Synthesis And Nematicidal Biological Activity Of Cinnamic Acid Derivatives Containing 1,3,4-oxadiazole

Cinnamic acid is widely exists in cinnamon and benzoin,which is a kind of organic acid,belongs to the natural plant metabolites.Cinnamic acid and its derivatives have insecticidal,antibacterial,anti virus and other biological activities,It is found that the unsaturated double bonds in cinnamic acid can enhance the biological activity of the compounds.1,3,4-Oxadiazole is an important pesticide active group,it has a wide range of biological activities,such as insecticidal,antibacterial,antiviral,anti-inflammatory,and so on.However,there are few reports about its nematicidal activities.Based on this,a series of 1,3,4-oxadiazole thioether derivatives were designed and synthesized and evaluated the nematicidal activity of the compounds,cinnamic acid was used as the leading compound to modify its structure.The results of this paper are as follows:1.Cinnamic acid as the leading compound,we designed and synthesized a total of 26 novel cinnamic acid derivatives cotaining 1,3,4-oxadiazole group according to bioisoster principle,the structures of all the target compounds were elucidated by HRMS,elemental analysis,IR,1H NMR and 13 C NMR spectra.2.The title compounds were evaluated in vitro against Meloidogyne incognita and citrus nematode,avermectin and fosthiazate as control agents.The results of bioassay showed that most of compounds exhibited higher nematicidal activity against M.incognita and T.semipenetrans,especially compounds 4a,4b,4i showed high activity,while the concentration of reagent is 100 ?g/mL.3.The 3D-QSAR of compounds is studied with the method of CoMFA model and CoMSIA model based on their pLC₅₀ values,and the compound activity was predicted according to the CoMFA model and CoMSIA model,and a high activity compound 4z was synthesized.