1. Department of Organic and Applied ChemistryUniversity of Łódź, Tamka 12, 91–403 Łódź Poland
2. Institut für Chemie und Biochemie der Freien Universität Berlin, Takustr. 3 14195 Berlin Germany
3. Department of ChemistryUniversity of Zurich, Winterthurerstr. 190 CH-8057 Zurich Switzerland