1. Departments of Nuclear Medicine, Pharmacotherapy, and Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands, Cygne B.V., Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, and Laboratory of Organic Chemistry, Eindhoven University of Technology, Eindhoven, The Netherlands