1. Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2–4–41 Shinagawa-ku, Tokyo 142–8501, Japan
2. Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314–1 Shido, Sanuki City, Kagawa 769–2193, Japan
3. Department of Chemistry, Faculty of Science, University Malaya, 50603 Kuala Lumpur, Malaysia