Two novel sulfur derivatives, one of which is a glycoside, containing substituted 1,2,3-trithiocane cycles were isolated from Perophora viridis which was collected off the Atlantic coast of North Carolina. They were characterized by spectroscopic methods, mainly 1H NMR, 13C NMR, IR and UV spectroscopy and mass spectrometry. The compounds gave positive results in the brine shrimp toxicity assay and the sea urchin test.