1. Centro C.N.R. Composti Eterociclici e loro Applicazioni and Dipartimento di Chimica Organica, via G. Capponi 9, 50121 Firenze, Italy
2. Alchem Laboratories Corporation, 13305 Rachael Boulevard, Alachua, Florida 32615
3. Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200 %katritzky@chem.ufl.edu