Study On The Synthesis And Antibacterial Activity Of Phenylpropionamide Derivatives

Amide derivatives have a broad-spectrum biological activities,such as anti-microbial,inhibition of enzymes,and antitumor.Thiophene compounds have a widely applications,such as antibacterial,insecticidal,antiviral biological activities in the field of pesticides.Hydrazide compounds were a class of Schiff bases with subgroups?-CONHN=CH-?and had broad-spectrum applications in the fields of pesticides and medicine.Therefore,in this paper,thiophene ring and hydrazide structure were introduced into the amide by the principle of active splicing,and 34 new phenylpropanamide compounds containing thiophene hydrazide were designed and synthesized.The structure was characterized by ¹H NMR?¹³C NMR and HRMS.Compound V₃₃ was determined by single crystal diffraction.The main research contents are as follows:1.On the basis of Thifluzamide,3-aminothiophene-2-carboxylic acid methyl ester as a raw material,3-aminothiophene-2-carbohydrazide is obtained by hydrazylation reaction,and then condensed with different substituted aldehydes to obtaindifferentthiophenehydrazidecompounds.Finally,34novel phenylpropionamide compounds containing thiophene hydrazide structure were synthesized by amidation reaction.2.Target compounds were tested against Xoo,R.Solanacearum and Xac at the concentration of 100 and 50?g/mL by the turbidimeter tests.Bioassay results showed that compounds V₈,V₁₇,V₂₂ and V₃₄ had better inhibitory activity against Xoo,and the EC₅₀ values were7.1,8.8,9.5 and 4.7?g/mL,respectively,lower than thiodiazole copper?88.7?g/mL?and bismerthiazol?74.1?g/mL?.The EC₅₀ values of compounds V₁₂,V₁₄ and V₃₃ for against Rs were 7.6,7.6 and 7.9?g/mL,respectively,which were better than thiodiazole copper?66.8?g/mL?and bismerthiazol?72.3?g/mL?.Compounds V₁₂,V₁₄,V₃₃ and V₃₄ showed excellent antibacterial activity against Xac?Inhibition rate>80%?.3.The in vivo test of compound V₈ and V₃₄ against bacterial blight of rice were determined by the leaf-cutting method.The results indicated that the target compounds V₈ and V₃₄ showed better curative efficiencies on rice bacterial blight at the concentration of 200?g/mL,and their control effects were 51.4%and 52.1%,respectively,which was superior to commercial bactericides thiodiazole copper?49.5%?and bismerthiazol?47.8%?.4.Some compounds were assayed for their antibacterial activity against P.Infestans,G.zeae,and P.Sasakii by the mycelial growth rate method.Biological results indicated that the tested compound did not exhibit significant activity against the three phytopathogenic fungi at the concentration of 50?g/mL.