1. Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, Bulgaria;
2. Department of Urology, University of Tübingen Hospital, Tübingen, Germany;
3. Department of Immunology, Institute for Cell Biology, University of Tübingen, Tübingen, Germany;
4. Interfacultary Institute of Biochemistry, University of Tübingen, Tübingen, Germany