ISOLATION AND STRUCTURE ELUCIDATION OF MIXTURES OF TWO NEW ISOPELLYNOLS FROM Halichondria sp.

This work is an update of our ongoing search for bioactive polyacetylenes from marine sponges which have been found to act as anti-proliferative and anti-cancers. Ether extract of the marine sponge Halichondria specie was obtained by partitioning the ethanol crude extract which was obtained by cold maceration of the wet sample material. The ether extract was subjected to open column chromatography to obtain fractions 1 to 8. Further fractionation of Fraction 5 using high performance liquid chromatography yielded 8 peaks from which peaks 3 and 4 were found to be mixtures of polyacetylenic alcohols upon elucidation of their structures based on data evidence from 1HNMR, 13CNMR, 2D-NMR and mass spectrometric analysis. These resulted in four compounds 1 to 4. Compounds 2 and 3 were identified to be a new C-31 compound named isopellynol J and 3 as a new C-32 compound named isopellynol B while compounds 1 and 4 were observed to be the known pellynol D and pellynol B respectively.