Sulfonylurea compound with high herbicidal activity and safety to crops as well as preparation method and application of sulfonylurea compound

Abstract

The invention relates to a series of sulfonylurea compounds with high herbicidal activity and safety to crops as well as a preparation method and application thereof. The sulfonylurea compounds with 5-site amido substituted benzene rings as shown in a general formula I are disclosed firstly; or a sodium salt derivative of the compound as shown in the general formula I, and the structure is as shown in a general formula II; the sulfonylurea compounds or derivatives shown in the general formula I or the general formula II can be used for preparing agricultural chemical herbicides and used for preventing and controlling weeds. When the sulfonylurea compound with the novel structure is used as a herbicide, a relatively good weeding inhibition rate can be ensured, and the safety of food crops can be ensured.

Description

Technical Field

[0001] This invention belongs to the field of agricultural chemical herbicides, and in particular relates to a sulfonylurea compound with high herbicidal activity and crop safety, its preparation method, and its application. Background Technology

[0002] In the 1970s, G. Levitt of DuPont in the United States first discovered sulfonylurea herbicides. In 1981, the first commercially available herbicide, chlorsulfuron, was introduced, ushering in an era of ultra-high efficiency in herbicide development. These herbicides are widely used due to their ultra-high efficiency, near-non-toxicity to mammals, broad spectrum, and high selectivity. Currently, dozens of commercially available varieties exist. These herbicides are highly effective against many annual or perennial weeds and are widely used to control weeds in rice paddies, soybean fields, corn fields, wheat fields, rapeseed fields, lawns, and other non-cultivated land.

[0003] However, with the widespread use of sulfonylurea herbicides, coupled with my country's large population and severe shortage of arable land, a unique cropping system of "multiple crop rotations per year" has emerged in my country. This has led to increasingly prominent problems, such as harmful residues. Chlorsulfuron-methyl, metsulfuron-methyl, and azoxystrobin, which are widely used internationally, degrade slowly in soil. Conventional use in wheat fields can leave long-term residues, causing varying degrees of phytotoxicity, even death, to subsequent crops such as corn, rapeseed, cotton, and some legumes, resulting in severe economic losses. Therefore, in 2013, my country banned the sale and use of three internationally widely used and well-known sulfonylurea herbicides—chlorsulfuron-methyl, metsulfuron-methyl, and azoxystrobin—and their mixtures, leading to a widespread ban on these herbicides domestically.

[0004] Li Zhengming et al. reported that introducing functional groups such as amino groups at the 5-position of the benzene ring of sulfonylureas such as chlorsulfuron greatly improved the degradation rate of the resulting compounds in soil, but most of the compounds had lower activity than chlorsulfuron and had a certain inhibitory effect on maize. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a herbicide with ultra-high herbicidal activity and safety for major food crops such as wheat and corn. The invention provides sulfonylurea compounds with high herbicidal activity and crop safety, along with their preparation methods and applications.

[0006] The technical solution adopted in this invention is: a sulfonylurea compound, the structure of which is shown in general formula I.

[0007] ;

[0008] Z is either C or N;

[0009] R1 It is one of the following: halogen, CO2CH3, CO2CH2CH3, CON(CH3)2, CON(CH3)2, CN, CF3, OCF3, OCHF2, SCF3, NO2, and C1-C6 alkyl groups;

[0010] R 2 and R 3 H, C1-C6 alkyl, C1-C6 alkyl containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkathioyl / arylthioyl / aryl / heterocyclic / silyl / alkenyl / alkynyl, C2-C6 alkenyl, C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / aryl / heterocyclic / silyl, C2-C6 alkyne, C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / arylthioyl One of the following: C2-C6 alkynyl, C1-C6 alkyl carbonyl, halogenated / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkathioyl / arylthioyl / aryl / heterocyclic / silyl / alkenyl / alkynyl carbonyl, aryl carbonyl, heterocyclic carbonyl, C1-C6 alkoxy carbonyl, aryloxy carbonyl, heterocyclic oxy carbonyl, C1-C6 alkylamine carbonyl, arylamine carbonyl, heterocyclic amine carbonyl, C1-C6 alkylthiocarbonyl, arylthiocarbonyl, and heterocyclic thiocarbonyl; R 2 With R 3 Same or different;

[0011] R 4 and R 5 It is one of H, Cl, CH3, CF3, OCH3, OCH2CH3, OCF3, OCH2CF3, OCHF2, SCH3, SCF3, NHCH3, and N(CH3)2; R 4 With R 5 Same or different.

[0012] Preferably, the halogen is chlorine; the alkyl group is methyl or ethyl; the alkenyl group is allyl with 3-6 carbon atoms; the alkynyl group is propargyl with 3-6 carbon atoms; R 4 and R 5 The components are H, CH3, and OCH3.

[0013] Preferably, Z is C or N; R 1 For Cl, R 2 and R 3 It is one of H, C1-C6 alkyl, allyl with 3-6 carbon atoms, propargyl with 3-6 carbon atoms, substituted C1-C6 alkoxycarbonylmethylene, and C1-C6 alkylcarbonyl; R 2 With R 3Same or different; R 4 and R 5 For H, CH3, OCH3; R 4 With R 5 Same or different.

[0014] Preferably, it is a sodium sulfonylurea salt compound with the structure shown in general formula II;

[0015] .

[0016] The preparation method of sulfonylurea compounds follows the synthetic route described below;

[0017]

[0018] Compounds of general formula I-1 and I-2 were dissolved in an organic solvent, and DBU was added to react at room temperature to prepare the compound shown in general formula I.

[0019] Preferably, the compound of general formula I is dissolved in water with sodium hydroxide, and the solution is removed under reduced pressure after stirring to obtain the compound of general formula II.

[0020] Preferably, the organic solvent is one or more selected from acetone, dichloromethane, chloroform, carbon tetrachloride, benzene, toluene, methanol, ethanol, ethyl acetate, tetrahydrofuran, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and dimethyl sulfoxide.

[0021] Application of sulfonylurea compounds in herbicides.

[0022] Preferably, it controls annual or perennial weeds.

[0023] A crop-safe herbicide comprising sulfonylurea compounds represented by formula I or formula II.

[0024] The advantages and positive effects of this invention are: it provides a series of new sulfonylurea compounds that, when used as herbicides, can ensure both a better herbicidal inhibition rate and the safety of major food crops such as wheat and corn. Detailed Implementation

[0025] The embodiments of the present invention will be described below.

[0026] This invention relates to a series of sulfonylurea compounds with high herbicidal activity and crop safety, their preparation methods and applications. First, it discloses sulfonylurea compounds with a 5-amino group substituted at the 5-position of the benzene ring, as shown in general formula I; or sodium salt derivatives of compounds shown in general formula I, with structures as shown in general formula II.

[0027]

[0028] in:

[0029] Z is selected from C or N;

[0030] R 1 Selected from halogens, CO2CH3, CO2CH2CH3, CON(CH3)2, CON(CH3)2, CN, CF3, OCF3, OCHF2, SCF3, NO2, and C1-C6 alkyl groups;

[0031] R 2 and R 3 Selected from H, C1-C6 alkyl, C1-C6 alkyl containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkathioyl / arylthioyl / aryl / heterocyclic / silyl / alkenyl / alkynyl, C2-C6 alkenyl, C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / aryl / heterocyclic / silyl, and C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / arylthioyl C2-C6 alkynyl, C1-C6 alkyl carbonyl, C1-C6 alkyl carbonyl containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkynthio / arylthio / aryl / heterocyclic / silyl / alkenyl / alkynyl, C1-C6 alkylcarbonyl, arylcarbonyl, heterocyclic carbonyl, C1-C6 alkoxycarbonyl, aryloxycarbonyl, heterocyclic oxycarbonyl, C1-C6 alkylamine carbonyl, arylamine carbonyl, heterocyclic amine carbonyl, C1-C6 alkylthiocarbonyl, arylthiocarbonyl, heterocyclic thiocarbonyl, etc.; R 2 With R 3 Same or different;

[0032] R 4 and R 5 Selected from H, Cl, CH3, CF3, OCH3, OCH2CH3, OCF3, OCH2CF3, OCHF2, SCH3, SCF3, NHCH3, N(CH3)2; R 4 With R 5 Same or different;

[0033] Furthermore, the halogen is fluorine, chlorine, bromine, or iodine; the alkyl group is a straight-chain or branched alkyl group; the alkenyl group is a straight-chain or branched group with 2-6 carbon atoms and may have a double bond at any position; the alkynyl group is a straight-chain or branched group with 2-6 carbon atoms and may have a triple bond at any position.

[0034] The synthetic routes for sulfonylurea compounds represented by general formula I are shown below;

[0035]

[0036] Following the above synthetic route, compound I-1 is synthesized from compound I-1a as the starting material, or from one of the intermediates I-1b, I-1c, I-1d, I-1e, I-1f, I-1g, and I-1h as the starting material; compound I-2 is synthesized by reacting compound I-2a with either I-2b or I-2c; compound I-1 and compound I-2 are dissolved in an organic solvent, a base is added, and the reaction is carried out at room temperature. After post-treatment and recrystallization, the target compound shown in general formula I is obtained.

[0037] The sulfonylurea compounds of general formula I form the sodium salts of sulfonylurea compounds of general formula II via the following pathway:

[0038]

[0039] The compound of general formula I is dissolved in water with sodium hydroxide and stirred at room temperature until the system turns pale yellow. The solution is then dissolved under reduced pressure to obtain the target compound of general formula II. The organic solvent is selected from acetone, dichloromethane, chloroform, carbon tetrachloride, benzene, toluene, methanol, ethanol, ethyl acetate, tetrahydrofuran, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, or dimethyl sulfoxide.

[0040] Sulfonylurea compounds or derivatives represented by general formula I or II can be used to prepare agricultural chemical herbicides. They can be used as active ingredients in pesticide compositions with agriculturally acceptable adjuvants for weed control; they can be used to control annual or perennial weeds and are safe for crops. When used as herbicides, these novel sulfonylurea compounds can ensure both excellent herbicidal inhibition rates and the safety of food crops.

[0041] The present invention will now be described. Experimental methods that do not specify the operation steps are performed in accordance with the corresponding product manuals. Unless otherwise specified, the instruments, reagents and consumables used in the embodiments can be purchased from commercial companies.

[0042] Example 1:

[0043] 1.1 Synthesis of 2-chloro-5-methoxyacetamido-benzenesulfonamide

[0044]

[0045] Synthesis of intermediate I-1b: Compound I-1a (34.77 mmol, 6.00 g) was placed in a 100 mL three-necked round-bottom flask, and then 50 mL of concentrated hydrochloric acid was added. The reaction system was placed in an ice-salt bath to lower the temperature to -5 °C and the reaction was continued for 30 min. The system gradually changed from a yellow turbid state to a white turbid state. Sodium nitrite (38.24 mmol, 2.64 g) was dissolved in 5 mL of water and slowly added dropwise to the reaction system. During the dropwise addition, the temperature change of the system was closely monitored and kept below -5 °C. A large number of bubbles were generated in the system, and the reaction system gradually turned into a yellow clear and transparent state, which is the diazonium salt solution. After the dropwise addition was completed, the reaction was continued at -5 °C for 30 min. Take another 1 L three-necked round-bottom flask, add CuCl2·2H2O (27.81 mmol, 4.74 g) and 50 mL concentrated hydrochloric acid, place the 1 L three-necked round-bottom flask in an ice-salt bath and cool it to below -5℃. Weigh NaHSO3 (173.84 mmol, 18.09 g) and put it into a 250 mL conical flask, add 150 mL of water to dissolve it. Slowly add the NaHSO3 solution and the prepared diazonium salt solution dropwise to the 1 L round-bottom flask at the same time. A large number of bubbles are generated and white solids precipitate. During the dropwise addition, the temperature of the reaction system should still be controlled below -5℃. After the dropwise addition is completed, continue to react in the ice-salt bath for 2 h, and then place it at room temperature for 3 h until no more bubbles are generated in the reaction system, a large number of white solids are generated in the system, and the solution turns blue. The solid was collected by vacuum filtration, dried under vacuum, and the filtrate was extracted once with ethyl acetate (200 mL). The filtrate was concentrated under reduced pressure and combined with the solid to give 7.2 g of the target compound I-1b, with a yield of 81%.

[0046] Synthesis of intermediate I-1c: Intermediate I-1b (28.12 mmol, 7.2 g) was dissolved in 100 mL of tetrahydrofuran, and the solution was yellowish-brown. The solution was cooled to 0°C in an ice bath, and 25% ammonia water (84.36 mmol, 13.00 mL) was slowly added dropwise. Initially, a large amount of solid precipitated in the system, but the solid dissolved as the addition continued. After the addition was complete, the reaction was continued in an ice bath for 1 h, and then placed at room temperature for 5 h. At this point, the reaction system was dark yellow. Upon standing, the lower layer was blue and the upper layer was yellow. After concentrating under reduced pressure to remove the solvent tetrahydrofuran, 100 mL of water was added to the system, and the pH of the system was adjusted to 3 with concentrated hydrochloric acid. A large amount of solid precipitated. After stirring for 30 min, the mixture was filtered, the filter cake was collected, and dried to obtain a yellowish-white solid I-1c, totaling 5.20 g, with a yield of 78.20%.

[0047] Synthesis of intermediate I-1d: Intermediate I-1c (7.69 mmol, 2.00 g) was dissolved in 50 mL of ethanol, and then 10 mL of water and reducing iron powder (23.06 mmol, 1.29 g) were added. Three drops of concentrated hydrochloric acid were added to initiate the reaction. After the reaction system stabilized, the mixture was heated to reflux and the reaction was monitored by TLC. After the reaction was completed, the reaction was stopped and cooled to room temperature. Diatomaceous earth was added and filtered. The filtrate was yellowish-brown. The ethanol was removed by concentration under reduced pressure, and a solid precipitated. 100 mL of water was added, and the mixture was stirred for 30 min and then filtered. The filter cake was collected, dried, and a pale yellow solid I-1d (6.52 mmol, 1.5 g) was obtained, with a yield of 84.75%.

[0048] Synthesis of intermediate I-1h: Compound I-1d (6.52 mmol, 1.5 g) was placed in 50 mL of dichloromethane, which appeared as a yellow turbidity. Then, DMF-DMA (N,N-dimethylformamide dimethyl acetal) (7.17 mol, 0.95 mL) was slowly added dropwise, and the system gradually turned into a clear yellow transparent state. After the addition was complete, the reaction was allowed to proceed at room temperature for 2 h. The reaction was monitored by TLC. After the reaction was completed, the mixture was concentrated under reduced pressure, and then 50 mL of water was added. A white solid precipitated out. After stirring for 1 h, the solid was collected by filtration and dried to obtain compound I-1h, totaling 1.71 g, with a yield of 92%.

[0049] Synthesis of intermediate I-1g: Compound I-1h (6.00 mmol, 1.71 g) was dissolved in 10 mL of tetrahydrofuran, and triethylamine (12.00 mmol, 1.66 g) was added. After stirring for 10 min, methoxyacetyl chloride (6.00 mmol, 0.65 g) was added. After the addition was complete, the reaction was carried out in a round-bottom flask at room temperature. The reaction was monitored by TLC. After the reaction was completed, the mixture was filtered, concentrated under reduced pressure, and separated by column chromatography to obtain a white solid I-1g, totaling 1.47 g, with a yield of 85%.

[0050] Synthesis of intermediate I-1: 3.19 mmol (1.0 g) of intermediate I-1 was placed in 10 mL of ethanol, and 9.57 mmol (0.67 g) of 80% hydrazine hydrate was added. The system gradually changed from a pale yellow turbid state to a clear, blood-red state. The reaction was monitored by TLC. After the reaction was complete, the mixture was concentrated under reduced pressure. Adding water resulted in the precipitation of a white solid. After stirring for 30 min, the mixture was filtered, and the solid was collected to obtain I-1 (2.81 mmol, 0.76 g), with a yield of 88%. If the amount of solid is small, the pH can be adjusted to 3-4 with concentrated hydrochloric acid, which will cause the solid to precipitate again.

[0051] Synthesis of intermediate I-2: I-2a (4-methyl-2-aminopyrimidine as an example) (9.16 mmol, 1.00 g) was placed in acetone, and anhydrous potassium carbonate (18.32 mmol, 2.53 g) and phenyl chloroformate I-2c (10.99 mmol, 1.72 g) were added. The reaction was stirred at room temperature and monitored by TLC. After the reaction was completed, the mixture was concentrated under reduced pressure to obtain a dark brown viscous substance. Water was added and stirred for 30 min, and a large amount of solid was dispersed. The mixture was filtered, the filter cake was collected, washed with water, and dried under reduced pressure to obtain 1.85 g of the target compound, with a yield of 88%.

[0052] Compounds I-2a (36.68 mmol, 5.0 g) and I-2b (107.03 mmol, 22.93 g) were placed in a 250 mL double-necked round-bottom flask. Ultra-dry tetrahydrofuran was added, and the system appeared as a gray turbidity. The reaction system was then placed in an ice bath, and after the temperature dropped below 0 °C, 60% NaH (44.06 mmol, 1.76 g) was slowly added in portions. After a short while, gas (H2) was generated. Once the gas stopped being generated, the reaction system was removed from the ice bath, and the reaction was continued at room temperature. The reaction was monitored by TLC. After the starting material I-2 was completely converted, the mixture was quickly filtered. The filter cake was washed with a small amount of dichloromethane, and the filter cake was collected to obtain a grayish-white solid, which was intermediate I-2, totaling 9.56 g, with a yield of 92.5%.

[0053] Synthesis of target compound I: Intermediates I-1 (1 equiv) and I-2 (1.1 equiv) were placed in a single-necked round-bottom flask, and acetonitrile was added. The reaction system was gray and turbid. Then, DBU (1.5 equiv) was slowly added dropwise. After the addition of DBU, the reaction system immediately became translucent. The reaction was stirred at room temperature and monitored by TLC. After the reaction was completed, the solution was concentrated under reduced pressure to obtain a pale yellow oil. The solution was dissolved in an appropriate amount of water, and the system became colorless, clear and transparent. If there were insoluble substances in the aqueous solution, diatomaceous earth could be used as a filter aid for filtration. The filtrate was collected, and 1 mol of hydrochloric acid solution was added dropwise under stirring at room temperature to adjust the pH of the system to 3-4. A large amount of white solid precipitated out. After stirring for 30 min, the solution was filtered, and the filter cake was washed with a small amount of water. The filter cake was collected, dried under vacuum, and separated by column chromatography to obtain a white solid, which was the target compound.

[0054] 1.2 Synthesis of 2-chloro-5-alkylamino-benzenesulfonamide

[0055]

[0056] Synthesis of intermediate I-1e: Compound I-1d (29.04 mmol, 6.00 g) was placed in 50 mL of dichloromethane, and the reaction system was then cooled in an ice bath. At 0 °C, trifluoroacetic anhydride (31.94 mmol, 4.5 mL) was slowly added. After the addition was complete, the system was milky white and turbid. The reaction was monitored by TLC. After the reaction was completed, the mixture was concentrated under reduced pressure, 100 mL of water was added, and the mixture was stirred for 1 h. The mixture was then filtered, the filter cake was collected, washed with a small amount of water, and dried to obtain compound I-1e, totaling 8.35 g, with a yield of 95%.

[0057] Synthesis of intermediate I-1f: Compound I-1e (6.52 mmol, 1.85 g) was placed in 50 mL of dichloromethane, and DMF-DMA (N,N-dimethylformamide dimethyl acetal) (7.17 mol, 0.95 mL) was slowly added dropwise. After the addition was complete, the reaction was carried out at room temperature for 2 h. The reaction was monitored by TLC. After the reaction was completed, the mixture was concentrated under reduced pressure, and then 50 mL of water was added. A white solid precipitated out. After stirring for 1 h, the solid was collected by filtration and dried to obtain compound I-1f, totaling 2.05 g, with a yield of 92%.

[0058] Dissolve 2-chloro-5-trifluoroacetamido-dimethylaminobenzenesulfonylimide in acetonitrile, and add the corresponding bromine-substituted product R. 3 Br and anhydrous potassium carbonate (1.2 equiv) were refluxed, and the reaction was monitored by TLC. After the reaction was complete, the mixture was filtered, the filtrate was collected, concentrated under reduced pressure, and purified by column chromatography. The resulting compound was dissolved in ethanol, and hydrazine hydrate (80%) was added. The system gradually changed from a pale yellow turbid state to a clear, blood-red state. The reaction was monitored by TLC. After the reaction was complete, the mixture was concentrated under reduced pressure, and water was added, resulting in the precipitation of a white solid. After stirring for 30 min, the mixture was filtered, and the solid was collected to obtain the corresponding sulfonamide intermediate. Different types of sulfonamide intermediates were prepared according to the different categories of bromine-substituted derivatives.

[0059] 1.3 Synthesis of 2-chloro-5-allylamino-phenylsulfonyl-3-(4-methoxy-6-methyl-1,3,5-triazin-2-yl)urea

[0060]

[0061] The 2-chloro-5-allylaminobenzenesulfonamide (1 equiv) prepared above and triazine (or pyrimidine)aminobenzoate (1.1 equiv) were placed in a single-necked round-bottom flask. Acetonitrile was added, and the reaction system was gray and turbid. Then, DBU (1.5 equiv) was slowly added dropwise. After the addition of DBU, the reaction system immediately became translucent. The reaction was stirred at room temperature and monitored by TLC. After the reaction was completed, the solution was concentrated under reduced pressure to obtain a pale yellow oil. A suitable amount of water was added to dissolve the solution, and the system became colorless, clear and transparent. If there were insoluble substances in the aqueous solution, diatomaceous earth could be used as a filter aid for filtration. The filtrate was collected, and 1 mol of hydrochloric acid solution was added dropwise under stirring at room temperature to adjust the pH of the system to 3-4. A large amount of white solid precipitated out. After stirring for 30 min, the solution was filtered, and the filter cake was washed with a small amount of water. The filter cake was collected, dried under vacuum, and separated by column chromatography to obtain a white solid, which was the target sulfonylurea compound.

[0062] Example 2:

[0063] Sulfonylurea derivatives were prepared using different raw materials according to the method in Example 1, and their structures are shown in any of the general formulas I, wherein R 1 -R 5 The functional groups are shown in Table 1, and compounds 1 through 656 were obtained, among which compound NO. 656 is chlorsulfuron (reference drug). Some derivatives... 1 ¹H NMR (Bruker AV400 spectrometer using tetramethylsilane as the internal standard), high-resolution mass spectrometry (HRMS), properties, melting point and yield are listed in Table 2.

[0064] Table 1. Structure of target compound I

[0065]

[0066] Table 2 shows the 1H NMR spectrum, 1C NMR spectrum, high-resolution mass spectrometry spectrum, properties, melting point, and yield of some target compound I.

[0067]

[0068] Example 3: Herbicidal Performance Testing of Sulfonylurea Compounds

[0069] Herbicidal activity of some target compound I prepared in Example 2 was tested on rapeseed, amaranth, barnyard grass, and crabgrass. The testing methods included foliar treatment and soil treatment. The testing methods are as follows:

[0070] 1) Preparation of the medicinal solution:

[0071] Preparation of emulsified water: First, prepare an emulsion with a concentration of 1‰. Weigh 1 g of emulsifier in a beaker, add a small amount of distilled water, dissolve it completely, and then pour it into a 1000 mL volumetric flask. Rinse the beaker several times with distilled water, pour the whole solution into the volumetric flask, and finally add distilled water to the mark. Shake well before use.

[0072] Preparation of stock solution: Weigh 10 mg of the test sample and dissolve it in 1 mL of DMF. After complete dissolution, prepare a stock solution of 10 mg / mL. Calculate the dosage according to the spray area, transfer the required volume to a 10 mL beaker, and add the corresponding volume of emulsified water to prepare an aqueous emulsion for spraying. If necessary, dilute stepwise to obtain the required aqueous emulsion for later use.

[0073] 2) Potted plant method (soil treatment)

[0074] A fixed amount of soil was placed in a 7.0 cm diameter plastic cup, along with a certain amount of water. Different dosages of the pesticide were applied to the soil using a spraying method. Afterward, sowing was carried out, and a fixed thickness of soil was added on top. The plants were then cultivated in a greenhouse, covered with plastic sheeting until seedlings emerged. A fixed amount of water was applied daily to maintain normal plant growth. Twenty-one days after treatment, the fresh weight of the above-ground parts was measured and compared with the untreated group to calculate the percentage of fresh weight inhibition. The test materials were: rapeseed (Brassicanapus), amaranth (Amaranthus retroflexus), barnyard grass (Echinochloacrus galli), and crabgrass (Digitaria adscendens).

[0075] 3) Potted plant method (stem and leaf treatment)

[0076] A fixed amount of soil was placed in a 7.0 cm diameter plastic cup, along with a certain amount of water. Sow the seeds, cover them with a layer of soil to maintain a certain thickness, and cultivate them in a greenhouse, covering them with plastic sheeting until seedlings emerge. Water the seedlings daily to maintain normal growth. After emergence, different dosages of pesticide were applied via foliar spraying. Twenty-one days after treatment, the fresh weight of the above-ground parts was measured and compared with the untreated group to calculate the percentage of fresh weight inhibition. The test materials were the same as in the pot method (soil treatment).

[0077] The herbicidal activity test results of sulfonylurea compounds are shown in Table 3.

[0078] Table 3. Herbicidal activity inhibition rate of some target compound I

[0079]

[0080] Example 4: Safety Performance Testing of Sulfonylurea Compounds

[0081] Some of the sulfonylurea compounds prepared in Example 2 were used as herbicides, and their safety against wheat, corn, rice, sorghum, millet, and soybeans was tested. The test procedure is as follows:

[0082] Using a pot experiment, soil and foliar treatments were applied to observe the safety of maize (Xindan 66), wheat (Yu 49-198), rice (57#-9), sorghum, millet (Gufeng No. 1), and soybean (Wansu 1208). Each treatment was repeated three times, and safety tests were conducted at doses of 2 and 4 g / mu.

[0083] Soil treatment: Add an appropriate amount of potting soil (loam:vermiculite:fertilizer soil = 1:1:1) to a 12 cm paper cup, spray the pesticide at a dose of 2.4 g / acre, sow the seeds after spraying, adjust the soil moisture, and cultivate in a greenhouse. Water the plants daily with a fixed amount of clean water to ensure normal crop growth. After a certain number of days, investigate the results and measure the fresh weight of the above-ground parts. The safety is expressed as the percentage of fresh weight inhibition.

[0084] Foliar treatment: Add an appropriate amount of potting soil (loam:vermiculite:fertilizer soil = 1:1:1) to a 12 cm paper cup, adjust soil moisture, sow seeds, and cultivate in a greenhouse. Before seedling emergence, cover with plastic film to ensure the temperature and humidity of the growing environment. Water daily with a measured amount of clean water to ensure normal crop growth. For corn (four-leaf to four-leaf-one-heart varieties), wheat (three-leaf to three-leaf-one-heart varieties), rice (three-leaf-one-heart to four-leaf varieties), sorghum (three-leaf-one-heart to four-leaf varieties), millet (four-leaf to four-leaf-one-heart varieties), and soybean (three-leaf to three-leaf-one-heart varieties), apply foliar spray at a dosage of 2-4 g / acre. After a specific number of days, investigate the results, measure the fresh weight of the aboveground parts, and express safety as the percentage of fresh weight inhibition.

[0085] Table 4 shows the safety test results of some target compounds I and II on crops maize (Xindan 66), wheat (Yu 49-198), rice (57#-9), sorghum, millet (Gufeng No. 1), and soybean (Wansu 1208).

[0086] Table 4. Safety test results of corn (Xindan 66), wheat (Yu 49-198), rice (57#-9), sorghum, millet (Gufeng No. 1), and soybean (Wansu 1208).

[0087]

[0088] As shown in Tables 3 and 4, the synthesized new sulfonylurea compounds, compared to the comparative chlorsulfuron (compound 656), not only demonstrate enhanced weed-control efficiency but also significantly improved safety for food crops. Based on these effects, this compound is particularly suitable for double-cropping wheat and corn, maintaining high weed control without affecting the growth of wheat and corn. These new sulfonylurea compounds can guide the development of novel sulfonylurea herbicides suitable for my country's unique farming practices and beneficial to ecological and environmental safety.

[0089] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A sulfonylurea compound, characterized in that: The structure is shown in general formula I. ； Z is either C or N; R 1 It is one of the following: halogen, CO2CH3, CO2CH2CH3, CON(CH3)2, CON(CH3)2, CN, CF3, OCF3, OCHF2, SCF3, NO2, and C1-C6 alkyl groups; R 2 and R 3 H, C1-C6 alkyl, C1-C6 alkyl containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkathioyl / arylthioyl / aryl / heterocyclic / silyl / alkenyl / alkynyl, C2-C6 alkenyl, C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / aryl / heterocyclic / silyl, C2-C6 alkyne, C2-C6 alkyne containing halogen / cyano / ester / amide / alkoxy / aryloxy / alkathioyl / arylamine / arylamine / alkathioyl / arylthioyl One of the following: C2-C6 alkynyl, C1-C6 alkyl carbonyl, halogenated / cyano / ester / amide / alkoxy / aryloxy / alkylamine / arylamine / alkathioyl / arylthioyl / aryl / heterocyclic / silyl / alkenyl / alkynyl carbonyl, aryl carbonyl, heterocyclic carbonyl, C1-C6 alkoxy carbonyl, aryloxy carbonyl, heterocyclic oxy carbonyl, C1-C6 alkylamine carbonyl, arylamine carbonyl, heterocyclic amine carbonyl, C1-C6 alkylthiocarbonyl, arylthiocarbonyl, and heterocyclic thiocarbonyl; R 2 With R 3 Same or different; R 4 and R 5 It is one of H, Cl, CH3, CF3, OCH3, OCH2CH3, OCF3, OCH2CF3, OCHF2, SCH3, SCF3, NHCH3, and N(CH3)2; R 4 With R 5 Same or different.

2. The sulfonylurea compound according to claim 1, characterized in that: Z is C or N; R 1 For Cl, R 2 and R 3 It is one of H, C1-C6 alkyl, allyl with 3-6 carbon atoms, propargyl with 3-6 carbon atoms, substituted C1-C6 alkoxycarbonylmethylene, and C1-C6 alkylcarbonyl; R 2 With R 3 Same or different; R 4 and R 5 For H, CH3, OCH3; R 4 With R 5 Same or different.

3. The sulfonylurea compound according to claim 1 or 2, characterized in that: These are sodium sulfonylurea salts with structures as shown in general formula II; 。 4. A method for preparing any one of the sulfonylurea compounds according to claims 1-3, characterized in that: According to the following synthetic route; 5. Compounds of general formula I-1 and I-2 were dissolved in an organic solvent, and DBU was added to react at room temperature to prepare the compound shown in general formula I.

6. The method for preparing sulfonylurea compounds according to claim 4, characterized in that: The compound of general formula I was dissolved in water with sodium hydroxide, and after stirring, the solution was removed under reduced pressure to obtain the compound of general formula II.

7. The method for preparing sulfonylurea compounds according to claim 5 or 6, characterized in that: The organic solvent is one or more of the following: acetone, dichloromethane, chloroform, carbon tetrachloride, benzene, toluene, methanol, ethanol, ethyl acetate, tetrahydrofuran, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and dimethyl sulfoxide.

8. The use of any of the sulfonylurea compounds according to claims 1-3 in herbicides.

9. The application according to claim 7, characterized in that: Control annual or perennial weeds.

10. A crop-safe herbicide, characterized in that: Includes the sulfonylurea compounds described in any one of claims 1-3.

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