1. Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
2. Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
3. Department of Pharmaceutical Biosciences, Uppsala University, Box 591, SE-751 24 Uppsala, Sweden
4. Department of Chemistry, University of Gothenburg, SE-412 96 Gothenburg, Sweden
5. Swedish NMR Centre, University of Gothenburg, Box 465, SE-405 30 Gothenburg, Sweden