Isolation and structure of the cytostatic depsipeptide dolastatin 13 from the sea hare Dolabella auricularia

The Indian Ocean shell-less mollusc Dolabella auricularia superficially appears to lack predator defenses. Such seemingly defenseless animals are only attacked by certain carnivorous members of this gastropod subclass. Evidence is now accumulating that Opisthobranchia species have developed very powerful chemical defenses by careful selection and/or biosynthetic manipulation of various dietary sources such as blue-green algae and sponges.