1. Department Chemistry and Biochemistry Clemens-Schöpf-Institute Technical University Darmstadt Alarich-Weiss Strasse 4 64287 Darmstadt Germany
2. Research Group Neurohomeostasis Department of Psychiatry and Psychotherapy University of Bonn Venusberg Campus 1 53127 Bonn Germany
3. Universität Potsdam Institut für Chemie Karl-Liebknecht-Strasse 24–25 14476 Potsdam Germany
4. Max-Planck-Institute of Biochemistry Am Klopferspitz 18 82152 Martinsried Germany