Curvulin and O-Methylcurvulinic acid: Phytotoxic metabolites of Drechslera indica which cause necroses on purslane and spiny amaranth

Curvulin was isolated from Drechslera indica and identified by X-ray crystallography. O-Methylcurvulinic acid was also isolated from this source and identified by NMR and HREIMS. Both compounds are phytotoxic to 2 of the normal hosts of this fungus when applied to detached leaves. Some plants are unaffected by these compounds. Host leaf constituents have some role in regulating the production of these phytotoxins by the fungus.