New polychlorinated pyrrolidinones from the Red Sea marine sponge Lamellodysidea herbacea

Seven new polychlorinated derivatives have been isolated in addition to the known dysidamide, dysidamide B and dysidamide C from the Red Sea marine sponge Lamellodysidea herbacea. Their structures were established by extensive spectroscopic methods. Dysidamide exhibited neurotoxic effects towards both mesencephalic and cortical murine neurones at 0.8 μg/ml.