1. Medical Academy, Department of General Biology, Kilinskiego l, PL‐15‐230 Bialystok 8, Poland
2. Australian National University, The Faculty of Sciences, Department of Chemistry, GPO Box 4, Canberra ACT, 2601, Australia
3. Universität – GHS – Essen, Fachbereich 9, Botanik, Universitätsstraße 5, D‐W‐4300 Essen, Federal Republic of Germany
4. Roche Research Institute of Marine Pharmacology, 4–10 Inman Road, P.O. B. 255, Dee Why, N. S. W., 2099, Australia