5-Aryl-3-oxo-δ-lactones, with various substituents on the aromatic ring were prepared and tested for antifungal activity against Aspergillus flavus and Fusarium verticillioides, two common corn kernel rotting and mycotoxin producing fungi. Derivates containing chlorine and bromine displayed significant antifungal activity against A. flavus while 3-oxo-5-phenyl-δ-lactone was most active against F. verticillioides. Results of tests for antifungal activity using conventional paper disc assays, MIC and IC 50 values will be presented.