Study On Synthesis And Activity Of Novel Pesticide Compounds By The Method Of Cluster Effect And Substurcture Combination

Using two different approaches of pesticide discovery,4novel series of compounds were designedand synthesized, and their bioactivities were evaluated in this paper. The studies of mechanism of actionto the higher active compounds were done.1、 Based on the dual-site structure character of acetylcholinesterase （AChE）,40bivalentorganophosphorous compounds were designed and synthesized. Their structures were confirmed by1HNMR and elementary analysis. They were tested in vitro for inhibitory activity of AChE, their resultsshowed that compounds Opal6，Ophal7，Opnl9，Ophnl8had better AChE inhibitory activities, Thecompound Opnl9showed the excellent inhibitor activity to Drosophila melanogasteracetylcholinesterase （DmAChE） with the corresponding value of the IC50of23nM. Its activity was upto245to the positive control omethoate. The molecular docking study showed Opnl9contained favoritespacer bind to the catalytic centers and peripheral site Simultaneously,which highly improved the inhibitpotency of DmAChE.2、According to substurcture combination,32novel thiazole compounds were designed andsynthesized and systematically evaluated for their bioactivity. By pot-planting method, the bioassayresults showed compounds SZ-14and SZ-19had60%inhibition rate of fresh weight growth ofEchinochloa crusgalli L. and Portulaca oleracea L. at the dose of300g.a.i.ha^-1, the SZ-14was safe tocorn and rape. All the synthesized compounds displayed a wide range of fungicidal activity, of whichcompounds SZ-20displayed strong growth inhibition of Rhizoctonia solani with EC50of11.87g/mL,and SZ-22against Rhizoctonia solani Khn with EC50of17.06g/mL. Structure activity relationship（SAR） data of these compounds are as follows:1)4-H and5-methylene in the thiazole ring can help toincrease activity;2) compounds with electrondonating substituents on the2-position in the thiazole ringshowed higher herbicidal activity, while compounds with electron-withdrawing substituents performedfungicidal activity.3、 By the introduction of oxime ester structure to chlorantraniliprole pyrazole acid moiety based onthe substurcture combination, a series of62pyrazole acid oxime ester derivatives were synthesized andsystematically tested for their bioactivity. All the synthesized compounds displayed higher activitiesagainst Spodoptera exigua Hiibner than Plutella xylostella, among which PN58was the most activecompound against Spodoptera exigua Hiibner with LD50values of39.4g/mL. These compounds alsodisplayed well activity against aphids, and PN56is the best with LD50values of22.46g/mL. All thesynthesized compounds were excellent, PN8was the most active compound against Rhizoctonia solaniKhn with EC50values of10.70g/mL.