products Chemistry, VAST, 18 Hoang Quoc Viet, Caugiay, Hanoi, Vietnam
3. College of Pharmacy, Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 406–840, Korea
4. College of Pharmacy, Gachon University, Incheon 406-799, Korea