Study On The Synthesis And Biological Activity Of Novel Methoxy Acrylate Derivatives With Anti-plant Virus Activity

Strobilurins have the biological activity of antifungal,antibacterial,insecticidal,mite and weeding in pesticides.It is an important class of active compounds containingβ-methoxyacrylate.It has many advantages,such as high efficiency,low toxicity,wide spectrum,good absorbability,easy degradation and unique mechanism.Therefore,the research on its molecular design,synthesis and biological activity is still a hot spot in the creation of green pesticides.In our previous research,we found that dithioacetal and its derivatives had excellent antiviral activity,However,the inhibition effect on plant viruses still needs to be improved and the control effect of these compounds on Tobacco mosaic virus（TMV）is not satisfactory.In this paper,in order to create efficient,broad-spectrum and environmentally friendly small molecules of new antiviral drugs,dithioacetal unit with excellent bioactivity against plant virus was introduced.We proposed to introduce the dithioacetal group to increased-spectrum bioactive strobilurin to obtain 28 novel strobilurin derivatives bearing a dithioacetal moiety and further investigate the antiviral activities of strobilurin derivatives.The antiviral activities of these derivatives against PVY,CMV,and TMV were systematically evaluated.Moreover,the plant defense response mechanisms of C14,chlorophyll content,enzyme activities,and differential protein expression was researched.The conclusions and all works are outlined below:1.12 strobilurins intermediates containing substituents and 28 novel strobilurin derivatives bearing a dithioacetal moiety were designed and synthesized.The structure of all the intermediate compounds and target compounds were characterized by ¹H NMR,¹³C NMR,and HRMS.2.The antiviral activities of these derivatives against PVY,CMV,and TMV were systematically evaluated.Bioassay results showed that several title compounds showed more full-scale and better antiviral activity than commercially available Ningnanmycin,COS,and ribavirin,of which,compound C14 exhibited the best curative and protection activities against PVY,CMV and TMV in vivo,with 50%effective concentrations(EC₅₀)of 125.3,108.9,and 181.7μg/mL,respectively,and the latter had 148.4,113.2,and 214.6μg/mL,respectively,which were significantly superior to those of lead compound 6f（297.6,259.6,and 582.4μg/mL and 281.5,244.3,and 546.3μg/mL,respectively）,Ningnanmycin（440.5,549.1,and 373.8μg/mL and 425.3,513.3,and 242.7μg/mL,respectively）,Ribavirin（677.4,690.3,and686.5μg/mL and 652.7,665.4,and 653.4μg/mL,respectively）,and COS（553.4,582.8,and 513.8μg/mL and 547.3,570.6,and 507.9μg/mL,respectively）,.3.Moreover,defensive enzyme activities and RT-qPCR analysis demonstrated that the antiviral activity was associated with the SOD,CAT,and POD changes of tobacco.This finding was proved by the related proteins of abscisic acid signaling pathway.