1. Department of Chemistry, Faculty of Science; University of Kuwait: Safat; 13060, P.O. Box 5969, Kuwait
2. Pharmacognosy, Department of Medicinal Chemistry, Uppsala University, Biomedical Centre, Box 574, SE-751 23, Uppsala, Sweden, Sweden
3. Department of Chemistry, Faculty of Science, Cairo University, P.O. Box 12613 Giza, Egypt