1. Department of Chemical Biology and Drug Discovery Utrecht Institute for Pharmaceutical Sciences Utrecht University 3584 CG Utrecht The Netherlands
2. Department of Chemistry University of Natural Resources and Life Sciences Muthgasse 18 A-1190 Vienna Austria
3. Complex Carbohydrate Research Center University of Georgia Athens GA 30602 USA
4. Bijvoet Center for Biomolecular Research Utrecht University 3584 CH Utrecht The Netherlands
5. Chemistry Department University of Georgia Athens GA 30602 USA