1. Institute for Medical Research and Occupational Health, Ksaverska cesta 2, P.O. Box 291, 10001 Zagreb, Croatia
2. Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia
3. NMR laboratory, Institute of Chemistry, Faculty of Engineering, University of Pannonia, Egyetem utca 10, H-8201 Veszprém, Hungary