1. School of Science and Technology, Chemistry Division, University of Camerino, via S. Agostino 1, 62032 Camerino,
Macerata, Italy
2. Department of Pharmaceutical and Pharmacological Sciences, University of Padova, via Marzolo 5,
35131 Padova, Italy
3. Department of Chemistry and Biochemistry, The University of Texas at Arlington, Box 19065, Arlington,
Texas 76019-0065, United States