1. Department
of Natural Drugs, Faculty of Pharmacy, University of Veterinary and Pharmaceutical Sciences Brno, CZ-612 42 Brno, Czech Republic
2. Department
of Drug Sciences, University of Padua, I-351 31 Padua, Italy
3. Mass
Spectrometry Group, Institute of Organic Chemistry and Biochemistry,
v.v.i., Academy of Sciences of the Czech Republic, CZ-166 10 Prague, Czech Republic