1. Organic Chemistry Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl.Ganesha 10, Bandung, West Java 40132, Indonesia
2. Pharmaceuticals Research and Development Laboratory of Farmaka Tropis, Faculty of Pharmacy, Mulawarman University, Jl.Penajam 01, Samarinda, East Kalimantan 75119, Indonesia