1. a Department of Organic Pharmaceutical Chemistry , Sciences II , University of Geneva , Geneva, CH-1211, Switzerland
2. b Research Department , Laboratoires Mayoly Spindler , 6, Avenue de l'Europe, Chatou Cedex, F-78401, France
3. c Rega Institute for Medical Research , Minderbroedersstraat 10, Leuven, B-3000, Belgium