Synthesis and Insect Growth Regulatory Activity of Alkoxy-Substituted Benzaldoxime Ethers

Abstract

Alkoxy-substituted benzaldoxime ethers, namely (i) 3-methoxy-4-ethoxybenzaldoxime N-O-alkyl ethers, (ii) 3,4-dimethoxybenzaldoxime N-O-alkyl ethers, and (iii) 3,4-methylenedioxybenzaldoxime N-O-alkyl ethers, have been synthesized and evaluated for their insect growth regulatory activity against fifth-instar nymphs of the desert locust Schistocerca gregaria F. When injected into insect hemolymph at the lowest dose level of 3 µg/nymph, 3,4-methylenedioxybenzaldoxime N-O-methyl ether and 3,4-methylenedioxybenzaldoxime N-O-isopropyl ether showed 40 and 50% growth deformities respectively. On topical application (at 20 µg/nymph) 3-methoxy-4-ethoxybenzaldoxime N-O-methyl ether inflicted 100% abnormalties in insect growth. Structure-activity relationship studies revealed that maximum activity was associated with compounds having three carbons in the oxime ether moiety.

Synthesis, Reactivity and Biological Activity of Novel Bisbenzofuran-2-yl-Methanone Derivatives

“…On the other hand, limited biological activity studies on bis- benzofuran containing compounds were found [ 3 , 5 , 7 ]. As is known, oxime ethers have found many uses in recent years as nonsteroidal antinflammatory drugs [ 8 ], beta-adrenergic [ 9 ], mold inhibitory active compound in poultry science [ 10 ], anti-protozoan [ 11 ], insect growth regulator [ 12 ] and as various materials with steroidal effects [ 13 ].…”

Synthesis, Antifungal Activity and Structure-Activity Relationships of Vanillin Oxime-N-O-Alkanoates

“…Among the large number of oximine compounds, piperonal oxime N-O-alkyl ether exhibited insecticide synergistic activity far greater than that of piperonyl butoxide [9]. Several of these also exhibited anti-insect properties against Dysdercus kocnigii [10] and Schistocerca gregaria [11]. Chowdhury et al synthesized alkoxy-substituted benzaldoxime ethers and evaluated their IGR activity against the desert locust (S. gregaria) [11].…”

“…Several of these also exhibited anti-insect properties against Dysdercus kocnigii [10] and Schistocerca gregaria [11]. Chowdhury et al synthesized alkoxy-substituted benzaldoxime ethers and evaluated their IGR activity against the desert locust (S. gregaria) [11]. On topical application (at 20 µg/nymph), the most active 3-methoxy-4-ethoxybenzadoxime-N-methyl ether, caused 100% deformity.…”

“…The pattern of the proton peaks was almost the same in a homologous series, but differed from each other with respect to the number of peaks corresponding to the methylene or methyl protons constituting the alkanoyl moiety. The 1 H NMR spectrum of the representative vanillin oxime-N-O-heptanoate (11) showed two doublets at δ 6.93 and δ 7.45, and one double doublet at δ 7.04 corresponding to aromatic protons. Compound 2 has two hydroxyl functions and either of them could have been acylated.…”

Sequential Transformations of Phosphonates. One-Pot Synthesis of Ethoxycarbonyl Allyl Substituted Oxime Ethers

“…3 Oxime ethers also undergo many organic transformations in organic synthesis 4 and were used as intermediates in the synthesis of a variety of amino acids. 5 In addition, substituted oximes ethers have been found to have insect growth regulatory activity 6 and have application as insecticides, acaricides, and agrochemical fungicides. 7 In our continuing investigation of the sequential transformations of phosphonates in organic synthesis, [8][9][10] we report here, the sequential transformation of vinylphosphonate and its application to the synthesis of ethoxycarbonyl allyl substituted oxime ethers (Scheme).…”