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Structure-activity Relationship for the Insect Antifeedant Activity of Benzofuran Derivatives
M Morimoto1, M Urakawa1, T Fujitaka1
1a Department of Agricultural Chemistry, Faculty of Agriculture, Kinki University.
Bioscience, Biotechnology, and Biochemistry
|July 8, 2016
Summary
Coumaran, a plant metabolite, deters insect feeding. Specific derivatives with methoxy and acetyl groups show enhanced antifeedant activity, particularly less lipophilic compounds.
Area of Science:
- Natural Products Chemistry
- Insect Chemical Ecology
- Plant Defense Mechanisms
Background:
- Coumaran (2,3-dihydrobenzofuran) is a secondary metabolite from Cyperus nipponicus, acting as a plant defense against herbivory.
- Benzofurans are a class of compounds investigated for their potential in pest management strategies.
Purpose of the Study:
- To evaluate the insect antifeedant activity of naturally occurring benzofurans.
- To determine the structure-activity relationships of benzofuran derivatives against insect feeding.
Main Methods:
- Bioassay using the common cutworm (Spodoptera litura F. Noctuidae) and the leaf disk method.
- Determination of antifeedant activity using the ED50 value calculated via probit analysis of dose-response curves.
Main Results:
- A specific 2,3-dihydrobenzofuran derivative, 7-acetyl-4,6-dimethoxy-2-isopropenyl-2,3-dihydrobenzofuran, exhibited potent antifeedant activity (ED50 = 1.3 μg/cm²).
- Methoxy and acetyl substitutions on the benzofuran structure significantly enhanced insect antifeedant properties.
- Antifeedant activity correlated inversely with the lipophilicity of the tested benzofuran compounds.
Conclusions:
- Substituted benzofurans, particularly those with methoxy and acetyl groups, are effective insect antifeedants.
- Lipophilicity is a key factor influencing the efficacy of benzofuran-based insect antifeedants.
- These findings support the development of natural product-derived compounds for sustainable insect pest control.
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