1. Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, Netherlands.
2. Natural Products Laboratory, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE, Leiden, Netherlands.
3. College of Pharmacy, Kyung Hee University, 26, Kyungheedae-ro, Dongdaemun-gu, 02447 Seoul, Republic of Korea.