JP2003026516A - Agricultural/horticultural fungicide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an agricultural/horticultural fungicide comprising as the active ingredient a thiadiazole derivative. SOLUTION: This agricultural/horticultural fungicide comprises as the active ingredient a thiadiazole compound of the general formula (I) (where, R<1> and R<2> are each H, a halogen atom, lower haloalkyl, lower alkoxycarbonyl or cyano; R<3> is H or a halogen atom; R<4> is a lower alkyl; and X is an oxygen atom or sulfur atom).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an agricultural and horticultural fungicide containing a thiadiazole derivative as an active ingredient.

[0002]

2. Description of the Related Art Conventionally, in the field of agriculture and horticulture, various fungicides for controlling various diseases have been developed and put into practical use. However, conventionally used agricultural and horticultural germicides are not always satisfactory in terms of germicidal effect, germicidal spectrum or residual effect. Another problem is the emergence of pathogenic bacteria that have acquired resistance to conventional general-purpose pesticides. For example, in the cultivation of vegetables, fruit trees, flowers, tea, barley and rice, etc., various strains of fungicides, such as triazoles, imidazoles, pyrimidines, benzimidazoles, dicarboximides, phenylamides, methoxy. Various pathogens that have acquired resistance to acrylate fungicides have appeared in various places, and it is becoming difficult to control various diseases caused by these existing agent-resistant pathogens every year. On the other hand, some pesticides such as dithiocarbamates and phthalimide pesticides have not yet acquired resistance to pathogenic bacteria, but they cannot be said to have sufficient bactericidal effect.
In addition, these are generally used many times and are not preferable from the viewpoint of environmental pollution.

Therefore, the development of a new fungicide that shows a sufficient control effect with a low dose even against various pathogenic bacteria that have acquired resistance to conventional general-purpose agricultural and horticultural fungicides, and has little adverse effect on the environment. Coveted. Further, regarding the thiadiazole compound of the present invention, for example, JP-B-7-11618
Although it is reported in JP-A No. 3 as having insecticidal / miticidal activity, no bactericidal activity is described at all.

[0004]

The present invention has a high control effect against various pathogenic bacteria which are resistant to conventional agricultural and horticultural fungicides, and is highly safe with reduced problems such as environmental pollution. , To provide a chemical substance useful as an active ingredient of an agricultural / horticultural germicide.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to solve the above problems, and as a result, the above-mentioned specific thiadiazole compound having insecticidal and acaricidal activity has high bactericidal activity. Furthermore, they have found that those having an R-configuration in the absolute configuration of the asymmetric carbon have higher bactericidal activity and a broader bactericidal spectrum, and have completed the present invention.

That is, the gist of the present invention is the following general formula (I):

[0007]

[Chemical 4]

[In the formula, R ¹ and R ² are the same or different and each represents a hydrogen atom, a halogen atom, a lower haloalkyl group,
A lower alkoxycarbonyl group or a cyano group is shown. R
³ represents a hydrogen atom or a halogen atom, R ⁴ represents a lower alkyl group, and X represents an oxygen atom or a sulfur atom. ]
A thiadiazole compound represented by the following formula exists in an agricultural and horticultural fungicide containing the following formula (I
I)

[0009]

[Chemical 5]

The present invention lies in an optically active thiadiazole compound having an absolute configuration of R configuration and a production intermediate thereof. Hereinafter, embodiments of the present invention will be described in detail.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The fungicide of the present invention has the general formula (I)
The compound represented by is an active ingredient. In the general formula (I), R ¹ and R ² are the same or different,
Hydrogen atom; halogen atom such as fluorine atom, chlorine atom or bromine atom; fluoromethyl group, difluoromethyl group,
C _{1 to} C ₄ such as trifluoromethyl group and fluoroethyl group
Haloalkyl group; a methoxycarbonyl group, e butoxycarbonyl group, C ₂ -C ₅ alkoxycarbonyl groups such as propoxycarbonyl group; indicates or cyano group, of which preferably a hydrogen atom, a halogen atom, C ₁ -C ₂ Is a haloalkyl group, a methoxycarbonyl group or a cyano group, and particularly preferably a hydrogen atom, a halogen atom, a trifluoromethyl group or a cyano group. R ³ represents a hydrogen atom; or a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom, and of these, a hydrogen atom is preferable.
R ⁴ represents an alkyl group of C ₁ -C _4, preferably C ₁ ~
It is a C ₂ alkyl group, particularly preferably an ethyl group.

X represents an oxygen atom or a sulfur atom, of which the oxygen atom is preferable. Among the above-mentioned substituents, preferable combinations include those in which the above-mentioned substituents are preferable, and as the combination of R ¹ and R ^2, a combination of a hydrogen atom and a haloalkyl group is preferable. The compound represented by the above general formula (I) has one asymmetric carbon atom, but a compound whose absolute configuration is R configuration is more preferable in view of its activity and broad spectrum of sterilization, and the most preferable one is , Formula (II)

[0013]

[Chemical 6]

Examples include compounds represented by: The compound represented by the above formula (II) is a novel compound. The compound represented by the general formula (I) can be produced by the methods described in Japanese Patent Publication No. 7-116183 and Japanese Patent Registration No. 2504438, and methods analogous thereto.

Among the compounds represented by the general formula (I), an optically active thiazole compound having an absolute configuration of R configuration is
It can be obtained by resolving a racemic thiazole compound represented by the general formula (I) by column chromatography using an optically active packing material. In addition, a novel intermediate formula (IV)

[0016]

[Chemical 7]

[In the formula, R ¹ , R ² , R ³ , R ⁴ and X have the same meanings as described above. ] It can manufacture also by carrying out cyclization condensation of the optically active hydrazine derivative represented by these in the presence of a dehydrating agent. The compound represented by the above general formula (III) is a useful intermediate in the production of the compound represented by the formula (II), which is the most preferable compound in the present invention.

Examples of the dehydrating agent used here are concentrated sulfuric acid, phosphorus pentoxide, phosphorus pentasulfide, polyphosphoric acid, acetic anhydride,
Examples thereof include methanesulfonic acid, and concentrated sulfuric acid is particularly preferable. This reaction is usually performed without a solvent, but in some cases, aromatic hydrocarbons such as benzene, toluene, xylene,
It can also be carried out in an inert solvent such as halogenated hydrocarbons such as methylene chloride, chloroform, 1,1,2,2-tetrachloroethane or ethers such as ether, tetrahydrofuran and dioxane. The reaction temperature varies depending on the type of dehydrating agent, but is usually about -10 to 200 ° C.

The optically active hydrazine derivative represented by the above general formula (IV) can be produced by the following production method. (Production method 1) The following general formula (V)

[0020]

[Chemical 8]

[In the formula, R ¹ , R ² , R ³ , R ⁴ and X are as defined above. ] The optically active propionic acid derivative represented by the following general formula (VI)

[0022]

[Chemical 9]

[In the formula, R ⁴ has the same meaning as described above. ] It manufactures by making it react with the thiocarbazic acid derivative represented by these in the presence of a base. It is preferable to use sodium methoxide or sodium ethoxide as the base. The reaction is usually carried out in a solvent, and as the solvent, aromatic hydrocarbons such as benzene, toluene and xylene, amides such as formamide and N, N-dimethylformamide or ethers, ethers such as tetrahydrofuran and dioxane, methanol, Examples thereof include alcohols such as ethanol and the like, or a mixture thereof.

The amount of the reagent used in the reaction is determined by the general formula (V).
1-3 mol, preferably 1 mol of the thiocarbazic acid derivative represented by the general formula (VI) per 1 mol of the compound represented by
~ 1.5 mol, sodium methoxide or sodium ethoxide is 1 to 3 mol, preferably 1 to 2 mol. The reaction temperature is generally -20 to 100 ° C, preferably 0 to
40 ° C. (Production method 2) The following general formula (VII)

[0025]

[Chemical 10]

[In the formula, R ¹ , R ² , R ³ and X are as defined above. ] The optically active phenoxypropionyl chloride derivative represented by the following general formula (V
It is produced by reacting the thiocarbazic acid derivative represented by I) in the presence of a base. Examples of the base used in this reaction include inorganic bases such as sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate and sodium hydride, triethylamine, pyridine, N, N-
Examples include organic bases such as dimethylaniline.

The reaction is usually carried out in a solvent, and the solvent is an aromatic hydrocarbon such as benzene, toluene or xylene,
Ketones such as acetone and methyl ethyl ketone, esters such as ethyl formate and ethyl acetate, nitriles such as acetonitrile and propionitrile, formamide, N, N-
Examples thereof include amides such as dimethylformamide, inert solvents such as ethers, ethers such as tetrahydrofuran and dioxane, and mixtures thereof.

The amount of the reagent used in the reaction is determined by the general formula (VII
1 mol of the compound represented by I), the thiocarbazic acid derivative represented by the general formula (VI) is 1 to 3 mol, preferably 1 to 1.5 mol, and the base is 1 to 3 mol, preferably 1 to
2 mol. The reaction temperature is generally -20 to 100 ° C, preferably 0 to 40 ° C. (Production method 3) The following general formula (VI
II)

[0029]

[Chemical 11]

[In the formula, R ¹ , R ² , R ³ and X are as defined above. ] The optically active phenoxypropionic acid derivative represented by the above and the thiocarbazic acid derivative represented by the general formula (VI) similar to the above Production method 1 are reacted in the presence of a dehydration condensation agent. As the dehydration condensation agent,
Examples thereof include dicyclohexylcarbodiimide, diisopropylcarbodiimide, N-ethyl-N′-3-dimethylaminopropylcarbodiimide, diphenylphosphoryl azide and the like.

The reaction is usually carried out in a solvent, and the solvent is an aromatic hydrocarbon such as benzene, toluene or xylene,
Examples thereof include halogenated hydrocarbons such as methylene chloride, chloroform, 1,1,2,2-tetrachloroethane and the like, inert solvents such as ethers, ethers such as tetrahydrofuran and dioxane, and mixtures thereof. The amount of the reagent used in the reaction is 1 to 3 mol, preferably 1 to 1.5 mol, of the thiocarbazic acid derivative represented by the general formula (VI), relative to 1 mol of the compound represented by the general formula (VIII). The dehydration condensing agent is 1 to 3 mol, preferably 1 to 2 mol. The reaction temperature varies depending on the type of dehydrating agent, but is usually -1.
It is about 0 to 200 ° C.

The starting materials represented by the general formulas (V), (VII) and (VIII) used in the above Production Method 1 to Production Method 3 can be obtained, for example, by the following reaction.

[0033]

[Chemical 12]

[In the formula, R ¹ , R ² , R ³ , R ⁴ and X have the same meanings as described above, and Z represents a halogen atom, an alkylsulfonyloxy group or an arylsulfonyloxy group. Further, the optically active hydrazine derivative represented by the general formula (IV) is not only not only chemically pure but also surprisingly recrystallized upon isolation after being produced by the above Production Method 1 to Production Method 3. Especially, the optical purity can be increased. In this case, unlike the usual case, it is considered that the enantiomer preferentially precipitates rather than the racemate.

Examples of the recrystallization solvent include aromatic hydrocarbons such as benzene, toluene and xylene, aliphatic hydrocarbons such as hexane, heptane and octane, methylene chloride, chloroform and 1,1,2,2-tetrachloroethane. And halogenated hydrocarbons such as ethers, ethers such as tetrahydrofuran and dioxane, alcohols such as methanol and ethanol, inert solvents such as esters such as ethyl formate and ethyl acetate, or a mixture thereof. Of these, a combination of an aromatic hydrocarbon solvent, a halogenated hydrocarbon solvent and a solvent selected from an ester solvent and an aliphatic hydrocarbon solvent is preferable, and a solvent selected from toluene, chloroform and ethyl acetate and hexane or A combination with heptane is particularly preferred.

The compound represented by the above general formula (I) has a high bactericidal activity against various plant pathogenic fungi such as powdery mildew, pathogen and downy mildew, and is an active ingredient of agricultural and horticultural fungicides. Is useful as However, the phytopathogenic fungi to be controlled by the compound of the present invention are not limited to those exemplified above. When the compound of the present invention is used as a fungicide for agricultural and horticultural use, it may be used alone, but it is preferably used as a composition to which an agricultural chemical auxiliary widely used in the art is added. The dosage form of the agricultural and horticultural fungicide is not particularly limited, but it is preferable to take a form such as an emulsion, a wettable powder, a wettable granule, a water solution, a liquid, a flowable agent, a powder, and a granule. One kind or two or more kinds of the above compounds can be blended as an active ingredient.

Agricultural and horticultural fungicides used for producing agricultural and horticultural fungicides are, for example, substances having effects such as improvement of the effects of agricultural and horticultural fungicides, stabilization, and improvement of dispersibility.
Carriers (diluents), spreading agents, emulsifiers, wetting agents, dispersants, disintegrating agents and the like can be used. The carrier that can be used in the disinfectant composition of the present invention may be either solid or liquid as long as it is commonly used for agricultural and horticultural agents, and is not limited to a particular one. In addition to these, various auxiliaries, and if necessary, stabilizers such as antioxidants and ultraviolet absorbers, and coloring agents can be used. Effective content (%) of the active ingredient of the present invention in these preparations
Is selected from the range of 0.1 to 99.5%,
It may be appropriately determined according to various conditions such as application method. For example, in the case of emulsions, wettable powders, wettable powders, water solutions, liquids, and flowables, the range is 1 to 90% (weight%: the same hereinafter), and in the case of powders and granules, 0.5 to 10%. Can be in the range of.

The agricultural and horticultural fungicides of the present invention include other fungicides, insecticides, acaricides, herbicides, insect growth regulators and fertilizers as long as they do not impair the activity of the compound of the present invention as an active ingredient. Any active ingredient such as a soil conditioner may be blended.
The application method of the agricultural or horticultural fungicide of the present invention is not particularly limited, and it can be applied by any method such as foliage spraying, water surface application, soil treatment, and purpose treatment.

[0039]

EXAMPLES The present invention will be described in more detail with reference to Production Examples, Formulation Examples and Test Examples of the compounds of the present invention, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded. Production Example 1 According to Japanese Examined Patent Publication No. 7-116183 Production Example 1 and Production Example 2, 18 compounds listed in Table 1 were obtained.

[0040]

[Table 1]

Production Example 2 Compound Nos. Listed in Table 1 6 (2-ethoxy-5- [1
-[4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] ethyl] -1,3,4-thiadiazole) was subjected to optically active column chromatography (filler: CHIRALPAK AS (manufactured by Daicel Chemical Industries, Ltd.),
(R) -2-ethoxy-5 represented by the formula (II) by optical resolution with a developing solvent: hexane / isopropanol).
[1- [4- (5-trifluoromethylpyridine-2-
Iloxy) phenoxy] ethyl] -1,3,4-thiadiazole (Compound No. 19) was obtained. Purity 99.5
% Or more (by liquid chromatography. 254n
m). Optical purity 99.5% ee or higher (by optically active column liquid chromatography). Melting point 69.8-70.
8 ° C.

At the same time, it is an enantiomer (S) -2-
Ethoxy-5- [1- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] ethyl]-
1,3,4-thiadiazole (Compound No. 20) was also obtained. Production Example 3-1 Ethyl (S) -2- (4-methylphenylsulfonyloxy) propionate 500 ml In a flask, (S) -ethyl lactate 26.0
g, p-toluenesulfonic acid chloride 38.1 g and toluene 120 ml were charged, and triethylamine 24.3 g was added dropwise thereto. Since a little heat was generated in the initial stage of the reaction, the reaction mixture was water-cooled to keep the reaction temperature at 25 to 30 ° C. The reaction was carried out as it was by stirring at room temperature for 72 hours. Water was poured, the precipitate was dissolved, and the layers were separated. The organic phase was washed with dilute hydrochloric acid, water (twice) and saturated brine in this order. Concentrated under reduced pressure to give 51.7 g of ethyl
(S) -2- (4-methylphenylsulfonyloxy)
I got a propionate. Yield 95.0%. Purity 97.8
% (By gas chromatography).

Production Example 3-2 Ethyl (R) -2- [4
4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionate In a 2000 ml flask, 4- (5-trifluoromethylpyridin-2-yloxy) phenol 47.4
g, potassium carbonate 30.8 g, ethyl (S) -2-
51.7 g of (4-methylphenylsulfonyloxy) propionate and 465 ml of acetonitrile were charged, and the reaction was carried out for 10 hours while heating under reflux on an oil bath at 95 ° C. After cooling, the precipitate was filtered and washed, and the mother liquor washings were combined and concentrated under reduced pressure. The residue was dissolved in 500 ml of ethyl acetate and washed with 200 ml of water and 200 ml of saturated saline (x2) in this order. Concentrate under reduced pressure to give 66.0 g of ethyl (R) -2-
[4- (5-Trifluoromethylpyridin-2-yloxy) phenoxy] propionate was obtained. Yield 100
%. Purity 95.0% (by gas chromatography). Optical purity 84.1% ee (by optically active liquid chromatography).

Production Example 3-3 (R) -3- [2- [4-
(5-trifluoromethylpyridin-2-yloxy)
Phenoxy] propionyl] -thiocarbazic acid-O-
(R) -2- [4- (5-
Trifluoromethylpyridin-2-yloxy) phenoxy] propionate 66.0 g, thiocarbazic acid-O-ethyl ester of the formula (VI) 24.6 g and toluene 372 ml were charged, and 30% sodium methoxide methanol solution 50 was added. 0.2g was dripped in 5 minutes. After the dropping, the reaction was carried out as it was with stirring at room temperature for 2.5 hours. The mixture was neutralized with diluted hydrochloric acid prepared by mixing 30 ml of concentrated hydrochloric acid and 70 ml of water. 200 ml of ethyl acetate was added, and after stirring well, the layers were separated. The oil phase was washed with water and saturated brine in this order, concentrated under reduced pressure, and recrystallized from a hexane / ethyl acetate mixed solvent to give 65.1 g of (R) -3-.
[2- [4- (5-trifluoromethylpyridine-2-
Iloxy) phenoxy] propionyl] -thiocarbazic acid-O-ethyl ester was obtained. Yield 82%. Purity 99.4% (by liquid chromatography. 254n
m). Optical purity 85.2% ee (by optically active liquid chromatography).

Production Example 3-4 (R) -2-ethoxy-5
-[1- [4- (5-trifluoromethylpyridine-2
-Yloxy) phenoxy] ethyl] -1,3,4-thiadiazole 1000 ml flask was charged with 260 g of concentrated sulfuric acid,
While maintaining the reaction temperature at 5 to 10 ° C. under ice cooling, 65.1 g of (R) -3- [2- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionyl]
-Thiocarbazic acid-O-ethyl ester was added in small portions. The reaction was completed by stirring for 3 hours as it was. The reaction solution was poured onto crushed ice, and the precipitate was dissolved in 500 ml of ethyl acetate.
It was extracted with. The aqueous phase was extracted with 200 ml of ethyl acetate, and the oil phases were combined and washed with saturated saline. After concentration under reduced pressure, the residue was crystallized, pulverized and dried under reduced pressure to obtain 58.1 g of the formula (II
(R) -2-ethoxy-5- [1- [4
-(5-Trifluoromethylpyridin-2-yloxy) phenoxy] ethyl] -1,3,4-thiadiazole was obtained. Yield 93%. Melting point 67.1-68.5 [deg.] C. Purity 99.9% (by liquid chromatography. 25
4 nm). Optical purity 85.2% ee (by optically active liquid chromatography).

Production Example 4-1 (R) -2- [4- (5-
Trifluoromethylpyridin-2-yloxy) phenoxy] propionic acid Ethyl (R) -2-obtained in the same manner as in Production Example 3-2.
100 mg of 24.9 g of [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionate
Dissolve in ml of ethanol and add caustic soda 4.2
A solution of 20 g of water in 20 ml was added. The reaction was completed by stirring at room temperature for 4 hours. About half amount of ethanol was distilled off under reduced pressure at a temperature of 40 ° C. or lower. After dissolving in water, it was extracted with ethyl acetate. The aqueous layer was acidified with concentrated hydrochloric acid, and the precipitate was extracted with ethyl acetate. After washing with water and saturated saline, concentrate under reduced pressure to 2
2.1 g of (R) -2- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionic acid were obtained. Yield 96.5%. Purity 98.6% (by liquid chromatography, 254 nm).

Production Example 4-2 (R) -3- [2- [4-
(5-trifluoromethylpyridin-2-yloxy)
Phenoxy] propionyl] -thiocarbazic acid-O-
(R) -2- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionic acid (16.4 g), toluene (100 ml) and thionyl chloride (7.2 ml) were placed in a 300 ml ethyl ester flask and placed on an oil bath. The reaction was carried out by heating under reflux for 3 hours. Concentrated under reduced pressure to give crude (R) -2
-[4- (5-Trifluoromethylpyridin-2-yloxy) phenoxy] propionic acid chloride was obtained. This was directly used for the next reaction.

In a 300 ml flask, 7.2 g of thiocarbazic acid-O-ethyl ester, 1 of triethylamine were added.
Charge 0.1 g and 100 ml of toluene, and keep the reaction temperature on an ice-methanol bath at -10 to -5 ° C.
(R) -2- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionic acid chloride was added dropwise. After the dropping, the bath was removed and the reaction was carried out by stirring at room temperature for 3 hours.

The reaction solution was washed with water, diluted hydrochloric acid, water and saturated saline in this order. Concentrate under reduced pressure and dry to 20.7 g of crude (R) -3- [2- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] propionyl].
-Thiocarbazic acid-O-ethyl ester was obtained. Crude yield 96.4%. Purity 86.2% (by liquid chromatography, 254 nm). Optical purity 73.4% ee (by optically active liquid chromatography). This was repeatedly recrystallized three times from a mixed solvent of ethyl acetate / hexane 1
3.1 g of purified product was obtained. Yield 61.0%. Purity 99.
9%. Optical purity 95.9% ee. Melting point 132.7-1
33.5 ° C.

Production Example 4-3 (R) -2-Ethoxy-5
-[1- [4- (5-trifluoromethylpyridine-2
-Yloxy) phenoxy] ethyl] -1,3,4-thiadiazole In the same manner as in Production Example 3-4, (R) -3- [2- [4-
(5-trifluoromethylpyridin-2-yloxy)
Phenoxy] propionyl] -thiocarbazic acid-O-
Purified product of ethyl ester 8.6 g to 7.6 g of (R)
2-Ethoxy-5- [1- [4- (5-trifluoromethylpyridin-2-yloxy) phenoxy] ethyl] -1,3,4-thiadiazole was obtained. Yield 92.
4%. Melting point 68.1-69.9 [deg.] C. Purity 99.9% (by liquid chromatography, 254 nm). Optical purity 96.0% ee (by optically active liquid chromatography).

Next, formulation examples of the compound of the present invention will be shown. In addition,
Hereinafter, "part" and "%" mean "part by weight" and "% by weight", respectively. Formulation Example 1 Emulsion 20 parts by weight of the compound of the present invention, Solpol 3005X (mixture of nonionic surfactant and anionic surfactant,
15 parts by weight of Toho Chemical Industry Co., Ltd., xylene 3
It was dissolved in a mixed solvent consisting of 5 parts by weight and 30 parts by weight of methylacetamide to obtain an emulsion containing 20% by weight of the active ingredient.

Formulation Example 2 Wettable powder 20 parts by weight of a compound of the present invention, Carplex # 80D
(White carbon, Shionogi Pharmaceutical Co., Ltd., trade name) 20
5 parts by weight, ST Kaolin clay (Kaolinite, Tsuchiya Kaolin Industry Co., Ltd., trade name) 5 parts by weight, Lunox P65
3 parts by weight of L (anionic surfactant, trade name of Toho Chemical Industry Co., Ltd.) was mixed and uniformly pulverized to obtain a wettable powder containing 20% by weight of the active ingredient.

Formulation Example 3 Granule wettable powder 40 parts by weight of the compound of the present invention, ST kaolin clay (kaolinite, Tsuchiya Kaolin Industry Co., Ltd., trade name) 52 parts by weight, Solpol 9047K (anionic surfactant, Toho Kagaku Co., Ltd.) Kogyo Co., Ltd., 5 parts by weight, Lunox P6
After mixing 3 parts by weight of 5 L (anionic surfactant, Toho Chemical Industry Co., Ltd., trade name) and crushing, kneading, extruding, granulating (diameter 0.8 mm), drying and sizing 40% by weight To obtain a wettable granule.

Formulation Example 4 Flowable agent 20 parts by weight of the compound of the present invention, Solpol 9047K
5 parts by weight, sorbon T-20 (nonionic surfactant,
Toho Chemical Industry Co., Ltd., 3 parts by weight, 8 parts by weight of ethylene glycol and 54 parts by weight of water were wet-milled, and 10 parts by weight of a 1% by weight xanthan gum (natural polymer) aqueous solution was added to the slurry mixture. Mix well and active ingredient 2
A flowable amount of 0% by weight was obtained.

Test Example 1 Control Effect Test for Tomato Powdery Mildew Five tomato plants (cultivar: red cherry) were grown per pot in a resin pot having a diameter of 9 cm. The agricultural and horticultural fungicide (emulsion) of the present invention prepared according to the formulation of Preparation Example 1 was diluted with water to a predetermined concentration and sprayed on the above tomatoes (3 to 4 leaf stage) at a rate of 10 ml per pot. After air-drying the sprayed chemical solution, tomatoes were exposed and inoculated with spores obtained from tomato leaves infected with Tomato powdery mildew ( Olpidium Violae ), and then left in a greenhouse (25 ° C.) for 7 to 10 days. For evaluation, the diseased area ratio of each leaf was evaluated and the control value (%) was calculated by the following formula. The results are shown in Table 2.
Shown in.

[0056]

[Equation 1]

[0057]

[Table 2]

From the above, it can be seen that all the compounds of the present invention exhibit an excellent bactericidal effect. Test Example 2 Control effect test against tomato epidemic disease In a resin pot having a diameter of 6 cm, 3 tomatoes (variety: red cherry) were grown per pot. The agricultural and horticultural fungicide (emulsion) of the present invention prepared according to the formulation of Preparation Example 1 was diluted with water to a predetermined concentration and sprayed on the above tomatoes (3 to 4 leaf stage) at a rate of 10 ml per pot. After air-drying the sprayed chemical solution, the tomato after culturing on tomato cut leaves ( Phytophthora infe)
spores of zoosporangium suspension (5.0 × 10 ⁴ zoosporangium / ml) was spray-inoculated and kept in a humid chamber at 25 ° C. for 24 hours. Then, leave it in the greenhouse (20-22 ° C) for 4 days,
The number of lesions appearing in the leaves was measured and shown by the disease index, and the control value was calculated by the following formula. The results are shown in Table 3.

[0059]

[Equation 2]

[0060]

[Table 3]

From the above, it is understood that among the compounds of the present invention, those having an asymmetric carbon absolute configuration of R configuration have a wider spectrum and exhibit a stable and high effect.

[0062]

INDUSTRIAL APPLICABILITY According to the present invention, there is provided an agricultural / horticultural fungicide having a fungicidal activity against various pathogenic bacteria.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 4C055 AA01 BA01 BA42 CA01 CA13                       CB02 DA01 FA32                 4C063 AA01 BB08 CC62 DD12 EE03                 4H011 AA01 BA01 BB10 BC01 BC03                       BC06 BC18 BC19 BC20 DA02                       DA15 DA16 DC01 DC04 DC05                       DH10 DH14

Claims (6)

[Claims] 1. The following general formula (I): [In the formula, R ¹ and R ² are the same or different and each represents a hydrogen atom, a halogen atom, a lower haloalkyl group, a lower alkoxycarbonyl group or a cyano group. R ³ represents a hydrogen atom or a halogen atom, R ⁴ represents a lower alkyl group, and X represents an oxygen atom or a sulfur atom. ] An agricultural and horticultural fungicide containing a thiadiazole compound represented by the following as an active ingredient. 2. The fungicide for agricultural and horticultural use according to claim 1, wherein R ¹ and R ² are a combination of a hydrogen atom and a haloalkyl group, and R ³ is a hydrogen atom. 3. The agricultural / horticultural fungicide according to claim 1, wherein X is an oxygen atom. 4. The fungicide for agricultural and horticultural use according to claim 1, which comprises an optically active thiadiazole compound in which the absolute configuration of the asymmetric carbon is R configuration as an active ingredient. 5. The following general formula (II): An optically active thiadiazole compound represented by: 6. A compound represented by the following general formula (III): [In the formula, R ⁴ represents a lower alkyl group. ] The optically active hydrazine compound shown by these.