Synthesis And Biological Activity Research Of N-nitro-2,4,6-trifluoroaniline And Sulfonamides Derivatives

Weeds have adverse effect on the production and quality of crops,and the increasing dosage of single variety of herbicides has caused the resistance of weeds surging severely.Therefore,the research of high-efficiency,low-toxic herbicides is extremely urgent.Fluorinated pesticide has the superiority of low dosage,high efficacy and fabulous biocompatibility,which attracts great interests of the scientists in the development of new pesticides.N-nitro-2,4,6-trifluoroaniline has been synthesized by our team,and has been initially demonstrated that it has plant growth regulating activity.In this paper,the effects of N-nitro-2,4,6-trifluoroaniline on rice seed germination,the growth of seedling and root system have been investigated.A series of N-nitrosulfonamides have been synthesized with N-nitro-2,4,6-trifluoroaniline taken as lead compound to acquire compounds with growth regulating activity.The specific research contents are as follows:1.Effects of N-nitro-2,4,6-trifluoroaniline on riceBased on the"TTC method"and"3,5-dinitrosalicylic acid method",the seed viability andα-amylase activity of rice seeds have been studied after soaking in different concentration of N-nitro-2,4,6-trifluoroaniline.The results have revealed that N-nitro-2,4,6-trifluoroaniline in a concentration of 2.5 mg/L has a promoting effect on the viability of rice seeds and the activity ofα-amylase in germination.The effects of different concentration of N-nitro-2,4,6-trifluoroaniline on seed germination,root length and stem length of rice were studied by the"plate method".The results have illustrated that N-nitro-2,4,6-trifluoroaniline in a concentration of 2.5mg/L has a promoting effect on the germination rate of rice seeds and the growth of rice seedling roots.The effects of different concentration of N-nitro-2,4,6-trifluoroaniline on the rice root morphology and root activity have been investigated by“hydroponic method”.The results have demonstrated that with the treatment of 2.5 mg/L N-nitro-2,4,6-trifluoroaniline,the total root length,root volume,surface area,number of root tips,root tip branch and root intersection of rice seedlings have increased dramatically.The optimal concentration of N-nitro-2,4,6-trifluoroaniline on rice should be 2.5 mg/L.2.Synthesis and activity test of N-nitrosulfonamides15 N-nitrosulfonamides have been synthesized by using N-nitro-2,4,6-trifluoroaniline as lead compound.The synthesis conditions have been optimized.2,4,6-trifluoroaniline was treated as the substrate,CHCl₃ as the solvent and pyridine as the acid binding agent,the intermediate was obtained after reacting 2.5 h,the target compound was synthesized by the nitric acid-acetic anhydride system,the yield was high.The structure of the target compound have been characterized by ¹HNMR,IR and HR MS.The growth regulation activities of 15 N-nitrosulfonamides on Sudan grass,barnyard grass,rice and wheat have been tested.Most of the N-nitrosulfonamides with a concentration higher than 25mg/L showed obvious growth inhibitory effect on Sudan grass and barnyard grass,and had a significant growth-promoting effect on rice.Compound A-8 exhibits severe inhibitory activity against Sudan grass and barnyard grass,and has an obvious growth promoting effect on rice and wheat at lower concentrations.The compound has showed certain selectivity to Sudan grass and barnyard grass,which has certain application prospect.