Abstract： Objective:30 compounds modified with diketopiperazine as parent core were screened for their antibacterial activities,and the compounds with ideal antibacterial effects against E.coli,Shewanella spp.,and P.aeruginosa were found.Methods:First,the absorbance of bacterial suspension and nutrient broth in the light oscillating incubator was measured by ultraviolet absorption spectrometry,and the growth curves of three putrefying strains were obtained.Secondly,the paper AGAR diffusion method was used to screen the antibacterial activity of the drugs,and the compounds with antibacterial effect were screened out from 30 compounds.Finally,the broth dilution method combined with ultraviolet spectrophotometer was used to determine the Minimum Inhibitory Concentration(MIC).Results:The MIC of 6-azauridine against the three putrefaction strains was 3.42 mg/mL,and the antibacterial effect increased with the increase of drug concentration.Conclusion:6-azauridine has a significant antibacterial effect on the three spoilage bacteria,which provides a certain data reference and theoretical support for the research and development of preservative preservatives in the later stage.