JPH0578524B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a novel agricultural and horticultural fungicide. More specifically, the present invention relates to an agricultural and horticultural fungicide that has particularly excellent fungicidal activity against rice sheath blight fungi. BACKGROUND OF THE INVENTION Among agricultural and horticultural fungicides, rice sheath blight control agents are particularly important for rice cultivation. Conventionally, organic arsenic agents have been used to control this rice sheath blight disease, but due to environmental pollution, residual toxicity, and other reasons, there has been a demand for alternative agents, and as a result, antibiotics such as polyoxin and validamycin have been used. It has been developed. However, these antibiotics have drawbacks such as being expensive, insufficiently effective, and unstable, and there is a desire for the development of a new drug for controlling rice sheath blight. By the way, in recent years, the physiological activity of 4(1H)-pyridinone derivatives has attracted attention, and research on their use as agricultural and horticultural agents has been conducted.As a result, 4(1H)- Pyridinone derivatives have been discovered (Japanese Unexamined Patent Publications No. 10250/1982 and No. 65871/1983). however,
This product has the disadvantage that it cannot effectively control rice sheath blight. Problems to be Solved by the Invention The purpose of the present invention is to find a 4(1H)-pyridinone derivative that has particularly excellent bactericidal activity against rice sheath blight fungi, and to contain this 4(1H)-pyridinone derivative as an active ingredient. The purpose of the present invention is to provide a novel agricultural and horticultural fungicide. Means for Solving the Problems In order to achieve the above object, the present inventors produced various 4(1H)-pyridinone derivatives and examined their bactericidal activity. As a result, the general formula

4(1H)-pyridinone derivatives represented by [Chemical formula] (wherein X is a halogen atom, an alkoxy group, a hydroxyl group, a nitro group, a phenyl group, or an amino group) are used as agricultural and horticultural fungicides, especially rice sheath blight. It was discovered that it is excellent as a disease control agent, and based on this knowledge, the present invention was completed. That is, the present invention provides an agricultural and horticultural fungicide characterized by containing a 4(1H)-pyridinone derivative represented by the general formula () as an active ingredient. The 4(1H)-pyridinone derivative represented by the general formula () is a known compound, and can be produced by reacting 1,5-diphenyl-1,4-pentadiin-3-one with various anilines [ "Comptes rendus" No.
Volume 224, pages 476-478 (1947), “Anare
"Annales de chimie" Volume 12,
No. 3, pp. 393-444 (1948), “Prétemps Société Chimy France (Bull.Soc.
Chim.France)” pages 734-739 (1954)].
However, the physiological activity of this compound is completely unknown so far. Specific examples of the 4(1H)-pyridinone derivatives represented by the general formula () used in the present invention are shown in Table 1. Note that the compound numbers in the table are also followed in the subsequent description.

[Table] This 4(1H)-pyridinone derivative was obtained from the above-mentioned “Pretans Société Chimy France (Bull.
Soc.Chim.France)” pages 734-739 (1954)
It can be produced according to the known method described in , or according to the method shown below. That is, 1,5-diphenylpentantrione () or its tautomer (a), (b), (c), (d) represented by the following formula

[ka] general formula

[Chemical formula] (X in the formula has the same meaning as above) By reacting with the aniline derivative represented by
- A pyridinone derivative is obtained. This reaction generally involves pentantriones of formula () or formulas (a), (b), (c),
The tautomer represented by (d) and the aniline derivative represented by the general formula () are dissolved in a suitable solvent, such as hydrocarbons such as benzene, toluene, and xylene, and halogenated carbonates such as chlorobenzene, methylene chloride, and chloroform. Hydrogen, ethers such as diisopropyl ether, tetrahydrofuran, and dioxane, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, esters such as ethyl acetate, nitriles such as acetonitrile, N,N-dimethylformamide,
It may be carried out by dissolving or suspending it in amides such as N,N-dimethylacetamide and N-methylpyrrolidone, dimethyl sulfoxide, acetic acid, etc., or it may be carried out without using a solvent, but xylene or chlorobenzene may be used. It is preferable to dissolve it in In this case, the reaction may be carried out by adding a suitable reaction aid if desired. As the reaction aid, suitable acids such as mineral acids such as sulfuric acid and hydrochloric acid, p
-Organic acids such as toluenesulfonic acid and trifluoromethanesulfonic acid; Lewis acids such as boron trifluoride, aluminum chloride, and titanium tetrachloride; and the like. Furthermore, the reaction can be allowed to proceed while the water produced by the reaction is collected using a Dean Stark trap or the like. Furthermore, depending on the reaction aid and solvent used, the reaction can be carried out in the presence of a dehydrating agent such as molecular sieves. For example, when using p-toluenesulfonic acid in dimethylsulfoxide, it is preferable to use molecular sieves 5A. The amount of molecular sieves used is usually 2 to 200 g, preferably 50 to 200 g, per 0.1 mole of 1,5-diphenylpentantrione.
selected within the range. Regarding the reaction temperature, the reaction can be carried out at any temperature from the freezing point to the boiling point of the solvent, preferably from 10° C. to the boiling point of the solvent. After the reaction is completed, the acid and molecular sieve are washed with water and an alkaline solution, or removed by means such as filtration, the reaction product is extracted with chloroform, etc., and the solvent is then removed. The desired compound is obtained. This product can be purified, if necessary, by recrystallization from acetone, methanol, ethanol, benzene, toluene, diisopropyl ether, ethyl acetate, chloroform, hexane, etc., or by silica gel column chromatography. In addition, 4(1H) represented by the above general formula ()
- As another method for producing pyridinone derivatives, 5-anilino-1,5-diphenyl-4-pentene-1,3-dione derivatives represented by the following general formula () or general formulas (a), (b), ( c), (d),
There is a method of ring-closing the tautomer represented by (e) in the presence of an acid catalyst.

(X in the formula has the same meaning as above) In this method, the 5-anilino-1,5-diphenyl-4-pentene-1,3-dione derivative represented by the general formula () or its The tautomers (a), (b), (c), (d), and (e) are dissolved in suitable solvents, such as hydrocarbons such as benzene, toluene, and xylene, and halogenated compounds such as chlorobenzene, methylene chloride, and chloroform. hydrocarbons,
diisopropyl ether, tetrahydrofuran,
It can be dissolved or suspended in ethers such as dioxane, ketones such as acetone and methyl ethyl ketone, nitriles such as acetonitrile, amides such as N,N-dimethylformamide and N,N-dimethylacetamide, and even dimethyl sulfoxide and acetic acid. The ring may be closed by using a solvent, or the ring may be closed without using a solvent. Examples of acid catalysts include polyphosphoric acid, sulfuric acid, p
-Trienesulfonic acid, aluminum chloride, etc. Regarding the reaction temperature, any temperature from the freezing point to the boiling point of the solvent, preferably 10
The reaction can be carried out at temperatures ranging from °C to the boiling point of the solvent. After the reaction is completed, ice water is added to the reaction solution, extracted with chloroform, etc., washed with water, dried, and the solvent is distilled off to obtain the desired compound. This product can be purified, if necessary, by recrystallization from benzene, toluene, methanol, chloroform, ethyl acetate, acetone, hexane, etc., or by silica gel column chromatography. The 4(1H)-pyridinone derivative represented by the general formula () thus obtained has bactericidal activity,
It has particularly excellent bactericidal activity against rice sheath blight fungi. Although the agricultural and horticultural fungicide of the present invention may be used as the compound itself, it is usually mixed with a carrier, a surfactant, a dispersant, or an auxiliary agent and prepared in a conventional manner, for example, as a powder, wettable powder, or emulsion. It is used after being formulated into fine granules or granules. Suitable carriers include, for example, solid carriers such as talc, bentonite, clay, kaolin, diatomaceous earth, white carbon, vermiculite, slaked quartz, silica sand, ammonium sulfate, urea, and liquid carriers such as isopropyl alcohol, xylene, cyclohexanone. Examples include. Examples of surfactants and dispersants include alcohol sulfate salts, alkyl sulfonate salts, lignin sulfonate salts, polyoxyethylene glycol ethers, polyoxyethylene alkylaryl ethers, and polyoxyethylene sorbitan monoalkylates. Examples of the adjuvant include carboxymethyl cellulose, polyethylene glycol, and gum arabic. These preparations can be diluted to an appropriate concentration and sprayed, or applied directly. The blending ratio of the active ingredient is selected as necessary, but when making powder or granules, it should be 0.5~
20% by weight, and in the case of emulsions or wettable powders, a range of 5 to 80% by weight is suitable. The application amount of the agricultural and horticultural fungicide of the present invention varies depending on the type of compound used, the target disease, the tendency of occurrence, the degree of damage, environmental conditions, the dosage form used, etc. When used as is, it is best to select an appropriate amount of the active ingredient from the range of 10 to 500 g per 10 ares, and when used in a final liquid form such as an emulsion or wettable powder, the amount of active ingredient should be appropriately selected from the range of 10 to 500 g per 10 ares.
It is best to select an appropriate amount from the range of 1000ppm. Effects of the Invention The agricultural and horticultural fungicide of the present invention has a wide antibacterial spectrum against rice and horticultural diseases such as rice sheath blight, rice blast, downy mildew, downy mildew, and Japanese mustard rot. However, it is particularly effective as a control agent for rice sheath blight. This activity is expressed both prophylactically and therapeutically, and is persistent. Furthermore, it has excellent characteristics such as being highly safe for crops, warm-blooded animals, and fish and shellfish. Examples Next, the present invention will be explained in more detail with reference to Examples. In addition, % in an example means weight. Production Example 1 - Production of (2-chlorophenyl)-2,6-diphenyl-4(1H)-pyridinone (compound 1) 1,5-diphenyl-1,3,5-pentantrione 11.2 g (0.042 mol), 2 -chloroaniline
42.6g (0.33mol), p-toluenesulfonic acid 6.0
g (0.032 mol) and molecular sieves
45.0 g of 5A was added to 300 ml of xylene and refluxed for 3 hours. After cooling, remove the solids and add 10% hydrochloric acid to the organic layer.
100ml followed by 100ml of 10% aqueous sodium hydroxide solution
After washing with water, the mixture was further washed with water, dried over anhydrous magnesium sulfate, and then the solvent was distilled off. next,
The obtained residue was crystallized from a mixed solvent of acetone/hexane (1/1) to give 1-
(2-chlorophenyl)-2,6-diphenyl-4
4.5 g of (1H)-pyridinone was obtained. Example 1 (Powder) 2% compound (1), 5% diatomaceous earth, and 93% clay were uniformly mixed and pulverized to obtain a powder. Example 2 (Wettable powder) 50% of compound (2), 45% of diatomaceous earth, 2% of sodium dinaphthylmethane disulfonate and 3% of sodium ligninsulfonate were uniformly mixed and pulverized to prepare a wettable powder. Example 3 (Emulsion) An emulsion was prepared by uniformly dissolving 30% of compound (3), 20% of cyclohexanone, 11% of polyoxyethylene alkylaryl ether, 4% of calcium alkylbenzene sulfonate, and 35% of methylnaphthalene. Example 4 (Granules) 5% of compound (4), 2% of sodium salt of lauryl alcohol sulfate, 5% of sodium lignin sulfonate, 2% of carboxymethylcellulose and 86% of clay are uniformly mixed and ground. Add 20% water to this mixture, knead it, and use an extrusion granulator.
After processing into 14 to 32 mesh granules, they were dried and made into granules. Test example Rice sheath blight prevention effect test Rice seeds in a clay pot with a diameter of 7 cm (variety: Kinnanpu)
15 seeds each were sown and grown in a greenhouse for 4 to 5 weeks. A hydrating powder prepared according to Example 2 was diluted with water to a predetermined concentration and sprayed at 10 ml per pot to rice seedlings in which the fifth leaf had developed. Rhizoctonia solani cultured for 7 days on rice grass medium after air drying
was inoculated at the base of the plant, placed in a greenhouse (28°C), and after 5 days, the length of the lesion formed on the rice leaf sheath was measured.
The control value was calculated according to the following criteria. Control value (%) = (1 - lesion length in treated area/lesion length in untreated area) x 100 The results are shown in Table 2.

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Claims (1)

[Claims] 1. A 4(1H)-pyridinone derivative represented by the general formula [Formula] (wherein X is a halogen atom, an alkoxy group, a hydroxyl group, a nitro group, a phenyl group, or an amino group) An agricultural and horticultural fungicide characterized by containing it as an ingredient.