Marine Toxins of Latrunculia magnifica

Latrunculins A (1) and B (2) are the major extractable toxins of Latrunculia magnifica, constituting up to 0.35% of the dry weight of the sponge. The structure of the compounds was determined by detailed spectral analysis, some minor chemical transformations, and X-ray crystallography. The latrunculins are the first-known 2-thiazolidinone-bearing marine macrolides. They were found to cause major alterations in specific cytoskeletal proteins. A retrosynthesis of the new compounds is suggested.