1. Institute of Environmental and Occupational Toxicology, CH-6780 Airolo, Switzerland
2. Alpine Institute of Chemistry and Toxicology, CH-6718 Olivone, Switzerland
3. Walther-Straub-Institut für Pharmakologie
und Toxikologie, Ludwig-Maximilians-Universität München, D-80336 München, Germany
4. Masonic Cancer Center and Department of
Medicinal Chemistry, College of Pharmacy, University of Minnesota, 2231 Sixth Street SE, Minneapolis, Minnesota 55455, United States