1. Chemistry of Natural Compounds Department, National Research Centre, Cairo, Egypt;
2. Department of Pharmacognosy, Faculty of Pharmacy, October-6-University, 6th October City, Egypt;
3. Department of Chemistry, College of Science, Jazan University, Jazan, Saudi Arabia;
4. Chemistry of Tannins Department, National Research Centre, Cairo, Egypt;
5. Instituto de Productos Naturales y Agrobiología, La Laguna, Tenerife, Spain