1. Dipartimento di Chimica, Università degli Studi “La Sapienza”, P.le A. Moro 5, 00185 Roma, Italy
2. Experimental Chemotherapy Laboratory, Regina Elena Cancer Institute, Via delle Messi d’Oro 156, 00158 Rome, Italy
3. Cancer Research UK Biomolecular Structure Group, The School of Pharmacy, University of London, London, U.K.