CRUCIGASTERINS, NEW POLYUNSATURATED AMINO-ALCOHOLS FROM THE MEDITERRANEAN TUNICATE PSEUDODISTOMA-CRUCIGASTER

Crucigasterins 277, 275, and 225, three new polyunsaturated amino alco hols, 10-12, were isolated from the Mediterranean tunicate Pseudodisto ma crucigaster. The structures of these compounds were assigned based on NMR and FABMS data. Absolute stereochemistry of the amino alcohol p ortion in 10 was assigned to be 2R,3S based on chiral GC comparison of 3-hydroxy-4-aminopentanoic acid 13d, a chemical degradation product o f 10, with a synthetic sample prepared from L-alanine. Compounds 10-12 exhibited moderate cytotoxicity and antimicrobial activity.