Affiliation: | Department of Inorganic and Analytical Chemistry, Attila József University, P.O. Box 440, H-6701 Szeged Hungary Hungarian Academy of Sciences, Biological Research Centre, Isotope Laboratory “B” Level, P.O. Box 521, H-6721 Szeged Hungary Eenheid Organische Chemie, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels Belgium |