Alan Katritzky*a, Khalid Widyana,b, Kapil Gyandaa a Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200, USA Fax: +1(352)3929199; e-Mail: katritzky@chem.ufl.edu; b Department of Chemistry, Tafila Technical University, Tafila 66110, Jordan