Affiliation: | 1. Institut de Chimie des Substances Naturelles, CNRS, 91198 Gif‐sur‐Yvette Cedex (France), Fax: (+33)?1‐69077247;2. AstraZeneca R & D M?lndal, 431 83 M?lndal (Sweden);3. Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL‐SB‐ISIC‐LSPN, 1015 Lausanne (Switzerland), Fax: (+41)?21‐6939740 |