1. School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K., Institut de Chimie Moléculaire de Reims, CNRS UMR 7312, Université de Reims Champagne-Ardenne, Faculté de Pharmacie, 51 rue Cognacq-Jay, F-51096 Reims Cedex, France, and Department of Pharmacy, University of Bari “A. Moro”, Via E. Orabona, 4. I-70125 Bari, Italy