1. Department Pharmaceutical Microbiology at the Hans Knöll Institute Friedrich-Schiller-Universität Jena Beutenbergstrasse 11a 07745 Jena Germany
2. Department Biomolecular Chemistry Leibniz Institute for Natural Product Research and Infection Biology Hans Knöll Institute Beutenbergstrasse 11a 07745 Jena Germany
3. The Usona Institute 2800 Woods Hollow Road Madison WI 53711 USA