1. Department of Pharmaceutical & Medicinal Chemistry, Institute of Pharmaceutical Sciences, Eberhard-Karls-University Tuebingen, Auf der Morgenstelle 8, 72076 Tuebingen, Germany
2. MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
3. Novartis Institutes for BioMedical Research, CH-4002 Basel, Switzerland