Abstract: In order to elucidate structure-activity relationship of natural product Cedarmycins,a series of novel (4-methylene-5-oxo-tetrahydrofuran-3-yl) methyl benzoate derivatives (2a-2s) were synthesized by condensation of 4-(hydroxymethyl)-5-methylene-dihydrofuran-2(3H)-one with various substituted benzoate acids.The preliminary bioassay showed that some of these compounds have good fungicidal activity,especially against Rhizoctonia solani and Phytophthora capsici.The EC50 value of compound 2e (R=2,4-2Cl) were about 1.6 mg/L for the above fungus.