1. Chemistry Department, The American University in Cairo, AUC Avenue, New Cairo 11835, Egypt
2. Pharmacognosy Department, College of Pharmacy, Cairo University, Kasr El-Aini St., Cairo 11562, Egypt
3. Department of Chemistry, University of Ioannina, Ioannina 45110, Greece
4. Pharmacognosy Department, National Center for Natural Products Research, Giza 11111, Egypt