1. Department of Organic Chemistry University of Chemistry and Technology, Prague Technická 5 166 28 Prague 6 Czech Republic
2. Central Laboratories University of Chemistry and Technology, Prague Technická 5 166 28 Prague 6 Czech Republic
3. Manchester Institute of Biotechnology and School of Chemistry The University of Manchester Manchester M1 7DN United Kingdom
4. Institute of Physical and Theoretical Chemistry University of Regensburg 93040 Regensburg Germany