JPH09165374A - 2,6-dichloroisonicotinic phenetylamide derivative and plant disease injury controlling agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain 2,6-dichloroisonicotinic phenetylamide derivative having excellent effect on controlling various plant disease injuries due to plant pathogenic virus, bacteria and mould, free from any concern about chemical injury to plants, thus useful as a plant disease injury controlling agent. SOLUTION: This new compound is expressed by formula I [R<1> , R<2> and R<3> are each H or a lower alkyl; R<4> is H, a (halogen-substituted) lower alkyl; (halogen-substituted) lower alkoxy, (lower alkyl-substituted) amino, nitro, cyano or halogen; R<1> and R<4> , and R<2> and R<3> may each be combined into a ring; excepting that R<2> is methyl, and R<1> , R<3> and R<4> are each H], e.g. 2,6-dichloroisonicotinic phenetylamide. The compound of formula I is obtained by reaction of 2.6- dichloroisonicotinic acid chloride of formula II with a compound of formula III in a solvent in the presence of a base.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a 2,6-dichloroisonicotinic acid phenethylamide derivative, which is useful as an agricultural chemical.

[0002]

2. Description of the Prior Art Regarding 2,6-dichloroisonicotinic acid phenethylamide derivatives, Zh. Org. Khi
m. , 3 (6), 1117 (1967), and Zh. O
bshch. Khim. , 39 (1), 26 (196
9) describes the synthesis of 2,6-dichloro-N- (α-methylphenethyl) -isonicotinic acid amide. However, there is no description about the use as a plant disease controlling agent. Patent application inventions relating to isonicotinic acid derivatives include, for example, JP-A-63-93766, 2,6-
It is disclosed that dihalogenated isonicotinic acid and its ester derivative are effective as a plant disease controlling agent. Further, JP-A No. 7-173012 by the present inventors discloses that 2-chloro-6-hydroxyisonicotinic acid is effective as a plant disease controlling agent.

[0003]

However, the above-mentioned compounds are not always sufficient in their efficacy, and the compounds disclosed in JP-A-63-93766 may cause phytotoxicity on plants to be protected. . Therefore, a safer and more effective drug for plants has been desired.

[0004]

Means for Solving the Problems As a result of various studies to solve such problems, the present inventors have found that a 2,6-dichloroisonicotinic acid phenethylamide derivative represented by the general formula (2) is not harmful to plants. The present invention was completed without worrying about the fact that it showed excellent plant disease control activity. That is, the present invention provides: The following general formula (1)

[0005]

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(In the formula, R ¹ represents a hydrogen atom or a lower alkyl group, R ² and R ³ each independently represent a hydrogen atom or a lower alkyl group, and R ⁴ represents a hydrogen atom, a lower alkyl group or a lower alkoxy group. Represents an amino group, a lower alkyl group-substituted amino group, a nitro group, a cyano group, a halogen atom, a halogen-substituted lower alkyl group or a halogen-substituted lower alkoxy group, and R ¹ and R ⁴ or R ² and R ³ are It is also possible to form a ring together, wherein R ² is a methyl group and R ¹ ,
Except when both R ³ and R ⁴ are hydrogen. ) 2,6-dichloroisonicotinic acid phenethylamide derivative represented by

[0007] 2. 2. In the general formula (1), 2,6-dichloroisonicotinic acid phenethylamide derivative as described in 1 above, wherein R ² is a hydrogen atom. ^3. The 2,6-dichloroisonicotinic acid phenethylamide derivative as described in 2 above, wherein in the general formula (1), R ³ is a hydrogen atom. In the general formula (1), R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom, and the 2,6-dichloroisonicotinic acid phenethylamide derivative according to any one of 1 to 3 above. ,

[0008] 5. The following general formula (2)

[0009]

Embedded image (In the formula, R ¹ represents a hydrogen atom or a lower alkyl group, and R ²
And R ³ each independently represents a hydrogen atom or a lower alkyl group, and R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, an amino group, a lower alkyl group-substituted amino group, a nitro group, a cyano group, a halogen atom, a halogen. It represents a substituted lower alkyl group or a halogen-substituted lower alkoxy group. R ¹ and R ⁴ , or R ² and R ³ may together form a ring. 5. A plant disease controlling agent, which comprises, as an active ingredient, a 2,6-dichloroisonicotinic acid phenethylamide derivative represented by 4.). In the general formula (2), R ² is a hydrogen atom,
6. the plant disease controlling agent as described above; In the above general formula (2), R ³ is a hydrogen atom.
7. The plant disease controlling agent as described above; In the general formula (2), the present invention relates to the plant disease controlling agent according to any one of 5 to 7 above, wherein R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formulas (1) and (2), R ¹ represents a hydrogen atom or a lower alkyl group,
The lower alkyl group may be linear, branched or cyclic and includes, for example, methyl group, ethyl group, n-propyl group,
Examples thereof include those having 1 to 4 carbon atoms such as isopropyl group, n-butyl group, isobutyl group, 2-butyl group, tertiary butyl group and cyclopropyl group. Preferred as R ¹ is a hydrogen atom or a lower alkyl group having 1 to 2 carbon atoms.

R ² and R ³ each independently represent a hydrogen atom or a lower alkyl group, and the lower alkyl group may be linear, branched or cyclic and includes, for example, a methyl group, an ethyl group, an n-propyl group, Examples thereof include those having 1 to 4 carbon atoms such as isopropyl group, n-butyl group, isobutyl group, 2-butyl group, tertiary butyl group and cyclopropyl group. Preferred as R ² and R ³ are a hydrogen atom or a lower alkyl group having 1 to 2 carbon atoms, and a hydrogen atom is particularly preferred.

R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, an amino group, a lower alkyl group-substituted amino group,
It represents a nitro group, a cyano group, a halogen atom, a halogen-substituted lower alkyl group or a halogen-substituted lower alkoxy group.
The lower alkyl group may be linear or branched,
For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, 2-butyl group,
Examples thereof include those having 1 to 4 carbon atoms, such as tertiary butyl groups, and preferably those having 1 to 2 carbon atoms. The lower alkoxy group has, for example, a methoxy group, an ethoxy group, an n-propoxy group and the like having 1 to 4 carbon atoms, preferably 1 carbon atom.
~ 2 are mentioned. The lower alkyl group-substituted amino group is an amino group in which a hydrogen atom of the amino group is substituted with a lower alkyl group having 1 to 4 carbon atoms, for example, a dimethylamino group,
Disubstituted compounds such as diethylamino group, methylamino group,
Examples include monosubstituted compounds such as an ethylamino group, preferably disubstituted compounds having an alkyl group having 1 to 2 carbon atoms.

The halogen atom is fluorine, chlorine, bromine,
Iodine and the like, preferably fluorine or chlorine can be mentioned. Examples of the halogen-substituted lower alkyl group include compounds in which a lower alkyl group having 1 to 4 carbon atoms is substituted with 1 to 5 halogen atoms, for example, trifluoromethyl group, trichloromethyl group, difluoromethyl group, pentafluoroethyl group and the like. And preferably an alkyl group having 1 to 3 carbon atoms and substituted with 1 to 3 halogen atoms. Examples of the halogen-substituted lower alkoxy group include compounds having 1 to 5 halogen atoms substituted on a lower alkoxy group having 1 to 4 carbon atoms, such as trifluoromethoxy group, trichloromethoxy group, difluoromethoxy group, pentafluoroethoxy group and the like. Can be mentioned.

Preferred as R ⁴ are a hydrogen atom, a lower alkyl group, a lower alkoxy group, a lower alkyl group-substituted amino group, a nitro group, a halogen atom and a halogen-substituted lower alkyl group, more preferably a hydrogen atom and a lower group. Examples thereof include an alkyl group, a lower alkoxy group, a nitro group and a halogen atom, and a hydrogen atom is particularly preferable.

R ² and R ³ may be combined to form a ring in the general formula (1) or (2). Examples of the ring formed include cyclopropyl ring, cyclopentyl ring, cycloalkyl ring such as cyclohexyl ring, and the like.
Similarly, R ⁴ and R ¹ may be combined to form a ring in the general formula (1) or (2). Examples of the ring formed include rings such as tetrahydroisoquinoline.

However, the compound represented by the general formula (1) does not include a compound in which R ₂ is a methyl group and R ₁ , R ₃ and R ₄ are all hydrogen, but in the general formula (2) The compounds shown include the compounds.

The compound represented by the general formula (1) and / or the general formula (2) in the present invention can be produced, for example, by the following method. However, the compound is not limited to these production methods. Hereinafter, for convenience of description, a method for producing the compound represented by the general formula (2) will be described. Incidentally, R ^{1 to} R ⁴ in the figure have the same meaning as the definition of the general formula 82).

[0018]

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That is, the 2,6-dichloroisonicotinic acid chloride represented by the formula (3) is reacted with the phenethylamine derivative represented by the general formula (4) in the presence of a base, if necessary, in a suitable solvent. Thus, the 2,6-dichloroisonicotinic acid phenethylamide derivative represented by the general formula (2) can be produced. Examples of the reaction solvent include ethers such as tetrahydrofuran, halogenated hydrocarbons such as chloroform and dichloroethane, and aprotic polar solvents such as N, N-dimethylformamide and dimethyl sulfoxide. Triethylamine as the base,
Organic bases such as diisopropylethylamine, pyridine, 4-dimethylaminopyridine and diazabicycloundecene, hydroxides such as sodium hydroxide and potassium hydroxide,
Carbonates such as potassium carbonate and cesium carbonate can be used. The reaction temperature will differ depending on the solvent, base, etc., but is usually −
10-80 degreeC is preferable and 0-50 degreeC is especially preferable.
The reaction time varies depending on the reaction temperature, solvent, base, etc.,
It is usually 0.1 to 10 hours, preferably 0.5 to 5 hours.

Tables 1 to 3 show specific structures of the compounds represented by the general formula (1) and / or the general formula (2) of the present invention produced by the above-mentioned method. is there. However, in the table, R _{1 to} R ₄ respectively correspond to the substituents of the general formula (1) and / or the general formula (2), Me is a methyl group, Et is an ethyl group, Pr is a propyl group, and Bu is butyl. Represents a group.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

[Table 3]

A plant disease controlling agent comprising a 2,6-dichloroisonicotinic acid phenethylamide derivative represented by the general formula (2) as an active ingredient is a plant disease controlling agent for controlling various plant diseases caused by plant pathogenic viruses, bacteria and filamentous fungi, such as rice. It can be applied to the major diseases such as blast and spot disease of cucumber, etc., but it shows an excellent effect especially against blast. The 2,6-dichloroisonicotinic acid phenethylamide derivative represented by the general formula (2) elicits a resistance reaction against a plant pathogenic fungus originally possessed by a plant, rather than expressing a direct bactericidal action against the plant pathogenic fungus. It exerts disease control by its action. Therefore, it is preferable to use this drug prophylactically as a form of use.

The present drug can be used alone as an active ingredient, but it is usually a solid or liquid carrier used in the formulation of agricultural chemicals, as well as a dispersant, a diluent, an emulsifier, a spreading agent,
It can be mixed with an auxiliary agent such as a thickener and formulated into a dosage form such as a wettable powder, a liquid preparation, an oil preparation, a powder preparation, a granule preparation, a sol preparation (flowable) and the like.

Examples of the solid and liquid carriers include talc, clay, bentonite, kaolin, diatomaceous earth, montmorillonite, mica, vermiculite, gypsum, calcium carbonate, white carbon, wood powder, starch, alumina, silicate, sugar weight. Coalescence, waxes, water, alcohols (methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, ethylene glycol, benzyl alcohol, etc.), petroleum fractions (petroleum ether, kerosene, solvent naphtha, etc.) , Aliphatic or alicyclic hydrocarbons (n-hexane, cyclohexane, etc.), aromatic hydrocarbons (benzene, toluene, xylene, ethylbenzene, chlorobenzene, cumene, methylnaphthalene, etc.), halogenated hydrocarbons (chloroform, Jiku Methane, etc.), ethers (isopropyl ether, ethylene oxide, tetrahydrofuran etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone etc.), esters (ethyl acetate, butyl acetate, ethylene glycol acetate, amyl acetate etc.), Acid amides (dimethylformamide, dimethylacetanilide, etc.), nitriles (acetonitrile, propionitrile, acrylonitrile, etc.), sulfoxides (dimethylsulfoxide, etc.), alcohol ethers (ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, etc.), etc. Is mentioned.

Examples of the auxiliary agent include nonionic surfactants (polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylphenyl ether, polyoxyethylene sorbitan alkyl ester, sorbitan alkyl ester, etc.),
Anionic surfactant (alkylbenzene sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate, aryl sulfonate, etc.), cationic surfactant (alkyl amines, polyoxyethylene alkyl amines, quaternary Ammonium salts, etc.), amphoteric surfactants (alkylaminoethylglycine, alkyldimethylbetaine, etc.), polyvinyl alcohol, hydroxypropyl cellulose, carboxymethyl cellulose, gum arabic, tragacanth gum, xanthan gum, polyvinyl acetate, gelatin, casein, sodium alginate, etc. Is mentioned.

Further, the present drug can be used in admixture with various agricultural chemicals such as agricultural and horticultural germicides, herbicides, plant growth regulators, insecticides and acaricides, and fertilizers. The content of the active ingredient in the drug varies depending on the form of preparation, application method, and other conditions. Usually, it is 0.5 to 95% (weight), preferably 2 to 70% (weight). This drug can be applied to plants (spraying), to growing soil of plants (soil application), to surface water (water application), to seeds (seed treatment), etc. Is. The application rate of this drug varies depending on the applied plant, applied disease, etc., but in the case of foliar application, the active ingredient concentration is 1 to 1.
It is preferable to apply 50 to 300 L of a solution of 0000 ppm, preferably 10 to 1000 ppm per 10 ares, and in the case of soil application and water surface application, the amount of active ingredient is 0.1 to 1000 g per 10 ares, particularly preferably 10 to 10. It is preferred to apply 100 g. In the case of seed treatment, 0.001 to 50 g per 1 kg of seeds
It is preferable to apply the active ingredient of.

[0029]

EXAMPLES The present invention will now be described with reference to synthetic examples, formulation examples and test examples, but the present invention is not limited thereto. (Synthesis Example 1) 2.06 g of β-phenethylamine, 20 ml of tetrahydrofuran (THF) and 7.1 ml of triethylamine were stirred and ice-cooled, and 3.57 g of 2,6-dichloroisonicotinic acid chloride was added to 5 ml of dichloromethane. The dissolved solution was added dropwise. The reaction solution was stirred at room temperature for 2 hours, the solvent was evaporated under reduced pressure, and diluted hydrochloric acid was added to this. The precipitate was collected by filtration, washed with water and dried to give 2,6-dichloroisonicotinic acid phenethylamide (Compound No.
1) 4.56 g was obtained (yield 91%). The melting point of the product purified by recrystallization from methanol was 120.6 ° C. Nuclear magnetic resonance spectrum (internal standard TMS, solvent DMSO
-D ₆ ) δppm 2.9 (t) 2H 3.5 (m) 2H 7.1-7.4 (m) 5H 7.9 (s) 2H

(Synthesis Examples 2 to 27) Compound Nos. 4 to 10 shown in Tables 4 to 10 were prepared in the same manner as in Synthesis Example 1 except that various reagents were used in place of β-phenethylamine. 2-27 were obtained. However, in the table, R _{1 to} R ₄ respectively correspond to the substituents of the general formula (2), Me represents a methyl group, Et represents an ethyl group, Pr represents a propyl group, and Bu represents a butyl group.

[0031]

[Table 4]

[0032]

[Table 5]

[0033]

[Table 6]

[0034]

[Table 7]

[0035]

[Table 8]

[0036]

[Table 9]

[0037]

[Table 10]

Formulation Example 1 Dust Compound No. 2 parts by weight of 2,6-dichloroisonicotinic acid phenethylamide derivative represented by 1 to 12 was mixed with 98 parts by weight of clay and pulverized to obtain a powder.

Formulation Example 2 Wettable powder Compound No. 20 parts by weight of 2,6-dichloroisonicotinic acid phenethylamide derivative represented by 1 to 12 are mixed and pulverized with 68 parts by weight of clay, 8 parts by weight of white carbon and 4 parts by weight of polyoxyethylene nonylphenyl ether, respectively, and hydrated. I used it as an agent.

(Formulation Example 3) Granules Compound No. 5 parts by weight of 2,6-dichloroisonicotinic acid phenethylamide derivative represented by 1 to 12 are mixed and pulverized with 90 parts by weight of an equal mixture of bentonite and talc and 5 parts by weight of sodium alkylbenzene sulfonate and molded into granules. did.

(Test Example 1) Rice blast control test (soil application) Described in (Formulation Example 2) on 2-leaf stage rice (variety: Aichi Asahi) bred in a pot (diameter 6 cm, height 5.5 cm) Each of the wettable powders prepared above was applied to the soil (5 mg / pot of active ingredient). After 14 days, the rice blast fungus (Pyricu)
larva oryzae) spore suspension was spray-inoculated, placed in a humid chamber at 25 ° C for 24 hours, and then sickened in a greenhouse. 10 days after inoculation of the spore suspension, the number of lesions was investigated, and controlled by the following formula. The value was calculated. As a control drug, 2,6-dichloroisonicotinic acid methyl ester (described in JP-A-63-93766) was tested in the same manner. Table 1 shows the results
1 to 12.

[0042]

[Equation 1]

[0043]

[Table 11]

[0044]

[Table 12] (Note) -means that there is no phytotoxicity, and + means that phytotoxicity has occurred.

Test Example 2 Cucumber Bacterial Spot Bacterial Disease Control Test A four-leaf stage cucumber (cultivar: Tokiwa Shinchi Crawling) bred in a pot (diameter: 10 cm, height: 9 cm) was added to each water described in (Formulation Example 2). Active ingredient concentration 200pp prepared from Japanese medicine
m was sprayed with foliage. Seven days later, the suspension of the pathogenic bacteria was inoculated by spraying, left in a humidity chamber at 25 ° C for 48 hours, and then allowed to develop disease in a greenhouse. Seven days after the inoculation of the suspension of the pathogenic bacteria, the number of lesions in the lower four leaves was examined. The control value was calculated in the same manner as in (Test Example 1). As a result, Compound No. The compounds represented by 1 to 12 showed a control value of 85 to 100%. As a control drug, 2-chloro-6-hydroxyisonicotinic acid (described in JP-A No. 7-173012) was also tested by the same method and showed a control value of 60%.

[0046]

INDUSTRIAL APPLICABILITY The 2,6-dichloroisonicotinic acid phenethylamide derivative according to the present invention is useful as a plant disease controlling agent and is excellent in controlling various plant diseases caused by plant pathogenic viruses, bacteria and filamentous fungi. Indicates that there is no worry of chemical damage to plants.

Claims (8)

[Claims] [Claim 1] The following general formula (1) (In the formula, R ¹ represents a hydrogen atom or a lower alkyl group, and R ²
And R ³ each independently represents a hydrogen atom or a lower alkyl group, and R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, an amino group, a lower alkyl group-substituted amino group, a nitro group, a cyano group, a halogen atom, a halogen. It represents a substituted lower alkyl group or a halogen-substituted lower alkoxy group. R ¹ and R ⁴ , or R ² and R ³ may together form a ring. Here, the case where R ² is a methyl group and all of R ¹ , R ³ and R ⁴ are hydrogen is excluded. ) 2,6
-Dichloroisonicotinic acid phenethylamide derivative. 2. The 2,6-dichloroisonicotinic acid phenethylamide derivative according to claim 1, wherein R ² in the general formula (1) is a hydrogen atom. 3. The 2,6-dichloroisonicotinic acid phenethylamide derivative according to claim 2, wherein R ³ in the general formula (1) is a hydrogen atom. 4. In the general formula (1), R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom, and 2,6- Dichloroisonicotinic acid phenethylamide derivative. 5. The following general formula (2): (In the formula, R ¹ represents a hydrogen atom or a lower alkyl group, and R ²
And R ³ each independently represents a hydrogen atom or a lower alkyl group, and R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, an amino group, a lower alkyl group-substituted amino group, a nitro group, a cyano group, a halogen atom, a halogen. It represents a substituted lower alkyl group or a halogen-substituted lower alkoxy group. R ¹ and R ⁴ , or R ² and R ³ may together form a ring. ) A plant disease control agent containing, as an active ingredient, a 2,6-dichloroisonicotinic acid phenethylamide derivative represented by 6. The plant disease controlling agent according to claim 5, wherein in the general formula (2), R ² is a hydrogen atom. 7. The plant disease controlling agent according to claim 6, wherein in the general formula (2), R ³ is a hydrogen atom. 8. The plant disease controlling agent according to claim 5, wherein in the general formula (2), R ⁴ is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom. .