Activators based on structural modifications of l-methionine and methods of synthesis and use thereof

Abstract

The application belongs to the field of agricultural chemistry, and particularly relates to an activator based on structural modification of L-methionine and a synthesis method and application thereof; the application takes L-methionine as a core raw material, which is of natural origin, cheap and easy to obtain and excellent in biocompatibility, and performs structural modification through one-step esterification to synthesize a target compound 2-(diethylamino)ethyl-L-methionine ester; biological activity experiments prove that the compound can effectively promote the germination rate of crops at a low concentration, significantly optimize the growth state of roots and stems, and greatly enhance the stress resistance potential of seedlings; in addition, the compound has outstanding industrialization advantages, and is simple in production process, controllable in raw material cost and excellent in water solubility, with a solubility in water of greater than or equal to 30 g / L at 25 DEG C, so that it can be mass-produced without complex post-treatment, thereby not only effectively reducing the input cost of agricultural production, but also significantly improving the yield and quality of crops, and providing a new path for the development of green and environmentally-friendly plant growth activators.

Description

Technical Field

[0001] This invention relates to the field of agrochemical technology, specifically to activators based on L-methionine structure modification, their synthesis methods, and applications. Background Technology

[0002] As my country's economy and society enter a new stage of high-quality development, the construction of modern agriculture has shifted from "quantity assurance" to "equal emphasis on quality, efficiency, and green safety." This has placed more systematic and stringent standards on the cost controllability, technological intelligence, resource utilization efficiency, and environmental protection of the production process. Upgrading traditional agriculture to a new, efficient, and low-carbon agricultural model has become an inevitable trend. Currently, commercially available regulators (such as DA-6 and sodium nitrophenolate) are widely used, but they have the following shortcomings: some products have a simple structure (containing only a single active group), resulting in limited regulatory efficiency; some synthetic raw materials rely on imports, leading to high costs; and a few products have long residual periods in the soil, posing environmental risks.

[0003] L-Methionine, as a naturally occurring sulfur-containing essential amino acid, possesses unique advantages and is irreplaceable in terms of molecular structure, physiological function, and application potential. Its advantages include: 1. L-Methionine is widely found in plant proteins (such as soybeans and grains) and microbial fermentation products. It can be obtained through plant extraction and purification, or it can be produced on a large scale using mature microbial fermentation technology (such as synthesis using E. coli and yeast). The raw material cost is low.

[0004] 2. The amino (-NH2), carboxyl (-COOH), and sulfur-containing side chain (-CH2CH2SCH3) in its molecular structure endow it with good water solubility, and it can be prepared into an aqueous solution without the addition of a co-solvent.

[0005] 3. It exhibits good biocompatibility and can be degraded into harmless substances by microorganisms in soil, posing no risk of residue. Currently, there is limited research on ester derivatives with L-methionine as the lead structure in the field of plant growth regulation, and there are no reports on plant regulation-related derivatives and their biological activities. Developing such compounds has significant theoretical and applied value. Summary of the Invention

[0006] This invention uses L-methionine, a naturally sourced, low-cost, and biocompatible raw material, as a lead feedstock. Through a one-step, highly efficient esterification reaction, it condenses with N,N-diethylaminoethanol to synthesize the target compound 2-(diethylamino)ethyl-L-methionine ester. This method leverages the diethylaminoethoxy group to enhance growth-promoting targeting and utilizes the sulfur-containing side chain of L-methionine to improve stress resistance and synergistic effects, ultimately achieving the regulatory characteristic of "precise and efficient growth promotion at low concentrations," while avoiding the contradiction between efficiency and safety inherent in traditional products.

[0007] Another objective of this invention is to provide a simple method for synthesizing the above-mentioned compounds, as well as their application in crops such as wheat and soybeans, thereby providing technical support for the development of green agrochemical products.

[0008] To achieve the above-mentioned technical objectives, the technical solution of the present invention is as follows: The activator based on L-methionine structure modification has the following structural formula: ; The synthesis method of the activator based on L-methionine structure modification is as follows: ; The synthesis method is achieved through the following preparation steps: N,N-diethylethanolamine and L-methionine were mixed and dissolved in toluene. Then, the catalyst was added to the reaction system and heated to react. Water produced in the reaction system was separated by a water separator. After the reaction was completed, the heating was turned off and the reaction system was cooled to room temperature. The organic phase was filtered to remove insoluble matter, and the solvent was removed by vacuum distillation. The crude product was purified by silica gel column chromatography to obtain the target product 2-(diethylamino)ethyl-L-methionine ester.

[0009] The catalyst is titanium oxysulfate, and the molar ratio of N,N-diethylethanolamine, L-methionine and the catalyst is 1:(0.8-1.2):(0.04-0.06).

[0010] The heating reaction is carried out at a temperature of 110-130℃ for 5-7 hours.

[0011] The application of the activator based on L-methionine structure modification involves using it as an effective or activating ingredient to regulate plant growth activity.

[0012] The activator based on L-methionine structure modification is used as a growth activator for wheat and soybean.

[0013] When the activator based on L-methionine structure modification is used as an activator, the appropriate concentration for promoting the germination and growth of wheat and soybeans is 5-60 ppm.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. Based on the principle of superposition of active substances, and combining the structural characteristics of L-methionine and amino esters, the compound of this invention contains the active group diethylaminoethoxy of amino esters, and also combines the structural characteristics of L-methionine, which are structurally mutually supportive and have high atom utilization.

[0015] 2. 2-(diethylamino)ethyl-L-methionine ester has good water solubility, with a water solubility of ≥30 g / L at 25 °C.

[0016] 3. It has a good effect on the germination and growth of wheat and soybeans, and significantly improves the efficiency of plant regulation activity.

[0017] 4. The preparation method of this invention is simple, easy to scale up, uses inexpensive and readily available raw materials, and has low production and usage costs. Compared with existing activators, it requires less dosage, can significantly improve seed activity, promote rooting and germination, and enhance seedling resistance, providing a new option for activator development and showing great application prospects. Detailed Implementation

[0018] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0019] This embodiment provides a method for synthesizing an activator based on L-methionine structure modification, comprising the following steps: L-methionine (0.4 mol), N,N-diethylethanolamine (0.4 mol), toluene (100 mL), and the catalyst titanium oxysulfate (0.02 mol, 0.05 eq) are added to a 250 mL two-necked flask, and then heated to 120 °C for 6 h. Water produced in the reaction system is separated using a water separator. After the reaction is complete, heating is turned off, and the system is allowed to cool to room temperature. Insoluble matter is removed by filtration of the organic phase, and the solvent is removed by vacuum distillation. The crude product is purified by silica gel column chromatography (n-hexane / ethyl acetate = 1:1) to obtain the target product 2-(diethylamino)ethyl-L-methionine ester, with a yield of 94%.

[0020] 2-(Diethylamino)ethyl-L-methionine ester: 1 H NMR (400 MHz, D2O) d 4.46-4.31(m,2H), 4.22(t, J= 4.2 Hz, 1H), 3.42-3.35(m, 2H), 3.16-3.05(m, 4H), 2.55-2.45(m,2H), 2.22-1.98(m, 2H), 1.93 (s, 3H), 1.12 (t, J= 4.2 Hz, 6H). 13C NMR (400 MHz, D2O) 169.2, 60.5, 51.5, 49.8, 47.8, 28.4, 28.3, 13.8, 8.0. HRMS (ESI): [M+H] + calcd for 249.1558, found 249.1556. Example 2

[0021] This embodiment provides a method for synthesizing an activator based on L-methionine structure modification, comprising the following steps: L-methionine (0.32 mol), N,N-diethylethanolamine (0.4 mol), toluene (100 mL), and the catalyst titanium oxysulfate (0.016 mol, 0.04 eq) are added to a 250 mL two-necked flask, and the mixture is heated to 110 °C and reacted for 7 h. Water produced in the reaction system is separated using a water separator. After the reaction is complete, heating is turned off, and the system is allowed to cool to room temperature. Insoluble matter is removed by filtration of the organic phase, and the solvent is removed by vacuum distillation. The crude product is purified by silica gel column chromatography (n-hexane / ethyl acetate = 1:1) to obtain the target product 2-(diethylamino)ethyl-L-methionine ester, with a yield of 95%. Example 3

[0022] This embodiment provides a method for synthesizing an activator based on L-methionine structure modification, comprising the following steps: L-methionine (0.48 mol), N,N-diethylethanolamine (0.4 mol), toluene (100 mL), and the catalyst titanium oxysulfate (0.024 mol, 0.06 eq) are added to a 250 mL two-necked flask, and then heated to 130 °C for 5 h. Water produced in the reaction system is separated using a water separator. After the reaction is complete, heating is turned off, and the system is allowed to cool to room temperature. Insoluble matter is removed by filtration of the organic phase, and the solvent is removed by vacuum distillation. The crude product is purified by silica gel column chromatography (n-hexane / ethyl acetate = 1:1) to obtain the target product 2-(diethylamino)ethyl-L-methionine ester, with a yield of 94%.

[0023] Effect Examples Bioactivity Test

[0024] Preparation of 2-(diethylamino)ethyl-L-methionine ester activator: Weigh 0.5 g of activator and DA-6 respectively, add tap water to a final volume of 500 mL to obtain a 1 g / L activator stock solution, and then dilute to prepare activator solutions of 1 ppm, 5 ppm, 10 ppm, 20 ppm, 40 ppm, 60 ppm, and 80 ppm respectively. Tap water treatment was used as a control (CK).

[0025] b. Seedling cultivation: Wheat and soybean seeds of uniform size and plumpness were selected and placed in 25 mL beakers, with 30 seeds in each beaker. The prepared activator was poured into the beakers containing the seeds, and the seeds were soaked for 6 hours. After soaking, the seeds were evenly arranged on a moist paper bed for germination until the taproot showed white and the lateral roots just began to emerge. During this process, 1.0 g of agar was accurately weighed using an analytical balance and placed in a beaker containing 2000 mL of water. The water was heated in a microwave oven until completely dissolved, cooled, and then poured evenly into four 500 mL beakers until solidified, preparing the agar medium. The germinated seeds were then planted on the solidified agar and cultured in a 27 ℃ incubator. When the taproot of the control group (CK group) seeds touched the bottom of the beaker, all seedlings were removed and measured.

[0026] c. Measurement Indicators and Methods Seed germination rate: Number of germinated seeds / Total number of seeds Seedling sampling method: All seedlings were randomly sampled, with 10 seedlings randomly selected from each treatment as test samples, and the samples were repeated 3 times to detect the morphological and physiological indicators of the seedlings.

[0027] Plant height: The standard measurement is the length from the highest point of the leaf to the hypocotyl.

[0028] Root length: The measurement method is to select the three longest roots from a seedling and take their average value.

[0029] Dry weight of above-ground and underground parts: The measurement method is to wash the seedlings clean, absorb the surface moisture with filter paper, and divide them into above-ground and underground parts. They are blanched at 105 ℃ for 20 minutes, and then dried at 80 ℃ to constant weight. The dry weight is then measured.

[0030] The results of the bioactivity tests are shown in Tables 1 and 2.

[0031]

[0032]

[0033] Bioactivity experiments were conducted on wheat and soybean, respectively, and the results showed that: 1. Using the "seed soaking method" to test wheat germination and growth, it was found that this compound had a better effect on promoting wheat growth at 5-60 ppm, and its effect on promoting germination and growth was far superior to the blank control and DA-6 group; 2. Soybean germination and growth experiments were conducted using the "soaking method". It was found that the compound had a better effect on promoting soybean growth at 5-60 ppm, and its effect on promoting germination and growth was far superior to the blank control and DA-6 group.

[0034] The 2-(diethylamino)ethyl-L-methionine ester synthesized in this invention uses L-methionine and N,N-diethylethanolamine as raw materials. The process is simple and the cost is low. It has the advantages of "high efficiency regulation, good water solubility and no residue". It has shown better growth regulation effect than existing commercial regulators (DA-6) in crops such as wheat and soybeans. It provides a new direction for the development of green agrochemical products and has significant agricultural application value and market potential.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the preferred embodiments have been described in detail, those skilled in the art can still make appropriate modifications or equivalent substitutions to the solutions of the present invention, and such modifications or substitutions should be considered to still fall within the spirit and scope of the technical solutions of the present invention.

Claims

1. An activator based on L-methionine structural modification, characterized in that, Its structural formula is:

2. The method for synthesizing the activator based on L-methionine structure modification as described in claim 1, characterized in that, This is achieved through the following preparation steps: N,N-diethylethanolamine and L-methionine were mixed and dissolved in toluene. Then, the catalyst was added to the reaction system and heated to react. Water produced in the reaction system was separated by a water separator. After the reaction was completed, the heating was turned off and the reaction system was cooled to room temperature. The organic phase was filtered to remove insoluble matter, and the solvent was removed by vacuum distillation. The crude product was purified by silica gel column chromatography to obtain the target product 2-(diethylamino)ethyl-L-methionine ester.

3. The method for synthesizing the activator based on L-methionine structure modification according to claim 2, characterized in that: The catalyst is titanium oxysulfate, and the molar ratio of N,N-diethylethanolamine, L-methionine and the catalyst is 1:(0.8-1.2):(0.04-0.06).

4. The method for synthesizing the activator based on L-methionine structure modification according to claim 2, characterized in that: The heating reaction is carried out at a temperature of 110-130℃ for 5-7 hours.

5. The application of the activator based on L-methionine structure modification as described in claim 1, characterized in that... It can be used as an active ingredient or activator to regulate plant growth activity.

6. The application according to claim 5, characterized in that... It is used as a growth activator for wheat and soybeans.

7. The application according to claim 6, characterized in that... When used as an activator, the appropriate concentration for promoting the germination and growth of wheat and soybeans is 5-60 ppm.

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