CN113004240A

CN113004240A - Benzopyran compound and application thereof in pesticides

Info

Publication number: CN113004240A
Application number: CN202110263879.9A
Authority: CN
Inventors: 唐孝荣; 蒋文静; 严映坤; 程玮; 肖婷婷; 陆童; 张婷婷; 王静文; 刘佩; 李海
Original assignee: Xihua University
Current assignee: Yichang Shentong Technology Co ltd
Priority date: 2021-03-11
Filing date: 2021-03-11
Publication date: 2021-06-22
Anticipated expiration: 2041-03-11
Also published as: CN113004240B

Abstract

The invention relates to benzopyran compounds and application thereof in pesticides, belonging to the technical field of pesticides. The invention aims to provide a benzopyran compound which can be used as an insecticide and a bactericide. The structural general formula of the benzopyran compound is shown in formula I, wherein R is₁Is a hydrogen atom, a halogen atom, a C1-C4 alkyl group or a C1-C4 alkoxy group; r₂Is hydrogen atom, halogen atom, C1-C4 alkyl or C1-C4 alkoxy. The compound has simple synthesis process, good poisoning effect on pests and good inhibition effect on plant pathogenic bacteriaThe preparation method lays a good foundation for the creation of new pesticides.

Description

Benzopyran compound and application thereof in pesticides

Technical Field

The invention relates to benzopyran compounds and application thereof in pesticides, belonging to the technical field of pesticides.

Background

As a traditional big agricultural country in China, crops are always an important support for maintaining the lives of people in China. Similarly, agricultural chemicals produced by crops are a link of great concern. Pesticides are mainly divided into three categories, i.e. herbicides, insecticides and bactericides, and with the wide application of insecticides and bactericides, the resistance of pests, germs and the like to the pesticides is continuously increased, so that more insecticides and bactericides need to be researched. In addition, with the increasing emphasis on food safety, the pursuit of green and organic properties is the current trend, and the use of pesticides is also influenced to a certain extent, and it is necessary to research novel pesticides having the characteristics of high efficiency, low toxicity, safety to non-target organisms, easy degradation in the environment, difficult generation of resistance by pests, and the like.

Benzo-heterocycles are important in the research and development of pesticides and medicines. Benzopyrans and derivatives thereof are a class of compounds with a wide range of physiological and pharmacological activities and are widely present in plants in nature. For many years, a great deal of research work has been carried out in this field, and particularly the synthesis of benzopyran derivatives and their research on pharmacology has been abnormally active. Many high-efficiency and low-toxicity medicinal compounds are synthesized by various methods, but reports of applying benzopyran and derivatives thereof as active compounds to pesticide research are few.

Meanwhile, benzopyran-containing compounds are generally characterized by high efficiency, low toxicity, safety to non-target organisms, easy degradation in the environment, difficult generation of resistance by pests, and the like, and compounds with novel structures and excellent performance are continuously available. Therefore, in the research and development process of pesticides, benzopyran-containing compounds will receive more extensive attention and become hot spots and frontiers for creating new pesticides.

To date, there has been no report of the use of benzopyran compounds as pesticides and fungicides.

Disclosure of Invention

In view of the above defects, the technical problem to be solved by the present invention is to provide a benzopyran compound which can be used as an insecticide and a bactericide.

The structural general formula of the benzopyran compound is shown as formula I:

wherein R is₁Is a hydrogen atom, a halogen atom, a C1-C4 alkyl group or a C1-C4 alkoxy group; r₂Is hydrogen atom, halogen atom, C1-C4 alkyl or C1-C4 alkoxy.

In some embodiments of the invention, R₁Is hydrogen atom, chlorine atom, bromine atom, methyl or methoxy; r₂Is hydrogen atom, fluorine atom, chlorine atom, bromine atom, methyl or methoxyl.

In some embodiments of the invention, R₁Is a hydrogen atom or a chlorine atom; r₂Is a fluorine atomChlorine atom, methyl group or methoxy group.

In some embodiments of the invention, the compound has the structural formula:

the invention also provides application of the benzopyran compound in preparing agricultural fungicides.

The benzopyran compound has good bactericidal activity and can be used for preparing agricultural bactericides.

In some embodiments, the bacteria controlled by the agricultural fungicide are bacteria.

In some embodiments, the bacteria controlled by the agricultural fungicide are rice bacterial blight, cabbage soft rot, sweet potato blast, kiwifruit canker or tobacco bacterial wilt.

The invention also provides application of the benzopyran compound in preparing agricultural pesticides.

The benzopyran compound has good insecticidal activity and can be used for preparing agricultural insecticides.

In some embodiments, the pest controlled by the agricultural pesticide is armyworm, tetranychus cinnabarinus or aphis fabae.

Compared with the prior art, the invention has the following beneficial effects:

the benzopyran compounds are synthesized, active compounds or active lead compounds with novel structures and excellent activity are found, the compound is simple in synthesis process, has a good poisoning effect on pests, has a good inhibition effect on plant pathogenic bacteria, and lays a good foundation for creating new pesticides.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of the compound of example 1.

FIG. 2 is a partial enlarged view of the nuclear magnetic hydrogen spectrum of the compound of example 1.

FIG. 3 is a nuclear magnetic carbon spectrum of the compound of example 1.

FIG. 4 is a high resolution mass spectrum of the compound of example 1.

FIG. 5 is a nuclear magnetic hydrogen spectrum of the compound of example 2.

FIG. 6 is a partial enlarged view of the nuclear magnetic hydrogen spectrum of the compound of example 2.

FIG. 7 is a nuclear magnetic carbon spectrum of the compound of example 2.

FIG. 8 is a high resolution mass spectrum of the compound of example 2.

FIG. 9 is a nuclear magnetic hydrogen spectrum of the compound of example 3.

FIG. 10 is a partial enlarged view of the nuclear magnetic hydrogen spectrum of the compound of example 3.

FIG. 11 is a nuclear magnetic carbon spectrum of the compound of example 3.

FIG. 12 is a high resolution mass spectrum of the compound of example 3.

FIG. 13 is a nuclear magnetic hydrogen spectrum of the compound of example 4.

FIG. 14 is a partial enlarged view of a nuclear magnetic hydrogen spectrum of the compound of example 4.

FIG. 15 is a nuclear magnetic carbon spectrum of the compound of example 4.

FIG. 16 is a high resolution mass spectrum of the compound of example 4.

FIG. 17 is a nuclear magnetic hydrogen spectrum of the compound of example 5.

FIG. 18 is a partial enlarged view of a nuclear magnetic hydrogen spectrum of the compound of example 5.

FIG. 19 is a nuclear magnetic carbon spectrum of the compound of example 5.

FIG. 20 is a high resolution mass spectrum of the compound of example 5.

FIG. 21 is a nuclear magnetic hydrogen spectrum of the compound of example 6.

FIG. 22 is a close-up view of the nuclear magnetic hydrogen spectrum of the compound of example 6.

FIG. 23 is a nuclear magnetic carbon spectrum of the compound of example 6.

FIG. 24 is a high resolution mass spectrum of the compound of example 6.

Detailed Description

The benzopyran compound has a structural general formula shown in formula I:

In the present invention, the "C1-C4 alkyl group" means a straight-chain or branched alkyl group having 1 to 4 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, etc.

"C1-C4 alkoxy" refers to a straight or branched chain alkoxy group having 1 to 4 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, and the like.

In some embodiments of the invention, R₁Is a hydrogen atom or a chlorine atom; r₂Is fluorine atom, chlorine atom, methyl or methoxyl.

In some embodiments of the invention, the benzopyran-based compound has the structural formula:

the benzopyran compound can be prepared by adopting the conventional method in the field.

In some embodiments of the invention, benzopyrans are synthesized using the following route:

The following examples are provided to further illustrate the embodiments of the present invention and are not intended to limit the scope of the present invention.

The synthetic route adopted in the examples is:

example 1

Compound (I)

The preparation of (1):

adding 10mmol of 4-fluoroacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 5-chlorosalicylaldehyde into the reaction mixture, continuing to react for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

10mmol of the home-made intermediate was dissolved in 20mL of N, N-Dimethylformamide (DMF) and 10mmol of K was added₂CO₃Then, a mixed solution of 10mmol of malononitrile and 20mL of DMF was slowly dropped into the above solution through a constant pressure dropping funnel. Reacting for 4-6 h under the condition of stirring at 40-45 ℃, and checking whether the reaction is finished by TLC. After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. Recrystallizing the obtained crude product by using absolute ethyl alcohol to obtain a target compound, wherein the physical and chemical properties of the target compound are as follows:

brown crystals; the yield is 87%;¹H NMR(400MHz,DMSO-d₆)δ(ppm):8.02(2H,dd,J＝8.8,6.0Hz),7.41(1H,d,J＝2.4Hz),7.32(2H,t,J＝8.4Hz),7.27(1H,dd,J＝8.8,2.4Hz),7.01(1H,d,J＝8.8Hz),6.91(2H,s),4.11(1H,t,J＝5.2Hz),3.44(2H,dd,J＝5.2,2.0Hz)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):196.80,165.52(d,J＝250.0Hz),161.79,148.71,133.89(d,J＝3.0Hz),131.53(d,J＝9.0Hz),128.41,128.29,128.21,126.43,120.70,118.13,116.10(d,J＝22.0Hz),54.20,46.63,31.36；HRMS(ESI)m/z:Calcd for C₁₈H₁₂N₂O₂FCl[M+Na]⁺:365.0464,Found:365.0456.

the nuclear magnetic hydrogen spectrum of the compound is shown in figure 1, and the overlapped or dense part in figure 1 is shown in figure 2 in detail. The nuclear magnetic carbon spectrum of the compound is shown in fig. 3, and a partial enlarged view of overlapped or dense parts in the nuclear magnetic carbon spectrum is also shown in fig. 3. The high resolution mass spectrum of this compound is shown in FIG. 4.

Example 2

Compound (I)

The preparation of (1):

adding 10mmol of 4-fluoroacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 3, 5-dichlorosalicylaldehyde into the reaction mixture, continuing to react for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

10mmol of the home-made intermediate was dissolved in 20mL DMF and 10mmol K was added₂CO₃Then, a mixed solution of 10mmol of malononitrile and 20mL of DMF was slowly dropped into the above solution through a constant pressure dropping funnel. Reacting for 4-6 h under the condition of stirring at 40-45 ℃, and checking whether the reaction is finished by TLC. After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. Recrystallizing the obtained crude product by using absolute ethyl alcohol to obtain a target compound, wherein the physical and chemical properties of the target compound are as follows:

a yellow powder; the yield is 85 percent;¹H NMR(400MHz,DMSO-d₆)δ(ppm):8.01(2H,dd,J＝8.8,5.6Hz),7.75(1H,d,J＝2.0Hz),7.56(1H,d,J＝2.4Hz),7.32(2H,t,J＝8.8Hz),7.05(2H,s),4.12(1H,t,J＝5.2Hz),3.52(1H,dd,J＝17.2,5.6Hz),3.43(1H,dd,J＝17.2,4.8Hz)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):196.68,165.57(d,J＝251.0Hz),161.33,144.92,133.80(d,J＝3.0Hz),131.53(d,J＝9.0Hz),128.36,128.28,128.07,127.20,121.47,120.28,116.11(d,J＝22.0Hz),54.46,46.22,31.71；HRMS(ESI)m/z:Calcd for C₁₈H₁₁N₂O₂FCl₂[M+Na]⁺:399.0074,Found:399.0070.

the nuclear magnetic hydrogen spectrum of the compound is shown in figure 5, and the overlapped or dense part in figure 5 is shown in figure 6 in detail. The NMR spectrum of the compound is shown in FIG. 7, and a close-up view of the overlapped or dense part of the NMR spectrum is also shown in FIG. 7. The high resolution mass spectrum of this compound is shown in FIG. 8.

Example 3

Compound (I)

The preparation of (1):

adding 10mmol of 4-chloroacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 5-chlorosalicylaldehyde into the reaction mixture, continuing to react for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

a light yellow powder; the yield is 88%;¹H NMR(400MHz,DMSO-d₆)δ(ppm):7.95(2H,d,J＝8.8Hz),7.57(2H,d,J＝8.8Hz),7.42(1H,d,J＝2.4Hz),7.27(1H,dd,J＝8.8,2.4Hz),7.01(1H,d,J＝8.8Hz),6.94(2H,s),4.11(1H,t,J＝5.6Hz),3.50-3.40(2H,m)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):196.79,154.91,143.96,137.29,134.45,129.05,128.33,127.66,127.52,126.13,122.98,122.90,114.93,54.64,48.13,36.75；HRMS(ESI)m/z:Calcd for C₁₈H₁₂N₂O₂Cl₂[M+H]⁺:359.0354,Found:359.0356.

the nuclear magnetic hydrogen spectrum of the compound is shown in figure 9, and the overlapped or dense part in figure 9 is shown in detail in figure 10. The nuclear magnetic carbon spectrum of the compound is shown in fig. 11, and a partial enlarged view of overlapped or dense parts in the nuclear magnetic carbon spectrum is also shown in fig. 11. The high resolution mass spectrum of the compound is shown in figure 12.

Example 4

Compound (I)

The preparation of (1):

adding 10mmol of 4-chloroacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 3, 5-dichlorosalicylaldehyde into the reaction mixture, continuing to react for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

a yellow powder; the yield is 89%;¹H NMR(400MHz,DMSO-d₆)δ(ppm):8.04-8.00(2H,m),7.55(1H,s),7.43(1H,s),7.33(2H,t,J＝8.4Hz),7.06(2H,s),4.14(1H,s),3.52(1H,dd,J＝17.6,5.2Hz),3.46(1H,dd,J＝17.6,4.8Hz)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):196.70,161.44,133.68,131.59,131.49,130.65,129.74,128.39,120.30,116.45,116.23,116.01,110.80,56.49,54.53,31.76；HRMS(ESI)m/z:Calcd for C₁₈H₁₁N₂O₂Cl₃[M+H]⁺:392.9964,Found:392.9920.

the nuclear magnetic hydrogen spectrum of the compound is shown in FIG. 13, and the overlapped or dense part in FIG. 13 is shown in detail in FIG. 14. The nmr spectrum of the compound is shown in fig. 15, and a close-up view of the overlapping or dense part of the nmr spectrum is shown in fig. 15. The high resolution mass spectrum of this compound is shown in FIG. 16.

Example 5

Compound (I)

The preparation of (1):

adding 10mmol of 4-methylacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 3, 5-dichlorosalicylaldehyde into the reaction mixture, continuing the reaction for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

a white powder; the yield is 87%;¹H NMR(400MHz,DMSO-d₆)δ(ppm):7.83(2H,d,J＝8.4Hz)7.55(1H,d,J＝2.4Hz),7.41(1H,d,J＝2.4Hz),7.31(2H,d,J＝8.0Hz),7.04(2H,s),4.12(1H,t,J＝5.2Hz),3.48(1H,dd,J＝17.6,5.6Hz),3.42(1H,dd,J＝17.2,5.2Hz),2.37(3H,s)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):197.53,161.30,144.92,144.20,134.62,129.67,128.59,128.33,128.24,128.22,127.17,121.46,120.29,54.56,46.11,31.72,21.60；HRMS(ESI)m/z:Calcd for C₁₉H₁₄N₂O₂Cl₂[M+Na]⁺:395.0325,Found:395.0318.

the nuclear magnetic hydrogen spectrum of the compound is shown in FIG. 17, and the overlapped or dense part in FIG. 17 is shown in detail in FIG. 18. The NMR spectrum of the compound is shown in FIG. 19, and a partial enlarged view of the overlapped or dense part of the NMR spectrum is also shown in FIG. 19. The high resolution mass spectrum of the compound is shown in figure 20.

Example 6

Compound (I)

The preparation of (1):

adding 10mmol of 4-methoxyacetophenone into 40mL of 10% NaOH aqueous solution, stirring for 30 minutes at 40-45 ℃, adding 10mmol of 3, 5-dichlorosalicylaldehyde into the reaction mixture, continuing the reaction for 10-15 hours, and checking whether the reaction is finished by using a thin-layer silica gel plate (TLC). After completion of the reaction, the reaction mixture was poured into ice water, the pH of the solution was adjusted to neutral with 10% hydrochloric acid solution, and a solid was precipitated, filtered, and washed with distilled water. The obtained crude product is recrystallized by absolute ethyl alcohol to obtain a chalcone intermediate.

a yellow powder; the yield is 92 percent;¹H NMR(400MHz,DMSO-d₆)δ(ppm):7.91(2H,d,J＝8.8Hz),7.54(1H,d,J＝2.4Hz),7.40(1H,d,J＝2.4Hz),7.05(2H,s),7.01(2H,d,J＝8.8Hz),4.12(1H,t,J＝5.2Hz),3.84(3H,s),3.47-3.37(2H,m)；¹³C NMR(100MHz,DMSO-d₆)δ(ppm):196.42,163.66,161.75,148.68,130.84,130.12,128.36,128.24,128.17,126.64,120.77,118.13,114.30,56.00,54.32,46.31,31.39；HRMS(ESI)m/z:Calcd for C₁₉H₁₄N₂O₃Cl₂[M+Na]⁺:377.0663,Found:377.0650.

the nuclear magnetic hydrogen spectrum of the compound is shown in FIG. 21, and the overlapped or dense part in FIG. 21 is shown in detail in FIG. 22. The nuclear magnetic carbon spectrum of the compound is shown in fig. 23, and a partial enlarged view of overlapped or dense parts of the nuclear magnetic carbon spectrum is also shown in fig. 23. The high resolution mass spectrum of this compound is shown in FIG. 24.

Test example 1 measurement of insecticidal Activity of the Compound of the present invention

(1) Test pest

Armyworm larvae of 3 rd age, tetranychus cinnabarinus adults, and Aphis fabae of 3 rd age, all of which are sensitive strains bred indoors all year round.

(2) Method for measuring armyworm

Dissolving a sample to be detected in dimethyl sulfoxide, diluting the sample to a certain concentration by using 0.1% Tween-80 aqueous solution, and taking a corresponding solution without the sample to be detected as a negative control. Cutting corn leaves into 2 multiplied by 4cm small sections, soaking the small sections in a solution to be detected for 5s, taking the small sections out, draining the small sections, putting the small sections into a culture dish (6cm) with filter paper paved at the bottom, inoculating 15 larvae of 3 years old, further placing the small sections in a laboratory with the temperature of 22-24 ℃, the relative humidity of 60% and the illumination time of 14:10h for continuous breeding, recording the death condition after 24h, repeating each experiment for 3 times, and calculating and correcting the death rate by using the following formula:

(3) method for determining tetranychus cinnabarinus

Dissolving a sample to be detected in dimethyl sulfoxide, diluting the sample to a certain concentration by using 0.1% Tween-80 aqueous solution, and taking a corresponding solution without the sample to be detected as a negative control. Collecting kidney bean leaves with high insect population density, carefully selecting to enable healthy adult mites (30-50 heads) to remain on leaf surfaces, soaking the kidney bean leaves with the insects into a solution to be detected for 5s, taking the kidney bean leaves away, draining the kidney bean leaves, putting the kidney bean leaves into a culture dish (6cm) with filter paper paved at the bottom, placing the kidney bean leaves in a laboratory with the temperature of 22-24 ℃, the relative humidity of 60% and the illumination time of 14:10h for continuous breeding, recording the death situation after 24h, repeating each experiment for 3 times, and calculating the corrected death rate by using the following formula:

(4) method for determining aphids of broad beans

Dissolving a sample to be detected in dimethyl sulfoxide, diluting the sample to a certain concentration by using 0.1% Tween-80 aqueous solution, and taking a corresponding solution without the sample to be detected as a negative control. Collecting broad bean leaves with high insect population density, carefully selecting healthy 3-year-old aphids (30-40 heads) to stay on the leaf surfaces, immersing the broad bean leaves with the insects into a solution to be detected for 5s, taking the broad bean leaves away, draining the broad bean leaves, putting the broad bean leaves into a culture dish (6cm) with filter paper paved at the bottom, placing the broad bean leaves in a laboratory with the temperature of 22-24 ℃, the relative humidity of 60% and the illumination time of 14:10h for continuous feeding, recording the death condition after 24h, repeating each experiment for 3 times, and calculating the corrected death rate by using the following formula:

(5) results of the experiment

The insecticidal results of the compounds of the present invention are shown in table 1.

TABLE 1 poisoning Activity of Compounds of the invention against test pests

^a: average of three replicates.

From Table 1 above, it is clear that the compounds of the present invention have a good poisoning activity against these pests.

Test example 2 measurement of bacteriostatic Activity of Compound of the present invention

(1) Test for plant pathogenic bacteria

Rice bacterial blight, cabbage soft rot, sweet potato pest, kiwifruit canker, and tobacco bacterial wilt.

(2) Measurement method

(a) Activation of strains: the bacterial strain to be tested is inoculated on a beef extract peptone solid medium slant and cultured overnight at 37 ℃.

(b) Preparation of bacterial suspension: inoculating a loop of activated test strain in a conical flask containing 100mL beef extract peptone liquid medium, culturing at 37 deg.C for 18h to obtain initial bacterial suspension, and diluting with sterile normal saline to appropriate concentration (10)⁶～10⁷CFU/mL) of the suspension.

(c) Determination of Minimum Inhibitory Concentration (MIC): dissolving the test compound in dimethyl sulfoxide, diluting with sterile normal saline containing 0.1% Tween-80 by two-fold dilution method to obtain solutions with different concentrations, and mixing. 1mL of the diluted sample solution was added to 19mL of a sterilized medium, and mixed well to prepare a plate. After the culture medium has solidified, the above-mentioned concentration of 10% is added by coating method⁶And culturing 200 mu L of CFU/mL bacterial suspension at 37 ℃ for 16-18 h, observing the growth condition of bacteria, taking the concentration of completely sterile growth as the MIC value of the test sample solution, and taking the corresponding solution without the test compound as a blank control.

(3) Results of the experiment

The bacteriostatic activity of the compounds of the invention is shown in table 2.

TABLE 2 inhibitory Activity of the Compounds of the present invention against plant pathogenic bacteria

From the above table 2, it can be seen that the compounds of the present invention have a good inhibitory effect on these plant pathogenic bacteria.

In conclusion, the compound has better insecticidal activity and bactericidal activity, has better poisoning effect on pests, has better inhibition effect on plant pathogenic bacteria, and provides a new choice for agricultural insecticides and bactericides.

Claims

1. Benzopyran compounds are characterized in that the structural general formula is shown as formula I:

2. The benzopyran-based compound according to claim 1, characterized in that: r₁Is hydrogen atom, chlorine atom, bromine atom, methyl or methoxy; r₂Is hydrogen atom, fluorine atom, chlorine atom, bromine atom, methyl or methoxyl.

3. The benzopyran-based compound according to claim 2, characterized in that: r₁Is a hydrogen atom or a chlorine atom; r₂Is fluorine atom, chlorine atom, methyl or methoxyl.

4. The benzopyran-based compound according to claim 1, characterized in that: the structural formula of the compound is as follows:

5. use of the benzopyran compounds according to any one of claims 1 to 4 in the preparation of agricultural fungicides.

6. Use of benzopyran compounds according to claim 5 in the preparation of agricultural fungicides, characterized in that: the bacteria for preventing and controlling the agricultural bactericide are bacteria.

7. Use of benzopyran compounds according to claim 5 in the preparation of agricultural fungicides, characterized in that: the bacteria controlled by the agricultural bactericide are rice bacterial blight, cabbage soft rot, sweet potato pest, kiwi fruit ulcer or tobacco bacterial wilt.

8. Use of the benzopyran compounds according to any one of claims 1 to 4 for the preparation of agricultural insecticides.

9. Use of benzopyran compounds according to claim 8, characterized in that: the pests controlled by the agricultural pesticide are armyworm, tetranychus cinnabarinus or aphis fabae.