1. Department of Pharmaceutical Chemistry, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
2. Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 8 St. Kliment Ohridski Boulevard, 1756 Sofia, Bulgaria
3. Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Boulevard, 1784 Sofia, Bulgaria
4. Institute of Optical Materials and Technologies, Bulgarian Academy of Sciences, Acad. G. Bonchev Avenue, Building 109, 1113 Sofia, Bulgaria
5. Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev Avenue, Building 9, Sofia 1113, Bulgaria