1The Norwegian College Of Fishery Science, Marbio, Tromsø, NOR
2Department Of Chemistry, Smallstruct, Tromsø, NOR
3Norwegian College Of Fishery Science, Marbio, Tromsø, NOR
4 Norwegian College Of Fishery Science, Marbio, Tromsø, NOR
Fractions of the organic extract of the Arctic bryozoa Securiflustra securifrons were found to be cytotoxic against the human melanoma cell line A2058. Through dereplication by HR-MS analysis four compounds were nominated for isolation using mass-guided preparativ HPLC. This led to the purification of three novel halogenated indole-imidazole alkaloids, securamine H – J, together with one previously reported compound, securamine C. The structures of the new compounds were elucidated by spectroscopic methods including various 1D and 2D NMR experiments and analysis of HR-MS data.
Even though the structure of securamine C is known, its bioactivity has not been examined. The securamines were tested in a viability assay against three human cancer cell lines (human melanoma, colon carcinoma and breast carcinoma), as well as against non-malignant lung fibroblasts. All of the securamines affected cell viability in a dose-dependent manner. However, the cytotoxic potency of the compounds varied significantly.