In order to deeply explore the effect of para-substituents on the antibacterial activity of N-benzyl-3-methylbuten-2- enamide derivatives, we elaborately synthesized three such para-substituted derivatives (compound a: N-(4-hydroxybenzyl)-3-methylbut-2- enamide
compound b: N-(4-isobutoxybenzyl)-3- methylbut-2-enamide
compound c: N-(4-isopropoxybenzyl) -3-methylbut-2- enamide), of which the structures were determined by ways of single crystal X-ray diffraction data analysis mainly. The antibacterial performance experiments showed that compounds a, b and c were evaluated for their antibacterial (Escherichia coli, Staphylococcus aureus, and Enterobacter aerogenes) activities. Among them, compounds a, b and c have an effective antibacterial reagents for E. coli exhibiting MIC values of 0.01, 0.01 and 0.01 g/mL, respectively, but inactive for E. aerogenes. In addition, compounds b and c have better activity than compound a against S. aureus with MIC values of 0.01 and 0.02 g/mL. These results provide an important basis for further study of the antibacterial properties and structure-activity relationship of these compounds, and are expected to provide valuable reference for the development of new antibacterial drugs.