1. Center for Radiopharmaceutical Science of ETH, PSI and USZ, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland, Bayer Schering Pharma AG, Global Drug Discovery, D-13342 Berlin, Germany, Department of Chemistry and Biochemistry - Organic Chemistry, FU Berlin, Takustraβe 3, D-14195 Berlin, Germany