1. Departamento de Química Orgánica; Facultade de Química, Universidade de Vigo; Vigo, 63 Spain310
2. Eenheid Algemene Chemie, Faculteit Wetenschappen; Vrije Universiteit Brussel; Pleinlaan 2 Brussels B-1050 Belgium
3. Faculty of Pharmacy, Department of Pharmaceutical Chemistry; National and Kapodistrian University of Athens; Panepistimioupolis-Zografou Athens 15771 Greece