CN106565586B - Naphthalene sulfonamide compound, preparation method thereof and application thereof in regulating plant growth activity - Google Patents

Abstract

The invention discloses a naphthalene sulfonamide compound, a preparation method thereof and application thereof in regulating plant growth activity. The structure general formula of the naphthalenesulfonamide compound provided by the invention is shown in formula I. The naphthalenesulfonamide compound shown in the formula I has the advantages of simple structure, excellent plant growth regulation activity, simple and feasible preparation method and contribution to large-scale production.

Description

Naphthalene sulfonamide compound, preparation method thereof and application thereof in regulating plant growth activity

Technical Field

The invention belongs to the field of plant growth regulators, and particularly relates to a naphthalene sulfonamide compound, a preparation method thereof and application thereof in regulating plant growth activity.

Background

Abscisic acid is an important endogenous plant hormone, has a sesquiterpene structure, and plays an important role in plant physiological processes such as plant abscission layer formation, dormancy induction, germination inhibition, organ senescence and abscission promotion, stress resistance enhancement and the like, so that the reasonable utilization of abscisic acid has important significance in promoting the yield increase and income increase of crops, improving crop varieties and the like. However, due to the high production cost, rapid metabolic inactivation in plants and photo-isomeric inactivation of cis-double bonds at the 2-position of the side chain, abscisic acid cannot be popularized and applied in a large area in agricultural production. Therefore, abscisic acid functional analogs are one of the research hotspots in the art.

WO 2010093954A2 discloses an abscisic acid analogue Pyrabactin, which has the functions of inhibiting seed germination and regulating stomata closure, and subsequent researches show that the abscisic acid analogue Pyrabactin can also improve the drought tolerance of crops such as corn and the like and regulate the flowering time of citrus; WO 2013148339A1 discloses an abscisic acid analogue, Quinabactin, which can induce stomata to close and improve the drought resistance of soybeans and tomatoes; CN 102391147A discloses a class of aryl formamide cyclopropane abscisic acid analogues, and part of the compounds have plant growth regulating activity for inhibiting seed germination; CN103435472A discloses a high-activity benzisoabscisic acid analogue, the inhibitory activity of the compound to the germination of arabidopsis seeds is about 14 times of (+) -ABA; CN102911041A discloses a cyclopropanated abscisic acid analog at the 2, 3-position that is approximately 4 times as photostable as abscisic acid; WO 2015113944A1 discloses that the phosphate Pyrabactin analogue has abscisic acid-like functions, and part of compounds have the functions of regulating stomata closing and inhibiting seed germination.

Therefore, the abscisic acid analogue with low development cost, higher activity and better stability has very important significance for accelerating the application of the plant growth regulator in agricultural production, improving the quality and yield of agricultural products, maintaining environmental safety and the like.

Disclosure of Invention

The invention aims to provide a naphthalene sulfonamide compound, a preparation method thereof and application thereof in regulating plant growth activity.

The structure general formula of the naphthalenesulfonamide compounds provided by the invention is shown in formula I,

in the formula I, X is a halogen atom;

r is amino acid residue or amino acid ester residue;

wherein the amino acid residue is a group obtained by substituting amino hydrogen at a position alpha to carboxyl in amino acid;

the amino acid ester residue is a group obtained by esterification reaction of carboxyl in the amino acid residue and alcohol;

and the compounds of formula I do not include the following:

in the formula I, X is F, Cl, Br or I;

the amino acid residue is a group obtained by substituting amino hydrogen at the alpha position of carboxyl in any one of the following amino acids: alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), proline (Pro), phenylalanine (Phe), tryptophan (Trp), methionine (Met), glycine (Gly), serine (Ser), threonine (Thr), cysteine (Cys), tyrosine (Tyr), asparagine (Asn), glutamine (Gln), lysine (Lys), histidine (His), aspartic acid (Asp), glutamic acid (Glu) or the residue of 1-aminocyclopropanecarboxylic acid.

The amino acid ester residue can be specifically a group obtained by esterification reaction of carboxyl in the following amino acid residues and alcohol:

alanine (Ala), valine (Val), leucine (Leu), isoleucine (Ile), proline (Pro), phenylalanine (Phe), tryptophan (Trp), methionine (Met), glycine (Gly), serine (Ser), threonine (Thr), cysteine (Cys), tyrosine (Tyr), asparagine (Asn), glutamine (gin), lysine (Lys), histidine (His), aspartic acid (Asp), glutamic acid (Glu), or the residue of 1-aminocyclopropane carboxylic acid; more particularly serine methyl esters;

the alcohol is a monohydric alkyl alcohol or a dihydric alkyl alcohol; in the alcohol, the number of carbon atoms may be specifically 1 to 4.

The alcohol may more specifically be methanol, ethanol, n-propanol, isopropanol or tert-butanol.

Specifically, the compound shown in the formula I is any one of the following compounds:

the above-mentionedIn, R₁Is composed of

The above-mentionedIn particular to

The above-mentionedIn, R₂is-COOCH₃or-COOH;

the above-mentionedIn particular to

The above-mentionedIn, R₃Is composed of

The above-mentionedIn particular to

The above-mentionedIn, R₄is-OCH₃or-OH;

the above-mentionedIn particular to

The invention provides a method for preparing a compound shown as a formula I, wherein R is an amino acid ester residue, which comprises the following steps:

carrying out amidation reaction on a compound shown as a formula II and an amino acid ester in the presence of a catalyst, a solvent and alkali to obtain a compound shown as a formula I, wherein R is an amino acid ester residue;

in the formula II, X is the same as the definition in the formula I;

the amino acid ester is a product obtained by esterification reaction of carboxyl in amino acid residue and alcohol.

In the amidation reaction step of the method, the reaction temperature is-20-150 ℃, and the reaction temperature can be-5 ℃; the time is 4 to 24 hours, and specifically 8 to 12 hours;

the feeding molar ratio of the compound shown in the formula II to the amino acid ester is 1: 1-5;

the catalyst is one of 4-dimethylamino pyridine, tributylamine and tetrabutylammonium bromide;

the charging molar ratio of the catalyst to the compound shown in the formula II is 0.01-0.05: 100, respectively;

the solvent is at least one selected from dichloromethane, ethyl acetate, chloroform, tetrachloromethane, tetrahydrofuran, N-dimethylformamide and petroleum ether;

the alkali is triethylamine, ethylenediamine, tetramethylethylenediamine, sodium tert-butoxide or n-butyllithium;

the charging molar ratio of the alkali to the compound shown in the formula II is 1-15: 1;

the alkali is added into the reaction system in a dropwise manner; the dropping speed is 1 ml/min-5 ml/min.

The invention provides a method for preparing a compound shown as a formula I, wherein R is an amino acid residue, which comprises the following steps:

carrying out carboxyl deprotection reaction on the compound shown in the formula I with the R as the amino acid ester residue in the presence of a solvent and alkali to obtain the compound shown in the formula I with the R as the amino acid residue;

in the step of carboxyl deprotection reaction, the temperature is 20-50 ℃; the time is 4 to 24 hours;

the feeding molar ratio of the compound shown in the formula I and the alkali, wherein R is amino acid ester residue, to the alkali is 1: 1-5;

the alkali is selected from at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, potassium carbonate, potassium bicarbonate, sodium carbonate and sodium bicarbonate;

the solvent is at least one selected from dichloromethane, ethyl acetate, tetrahydrofuran, methanol, water, N-dimethylformamide and petroleum ether.

In addition, the application of the compound of formula I in regulating the plant growth activity and the plant growth activity regulator containing the compound of formula I also belong to the protection scope of the invention.

Specifically, the plant growth activity is adjusted to improve at least one of the cold resistance, drought resistance, salt resistance, high temperature resistance and weeding activity of the plant;

the plant growth activity regulator is a regulator for improving at least one of cold resistance, drought resistance, salt resistance, high temperature resistance and herbicidal activity of plants.

The plant is wheat, rice, corn or cotton;

in the weeding activity, the grass is barnyard grass, goosegrass herb, alopecurus, purslane, crab grass or chenopodium album.

The high temperature is 28-38 ℃ in the high temperature resistance; more specifically, at 28-38 deg.C for several days, such as 3-6 days; more specifically, the temperature is maintained at 38 ℃ in the daytime and 28 ℃ in the nighttime for several days, such as 3-6 days.

The naphthalenesulfonamide compound shown in the formula I has the advantages of simple structure, excellent plant growth regulation activity, simple and feasible preparation method and contribution to large-scale production.

Detailed Description

The present invention will be further illustrated with reference to the following specific examples, but the present invention is not limited to the following examples. The method is a conventional method unless otherwise specified. The starting materials are commercially available from the open literature unless otherwise specified.

4-Bromomaphthalene-1-sulfonyl chloride used in the examples belowCan be prepared according to the following steps:

3.2g of potassium 4-bromonaphthalene-1-sulfonate was weighed and added to 30mL of SOCl₂Then the mixture turns white and turbid, and is heated under magnetic stirring and refluxed at 70 ℃ for 5min, and the reaction solution turns into yellow transparent liquid.

After 4h of reaction, excess SOCl was distilled off₂Obtaining a light yellow viscous liquid, adding about 20mL of chloroform, and carrying out rotary evaporation to remove residual SOCl₂(spin-steaming should be carried out without water in advance) to obtain a light yellow pasty solid. Adding a certain amount of acetone for recrystallization, carrying out suction filtration, and carrying out rotary evaporation to obtain a yellowish-brown solid.

The tyrosine dimethyl esters used in the following examples were prepared as follows:

6.66g of serine was weighed, 80mL of methanol was added, the reaction solution was cloudy, and cooled to 0 ℃ in an ice-water bath.

To the above solution was slowly added dropwise 15mL of SOCl₂And the temperature rise is prevented.

After the dropwise addition, the reaction is returned to room temperature (or the temperature is controlled by heating to be 20-30 ℃), the reaction is carried out until the solid is dissolved, the reaction progress is monitored by TLC, and the reaction is developed by 0.2% ninhydrin ethanol solution.

After the reaction was complete, the solvent was removed by evaporation, and 10mL of CHCl was added₃Suspension steaming to obtain white solid.

Example 1 preparation of methyl ((4-bromonaphthalen-1-yl) sulfonyl) serine (Compound 9)

1.6g (10mmol) of serine methyl ester are weighed out and 30mL of solvent CH are added₂Cl₂3.06g (10mol) of 4-bromonaphthalene-1-sulfonyl chloride and a catalytic amount (0.03% of the molar amount of 4-bromonaphthalene-1-sulfonyl chloride) of 4-dimethylaminopyridine were cooled to 0 ℃ in an ice-water bath. 3.0g (0.03mol) Et was added dropwise to the above solution at a rate of 1ml/min₃Amidation was carried out overnight at N, 0 ℃ and the progress of the reaction was monitored by TLC. After the reaction is finished, filtering to remove white solid, performing column chromatography after the mother liquor is suspended and steamed, wherein the eluent is petroleum ether, ethyl acetate (V/V) is 5:1, the elution volume is 2L and is 10 times of the column volume, and the obtained product is a target product ((4-bromonaphthalene-1-yl) sulfonyl) serine methyl ester with a structure belonging to formula I through structure confirmation (related data are shown as a compound 9 in a table 1), wherein X is bromine; r is serine methyl ester group.

EXAMPLE 2 preparation of ((4-bromonaphthalen-1-yl) sulfonamide) serine (Compound 10)

1.7g (4.4mmol) of ((4-bromonaphthalen-1-yl) sulfonyl) serine methyl ester prepared in example 1 was weighed, 20mL of an aqueous solution of LiOH (containing 3.0g (71.6mmol) of LiOH) and 60mL of methanol were added, and the carboxyl group deprotection reaction was carried out at 70 ℃ under reflux with heating, and the progress of the reaction was monitored by TLC. After the reaction was completed for 12 hours, the pH was adjusted to 4.0 with 1N hydrochloric acid, and methanol was removed by suspension evaporation. Using 50mLCH₂Cl₂The solution was extracted and suspended for 3 times, and the organic phase was retained. Anhydrous Na for organic phase₂SO₄Drying overnight, collecting mother liquor by suction filtration, and obtaining white solid after suspension evaporation of the mother liquor. The obtained product is confirmed by the structure (the related data are shown in a compound 10 in a table 1), and is the target product ((4-bromonaphthalene-1-yl) sulfamide) serine with the structure belonging to the formula I, wherein X is bromine; r is a serine residue.

By referring to the preparation methods provided in examples 1 and 2, compounds belonging to formula I in Table 1 except for Compound 19 can be prepared by substituting the corresponding substituents.

The structural formulas and the structural confirmation data of the compounds 1 to 16 are shown in Table 1.

TABLE 1, chemical structures of Compounds 1-16 and¹HNMR data

Example 3 determination of the biological Activity of Compounds to increase Cold tolerance in Rice (Nipponbare, group of Rice, college of agriculture, China university)

Spraying moisture on the seedling tray, spreading a little vermiculite (water absorption and moisture retention) in the holes for paving, spraying water again, sowing, paying attention to that the roots face downwards, the tray bottom is contacted, the buds face upwards, spreading the vermiculite to bury the seeds, treating 30 seeds each, and repeating 5 times. And spraying water to maintain water content. More vermiculite is scattered to prevent the water from evaporating prematurely. After sowing, the bottom of the plate is covered with shallow water (30 mass percent of nutrient solution, the specific components are shown in table 3). Water was sprayed on the seedling trays daily to maintain moisture. Placing the seedling tray in an artificial greenhouse at 20-30 ℃, illuminating for 16h, and darkness for 8h, and humidity of 70-80%. When the rice seedlings grow to the 3-leaf stage, the leaves are respectively sprayed with clear water, 100 mu M ABA and the compound (such as the compound 1) shown in the formula I, the leaves are sprayed for 24 hours, then the leaves are placed in an artificial climate chamber (the temperature is 5 ℃, the relative humidity is 70-80%, the illumination is 12 hours, and the darkness is 12 hours) for treatment for 4 days, then the leaves are placed at the normal temperature for recovery for 2 days, and the survival rate of the rice seedlings is measured.

The test was carried out as above by replacing compound 1 with compounds 2 to 16, and the test was repeated 3 times for each compound, and the results obtained are shown in Table 2.

TABLE 2 influence of Compounds on survival of Rice seedlings under Low temperature stress

TABLE 3 Rice hydroponics nutrient solution formula

As can be seen from Table 2, ABA can improve the survival rate of rice seedlings under low-temperature stress, the survival rate is up to more than 80%, most of the compounds shown in the formula I have certain activity, the compounds 11, 12, 13, 15 and 16 have good activity, and the survival rate of the rice seedlings is improved by more than 60%, wherein the survival rate of the rice seedlings treated by the compound 16 is more than 70%, and the compounds have good low-temperature-resistant activity for inducing the rice seedlings.

Example 4 determination of biological Activity of Compounds to improve drought tolerance in maize

400 corn seeds (Zhengdan 958, available from Beijing Si agricultural Co., Ltd.) with regular and full size were selected and treated with 300mL of 10% H₂O₂Soaking in water solution for 15min, sterilizing, washing seeds with a large amount of sterile water to remove residual H₂O₂And soaking the seeds in 300mL of sterile water for 24 hours for accelerating germination. Sowing the maize seeds after germination acceleration into quartz sand, covering the quartz sand with a black plastic bag, and periodically supplementing water. And (3) removing the black plastic bag after the seeds germinate, and carrying out normal culture under the conditions of illumination for 16 hours, darkness for 8 hours and temperature of 23-28 ℃, transplanting seedlings when the seedlings grow to be one leaf and one heart, carrying out water culture, wherein the components of the nutrient solution are shown in table 5, and the nutrient solution is replaced every three days. When seedlings grow to have two leaves and one core, respectively spraying clear water, 100 mu M ABA and the compound (such as the compound 1) shown in the formula I on leaf surfaces, carrying out drought stress after applying the pesticide for 24h, adding 20% PEG6000, treating for 14d, taking the whole corn, then putting the corn in a 105 ℃ forced air drying box for deactivation of enzymes for 15min, drying at 80 ℃ to constant weight, and weighing the dry weight of the corn.

The test was carried out as above by replacing compound 1 with compounds 2 to 16, and the test was repeated 3 times for each compound, and the results obtained are shown in Table 4.

TABLE 4 Effect of Compounds on corn Dry weight under drought stress

TABLE 5 corn hydroponics nutrient solution formula

Composition of mother liquor	The formula of the reagent	Concentration of nutrient solution (mmol/L)
			Potassium nitrate	KNO3	2.00
Calcium chloride	CaCl2(CaCl2、2H2O)	1.00
			Magnesium sulfate	MgSO4·7H2O	0.50
Potassium dihydrogen phosphate	KH2PO4	0.10
			Ethylenediaminetetraacetic acid ferric sodium salt	EDTA·FeNa	0.10
Boric acid	H3BO3	0.03000
			Zinc sulfate	ZnSO4·7H2O	0.00250
Copper sulfate	CuSO4·5H2O	0.00080
			Manganese sulfate	MnSO4·H2O	0.00500
Ammonium molybdate	(NH4)6Mo7O24·4H2O	0.00003

As can be seen from Table 4, the biomass of the corn can be reduced due to drought stress, the biomass of the corn can be obviously improved after ABA and the compound are sprayed, the dry weight of the corn sprayed with ABA is 33.113g, the activity is the best, and the activity of the compound 5 is 30.846g and the activity of the compound 13 is 31.157g respectively, which shows that the compound has good activity of inducing the drought resistance of the corn.

Example 5 biological Activity assay of Compounds to increase salt tolerance in Cotton (CCSI41, available from Mitsuba)

All the tests are completed in an illumination culture room of a transgenic base in the western school district of Chinese agriculture university, greenhouse water culture tests are adopted, random block arrangement is carried out, 5 treatments are carried out totally, and the test is repeated for 5 times. The culture conditions in the culture chamber are 14h (30 ℃) in light and 10h (25 ℃) in dark, and the light intensity is 450 mu mol m^-2s^-1. Delinting cotton seeds with concentrated sulfuric acid, and then delinting with 10% H₂O₂Soaking in water solution for 15min for sterilization. And soaking the disinfected seeds in sterilized water for 12h under a greenhouse condition, and germinating in sand subjected to high-temperature sterilization in advance. After the cotyledons of the two leaves are completely unfolded (6d), seedlings with consistent growth are selected and transplanted into plastic pots with the diameter of 35cm multiplied by 27cm multiplied by 12cm, the pots contain 4L1/2-Hogland nutrient solution, and the effective components of the nutrient solution are shown in Table 7.

The method of NaCl stress treatment was as follows: when the two cotyledons of the seedlings were fully expanded, the seedlings were transferred to tap water for acclimatization for one day and then cultured in 1/4-Hogland nutrient solution for 10 d. And (3) spraying clear water, 100 mu M ABA and the compound (such as the compound 1) shown in the formula I on leaf surfaces respectively in the last two days of the period, adding NaCl into the nutrient solution 24 hours after the application, and increasing the concentration of the NaCl in the nutrient solution by 50mM every 12 hours to finally reach the treatment concentration of 150 mM. 1/2-Hogland nutrient solution containing NaCl at the above-mentioned concentration was then used. The nutrient solution is replaced every 3d, and a certain amount of deionized water is added every day to supplement the water lost by evaporation. After 10 days of salt stress treatment, cotton was in the trilobate stage and awaited sampling for determination.

The test was carried out as above by replacing compound 1 with compounds 2 to 16, and the test was repeated 3 times for each compound, and the results obtained are shown in Table 6.

TABLE 6 Effect of Compounds on Cotton Dry weight under salt stress

TABLE 7 Cotton hydroponics nutrient solution formula

Composition of mother liquor	The formula of the reagent	Concentration of nutrient solution (g/L)
			Potassium nitrate	KNO3	0.61
Calcium nitrate	Ca(NO3)2·4H2O	0.95
			Magnesium sulfate	MgSO4·7H2O	0.49
Ammonium dihydrogen phosphate	NH4H2PO4	0.12
			Iron tartrate	C8H12FeNO12	0.005
Boric acid	H3BO3	2.86
			Zinc sulfate	ZnSO4·7H2O	0.22
Copper sulfate	CuSO4·5H2O	0.08
			Manganese chloride	MnCl2·4H2O	1.18
Molybdic acid	H2MoO4·4H2O	0.09

As can be seen from Table 6, the biomass of cotton can be reduced by salt stress, the biomass of corn can be obviously improved by spraying ABA and the compound, the dry weight of the corn sprayed with ABA is 0.66g, the activity is the best, and the activity times of the compounds 11, 15 and 16 are respectively 0.59g, 0.58g and 0.54g, which shows that the compound has good activity of inducing the cotton to resist salt.

Example 6 determination of biological Activity of Compounds to improve high temperature resistance of wheat (Jimai 22, available from institute of agricultural sciences, Shandong province)

Sowing wheat seeds in flowerpots with the diameter of 16cm and the height of 13cm, culturing by adopting a mixed matrix (matrix: soil is 1:2), culturing 70-80 grains in each pot, putting in an artificial climate incubator, and culturing in light/dark (12h/12h) at normal temperature (20 ℃ in the daytime and 15 ℃ at night). When the seedlings grow to the two-leaf one-heart stage, clear water, 100 mu M ABA and the compound (such as the compound 1) shown in the formula I are respectively sprayed on leaf surfaces, high-temperature treatment is carried out at 38 ℃ in the daytime and 28 ℃ at night after the application of the pesticide for 24 hours, the number of normal seedlings is counted at 3d, 4d, 5d and 6d after the treatment, and the survival rate of the seedlings is calculated. And (4) putting the material at the normal temperature (20 ℃ in the day and 15 ℃ in the night) at the 7 th day, recovering for 7 days, counting the number of normal seedlings again, and calculating the survival rate of the seedlings.

The test was carried out as above by replacing compound 1 with compounds 2 to 16, and the test was repeated 3 times for each compound, and the results obtained are shown in Table 8.

TABLE 8 survival rate of wheat seedlings after 7d recovery

As can be seen from Table 8, ABA can improve the survival rate of wheat seedlings under high-temperature stress, the survival rate is 52.3%, most of the compounds designed in the invention have certain activity, wherein the activity of the compounds 3, 6 and 2 is better, and the survival rate of the wheat seedlings is respectively improved by 44.1%, 44.8% and 38.3%, which shows that the compounds related to the application have good activity of inducing the wheat to resist high temperature.

Example 7 determination of herbicidal Activity of Compounds

Two layers of filter paper were placed on the bottom of a 6cm diameter disposable petri dish, and 2mL of reagent was added to each dish, using distilled water as a control. 25 full and uniform plant seeds were placed evenly in each dish and cultured in an incubator (60% light, 18h day, 25 ℃ C.; 6h night, 20 ℃ C.).

The common weeds and crops are soaked in a culture dish by using a solution (the DMSO is firstly used for dissolving the compound to prepare a mother solution with the concentration of 25mmol/L, and then the mother solution is diluted to 100 mu mol/L) of the compound shown in the formula I with the number of 1-16 provided by the invention, and the common weeds and the crops are cultured in an incubator. And counting the 3-day germination vigor and the 7-day germination rate, simultaneously carrying out visual inspection on the phytotoxicity degree, measuring the bud length and the root length of the seedlings in 3 days and 7 days, preliminarily and quantitatively evaluating the weeding effect and the safety of a compound seed soaking experiment, repeating the experiment for 3 times for each compound, and obtaining results shown in a table 9.

TABLE 9 germination percentage of seeds of Echinochloa crusgalli after soaking seeds for 7 days in 100. mu. mol/L compound solution

As can be seen from Table 9, ABA has no herbicidal activity against barnyard grass, while the part of the compounds represented by formula I provided by the present invention has herbicidal activity, wherein the activity of the compounds 4, 5, 7 and 15 is the best, and the germination rates of barnyard grass seeds are 23.45%, 29.38%, 28.39% and 28.29%, respectively, indicating that the compounds referred to in the present application have very good herbicidal activity.

Claims (11)

1. Any one of the following compounds:

、、、、、；

the above-mentionedIn, R₁Is composed ofOr；

The above-mentionedIn, R₂is-COOCH₃or-COOH;

the above-mentionedIn, R₃Is prepared from,、Or is；

The above-mentionedIn, R₄is-OCH₃or-OH.

2. A process for preparing a compound of formula I wherein R is an esterified residue of an amino acid, comprising the steps of:

carrying out amidation reaction on a compound shown as a formula II and an amino acid ester in the presence of a catalyst, a solvent and alkali to obtain a compound shown as a formula I, wherein R is an amino acid ester residue;

formula II

In the formula II, X is F, Cl, Br or I;

the amino acid ester is a product obtained by esterification reaction of carboxyl in amino acid residue and alcohol;

the catalyst is one of 4-dimethylamino pyridine, tributylamine and tetrabutylammonium bromide;

formula I

In the formula I, X is a halogen atom;

r is amino acid ester residue;

wherein the amino acid ester residue is a group obtained by esterification reaction of carboxyl in the amino acid residue and alcohol;

and the compounds of formula I do not include the following:

、、、、and；

in the formula I, X is F, Cl, Br or I;

the amino acid ester residue is a group obtained by esterification reaction of carboxyl in the following amino acid residues and alcohol:

a residue of alanine, valine, leucine, isoleucine, proline, phenylalanine, tryptophan, methionine, glycine, serine, threonine, cysteine, tyrosine, asparagine, glutamine, lysine, histidine, aspartic acid, glutamic acid, or 1-aminocyclopropanecarboxylic acid;

the alcohol is a monohydric alkyl alcohol or a dihydric alkyl alcohol.

3. The method of claim 2, wherein: the alcohol is methanol, ethanol, n-propanol, isopropanol or tert-butanol.

4. The method of claim 3, wherein: the amino acid ester residue is serine methyl ester.

5. The process according to any one of claims 2 to 4, wherein in the amidation step, the reaction temperature is-20 ℃ ~ 150 ℃ for 4h ~ 24 h;

the feeding molar ratio of the compound shown in the formula II to the amino acid ester is 1: 1 ~ 5;

the feeding molar ratio of the catalyst to the compound shown in the formula II is 0.01 ~ 0.05.05: 100;

the solvent is selected from dichloromethane, ethyl acetate, chloroform, tetrachloromethane, tetrahydrofuran,N, N-at least one of dimethylformamide and petroleum ether;

the alkali is triethylamine, ethylenediamine, tetramethylethylenediamine, sodium tert-butoxide or n-butyllithium;

the charging molar ratio of the alkali to the compound shown in the formula II is 1 ~ 15: 1;

the alkali is added into the reaction system in a dropping mode, and the dropping speed is 1ml/min ~ 5 ml/min.

6. The process according to claim 5, wherein the amidation step is carried out at a reaction temperature of-5 ℃ ~ 5 ℃ for a period of 8h ~ 12 h.

7. A process for preparing a compound of formula I wherein R is an amino acid residue, comprising the steps of:

carrying out carboxyl deprotection reaction on a compound shown as a formula I with R as an amino acid ester residue in the presence of a solvent and alkali to obtain the compound shown as the formula I with R as the amino acid residue;

formula I

In the formula I, X is a halogen atom;

r is amino acid ester residue;

wherein the amino acid ester residue is a group obtained by esterification reaction of carboxyl in the amino acid residue and alcohol;

and the compounds of formula I do not include the following:

、、、、and；

in the formula I, X is F, Cl, Br or I;

the amino acid ester residue is a group obtained by esterification reaction of carboxyl in the following amino acid residues and alcohol:

alanine, valine, leucine, isoleucine, proline, phenylalanine, tryptophan, methionine, glycine, serine, threonine, cysteine, tyrosine, asparagine, glutamine, lysine, histidine, aspartic acid, glutamic acid, or 1-aminocyclopropanecarboxylic acid.

8. The method of claim 7, wherein the carboxyl group deprotection reaction step is carried out at 20 ℃ ~ 50 ℃ for 4h ~ 24 h;

the feeding molar ratio of the compound shown in the formula I, wherein R is amino acid ester residue, to the alkali is 1: 1 ~ 5;

the alkali is selected from at least one of sodium hydroxide, potassium hydroxide, lithium hydroxide, potassium carbonate, potassium bicarbonate, sodium carbonate and sodium bicarbonate;

the solvent is selected from dichloromethane, ethyl acetate, tetrahydrofuran, methanol, water,N, N-at least one of dimethylformamide and petroleum ether.

9. Use of a compound according to claim 1 for regulating plant growth activity.

10. Use according to claim 9, characterized in that: the plant growth activity is adjusted to improve at least one of the cold tolerance, drought tolerance, salt tolerance, high temperature tolerance and weeding activity of the plant.

11. Use according to claim 9 or 10, characterized in that: the plant is wheat, rice, corn or cotton;

in the weeding activity, the grass is barnyard grass, goosegrass herb, alopecurus, purslane, crab grass or chenopodium album.