SYNTHESIS AND INSECT GROWTH-REGULATORY ACTIVITY OF ALKOXY-SUBSTITUTEDBENZALDOXIME ETHERS

Alkoxy-substituted benzaldoxime ethers, namely (i) 3-methoxy-4-ethoxyb enzaldoxime N-O-alkyl ethers, (ii) 3,4-dimethoxybenzaldoxime N-O-alkyl ethers, and (iii) 3,4-methylenedioxybenzaldoxime N-O-alkyl ethers, ha ve been synthesized and evaluated for their insect growth regulatory a ctivity against fifth-instar nymphs of the desert locust Schistocerca gregaria F. When injected into insect hemolymph at the lowest dose lev el of 3 mu g/nymph, 3,4-methylenedioxybenzaldoxime N-O-methyl ether an d 3,4-methylenedioxybenzaldoxime N-O-isopropyl ether showed 40 and 50% growth deformities respectively. On topical application (at 20 mu g/n ymph) 3-methoxy-4-ethoxybenzaldoxime N-O-methyl ether inflicted 100% a bnormalities in insect growth. Structure-activity relationship studies revealed that maximum activity was associated with compounds having t hree carbons in the oxime ether moiety.