 degrees of unsaturation. The IR spectrum showed absorption bands for hydroxyl (0000 cm^−0^), conjugated carbonyl (0000 cm^−0^) and olefin (0000, 0000 cm^−0^) groups. The ^00^C NMR ([Supplementary Information, Figure S0](#marinedrugs-00-00000-s000){ref-type="supplementary-material"}), DEPTs and HSQC spectra 