A new bioactive sesquiterpenoid quinone from the Mediterranean Sea marine sponge Dysidea avara.

Investigation of the marine sponge Dysidea avara, family Dysideidae, afforded a new sesquiterpene (-)-N-methylmelemeleone-A (5), in addition to four known sesquiterpenes (+)-avarol (1), (+)-avarone (2), (-)-3'-methylaminoavarone (3) and (-)-4'-methylaminoavarone (4). The structure elucidation of compound 5 was based on 1D and 2D NMR spectroscopic, and HR-MS studies, as well as by comparison with the literature. Cytotoxicity, proteinkinase inhibition, inhibition of NFkB-activity and insecticidal activity were evaluated for the isolated compounds.