Study On Synthesis And Bioactivity Of Spirotetramat Oxime Ether Derivatives And The Preliminary Exploration Of Screening Method Based On ACCase

The tetramic acid derivative spirotetramat (brand name Movento(?)), has shown an outstanding performance against sucking insect pests. The product acts as an inhibitor of lipid biosynthesis and shows no cross-resistance to any other insecticide. After foliar application spirotetramat penetrates through the leaf cuticle and is translocated as spirotetramat-enol via xylem and phloem, up to growing shoots and down to roots. This two-way systemicity (phloem and xylem transport) ensures the control of hidden and soil living sucking pests after foliar application and protects new shoots. Spirotetramat has been used against many species of whiteflies, aphids, mealy bugs, psyllids and selected thrips species in vegetables, cotton, soybean, pome and stone fruit, grapes, hop, citrus, nut trees and banana. The new mode of action renders spirotetramat as an excellent rotation partner with existing products for the management of aphid, whitefly and psyllid populations, which are frequently resistant to conventional insecticides. Moreover, only low adverse effects have been found on beneficial insects, such as Ladybugs, hoverflies and parasitic wasps, etc. which make the product suitable for modern integrated pest management (IPM) systems. These unique properties contribute to safeguarding the crop yield potential both in quality and quantity.In order to find compounds which have excellent insecticidal effect and accord with requirements of the development of efficient, broad-spectrum, safety pesticides, commercialized pesticide, on the basis of a literature review and combined with previous research of our research group, Spirotetramat was selected as lead compound and in its C-8position the oxime ether was introduced, and in the C-4position other bioactive substructures were also introduced at the same time. Two series of compounds I, II which contained a total of21novel compounds that have not been reported were synthesized. All of the compounds were characterized by1HNMR, MS, and elemental analysis. All of the target compounds were assayed for its bioactivity in the help of Hunan Bioassay Center Department. The inhibition activity against Aphis fabae showed:compounds of series I showed good insecticidal activity at test concentration of100mg/L and the inhibition rate reached above90%, close to Spirotetramat, such as compounds I-5,I-7,I-8,I-9,I-10,I-14,I-15. The inhibition activity against Tetranychus cinnabarinus showed:compounds of series I showed good insecticidal activity at test concentration of100mg/L and the inhibition rate of I-8,I-15reached above80%, higher than Spirotetramat (74.96%). The inhibition activity against Nilaparvata legen showed:most of the compounds of series I exhibited excellent bioactivity at test concentration of100mg/L and the inhibition rate of compounds I-5,I-8,I-9,I-14reached100%. Additional, the inhibition rate of compounds I-1,I-2,I-6,I-7,I-15were97.78%,95.96%,97.92%,93.33%,97.78%higher than Spirotetramat (89.67%), can be further optimized and screening. However, the activity of I-4is very poor, only5.46%.In order to be able to rapid screen compounds which have insecticidal effect, acetyl-CoA carboxylase (ACCase) was extracted from model organism Drosophila. And its activity was measured by ATP and ADP content in the HPLC before and after the reaction of ACCase with compounds. This method established a safe, simple and easy model to screing compounds in vitro.