1. Department of Pharmacognosy and Chemistry of Natural Products, School of Pharmacy, University of Athens, Panepistimiopolis, Zografou, 15771 Athens, Greece; Department of Pharmaceutical Sciences, University of Florence, Ugo Schiff 6, Polo Scientifico, Sesto Fiorentino, 50019 Florence, Italy; and Department of Chemistry and Industrial Chemistry, University of Pisa, Risorgimento 35, 56126 Pisa, Italy