A benzylpyrimidine compound suitable for seed coating as an anti-amide herbicide and its application

Abstract

This invention discloses a benzylpyrimidine compound suitable for seed coating as an amide-resistant herbicide and its application. One benzylpyrimidine compound is 4,6-dichloro-5-benzyl-2-methylpyrimidine, C 11 H8Cl2N2, molecular weight 239.10. This invention relates to the application of the benzylpyrimidine compound in the preparation of seed coating agents resistant to amide herbicides. The invention focuses on how machine-sown and direct-seeded seeds in the middle and lower reaches of the Yangtze River resist herbicide damage in adverse field conditions. A novel amide-resistant herbicide compound, 4,6-dichloro-5-benzyl-2-methylpyrimidine, adapted for seed coating, is specifically designed through artificial synthesis. This compound is then nano-sized and ground to produce a seed coating agent. Finally, through coating, the seeds achieve significant resistance to herbicide damage, improving seed germination and seedling survival rates. The method is simple, easy to master, and highly operable.

Description

Technical Field

[0001] This invention belongs to the field of small molecule compounds and relates to a benzylpyrimidine compound suitable for seed coating as an anti-amide herbicide and its application. Background Technology

[0002] Rice and wheat double cropping is the main crop rotation pattern in the middle and lower reaches of the Yangtze River. Due to the production difficulties of tight crop rotation and short cycle in rice and wheat production, coupled with factors such as straw return to the field and labor shortage, various simplified rice and wheat cultivation methods such as mechanized sowing and direct seeding, which save labor and costs, have been widely accepted and applied. However, the resulting problems such as many weeds and severe weed damage have become pain points in agricultural production, seriously affecting the economic benefits of growers and food security. In production, the use of large amounts of amide-type herbicides, especially pretilachlor and butachlor, for weed control before seed germination and during the seedling stage is currently the most economical, effective and rapid way to solve weed problems. However, the following key problems still need to be solved in the large-scale application of herbicides: (1) Excessive use of herbicides inhibits the normal growth of crops. At present, although amide herbicides such as pretilachlor and butachlor have the advantages of broad weed control and outstanding effect, they are widely used in rice and wheat weed control. However, the efficacy of this type of herbicide is short-lasting and has high environmental residue. In order to achieve effective weed control, there are characteristics and disadvantages such as multiple applications and large dosages. Excessive herbicide can easily cause phytotoxicity and environmental pollution, and inhibit crop growth, especially seedling growth, resulting in yellowing and stunted seedlings, causing large-scale yield reduction. How to overcome herbicide phytotoxicity and achieve efficient weed control without affecting the normal growth of crops is a key problem that needs to be solved. (2) There is a lack of amide-resistant herbicide compounds that can be made into seed coating agents suitable for seed coating. Amide-resistant herbicide compounds are a special type of compound that selectively protects crops from herbicide phytotoxicity without affecting the activity of herbicides against target weeds. Polymerizing amide-resistant herbicide compounds into slow-release seed coating agents and achieving seedling protection and long-term weed control through slow release after sowing is currently a hot topic in the research and development of new high-efficiency seed coating agents. However, current amide-resistant herbicides are relatively limited in molecular configuration and resistance mechanisms, and some exhibit root growth inhibition after coating. Therefore, developing amide-resistant herbicides that do not inhibit root growth is crucial for the creation of novel slow-release coating agents. Addressing these issues, developing new, environmentally low-risk, and coating-suitable amide-resistant herbicides offers a novel and effective approach to solving the phytotoxicity and selectivity problems encountered in simplified weed control practices.

[0003] Seed coating agents are compositions containing one or more active ingredients that play an important role in seed disinfection, slow-release fertilizers and pesticides, pest and disease control, improving crop resistance, and reducing environmental pollution. Advanced formulations processed using high-tech nanotechnology allow the seed coating agent to adhere evenly and tightly to the seed surface, forming a protective film. The pesticide is concentrated around the seed, releasing slowly and is less affected by the external environment, making it difficult for surrounding pests to survive. It achieves excellent control and seedling protection without the need for other pesticides, resulting in high utilization efficiency and extended efficacy. The coated seeds have a smooth surface, which is beneficial for mechanical sowing. Furthermore, the coating agent can regulate the size of seeds from different seed sources, improving the efficiency and quality of mechanical sowing.

[0004] Upon review, there are currently no patents related to the synthesis of new compounds resistant to amide herbicides such as pretilachlor and butachlor, or their development into nano-type seed coating agents. In particular, there is a lack of corresponding technologies and methods for enhancing the herbicide resistance of seeds, promoting seed germination, and increasing seedling emergence rates in complex field environments such as machine-sown and direct-seeded rice. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned shortcomings of the prior art by providing a benzylpyrimidine compound.

[0006] Another object of the present invention is to provide the application of this benzylpyrimidine compound.

[0007] Another object of the present invention is to provide a rice seed coating agent.

[0008] The fourth objective of this invention is to provide the application of this rice seed coating agent.

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] A benzylpyrimidine compound, the structure of which is shown below:

[0011]

[0012] 4,6-Dichloro-5-benzyl-2-methylpyrimidine, C 11 H8Cl2N2, molecular weight 239.10.

[0013] The application of the benzylpyrimidine compound in the preparation of seed coating agents.

[0014] The application of the benzylpyrimidine compound in the preparation of seed coating agents for amide-resistant herbicides.

[0015] A rice seed coating agent is composed of the aforementioned benzylpyrimidine compound, a film-forming agent, a wetting agent, a dispersant, a thickener, and purified water. The film-forming agent is polyvinyl alcohol, the wetting agent is sodium dodecyl sulfate, the dispersant is sodium methylene dinaphthalene sulfonate, and the thickener is xanthan gum.

[0016] As a preferred embodiment of the present invention, the concentration of the benzylpyrimidine compound in the rice seed coating agent is 6-8 g / 100 ml, the concentration of the film-forming agent in the rice seed coating agent is 2-3 g / 100 ml, the concentration of the wetting agent in the rice seed coating agent is 1-1.5 g / 100 ml, the concentration of the dispersant in the rice seed coating agent is 1-3 g / 100 ml, and the concentration of the thickener in the rice seed coating agent is 0.5-1 g / 100 ml.

[0017] As a preferred embodiment of the present invention, the rice seed coating agent is formed by repeatedly grinding a mixture of the benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water to form a 6-8% concentration of benzylpyrimidine compound nanoscale stable suspension.

[0018] As a preferred embodiment of the present invention, the benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water are mixed and repeatedly circulated and ground to form a 6-8% concentration of benzylpyrimidine compound nano-type stable suspension, which is the rice seed coating agent.

[0019] As a preferred embodiment of the present invention, the benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water are mixed and then repeatedly circulated and ground for 100-120 minutes through a grinder, a chiller and a nano-sand mill. The indoor ambient temperature for all machines is maintained at 20-25°C, and finally a 6-8% concentration of benzylpyrimidine compound nano-type stable suspension is formed.

[0020] The application of the rice seed coating agent described in this invention in protecting crop seeds from amide herbicide damage.

[0021] A method for protecting crops from amide herbicides and enhancing the tolerance of protected crops to amide herbicides, comprising coating rice seeds with a germination rate of 90% or higher with the aforementioned rice seed coating agent, wherein the volume-to-mass ratio of the rice seed coating agent to the rice seeds is 1:30-50 (mL:g), and the coated seeds are then dried for later use.

[0022] As a preferred embodiment of the present invention, the volume-to-mass ratio of rice seed coating agent to rice seed is 1:30-40 (mL:g).

[0023] Beneficial effects:

[0024] This invention focuses on how machine-sown and direct-seeded seeds in the middle and lower reaches of the Yangtze River can resist herbicide damage in adverse field conditions. It utilizes a novel synthetic compound, 4,6-dichloro-5-benzyl-2-methylpyrimidine, specifically designed to resist amide herbicides and adapted for seed coating. This compound is then nano-sized and ground to create a seed coating agent. Finally, through coating, seeds achieve significant resistance to herbicide damage, improving germination and seedling survival rates. The method is simple, easy to master, and highly operable. This invention has the following advantages:

[0025] (1) Create compounds that are highly efficient, low-toxicity, and have broad-spectrum safe activity to resist amide herbicides.

[0026] (2) The developed safe and efficient herbicide-resistant compounds can be used in seed formulations to protect crops from herbicide damage, enhance the tolerance of protected crops to specific herbicides, thereby increasing crop safety and improving weed control.

[0027] (3) The benzylpyrimidine compound can be made into a nano-type rice seed coating agent. The lower dosage can solve the problem of low germination rate and low seedling emergence rate caused by herbicide damage in simple cultivation. It can improve the seed germination rate and seedling rate, reduce the amount of seeds used, and save costs.

[0028] (4) This nano-type rice seed coating agent is easy to use. It can be used immediately after coating or stored in advance without affecting the seed germination vigor and germination rate in the later stage.

[0029] (5) This benzylpyrimidine compound can be successfully synthesized in a high-efficiency and economical one-pot method with a high yield. Attached Figure Description

[0030] Figure 14. Electron micrograph of 6-dichloro-5-benzyl-2-methylpyrimidine

[0031] Figure 24, H spectrum of 6-dichloro-5-benzyl-2-methylpyrimidine

[0032] Figure 34, C-spectrum of 6-dichloro-5-benzyl-2-methylpyrimidine

[0033] Figure 4 Germination rate of different treatments

[0034] Figure 5 Germination rate control of different treatments

[0035] Figure 6 Plant height at 12 and 20 days after germination

[0036] Figure 7 Dry matter weight per seedling Detailed Implementation

[0037] Example 1: Synthesis of 4,6-dichloro-5-benzyl-2-methylpyrimidine

[0038] A sodium ethoxide solution was prepared using metallic sodium (3.04 g, 0.13 mol) and anhydrous ethanol (200 mL). Ethamidinium hydrochloride (6.619 g, 0.07 mol) and diethyl benzyl malonate (17.520 g, 0.07 mol) were added, and the mixture was refluxed at 90 °C for 4 h. After the reaction was completed and cooled to room temperature, the solvent was distilled off under reduced pressure. The crude sodium salt was dissolved in 1 L of distilled water, and concentrated hydrochloric acid (10 mL) was added to precipitate the intermediate. The precipitate was separated, washed with distilled water, and dried under vacuum at 80 °C for 6 h. Phosphorus oxychloride (80 mL) was then added, and the mixture was heated at 100 °C for 48 h. Excess phosphorus oxychloride was treated with 2 L of ice water, followed by extraction with dichloromethane (30 mL × 3). The organic phases were combined, dried over anhydrous MgSO4, filtered, and finally distilled under reduced pressure. The crude product was purified by column chromatography (V... 乙酸乙酯 :V 石油醚 =1:2), to obtain the final product 4,6-dichloro-5-benzyl-2-methylpyrimidine (9.707 g, 58%). 1 H NMR (400MHz, DMSO-d6) δ7.31(t,J=7.4Hz,2H),7.23(dd,J=13.9,6.5Hz,1H),7.17(d,J=7.4Hz,2H),4.21(s,2H),2.60(s,3H). 13 C NMR (100MHz, DMSO-d6) δ166.63(s), 161.48(s), 136.52(s), 128.83(s), 128.12(s), 127.93(s), 126.90(s), 34.74(s), 24.89(s).

[0039] Through nuclear magnetic resonance spectroscopy ( 1 H NMR, 13 The structure of 4,6-dichloro-5-benzyl-2-methylpyrimidine was verified by C10 NMR. Figure 2 The 1H NMR spectrum shows that the singlet signal peak at 2.60 ppm is attributed to the three hydrogens on the methyl group, the signal peak at 4.21 ppm to the two hydrogens on the benzylmethylene group, the signal peak at 7.16-7.18 ppm to the two ortho-position hydrogens on the benzene ring, the signal peak at 7.22-7.25 ppm to the para-position hydrogen on the benzene ring, and the signal peak at 7.29-7.33 ppm to the two meta-position hydrogens on the benzene ring. Figure 3The carbon spectrum shows that the compound contains characteristic peaks at 166.63, 161.48, 136.52, 128.83, 128.12, 127.93, 126.90, 34.74, and 24.89 ppm, indicating the presence of a benzene ring and a pyrimidine skeleton in the compound.

[0040] Example 2

[0041] (1) Preparation of seed coating solution

[0042] The 4,6-dichloro-5-benzyl-2-methylpyrimidine (6.00 g, hereinafter referred to as M15) prepared in Example 1 was mixed with the following additives: film-forming agent: polyvinyl alcohol (2.00 g, purity Mw9000-10000, 80% hydrolyzed, produced by Shanghai Maclean Biochemical Technology Co., Ltd.); wetting agent: sodium dodecyl sulfate (1.00-1.50 g, purity 92.5-100%, produced by Shanghai Maclean Biochemical Technology Co., Ltd.); dispersant: sodium methylene dinaphthalene sulfonate (1.50 g, purity 95%, produced by Shanghai Maclean Biochemical Technology Co., Ltd.); thickener: xanthan gum (0.72 g, USP grade, produced by Shanghai Maclean Biochemical Technology Co., Ltd.); and Wahaha brand purified water was added to 100 ml. The mixture was repeatedly circulated and ground for 150 minutes in sequence using an electric lifting basket mill (model: LZLM-3L, manufactured by Changzhou Lezu Machinery Technology Co., Ltd.), a chiller (model: ZP, manufactured by Changzhou Lezu Machinery Technology Co., Ltd.), and a nano-sand mill (model: LZNSM-0.3L, manufactured by Changzhou Lezu Machinery Technology Co., Ltd.). The ambient temperature during operation of all machines was maintained at 25℃. This resulted in a 6% concentration of fluoropyrimidine nanostructured stable suspension, which was used as the coating solution. A coating solution containing no 4,6-dichloro-5-benzyl-2-methylpyrimidine and with identical components was prepared using the same method as a control for subsequent experiments.

[0043] (2) Seed coating

[0044] In 2023, at the Wanfu Experimental Base of the Lixiahe Agricultural Research Institute in Yangzhou City, Jiangsu Province, 50 mu of rice was planted using a machine-sown rice variety with wheat straw returning to the field.

[0045] Select seeds with a germination rate of over 90%, and coat them evenly at a ratio of 1:30 (mL:g).

[0046] (3) Field sowing

[0047] After coating, the seeds are sown at the normal seed usage rate for field use, at 15 catties / mu.

[0048] (4) Field management

[0049] Post-sowing field management is the same as for normal fields. The herbicide used is pretilachlor, applied by machine or manual spraying simultaneously with seed sowing, at a rate of 350g / mu, which is 5 times the normal field application rate. The application rate and timing are the same for both indoor and field applications.

[0050] ① Improve seed germination rate

[0051] Five days after germination, the germination rate of this benzylpyrimidine compound (M15) as a seed coating agent was significantly higher than that of the control, both in the field and indoors. Figure 4 ).

[0052] ② Improve seedling survival rate

[0053] After a complete germination cycle, the survey showed that germination had basically stabilized after 12 and 20 days of seed germination, and the seedling survival rate in both the field and indoor pots was higher than that of the control. Figure 5 ).

[0054] ③ Increase plant height

[0055] like Figure 6 As shown in the figure, the investigation revealed that on the 12th and 20th day after seed germination, the plant height of plants treated with M15 as a seed dressing agent was significantly higher than that of the control, indicating that the seed dressing agent can promote plant height growth.

[0056] ④ Significantly reduced the incidence of yellowing and stunted seedlings

[0057] Herbicide damage to seeds and seedlings can easily lead to yellowing and stunted growth, resulting in large-scale yield reduction. As shown in Table 1, compared with the untreated control, treatment with M15 as a seed dressing agent reduced the incidence of yellowing seedlings by 81.54%, stunted growth by 93.58%, and the incidence of sheath blight in the later stage by 67.70%.

[0058] Table 1. Effects of M1 coating on seedling stunting and sheath blight damage.

[0059]

[0060] Data are averages, and different lowercase letters indicate significant differences in treatment at the 0.05 level.

[0061] ⑤ Promote the accumulation of dry matter weight in seeds and seedlings.

[0062] Depend on Figure 7 It can be seen that the dry matter content of the materials treated with M15 as a seed coating agent was significantly higher than that of the control, indicating that the substance has the function of promoting material transport.

[0063] ⑨ Significant increase in production

[0064] As shown in Table 2, the effective panicles per mu of rice treated with the above technical formula increased by 5.50% compared with the untreated control, the number of grains per panicle increased by 4.06%, the seed setting rate and thousand-grain weight were not significantly different, and the theoretical yield and actual yield increased by 9.12% and 10.99% respectively (see Table 2).

[0065] Table 2. Effects of M15 coating on rice yield.

[0066]

[0067] Data are averages, and different lowercase letters indicate significant differences in treatment at the 0.05 level.

Claims

1. The application of a benzylpyrimidine compound in the preparation of a seed coating agent, characterized in that, The benzylpyrimidine compound has the following structure: 。 2. The use of the benzylpyrimidine compound as described in claim 1 in the preparation of seed coating agents for amide-resistant herbicides.

3. A rice seed coating agent, characterized in that, It is composed of the benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water as described in claim 1, wherein the film-forming agent is polyvinyl alcohol, the wetting agent is sodium dodecyl sulfate, the dispersant is sodium methylene dinaphthalene sulfonate and the thickener is xanthan gum.

4. The rice seed coating agent according to claim 3, characterized in that, The concentration of the benzylpyrimidine compound in the rice seed coating agent is 6-8 g / 100 ml, the concentration of the film-forming agent in the rice seed coating agent is 2-3 g / 100 ml, the concentration of the wetting agent in the rice seed coating agent is 1-1.5 g / 100 ml, the concentration of the dispersant in the rice seed coating agent is 1-3 g / 100 ml, and the concentration of the thickener in the rice seed coating agent is 0.5-1 g / 100 ml.

5. The rice seed coating agent according to claim 4, characterized in that, The rice seed coating agent is made by repeatedly grinding a mixture of the benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water to form a 6-8% concentration of benzylpyrimidine compound nanoscale stable suspension.

6. The method for preparing the rice seed coating agent according to any one of claims 3-5, characterized in that, The benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water are mixed and repeatedly circulated and ground to form a 6-8% concentration of benzylpyrimidine compound nano-sized stable suspension, which is the rice seed coating agent.

7. The preparation method according to claim 6, characterized in that, The benzylpyrimidine compound, film-forming agent, wetting agent, dispersant, thickener and purified water are mixed and then repeatedly circulated and ground for 100-120 minutes through a grinder, a chiller and a nano-sand mill. The indoor ambient temperature for all machines is maintained at 20-25℃, and finally a 6-8% concentration of benzylpyrimidine compound nano-type stable suspension is formed.

8. The use of the rice seed coating agent according to any one of claims 3-5 in protecting crop seeds from amide herbicide damage.

9. A method for protecting crops from amide herbicides and enhancing the tolerance of protected crops to amide herbicides, characterized in that, Rice seeds with a germination rate of over 90% are coated using the rice seed coating agent according to any one of claims 3-5. The volume-to-mass ratio of the rice seed coating agent to the rice seeds is 1:30~50mL:g. After coating, the seeds are dried for later use.

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