1. University of Göttingen, Institute of Organic and Biomolecular Chemistry, Göttingen, Germany
2. Chemistry of Natural Compounds Department, Pharmaceutical and Drug Industries Research Division, National Research Centre, Cairo, Egypt
3. Fachhochschule Ostfriesland, Emden, Germany
4. Institute for Biotechnology and Drug Research (IBWF), Kaiserslautern, Germany
5. Oncotest GmbH, Freiburg, Germany