Isocoumarin Derivative as a Novel GABA Receptor Ligand from Neosartorya quadricincta

Abstract

For the purpose of discovering GABA receptor-directed insecticides in natural products, fungal culture extracts were screened for their ability to inhibit the specific binding of the noncompetitive antagonist [3H]EBOB to housefly head membranes. The screening efforts led to the isolation of a derivative of dihydroisocoumarin (PF1223) from the culture of Neosartorya quadricincta. This compound at 2.2 μM inhibited [3H]EBOB binding by 65%. This ligand might prove to be a lead compound for the identification of novel insecticides acting at the insect GABA receptor. © Pesticide Science Society of Japan