1. Departments
of Chemistry and Biology, University of Salerno, Via Giovanni
Paolo II 132, Fisciano 84084, Italy
2. Department
of Organic Chemistry, University of Barcelona, Martí i Franqués 1-11, Barcelona 08028, Spain
3. Department
of Chemistry, The Scripps Research Institute (TSRI), 10550 N. Torrey
Pines Road, La Jolla, California 92037, United States