The sea hare Aplysia punctata from Sancti Petri (Cadiz, Spain) contain
s four new unusual acetates of linear polyhalogenated monoterpenes (5-
8) together with four known cyclic derivatives (1-4). The structures w
ere elucidated by interpretation of spectral data. It is suggested tha
t the new constituents of A. punctata might be biotransformation produ
cts. Compounds 6-8 showed significant in vitro cytotoxicity against fo
ur tumor cell lines.