[1] Korea Res Inst Chem Technol, Med Chem Res Ctr, Taejon 305345, South Korea
[2] Hanyang Univ, Dept Chem, Seoul 133791, South Korea
[3] Chungnam Natl Univ, Grad Sch New Drug Discovery & Dev, Taejon 305764, South Korea
[4] Univ Sci & Technol, Dept Med & Pharmaceut Chem, Taejon 305350, South Korea