Geodin A Magnesium Salt: A Novel Nematocide from a Southern Australian Marine Sponge, Geodia

Abstract
A Geodia species collected from southern Australian waters of the Great Australian Bight has yielded a potent new in vitro nematocidal agent identified as geodin A Mg salt (1), a new macrocyclic polyketide lactam tetramic acid magnesium salt. The structure for 1 was assigned on the basis of detailed spectroscopic analysis.