JP2536767B2 - 4 (1H) -pyridinone derivative and fungicide for agriculture and horticulture - Google Patents

Description

TECHNICAL FIELD The present invention relates to a 4 (1H) -pyridinone derivative and an agricultural and horticultural fungicide containing the same as an active ingredient.

(Conventional Technology) Synthetic Comm
unication) 13 (5) 411-417 (1983),
A method for producing a 1,2,6-triphenyl-substituted 4 (1H) -pyridinone derivative by reacting ketimine with ethylphenyl propiolate is described, and various compounds are exemplified. Further, in JP-A-56-65871, 1- (substituted phenyl) -2,6-dimethyl-4 (1H) is disclosed.
-A pyridinone derivative is described, which is effective for cucumber powdery mildew and is also useful as a slime control agent. In addition, 3-methyl-1- (3
It is known that -methylphenyl) -2,6-diphenyl-4 (1H) -pyridinone derivative is effective against rice blight and rice blast. Similarly, JP-A-55-10
No. 2504 describes a 2,6-diphenyl-4 (1H) -pyridinone derivative, which is effective for rice blast and cucumber anthracnose.

(Problems to be Solved by the Invention) However, synthetic communication does not describe at all what physiological activity the described compounds have. Further, the bactericidal effect of the compounds described in the above specification is not always sufficient.

Therefore, the present inventors have focused on the 4 (1H) -pyridinone skeleton in order to develop an agricultural and horticultural fungicide having a novel structure and exhibiting a higher control effect than the compounds described in the above specification. As a result of intensive studies, they have succeeded in synthesizing the compound of the present invention and found that they have an excellent effect as a fungicide for agricultural and horticultural use, and completed the present invention.

(Means for Solving Problems) The 4 (1H) -pyridinone derivative of the present invention has the general formula [In the formula, R ¹ represents a phenyl group, a pyridine-1-oxide group or a furyl group which may be substituted with a lower alkyl group,
R ² represents a phenyl group, a pyridyl group optionally substituted with a lower alkoxy group or a furyl group optionally substituted with a lower alkyl group, X represents a halogen atom or a lower alkoxy group, and n is 0 or 1, 2 Indicates an integer. However, R ¹ and R ²
Does not represent a phenyl group at the same time. ]] Is represented.

The compounds of the present invention represented by formula (I) are shown in Table 1. The compound numbers will be referred to in the following description.

Next, a method for producing the compound of the present invention will be described.

(A) The compound of the present invention has the general formula (In the formula, R ³ represents a phenyl group or a furyl group which may be substituted with a lower alkyl group, and R ² has the same meaning as described above.) And a general pentanetrione derivative or a tautomer thereof. formula (In the formula, X and n have the same meanings as described above.) And can be produced by reacting with an aniline derivative.

The tautomer of the compound (II) shown here is represented by the following general formula.

The reaction of the pentanetrione derivative represented by the general formula (II) or its tautomer with the aniline derivative represented by the general formula (III) is generally carried out in a suitable solvent, for example, hydrocarbons such as benzene, toluene and xylene. , Halogenated hydrocarbons such as chlorobenzene, methylene chloride, chloroform, diisopropyl ether, tetrahydrofuran,
Ethers such as dioxane, acetone, methyl ethyl ketone, ketones such as cyclohexanone, esters such as ethyl acetate, nitriles such as acetonitrile, N, N-dimethylformamide, N, N-dimethylacetamide, N-
It is dissolved or suspended in an amide such as methylpyrrolidone, dimethylsulfoxide, acetic acid or the like, or in the absence of a solvent. Preferably, the reaction is carried out by dissolving in xylene or chlorobenzene. In this case, it is possible to react by adding an appropriate reaction aid. As a reaction aid to use,
Suitable acids such as mineral acids such as sulfuric acid and hydrochloric acid, organic acids such as P-toluenesulfonic acid and trifluoromethanesulfonic acid, and Lewis acids such as boron trifluoride, aluminum chloride and titanium tetrachloride can be used. In addition, it is preferable to collect the by-produced water in the Dean Stark trap.

Further, the reaction can be carried out in the presence of a dehydrating agent such as molecular sieves depending on the acid and solvent used.
For example, when using P-toluenesulfonic acid in dimethylsulfoxide, Molecular Sieves 5A can be used. The amount of molecular sieves used is usually 2 to 200 with respect to 0.1 mol of the pentathrio derivative (II).
It is in the range of g. The reaction can be carried out at any temperature from the freezing point of the solvent to the boiling point, preferably from 10 ° C. to the boiling point of the solvent.

After completion of the reaction, the compound of the present invention can be obtained by washing the acid or molecular sieves with water and an alkaline solution or removing them by filtration, extracting the reaction product with chloroform, and distilling the solvent off. If necessary, the product is purified by recrystallization from acetone, methanol, ethanol, benzene, toluene, diisopropyl ether, ethyl acetate, chloroform, hexane or the like, or by passing through silica gel column chromatography.

(B) Further, the compound of the present invention comprises a propynoic acid ester derivative represented by the general formula R ² —C≡CCOOC ₂ H ₅ (IV) (wherein R ² has the same meaning as described above) and a general formula (In the formula, X, R ³ and n have the same meanings as described above.) And can be produced by reacting with an imine derivative in the presence of a Lewis acid such as aluminum chloride or titanium tetrachloride. .

In this case, the propynoic acid ester derivative represented by the general formula (IV) and the imine derivative represented by the general formula (V) are dissolved or suspended in an appropriate solvent, for example, benzene, toluene, xylene, chlorobenzene, dimethyl sulfoxide and the like. Alternatively, the reaction is carried out without solvent. It is preferred to dissolve in toluene and add 0.5 to 5 equivalents of Lewis acid as a reaction aid. As the Lewis acid, aluminum chloride, titanium tetrachloride, boron trifluoride, boron trichloride or the like can be used, and it is particularly preferable to add 1 equivalent of aluminum chloride.

After completion of the reaction, the compound of the present invention can be obtained by washing with an aqueous solution of sulfuric acid, water and an aqueous solution of alkali, extracting with chloroform, drying and distilling off the solvent. If necessary, the product is purified by passing through silica gel column chromatography and further recrystallized with acetone, methanol, benzene, ethyl acetate, chloroform and the like.

(C) Furthermore, the pyridine N-oxide derivative of the compound of the present invention can be produced by oxidizing the pyridine derivative produced as described in (a) above.

For example, 3-methyl-1,6-diphenyl-2- (4-
When pyridyl) -4 (1H) -pyridinone is dissolved or suspended in a suitable solvent such as methylene chloride, benzene, chloroform or the like and reacted with an oxidizing agent such as m-perbenzoic acid, 4- [3 -Methyl-1,6-diphenyl-4 (1H) -pyridinon-2-yl] pyridine N-oxide is obtained.

Next, the production method of the compound of the present invention will be described with reference to Reference Examples and Examples.

Reference Example 3-methyl-1,6-diphenyl-2- (4-pyridyl)
Synthesis of -4 (1H) -pyridinone 2-Methyl-5-phenyl-1- (4-pyridyl)-
3.9 g of 1,3,5-pentanetrione and 2.6 g of aniline were dissolved in 100 ml of xylene, and 2.7 g of P-toluenesulfonic acid and 30 g of molecular sieves 5A were added. The mixture was heated under reflux for 2 hours with a Dean Stark apparatus. After cooling, the precipitate was separated from the reaction solution. The precipitate was washed with methyl alcohol and chloroform, the liquid was concentrated under reduced pressure, water was added to the residue to make it slightly alkaline with a 10% aqueous sodium hydroxide solution, and then extracted with chloroform. The chloroform layer was further washed with water and then dried over magnesium sulfate. After removing the desiccant, the solvent was distilled off under reduced pressure, and the residue was subjected to silica gel column chromatography and eluted with a mixed solvent of chloroform and methyl alcohol (10: 1). When the crystals obtained after distilling off the solvent were recrystallized from ethyl acetate and acetone,
3-Methyl-1,6-diphenyl-having a melting point of 218 to 223 ° C.
2.2 g of 2- (4-pyridyl) -4 (1H) -pyridinone was obtained.

Example 1 Synthesis of 4- [3-methyl-1,6-diphenyl-4 (1H) -pyridinon-2-yl] pyridine N-oxide (Compound 2) 3-Methyl-1,6-diphenyl-2- ( 0.9 g of 4-pyridyl) -4 (1H) -pyridinone was dissolved in chloroform, 0.7 g of m-perbenzoic acid was added, and the mixture was reacted for 4 hours while stirring. After the reaction was completed, water was added, and the mixture was made alkaline with a saturated aqueous sodium hydrogen carbonate solution and then extracted with chloroform. The extract was washed with water and dried over anhydrous magnesium sulfate. After separating the desiccant, the solvent was distilled off under reduced pressure. The obtained crystals are recrystallized from ethyl acetate to give a melting point of 232 to 234 ° C. 4- [3-methyl-1,6-diphenyl-4 (1H)-
0.8 g of pyridinone-2-yl] pyridine N-oxide was obtained.

Example 2 1- (2-chlorophenyl) -3-methyl-6- (2-
Methylfuran-3-yl) -2-phenyl-4 (1H)-
Synthesis of pyridinone (Compound 15) 2-Methyl-5- (2-methylfuran-3-yl)-
5.5 g of 1-phenyl-1,3,5-pentanetrione, 3.8 g of 2-chloroaniline and 5.7 g of P-toluenesulfonic acid were dissolved in 500 ml of xylene and then stirred under reflux for 5 hours. After cooling, the solvent was distilled off under reduced pressure, and the residue was extracted with chloroform. The extract was washed with 500 ml of 10% aqueous hydrochloric acid solution and 300 ml of 10% aqueous sodium hydroxide solution, further washed with water, and then dried over anhydrous magnesium sulfate. After separating the desiccant, the solvent was distilled off under reduced pressure, the residue was subjected to silica gel column chromatography, and the crystals obtained after distilling off the solvent eluted with a mixed solvent of ethyl acetate and n-hexane were recrystallized from acetone, It shows a melting point of 218 to 219 ° C. 1.1 g of 1- (2-chlorophenyl) -3-methyl-6- (2-methylfuran-3-yl) -2-phenyl-4 (1H) -pyridinone was obtained.

Example 3 3-Methyl-1,2-diphenyl-6- (pyridine-3-
Ill) -4 (1H) -pyridinone (Compound 9) N-phenyl-1-phenylpropanimine 62.8 g,
(Pyridin-3-yl) propynoic acid ethyl ester 32.2
g and aluminum chloride 40g are added to toluene 700ml, 3
The mixture was heated and stirred at 60 ° C for a day. After cooling, the reaction solution is 2N sulfuric acid
It was poured into 1000 ml and extracted with chloroform. 10% extract
The extract was washed with 400 ml of an aqueous sodium hydroxide solution and water, and then dried over anhydrous sodium sulfate. After separating the sodium sulfate, the solvent was distilled off, and the obtained residue was eluted with a mixed solvent of ethyl acetate and hexane using silica gel column chromatography. After distilling off the solvent, recrystallization from a mixed solvent of acetone and hexane gives 3-methyl-1,2-diphenyl-6 having a melting point of 224 to 226 ° C.
2.3 g of-(pyridin-3-yl) -4 (1H) -pyridinone
was gotten.

The agricultural and horticultural fungicide of the present invention comprises the compound of the present invention and may be used as the compound itself, but usually, a carrier, a surfactant, a dispersant or an auxiliary agent or the like is added by a conventional method, For example, it is used after being formulated into powder, wettable powder, emulsion, fine granule or granule.

Suitable carriers include, for example, talc, bentonite,
Examples thereof include solid carriers such as clay, kaolin, diatomaceous earth, white carbon, vermiculite, slaked lime, silica sand, ammonium sulfate and urea, and liquid carriers such as isopropyl alcohol, xylene, cyclohexanone and methylnaphthalene. Examples of the surfactant and dispersant include alcohol sulfate ester salt, alkylaryl sulfonate, lignin sulfonate, diarylmethane disulfonate,
Examples thereof include polyoxyethylene glycol ether, polyoxyethylene alkylaryl ether, and polyoxyethylene sorbitan monoalkylate. Examples of the adjuvant include carboxymethyl cellulose, polyethylene glycol, gum arabic and the like. These preparations are diluted to an appropriate concentration and then sprayed or applied directly.

The blending ratio of the active ingredient is appropriately selected as necessary, but 0.1 to 20% (weight) is suitable for powder or granules, and 5 to 80% (weight) for emulsion or wettable powder. Is.

The application rate of the agricultural and horticultural fungicide of the present invention is the type of compound used, target disease, occurrence tendency, degree of damage, environmental conditions,
Although it varies depending on the dosage form to be used, when it is used as it is as in powders and granules, it is preferably 0.1 g to 5 kg per 10 ares as an active ingredient, preferably 1 g to 1 kg. When it is finally used in a liquid state such as an emulsion or a wettable powder, 0.1 to 10,000 ppm, preferably 10
It is better to select appropriately from the range of up to 3000 ppm.

Next, examples of the agricultural and horticultural germicide of the present invention will be specifically described. % In the following examples means weight.

Example 4 (Dust) 2% of the compound (1), 5% of diatomaceous earth and 93% of clay were uniformly mixed and pulverized to obtain a dust.

Example 5 (Wettable powder) Compound (2) 50%, diatomaceous earth 45%, sodium dinaphthylmethanedisulfonate 2% and sodium ligninsulfonate 3% were uniformly mixed and pulverized to obtain a wettable powder.

Example 6 (Emulsion) Compound (3) 30%, cyclohexanone 20%, polyoxyethylene alkylaryl ether 11%, calcium alkylbenzene sulfonate 4% and methylnaphthalene
Emulsion was obtained by uniformly dissolving 35%.

Example 7 (Granule) Compound (4) 5%, sodium salt of lauryl alcohol sulfate 2%, sodium ligninsulfonate 5
%, Carboxymethylcellulose 2% and clay 86% are uniformly mixed and ground. 20 parts by weight of water was added to 80 parts by weight of this mixture, and the mixture was kneaded, processed into granules of 14 to 32 mesh using an extrusion granulator, and then dried to obtain granules.

(Effects of the Invention) The fungicide for agricultural and horticultural use of the present invention comprises rice blight, rice blast,
It has a broad antibacterial spectrum against rice and horticultural diseases such as cucumber downy mildew, cucumber gray mold, cucumber powdery mildew, and Komatsuna black soot disease, but it is particularly effective as a control agent for rice blight. This activity is prophylactically and therapeutically manifested and is persistent. Further, it has excellent characteristics such as high safety against crops, warm-blooded animals and seafood.

Next, the effect of the agricultural / horticultural germicide of the present invention will be specifically described with reference to test examples.

Test example 1 Rice crest blight prevention effect test 15 paddy rice seeds (variety: Kinnanfeng) were placed in unglazed pots with a diameter of 7 cm.
The seeds were sown one by one and grown in a greenhouse for 4-5 weeks. To the rice seedlings on which the fifth leaf was developed, 50 of the wettable powder prepared according to Example 5 was used.
It was diluted to 0 ppm with water, and 10 ml was sprayed per pot. After air-drying, cultivated in rice husk bran culture medium for 7 days.
solani) was inoculated into the strain source, placed in a humid chamber (28 ° C.), and after 5 days, the height of lesions formed in the rice leaf sheath was measured, and the control value was calculated according to the following calculation formula.

Evaluation criteria A class: Control value 90% or more B class: 〃 70 to less than 90% C class: 〃 40 to less than 70% D class: 〃 less than 40% The results are shown in Table 2 according to the above evaluation criteria.

(Compound described in JP-A-56-65871) (Compound described in JP-A No. 55-102504) Comparative agents 1 and 2 are the same as the above compounds in the following test examples.

Test Example 2 Rice blast prevention effect test 20 pieces of paddy (variety: Aichi Asahi) were sown in white porcelain pots each having a diameter of 9 cm, and grown in a greenhouse for 3 to 4 weeks. 500 ppm of the wettable powder prepared according to Example 5 was applied to the rice seedlings on which the fourth leaf had spread.
It was diluted with water and sprayed with 10 ml per pot. After air-drying, spray inoculate the spore fluid of blast fungus (Pyricularia oryzae), 25
It was placed in a humidity chamber at ℃. Five days after the inoculation, the lesions were counted and the control value was calculated from the following formula.

Evaluation criteria A class: Control value 90% or more B class: 〃 70 to less than 90% C class: 〃 40 to less than 70% D class: 〃 less than 40% The results are shown in Table 3 according to the above evaluation criteria.

Test Example 3 Cucumber downy mildew preventive effect test Twelve cucumber seeds (variety: Sagamihanjiro) were sown in 9 cm × 9 cm vinyl chloride pots and grown in a greenhouse for 7 days. A wettable powder prepared according to Example 5 was diluted with water to a cucumber seedling with cotyledon developed to 500 ppm, and 10
ml was sprinkled. After air drying, cucumber downy mildew (Pseudoperono
spora cubensis) spore suspension spray inoculation, 20-22 ℃
I put it in the wet room. 7 days after the inoculation, the number of leaves was examined according to the following criteria of disease severity to determine disease severity and control value.

Degree of disease n ⁰ : Number of leaves without disease occurrence n ¹ : Number of leaves less than 1/3 of affected area n ² : Number of leaves less than 1/3 to 2/3 n ³ : Number of leaves greater than 2/3 The results are shown in Table 4.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeharu Yaguchi 1726 Mikana, Yaizu City, Shizuoka Examiner Shoei Hoshino (56) References JP-A-56-65871 (JP, A) JP-A-55-102504 (JP, A) Synth. Commun. Vol. 13, No. 5, P.I. 411-417 (1983)

Claims (2)

(57) [Claims] 1. A general formula [In the formula, R ¹ represents a phenyl group, a pyridine-1-oxide group or a furyl group which may be substituted with a lower alkyl group,
R ² represents a phenyl group, a pyridyl group optionally substituted with a lower alkoxy group or a furyl group optionally substituted with a lower alkyl group, X represents a halogen atom or a lower alkoxy group, and n is 0 or 1, 2 Indicates an integer. However, R ¹ and R ²
Does not represent a phenyl group at the same time. ] Represented by 4
(1H) -pyridinone derivative. 2. General formula [In the formula, R ¹ represents a phenyl group, a pyridine-1-oxide group or a furyl group which may be substituted with a lower alkyl group,
R ² represents a phenyl group, a pyridyl group optionally substituted with a lower alkoxy group or a furyl group optionally substituted with a lower alkyl group, X represents a halogen atom or a lower alkoxy group, and n is 0 or 1, 2 Indicates an integer. However, R ¹ and R ²
Does not represent a phenyl group at the same time. ] Represented by 4
A fungicide for agricultural and horticultural use comprising a (1H) -pyridinone derivative as an active ingredient.