1. WestCHEM Department of Pure and Applied Chemistry University of Strathclyde G1 1XL Glasgow UK
2. Current address: Fakultät für Chemie und Biochemie Ruhr-Universität Bochum Universitätsstrasse 150 44801 Bochum Germany
3. Innospec Ltd, Innospec Manufacturing Park Oil Sites Road CH65 4EY Ellesmere Port Cheshire UK