Polyacetylenes from a Red Sea sponge Callyspongia species

From the methanolic extract of the Red Sea sponge Callyspongia sp. six new polyacetylenic compounds, aikupikanynes A-F, together with octahydrosiphono ehalyne, were isolated and identified. Their structures, which comprise fou r hydrocarbons, two alcohols, and one unprecedented alpha -hydroxy carboxyl ic acid, were determined by extensive 1D and 2D NMR studies and mass spectr al determinations.