Isolation and structure of glucosylceramides from the starfish Cosmasterias lurida.

From the water-insoluble lipid fraction of the methylene chloride/methanol extract of the starfish Cosmasterias lurida, two new glucosylceramides together with a known glucosylceramide, ophidiacerebroside E, were isolated by chromatographic procedures and characterized by spectroscopic (1H and 13C nuclear magnetic resonance, mass spectrometry) methods. The new compounds were identified as (2S,3R,4E,8E,10E)-1-(beta-D-glucopyranosyloxy)-3 -hydroxy-2-[(R)-2-hydroxyheptadecanoyl)amino]-9-methyl-4,8,10-o ctadecatriene (3) and (2S,3R,4E,8E,10E)-1-(beta-D-glucopyranosyloxy)-3 -hydroxy-2-[(R)-2-hydroxyoctadecanoyl)amino]-9-methyl-4,8,10-oc tadecatriene (4).