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Published on: February 13, 2019
Synthesis and Insect Growth Regulatory Activity of Alkoxy-Substituted Benzaldoxime Ethers
1Divisions of Agricultural Chemicals and Entomology, Indian Agricultural Research Institute, New Delhi 110 012, India.
Journal of Agricultural and Food Chemistry
|February 7, 2001
Summary
New benzaldoxime ethers show promise as insect growth regulators. Certain compounds, particularly those with three carbons in the oxime ether moiety, caused significant growth deformities in desert locust nymphs.
Area of Science:
- Organic Chemistry
- Entomology
- Insect Physiology
Background:
- Insect growth regulators are crucial for pest management.
- Benzaldoxime ethers represent a class of compounds with potential biological activity.
- Understanding structure-activity relationships is key to developing effective agents.
Purpose of the Study:
- To synthesize novel alkoxy-substituted benzaldoxime ethers.
- To evaluate the insect growth regulatory (IGR) activity of these compounds.
- To establish structure-activity relationships for IGR efficacy.
Main Methods:
- Synthesis of three series of benzaldoxime ethers: 3-methoxy-4-ethoxy-, 3,4-dimethoxy-, and 3,4-methylenedioxybenzaldoxime N-O-alkyl ethers.
- Testing IGR activity against fifth-instar nymphs of the desert locust (Schistocerca gregaria F.) via injection and topical application.
- Analyzing dose-dependent effects and identifying specific active compounds.
Main Results:
- Compounds were synthesized and characterized.
- Intraperitoneal injection of 3,4-methylenedioxybenzaldoxime N-O-methyl ether and N-O-isopropyl ether at 3 µg/nymph resulted in 40% and 50% growth deformities, respectively.
- Topical application of 3-methoxy-4-ethoxybenzaldoxime N-O-methyl ether at 20 µg/nymph caused 100% growth abnormalities.
- Maximum insect growth regulatory activity was observed with compounds featuring a three-carbon oxime ether moiety.
Conclusions:
- Alkoxy-substituted benzaldoxime ethers exhibit significant insect growth regulatory activity against Schistocerca gregaria.
- The N-O-alkyl chain length, specifically three carbons, is critical for potent activity.
- These findings suggest potential for developing novel insecticides based on this chemical scaffold.
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