Design, Synthesis And Bactericidal Activity Of Cinnamic Acid Sulfone Derivatives

Cinnamic acid which is the metabolite of phenylalanine after deamination has become one of the important research directions in the field of pesticides because it has many advantages,such as simple structure,easy availability of raw materials,low toxicity and extensive biological activity.Cinnamic acid-sulfone derivatives are an important class of active substances and have great application prospects and research value in the creation of new high-efficiency pesticides.The sulfone derivatives containing 1,3,4-oxadiazole were found with good antibacterial activities by our group previously.Therefore,a series of new cinnamic acid sulfone derivatives were synthesized by splicing the cinnamic acid structural with sulfone derivatives containing 1,3,4-oxadiazole and their bactericidal activities were evaluated.The work results are summarized as follows:1.The substituted cinnamic acid was using as starting material,thirty-one novel cinnamate-sulfone derivatives were synthesized by hydrazinolysis,cyclization,thioetherification,and oxidation reaction,and their structures were characterrized by¹H NMR,¹³C NMR and HRMS.2.The bactericidal activities of cinnamic acid sulfone derivatives in vitro on the rice bacterial leaf blight and leaf streak were evaluated by turbidity method.The results showed that 31 cinnamic acid sulfone derivatives have superior bactericidal activities in vitro against Xanthomonas oryzae pv.oryzae?Xoo?and Xanthomonas oryzae pv.oryzicola?Xoc?than thiodiazole copper and bismerthiazol.Among them,the compounds 5r and 5t showed the best bactericidal activities against Xoo,with the50%effective concentration(EC₅₀)values of 0.58 and 0.34?g/mL,respectively.The bactericidal activities against Xoc,the EC₅₀ values of compounds 5r and 5t were 0.34and 0.20?g/mL,respectively.3.The antibacterial activities in vivo of 5t were further evaluated.Bioassay results demonstrated that the activities of target compound 5t in protective and curative of the rice bacterial leaf blight and leaf streak were superior to the control agents thiodiazole copper and bismerthiazol.4.The CoMFA and CoMSIA models were constructed based on the structure of the target compound and its biological activities against Xoo.The results provided a more valuable clue for the rational design of cinnamic acid sulfone derivatives.