1. Natural Products Chemistry Research Group, Organic Chemistry Division, Department of Chemistry, Faculty of Science and Technology, Universitas Airlangga, Surabaya, Indonesia.
2. Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Mulawarman, Samarinda, Indonesia.
3. Department of Management, Sekolah Tinggi Ilmu Ekonomi Muara Teweh, North Barito, Muara Teweh, Indonesia.