1. Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
2. Medical School, Faculty of Medicine, Health and Life Science, Swansea University, Swansea SA2 8PP, U.K.
3. School of Pharmacy and Pharmaceutical Sciences, Cardiff University, Cardiff CF10 3NB, U.K.
4. University of Chemistry and Technology, Prague, 166 28 Prague 6, Czech Republic
5. Department of Applied Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, U.K.
6. Department of Chemistry, University of Manchester, Manchester Institute of Biotechnology, 131 Princess Street, Manchester M1 7DN, U.K.