1. Institut für Organische Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, D-20146 Hamburg, Germany
2. Department of Entomology British Museum (Natural History), Cromwell Road, London SW7 5BD, United Kingdom
3. Pesticide Research Institute, Kyoto University, Kyoto, 606-01, Japan
4. Faculte des Sciences C. P. 160, Universite Libre de Bruxelles, Avenue F. D. Roosevelt 50, B-1050 Bruxelles, Belgium
5. Departement de biologie, Universite Laval, Quebec, P. Q., G1K 7P4, Canada