JPH04978B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a cyanodithioacetate derivative having the following general formula and an agricultural and horticultural fungicide containing the compound as an active ingredient. general formula (In the formula, R ₁ is a hydrogen or chlorine atom, R ₂ is an alkyl group (which may include an oxo group), a benzyl group, an alkylcarbamoyl group (which may include a cyclized alkyl group), an alkyl group, an alkoxycarbonyl group or diethoxythiophosphoryl group.) Representative examples of the compounds represented by the above general formula are shown in Table 1. The compounds are represented by the substituents of R ₁ and R ₂ in the above general formula. In addition, NMR in the physical properties column indicates nuclear magnetic resonance spectra, and solvents are indicated in parentheses, and the display method follows the conventional method. IR is an infrared absorption spectrum, the measurement method is shown in parentheses, and only the wave number of the main peak is shown.

[Table] To obtain the compounds of the present invention, for example, methyl-
A reaction reagent corresponding to the target compound such as 2-(substituted phenyl)-2-cyanodithioacetate and isocyanate, acid chloride, chloroformate, carbamoyl chloride, diethylthiolyl acid chloride, etc., for example, ethanol, tetrahydrofuran, Synthesis in an appropriate solvent such as benzene, if necessary, in the presence of an appropriate base such as triethylamine, sodium alcoholate, potassium carbonate, etc., at room temperature or under heating for 1 hour to several days. can do. Typical synthesis examples will be shown below and explained in more detail. Synthesis Example Synthesis of S-(parachloro-2-cyano-1-methylthio)styryl(N-methyl)thiocarbamate. Dissolve 3.6 g of methyl 2-(parachlorophenyl)-2-cyanodithioacetate in cyclohexane and benzene, add 1.0 g of methyl isocyanate and 3 drops of triethylamine, and let stand at room temperature for 4 days. The solvent was decanted, and the precipitated crystals were collected and washed with benzene to obtain 3 g of transparent crystals of the desired product. The compounds of the present invention are effective in controlling a wide range of diseases of agricultural and horticultural crops, and the main ones include the following. Paddy rice blast, sesame leaf blight; beans brown spot;
Fruit trees apple black star, monilia disease, powdery mildew;
Citrus black spot, scab; pear red star, scab;
Peach: curly leaves, black star, gray mold; brown: anthracnose, mochi, net blast; persimmon: anthracnose, defoliation, powdery mildew; vegetables: yellow cucumber, downy mildew, carbon, black star, gray mold, powdery mildew, vine wart ; Tomato blight, leaf mold, gray mold; Radish chlorosis; Beet brown spot;
Late blight; melon anthracnose, vine blight, etc. There is not necessarily a limit on the amount of spraying, but when spraying on fields where crops are usually grown, the amount of active ingredient compound (AI) is 50 to 1000g/10a.
When applied in a soil pot, approximately 2 to 8 Kg A.I./10a is appropriate. Of course, this is just a guideline, and it may be adjusted as necessary, taking into account factors such as the type of crop, the type and degree of damage, the season, the weather, and the dosage form of the drug. As mentioned above, the compound of the present invention can be used as a fungicide for agricultural and horticultural purposes, and can be used as it is or mixed with a carrier (diluent) to form powders, granules, wettable powders, emulsions, oils, and other suitable agrochemical preparations. It is used as an agent. In this case, a spreading agent, an emulsifier, a wetting agent, a fixing agent, etc. are used as necessary, and it can also be used in combination or mixed with other fungicides, insecticides, herbicides, fertilizers, etc. Example 1 Powder Compounds listed in the table as active ingredients 3 parts Clay 40 parts Talc 57 parts Example 2 Wettable powder Compounds listed in the table 75 parts Polyoxyethylene alkyl allyl ether
9 parts White carbon 16 parts In order to specifically explain the effects of the compound of the present invention, typical test examples will be shown below. However, these are merely examples, and it goes without saying that the application examples of the present invention are not limited to these. Test Example 1 Rice Blast Efficacy Test <Method> Spray an amount equivalent to 200/10a of a chemical solution with a prescribed concentration on the 3-leaf stage of potted rice (variety: Jukoku).
Rice blast fungus (Pyricularia
oryzae) conidia per field of view at 100x magnification.
The suspension was prepared by spray inoculation. Immediately after inoculation, keep it in the dark for 48 hours at a temperature of 23℃ and 100% humidity, then leave it in a greenhouse for 10 minutes.
Days later, the degree of disease onset was examined using the following criteria, and the disease severity was calculated. However, the number of runs shall be three. Disease severity = Σnf / Σ4N × 100 n: Number of leaves by disease severity f: Index by disease severity N: Number of inspected leaves Index by disease severity Number of lesions per leaf 0 0 1 1 2 2-5 3 6-10 4 11 ~

[Table] Test Example 2 Radish Yellowing Disease Efficacy Test <Method> Radish Yellowing Disease Fungus (Fusarium oxysporum f.
A clay pot with a diameter of 15 cm is filled with clay jars artificially contaminated with chlamydospores of A. raphani. 10 pre-germinated radish seeds (variety: Aokubi Miyaju) are sown in a pot per pot, and the soil is covered with contaminated soil. Immediately, a chemical solution diluted to a predetermined concentration is uniformly applied to the surface, and then lightly sprinkled with water. The pots are then left in the greenhouse and watered accordingly. 60 days after treatment, the presence and severity of disease onset will be investigated according to the following criteria. Disease severity = number of wilted seedlings x 1 + number of duct browned seedlings x 0.5 / number of surveyed seedlings However, the number of plants is 5. <Results>

[Table] Test Example 3 Citrus Black Spot Efficacy Test <Method> When sprouts of potted mandarin oranges (variety: Natsukan) develop, a sufficient amount of a chemical solution diluted to a predetermined concentration was sprayed and then air-dried in a greenhouse. Cultivated on mandarin orange branches
Immediately after spray inoculation with Diaporthe citri conidia, the cells were kept in the dark at a temperature of 23° C. and a humidity of 100% for 2 days. Two days later, the plants were left in a greenhouse, and the degree of disease onset was investigated 30 days after inoculation. However, the number of runs shall be three. Disease severity = Σnf/Σ4N f: Disease severity n: Number of leaves by disease severity N: Total number of leaves surveyed Disease severity Number of lesions/leaf 0 0 1 1~3 2 4~6 3 7~10 4 11~ <Results>

[Table] Test Example 4 Spore germination inhibition test against citrus black spot fungus <Method> Mix conidia of Diaporthe citri cultured on dead citrus branches with a chemical solution, and adjust to approximately 20 conidia per field of view under a microscope at 100x magnification. . Place 0.02ml of this mixed suspension on a glass slide.
After dropping it and keeping it at a temperature of 27℃ and humidity of 100% for 20 hours, it is examined for spore germination by microscopic examination. Each test was repeated twice, and the presence and extent of germination of approximately 200 spores was examined. <Results>

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Claims (1)

[Claims] 1. General formula (In the formula, _R1 is a hydrogen or chlorine atom, _R2 is a diethoxythiophosphoryl group, a _C1 - _C4 alkylcarbonylmethyl group, a benzyl group, a _C1 - _C4 alkylcarbamoyl group, a cyclohexylcarbamoyl group, A cyanodithioacetate derivative represented by a chlorophenylcarbamoyl group or a methoxycarbonyl group. 2 General formula (In the formula, _R1 is a hydrogen or chlorine atom, _R2 is a diethoxythiophosphoryl group, a _C1 - _C4 alkylcarbonylmethyl group, a benzyl group, a _C1 - _C4 alkylcarbamoyl group, a cyclohexylcarbamoyl group, An agricultural and horticultural fungicide whose active ingredient is a cyanodithioacetate derivative represented by a chlorophenylcarbamoyl group or a methoxycarbonyl group.