Plant antimutagenic agents, 7. Structure and antimutagenic properties of cymobarbatol and 4-isocymobarbatol, new cymopols from green alga (Cymopolia barbata).

Two new compounds, cymobarbatol and 4-isocymobarbatol, were isolated from the marine alga Cymopolia barbata. The complete structures and absolute stereochemistries of these compounds were elucidated by a variety of spectroscopic techniques and X-ray crystallography. Both compounds were found to be nontoxic over a broad concentration range to Salmonella typhimurium strains T-98 and T-100. Both compounds exhibited strong inhibition of the mutagenicity of 2-aminoanthracene and ethyl methanesulfonate toward, respectively, the T-98 strain plus a metabolic activator and T-100.