1. Department of Medicinal Chemistry, Theodor Bilharz Research Institute (TBRI), Giza, Egypt
2. Department of Pharmacology, Theodor Bilharz Research Institute (TBRI), Giza, Egypt
3. ISAS – Institute for Analytical Sciences, Bunsen-Kirchhoff-Str. 11, D-44139 Dortmund, Germany. Fax: +49 – 2 31 – 1 39 21 20.