Study On Screening And Activity Of A Novel Inhibitor Of Phenylhydrazono-2-one On Magnaporthe Grisea

Fungicides are one of the main types of pesticides.Fungicides protect crops from pathogens.However,due to the large-scale use of fungicides,The problem of drug resistance is becoming more and more serious.Finally,the failure of fungicides is eliminated.Perennial use of fungicides causes residues and pollute the environment,also pose a threat to human health.The development of spectrometers,high-efficiency,and low-toxic antimicrobial is currently the focus of research.As a common rice pathogenic fungus,rice blast fungus seriously jeopardizes the safety of food crops.At the same time,as a model organism,Magnaporthe grisea is one of the common target organisms in fungicidal design and activity testing.Phenylhydrazone compounds have a wide range of biologically activities.A large number of phenylhydrazone compounds were synthesized and the inhibitory activity against Magnaporthe grisea and Candida albicans were determined by our research group.The solubility of the compound limits the further study of the compound.In order to find high activity and good solubility compounds,we obtained phenylhydrazono-2-one compounds.After the determination of the phenylhydrazono-2-one compounds on the inhibitory activity of rice blast fungus is better than the phenylhydrazone compounds previously synthesized by the research group.This article has evaluated the biological activity of phenylhydrazono-2-one compounds,mainly in the following aspects:1.The inhibitory activities of 118 compounds against rice blast fungus were tested,and the importance of the structure skeleton of phenylhydrazono-2-one compound for the antibacterial activity of the compound was determined.The relationship between different substituents and inhibitory activity was examined.The EC50 value of 28 compounds against M.grisea was less than that of Triadimefon(6.4+0.30 ppm).The EC50 value of compound 512 against M.grisea was 1.22±0.06 ppm,and the EC50 value of compound 111 against M.grisea was 1.25±0.07 ppm,exhibiting a strong inhibitory effect on the growth of Magnaporthe grisea.2.19 kinds of plant pathogens were selected and the inhibitory effects of some compounds on the pathogens were determined.The compounds tested had a certain effect on 14 pathogenic bacteria.The EC50 value of compound 111 against Rhizoctonia solani was 0.44±0.10 ppm,and the EC50 value of compound 203 against summer patch was 0.21±0.04 ppm.The EC50 value for compound 104 against Alternaria solani was 0.09±0.02 ppm.It was demonstrated that phenylhydrazono-2-one compounds are expected to be developed into a class of spectrally efficient fungicides.3.The interaction between the compound and the M.grisea 3HNR and Leishmania CYP51 was tested and it was found that there was no interaction between the compound and the two target enzymes,indicating that the target enzyme was present in the phenylhydrazono-2-one compound.4.The inhibitory effect of the compound on cyanobacteria was examined and the acute toxicity of compound 111 against zebrafish was determined.Provides the basis for the further optimization and reformation of phenylhydrazono-2-one compounds.