Gebreyesus, Tarekegn (PhD)Yosief, Tesfamariam2018-06-252023-11-092018-06-252023-11-091988-06http://etd.aau.edu.et/handle/12345678/3361A new hexachlorinated metabolite, for which the 'name dysidimide is proposed, has been isolated from a Red Sea sponge of the genus Dysidea. Dysidimide was the major metabolite obtained from the ethanol extract o>f the dried sponge collected near Massawa, Repeated column chromatography on silica gel with pet-ether * chloroform and recryatallization yielded dysidimide as white needle crystals. The structure of dysidimide was determined by chemi- cal and spectroscopic studies including IR, MS, and ID and 2D NMR. The relative stereochemistry at C-4 and C-5 was deduced from nOe measurements on/ the 4-AcetateenRed Sea SpongeChemical Investigation of a Red Sea Sponge of the Genus DysideaThesis