Polyhalogenated Monoterpenes from a Tasmanian Collection of the Red Seaweed Plocamium cartilagineum

Two new polyhalogenated monoterpenes (3E,7E)-8-bromo-(2E)- chloromethylene-(5R*,6R*)-dichloro-6-methyloctadien-1-al (1) and (1Z,3E,7E)-9-bromo-(1Z,5R*,6R*,9)-tetrachloro-6-methyloctatriene (2), together with two known compounds (3 and 4), were isolated and identified from the red alga Plocamium cartilagineum collected along the eastern coast of Tasmania. The structures were established by spectroscopic techniques.