1. Laboratoire de Chimie des Substances Naturelles, MNHN, USM 0502/UMR 5154 CNRS, Case 54, 63 rue Buffon, F 75005 Paris, France, Swiss Institute of Bioinformatics, Molecular Modeling Group, Quartier Sorge, Batiment Genopode, CH-1015, Lausanne, Switzerland, Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, and Biomedical Research Centre, University of Dundee, Dundee DD1 9SY, U.K.