Abstract: | Two new isoprenoid compounds, 6, 10-dimethylspiro 4,5] dec-6-ene-2, 8-dione and 2-(1′, 2′-dihydroxy-1′-methylethyl)-6, 10- dimethyl-9-hydroxyspiro 4,5] dec-6-en-8-one, have been isolated from potato tubers infected with Phoma exigua var. foveata. |