1. Department of Chemistry; Faculty of Medicine; University of Niš; Bulevar Dr Zorana Djindjica 81 18000 Niš Serbia
2. Department of Pharmacy; Faculty of Medicine; University of Niš; Bulevar Dr Zorana Djindjica 81 18000 Niš Serbia
3. Department of Pharmaceutical Chemistry; Faculty of Pharmacy; University of Ljubljana; Askerceva 7 1000 Slovenia
4. Institute of Biochemistry; Faculty of Medicine; University of Niš; Bulevar Dr Zorana Djindjica 81 18000 Niš Serbia