Isolation and structure of spongistatin 2, spongistatin 3, spongistatin 4 and spongistatin 6

Abstract

A black Spongia sp. in the Porifera class Demospongiae has been found to contain two new and exceptionally active cell (human cancer) growth inhibitors named spongistatin 2 and spongistatin 3. A bright colored Southwest Indian Ocean sponge Spirastrella spinispirulifera has also been found to contain related human cancer cell growth inhibitors named spongistatin 4 and spongistatin 6. A method of treating human cancer cells with spongistatin 1, spongistatin 2, spongistatin 3, spongistatin 4 and spongistatin 6 is also disclosed. The approximate mean GI.sub.50 of the disclosed compounds in the NCI cell line panel is about 10.sup.-10 .mu.g/ml.

Dependencies are inferred from the claim text.