JPS60255765A - Pyrrole derivative, its production and herbicide and fungicide containing the same - Google Patents

Abstract

NEW MATERIAL:A pyrrole derivative of formula I (A is phenyl which may be substituted; R is H, lower alkyl). EXAMPLE:N-(alpha-cyano-2-pyrrolylmethyl)-3-methylbenzamide. USE:Herbicide or fungicide: it shows powerful preventive and remedial action against late blight and downy mildew in a variety of crop plants, further, it is used as a herbicide in rice plant fields with wide ranges of appropriate period for application. PREPARATION:The reaction of an acid chloride of the formula: A-COCl with aminoacetonitrile of NH2CH2CN gives an acylaminonitrile of formula III (X is halogen), which is allowed to react with a pyrrole derivative of formula IV in the presence of an acid acceptor, preferably in a solvent at 30-50 deg.C to give the compound of formula I.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to pyrrole derivatives, production methods, and herbicides and fungicides containing them. More specifically, amide-substituted pyrrorylacetonitrile derivatives represented by the general formula CI) (wherein A represents an unsubstituted or substituted phenyl group, and R represents a hydrogen atom or a lower alkyl group), methods for producing them, and It relates to herbicides and fungicides containing them.

The present invention relates to herbicides and fungicides useful in agriculture and horticulture. As a fungicide, it is effective against various late blight and downy mildew diseases, and as a herbicide, it is suitable for paddy fields.

[Prior art]

Captafor, against late blight and downy mildew of various crops.
TPN, cabtane or dithiocarbamate compounds are widely used.

However, all of these compounds mainly have a preventive effect against late blight and downy mildew, and are hardly expected to have any therapeutic effect. Therefore, by the time the outbreak of the disease is observed, there is already a sufficient control effect, but it has the disadvantage that it cannot be recognized. When considering the actual time of spraying, it is more or less sprayed after the disease has appeared, and it is difficult to completely control the disease using these compounds. In order to improve these points, new pest control agents have been developed, and currently N-phenyl amino acid esters, such as metalaxyl [N-(2,6-dimethylphenyl)-N-(2'-methoxyacetyl)alanine] methyl ester] etc. are being introduced to the world. However, these N
- Phenyl amino acid ester derivatives have already become a problem due to the appearance of resistant bacteria, and new control agents are desired.

Many compounds have been developed and put into practical use as herbicides for paddy fields. However, due to changes in agricultural practices and an increase in the number of part-time farmers, herbicides with new properties are being developed.

For example, many of the herbicides currently in use cannot be expected to completely kill weeds unless they are applied as soon as possible after puddling. On the other hand, chemicals that may cause phytotoxicity to paddy rice if applied too early are limited to a very narrow period of time. In either case, it can be said that there is a desire for a herbicide that can be used over a wide range of suitable periods and exhibits herbicidal effects no matter when it is used.

Conventionally, many studies have been conducted on pyrrole derivatives having activities as herbicides, fungicides, or insecticides, and many compounds having characteristic physiological activities are known. For example, JP-A-54-110327, 54-10386
No. 5, No. 56-79672, and No. 51-76427 describe the use as a bactericide and an insecticide, but all of them have a large (different) chemical structure from the compound of the present invention. Among these, JP-A-54-10386
No. 5 and No. 56-79672 disclose agricultural and horticultural fungicides. The former 1 () is said to be effective in controlling diseases such as blast, sheath blight, gray mold, scab, sesame leaf blight, and smut. Effective against gray mold, sclerotium of rapeseed, sclerotium of apples, spotted leaf disease of wheat, rice blast, sheath blight, seedling blight, sesame leaf blight, bakanae disease, slug smut, etc. The control potential of amide derivatives has been described, but all of them are mainly aimed at controlling botrytis.Also, many studies have been conducted on amide derivatives, and many characteristic physiologically active compounds are known. Among them, there are many compounds that exhibit herbicidal or fungicidal activity, such as O-methylbenzanilide (Mebel),
0-Methylbenz-m-isopropoxy7anilide (mepronil) etc. have been put into practical use, and as a herbicide, ethyl N
-benzoyl-N-(3,4-dichlorophenyl)-
Known examples include 2-aminopropionate (benzoylprop-ethyl) and N-naphthylphthalamic acid (naptalam).

In addition, as an amide-substituted acetonitrile that is considered to have a chemical structure relatively similar to that of the compound of the present invention, JP-A No. 5
7-167978, 57-176938, and 5
Publication No. 8-69866 discloses herbicides and fungicides.

Originally, the chemical structures of compounds and their physiological activities are completely unpredictable, and even in the group of compounds with basic skeletons similar to those described in 5 above, their activity may be bactericidal or herbicidal. It is a well-known fact that There is no description in JP-A-57-1, and the physiological activity of pyrrole acetonitrile derivatives is completely unknown until now.

[Problem that the invention seeks to solve]

The drugs widely used to control late blight and downy mildew on various crops have mainly preventive effects and cannot be expected to have any therapeutic effects. Therefore, by the time the outbreak of the disease is recognized, sufficient control effects have not been recognized, and the reality is that we are struggling to find control measures.

In addition, most of the herbicides used as herbicides for rice fields cannot be expected to completely control the herbicides unless they are treated as soon as possible after puddling, and the use period for chemicals that may cause chemical damage to transplanted paddy rice is extremely narrow. Limited to a range. Therefore, there is a need for a herbicide that can be used over a wide range of periods and exhibits a control effect no matter when it is used.

In order to solve the above-mentioned problems, the present invention provides a new type of compound that is effective against late blight and downy mildew and has excellent not only preventive effect but also therapeutic effect. It is an object of the present invention to provide compounds with a wide range of suitability with a small amount of oxidation, a method for producing these compounds, and herbicides and fungicides containing them.

[Means and effects for solving the problem] The present inventors have been conducting research on compounds having completely new chemical structures that have excellent not only preventive effects but also therapeutic effects against various epidemics. We have also conducted research to find compounds that have fewer restrictions on the timing of treatment as herbicides for paddy fields. As a result, the pyrrole derivative represented by the general formula (I) R (wherein A represents an unsubstituted or substituted phenyl group, and R represents a hydrogen atom or a lower alkyl group) is effective against late blight and downy mildew on various crops. The present invention was completed based on the discovery that it exhibits an excellent control effect against diseases and has a wide range of suitability as a herbicide for paddy fields.

The virole derivative of the present invention is represented by the general formula (I), and specific examples of the group include phenyl group, m-chlorophenyl group, p-chlorophenyl group, p-fluorophenyl Lm-bromphenyl group, m-bromphenyl group, -iodophenyl group, 2.
4-dichlorophenyl group, 3.4-dichlorophenyl group, 3,5-dichlorophenyl group, 3.4.5-) IJ
Dichlorophenyl group 3゜5-difluorophenyl group, m
-trifluoromethylphenyl group, p-)IJ fluoromethylphenyl group, m-tolyl group, p-)ruyl group,
p-isopropylphenyl L 3.4-methylenedioxyphenyl group, m-nitrophenyl group, p-nitrophenyl group, 3.5-dinitrophenyl group, m-cyanophenyl L p-cyanophenyl group, m-methoxyphenyl group, p-methoxyphenyl group, 3゜4-dimethoxyphenyl group, 3,5-dimethoxyphenyl group, 3.4.5-
) Rimethoxyphenyl group nato, and the substitution position on the phenyl ring is 3-94- and/or 5-
- position is preferred.

The group R is a hydrogen atom or a lower alkyl group, preferably a hydrogen atom or a methyl group.

The general formula (I) is one of the structures that best represents the structure of the virol derivative of the present invention. For some of the compounds that can be included within the scope of general formula (I), tautomers exist in which the hydrogen atom is moved to another part of the molecule and the chemical bonds between atoms in the molecule are transferred. obtain. An example of this is the following formula % Formula % General formula (1) is a formula that includes and represents such tautomeric compounds as long as they exist. General formula (I) also includes various structures, such as those in which molecules are arranged in a crystal lattice, structures in which one part of the molecule cannot freely rotate around another part, and the presence of intramolecular or intermolecular bonds. It also includes modified structures based on physical classification based on the above, optical isomers, and geometric isomers.

Furthermore, the present invention also provides a method for producing the pyrrole derivative represented by the general formula (I) according to the present invention. That is, general formula (II) A-CONI-ICI-1
Acylaminonitriles represented by 2CN (n) (wherein A represents an unsubstituted or substituted phenyl group) are treated with a halogenating agent in a solvent to obtain the general formula (III) A-C
ONI-1cH-CN (I) (wherein, A and R have the above-mentioned meanings) This is a method for producing a virol derivative represented by .). Next, the outline of the production method of the present invention will be explained according to the following reaction scheme-1.

Reaction Scheme-1 GIII) (1) Acylaminoacetonitrile (I
I) is obtained. Treatment with bromine in a suitable solvent yields the brominated intermediate (IJJ). Examples of solvents include aliphatic halides such as dichloromethane, chloroform, carbon tetrachloride, and 1,4-dichloroethane, aliphatic carboxylic acid esters such as methyl acetate, ethyl acetate, isopropyl acetate, and ethyl propionate, and carbon disulfide. can be mentioned. Good results are obtained using ester solvents such as ethyl acetate. The reaction temperature is in the range of 0 to 120°C, preferably room temperature. Note that this reaction is more preferably carried out under an inert gas atmosphere. Since this brominated intermediate G11) is unstable, it is used immediately after its preparation is completed. It is also possible to replace bromine with other rogogenation reagents, such as chlorine, phosphorus oxychloride, sulfuryl chloride, phosphorus tribromide, etc. This bromine compound (III) is reacted with a virol derivative represented by the general formula 偕) (wherein R represents a hydrogen atom or a lower alkyl group). This reaction can be carried out in the presence of an acid acceptor.

Examples of acid acceptors include organic bases such as triethylamine, dimethylaniline, pyridine, inorganic bases such as ammonia, potassium carbonate, sodium carbonate, sodium bicarbonate, sodium hydroxide, ammonium carbonate, and organometallic compounds such as butyllithium. However, it is not limited to these, of course. Preferably, this reaction is carried out in a solvent or diluent. Pyridine can be used both as a solvent and as an acid acceptor.

Since this reaction does not have good stability of intermediates, very high temperatures are not desirable, and since it is an exothermic reaction, it is desirable to conduct it under cooling. At low temperatures, reaction intermediates tend to precipitate, slowing down the reaction rate and making it impractical.
It is desirable to conduct the reaction at 50°C, preferably -20 to 20°C. The virol derivative (I) produced in this reaction can be easily isolated and purified by conventional methods.

Furthermore, the present invention provides a herbicide and a fungicide characterized by containing the virol derivative represented by the general formula (1) according to the present invention as an active ingredient.

When using the compound of the present invention as a herbicide, the amount of application varies depending on the growth stage of the weed, the type of weed, the type of preparation, the application method, various environmental conditions, etc., but it is usually 0.00. 1 to 10 to 9 is suitable, preferably 0.3 to 3 to 9/' hectares.

When the compound of the present invention is used in field crops, it is advantageous to apply it before weeds emerge or during the period when weeds are at their peak.

On the other hand, when applied in paddy fields, it has a wide range of suitable periods against gramineous weeds, and does not harm transplanted paddy rice.
It can be widely used from before the emergence of grass weeds to the growing season.

In addition, when the compound of the present invention is used as a fungicide, diseases such as tobacco late blight, pepper blight, cucumber rot, pudate rot, gray mold, rice blast, groundnut brown spot, beet brown spot, apple scab, and aphanomyces Examples include various soil diseases caused by fungal isobaria and clubroot diseases of cruciferous vegetables. Application methods for the compound of the present invention include seed disinfection, foliage spraying, soil treatment, etc., but any application method commonly used by those skilled in the art will exhibit sufficient efficacy. The application amount and concentration vary depending on the target crop, the target disease, the degree of disease occurrence, the dosage form of the compound, the application method, various environmental conditions, etc.

When the compound of the present invention is used as a herbicide or fungicide, it may be combined with other biologically active compounds, such as other herbicides, fungicides, insecticides, pesticides such as plant growth regulators, soil conditioners, or fertilizing substances. Not only can it be used in combination with these, but it can also be applied as a mixed preparation with these.

The compounds of the invention are preferably applied in the form of a composition in admixture with a carrier including solid or liquid diluents. As used herein, carrier means an inorganic or organic substance, synthetic or natural, which is incorporated to aid in the delivery of the active ingredient to the site to be treated and to facilitate storage, transport and handling of the active ingredient compound.

Suitable solid carriers include clays such as montmorillonite and kaolinite, inorganic substances such as diatomaceous earth, clay, talc, vermiculite, gypsum, calcium carbonate, silica gel, and ammonium sulfate, vegetable organic substances such as soybean flour, sawdust, and wheat flour; Examples include urea.

Suitable liquid carriers include aromatic hydrocarbons such as toluene, xylene and cumene, paraffinic hydrocarbons such as kerosene and mineral oil, halogenated hydrocarbons such as carbon tetrachloride, chloroform and dichloroethyl ketone, acetone and methyl ethyl ketone. In order to enhance the efficacy of the compounds of the present invention, ketones, dioxane, ethers such as tetrahydrofuran, methanol, propatool, ethers, etc. may be used alone or depending on the purpose, taking into consideration the dosage form of the preparation, the application situation, etc. The following adjuvants can also be used in combination:

For the purpose of emulsification, dispersion, spreading, wetting, binding, stabilization, etc., water-soluble bases such as genin sulfonate, nonionic surfactants such as alkylbenzene sulfonate, alkyl sulfate, calcium stearate, wax, etc. lubricants, stabilizers such as isopropylhydrodiene phosphate, and others such as methylcellulose, carboxymethylcellulose, casein, and gum arabic. However, these components are not limited to the above.

The amount of active ingredient in the composition of the compound of the present invention is usually 0.
The content is 5 to 20% by weight, 10 to 90% by weight for wettable powders, 0.1 to 20% by weight for granules, 5 to 50% by weight for emulsions, and 10 to 90% by weight for flowables.

〔Example〕

Representative examples of the compounds of the present invention are shown as well as their physical properties, nuclear magnetic resonance spectrum data, and IK-IK.

Next, a detailed explanation of the method for producing the compound of the present invention will be given with reference to a synthesis example.

Synthesis Example-I N-(α-cyano-2-pyrrolylmethyl)
-3-7 Synthesis of Dolpenzamide (Compound No.-5) 3. Synthesis of 3-methylbenzoylaminoacetonitrile synthesized from 3-methylbenzoyl chloride and aminoacetonitrile by a conventional method. To a 100-solution of dry ethyl acetate of O 9 (0,017 mol) was added 2.89 (0
,018 mol) at once. Gently warm the reaction solution until the bromine color disappears, then immediately reduce the temperature to 0.
The temperature was below ℃. Lateral pressure adjusted virol 1.29 (0,0
18 mol) and triethylamine 3.87 (0,0
A solution of 37 mo I) in ethyl acetate was added dropwise to the previous solution. After completion of the dropwise addition, the mixture was further stirred for 30 minutes at 0° C. or below.

The triethylhydrobromide salt was removed in the oven, and the solution F was distilled under reduced pressure to remove the solvent. When ethyl ether is added to the solid residue, suspended, and filtered, N-(α-cyano-2
-pyrrolylmethyl)-3-methylbenzamide was obtained as a white solid. Yield: 1.99 (yield: 46.8%).

Synthesis example -2N-(α-cyano-2-pyrrolylmethyl)-
Synthesis of 3,5-dichlorobenzamide (compound number-6) 3.5-dichlorobenzoylaminonitrile 4.0 g
2.89 (0,018 mol) of bromine was added all at once at room temperature to a 100% solution of dry ethyl acetate (0,017 mol), and the mixture was stirred at the same temperature until the color of bromine disappeared. A mixture consisting of 2,0 mol of virol (0,030 mol), 10.09 mol of triethylamine (0,098 mol), and 20 ml of dioxane was cooled in an ice bath, and a photopressure was applied to this mixture at 10° C. or less while stirring. A solution of bromide in ethyl acetate was added dropwise. After the dripping is complete, cool for 30 minutes with water.
After continuing the reaction for several minutes, 100 ml of water was added to dissolve the precipitated triethylamine hydrobromide salt. After separating the oil layer, washing with water and drying, the solvent was distilled off under reduced pressure, and ethyl ether was added to the solid residue, which was suspended and filtered.
2.39 -(α-cyano-2-pyrrolylmethyl)-3,5-dichlorobenzamide was obtained as a white solid. Yield 45.9%.

The acylaminonitriles used as starting materials can be easily produced by reacting acyl halides with aminoacetonitrile in a conventional manner.

For example, a 10% aqueous sodium hydroxide solution is cooled under pressure in ice water, and aminoacetonitrile sulfate is added and dissolved while stirring. A toluene solution of acid halide is added dropwise to this solution while cooling with water, and after the addition is complete, the solution is further stirred at the same temperature. The precipitated crystals were collected through a suction port, and the resulting crystals were washed with toluene and water, and then dried, and used.

Next, the formulation method of the agricultural and horticultural fungicides and herbicides of the present invention will be explained using formulations.

The active ingredient compounds are indicated by compound numbers in Table 1 above. "Part" represents "part by weight."

Formulation Example-1 Powder Compound (1): 3 parts, diatomaceous earth: 20 parts, white clay: 30
and 47 parts of talc were uniformly ground and mixed to obtain 100 parts of a powder.

Formulation Example-2 Wettable powder Compound (2): 30 parts, diatomaceous earth: 44 parts, clay: 20 parts, sodium ligninsulfonate: 4 parts and sodium alkylbenzenesulfonate: 2 parts were uniformly ground and mixed, and mixed with water. 100 parts of Japanese preparation were obtained.

Formulation Example-3 Emulsion Compound (3): 15 parts, Cyclohexanone: 15 parts,
60 parts of xylene di and 10 parts of Tsurpol (a surfactant manufactured by Toho Chemical Co., Ltd.) were uniformly dissolved and mixed to obtain 100 parts of an emulsion.

Formulation example - 4 grains Compound (4): 1 part, bentonite: 78 parts, talc: 20 parts and sodium ligninsulfonate =
After mixing 1 part, adding an appropriate amount of water and kneading, granulate using an extrusion granulator in a usual manner, and after drying, granules 1
I got 00 copies.

Formulation Example-5 Granule Compound (10) Nia part, 71 parts of polyethylene glycol nonylphenyl ether, 3 parts of polyvinyl alcohol, and 89 parts of Flam are uniformly mixed, hydro-granulated, dried, and 100 parts of the granule are prepared. Obtained.

Formulation Example-6 Powder Compound (6): 2 parts, calcium carbonate: 40 parts and clay = 58 parts were uniformly ground and mixed to obtain 10 parts of a powder.

Formulation Example 7 Wettable powder Compound (5): So part, Merck 40 parts, sodium lauryl phosphate: 5 parts, and sodium alkylnaphthalene sulfonate: 5 parts were mixed to obtain 100 parts of a wettable powder.

Formulation example-8 Wettable powder compound (7): 50 parts, Sodium lignin sulfonate:
10 parts, sodium alkylnaphthalene sulfonate: 5 parts,
10 parts of white carbon and 25 parts of Keisoushi were mixed and ground to obtain Ino part of the wettable powder.

Formulation Example-9 Flowable agent compound (15): 40 parts, carboxymethyl cellulose: 3 parts, lJ geninsulfonate sodium: 2 parts, dioctyl sulfosuccinate sodium salt: 1 part and water: 54 parts were wet ground in a sand grinder. 100 parts of a flowable agent was obtained.

Next, the efficacy of the compounds of the present invention as herbicides and fungicides will be explained using test examples.

Test Example-1 Pre-emergence weeding test in a rice field A/'5000 Wagner pots were filled with soil, and seeds of Japanese millet, broad-leaved weeds (Kikashigusa, Azena, Aspergillus, etc.), firefly, Helaomodaca, and Cyperus japonica were sown;
It was in a flooded state. Two paddy rice seedlings (2-3 leaf stage) that had been raised in advance were used as one plant, and the two plants were transplanted and grown in a greenhouse.

3 days after transplanting paddy rice weeds started to appear We investigated the appearance of weeds and chemical damage to paddy rice after 8 days for each test compound.Table 2
I got the result.

In this table, the degree of chemical damage to crops and the herbicidal effect on weeds are expressed by comparing the emergence or growth of crops or weeds with that of the untreated air-dried type according to the evaluation criteria below. The test compounds were indicated by compound numbers in Table 1 above (the same applies hereinafter).

Evaluation criteria: 0 Diagonal tricks, 4R madness, 91~
100% 11171~90% 21141~70% 3 +1 11~40% 4116~10% 5 II Q~ 5% Test Example-2 Paddy growing season weeding test a15,000 Seeds of Japanese cypress, Japanese azalea, Japanese cypress, etc.), Japanese firefly, Japanese cypress, and Japanese cypress were sown and flooded. Two paddy rice seedlings (2-3 leaf stage) that had been raised in advance were used as one plant, and the two plants were transplanted and grown in a greenhouse. During the weed growth period 12 days after transplanting paddy rice, weed growth conditions and chemical damage to paddy rice were investigated 30 days after each test treatment, and the results shown in Table 3 were obtained. In this table, the degree of chemical damage to crops and the growth status of weeds are shown in the test example.
It was expressed according to the evaluation criteria shown in 1.

From the results in Tables 2 and 3, the compound of the present invention is effective against paddy field weeds as a herbicide for paddy fields in a wide range of suitable periods.
It is clear that the plant does not show any phytotoxicity to paddy rice.

Test Example-3 Potato Phytophthora control test (preventive effect) Potatoes grown in bots in a greenhouse (variety Kootoshiaku, plant height approximately 25 cm) were treated with prescribed concentrations of chemicals (each test compound was applied according to the method of Formulation Example-7 above). Prepare a hydrating powder, dilute it with water to a predetermined concentration, and use a spray gun (1,
The seeds were sprayed at 50 kg/cd per 3 pots and air-dried. A zoospore suspension was prepared from potato Phytophthora blight bacteria that had been previously cultured on potato sections for 7 days. The potato plants sprayed with the chemical in suspension were inoculated, and the test plants were kept at 17 to 19° C. and a humidity of 95% or higher for 6 days, and then the degree of lesion formation was investigated.

The severity index of each leaf was determined by observation and evaluation as shown below, and the disease severity was determined for each plot as shown below.

The evaluation criteria are as follows.

Disease severity index Lesion area ratio 0:n, Q% 1:n2 1-5% 2:n, 6-25% 3:n4 26-50% 4:n, 51% or more 01~. represents the number of individuals with each disease severity index.

The results are shown in Table-4.

Test Example 4 Potato late blight control test (therapeutic effect) As in Test Example 3, a potato late blight zoospore suspension was prepared and inoculated onto potato plants by upward pressure spraying in the same manner. 2
After maintaining the temperature at 17 to 19°C and humidity of 95% or more for 0 hours, a hydrating powder was prepared according to the method of Formulation Example 7 above, and was diluted to a predetermined concentration. ) was applied using a spray gun (9/c++I on 1,0). After air-drying, the specimens were kept at 17-19° C. and humidity of 95% or higher for 5 days, and then the extent of lesion formation was examined.

The evaluation criteria and disease severity display method were as shown in Test Example-3.

The results are shown in Table-5.

Test Example-5 Cucumber and disease control test (preventive effect) Cucumbers grown in pots in a greenhouse (variety: Sumo half-day,
Spray gun (1, 0~/
cJ) was used to spray 30 mg per 3 pots and air dry. Downy mildew bacteria were collected from lesions on cucumber leaves infected with downy mildew, a spore suspension was prepared with demineralized water, and the suspension was sprayed for inoculation. Immediately place the inoculated pot at 18-20℃ and humidity at 95℃.
% or more for 24 hours, then put it in a greenhouse (room temperature 18~
After 7 days of IIC transfer (27°C), the degree of lesion formation was examined. The evaluation criteria and disease severity display method were as shown in Test Example 3. The results are shown in Table-6.

Test Example 6 Cucumber and disease control test (therapeutic effect) In the same manner as in Test Example 5, a suspension of cucumber and disease spores was prepared and inoculated by spraying onto cucumbers grown in pots in a greenhouse. After maintaining the temperature at 18 to 20°C and humidity of 95% or higher for 24 hours, the drug at a predetermined concentration (prepare a wettable powder for each test compound according to the method in Formulation Example 7 above, and add water to the predetermined concentration). diluted) with a spray gun (1,0 IC
9/CIIJ) was used to spray 30 mg per 3 pots. The plants were transferred to a greenhouse (room temperature: 18-27'C) and 7 days later, the degree of lesion formation was examined.

The evaluation criteria and disease severity display method were as shown in Test 3.

The results are shown in Table-7.

Control compounds A and B are both commercially available agents for controlling potato late blight and cucumber blight.

Control compounds C and D are compounds described in JP-A-57-167978.

From the results shown in Tables 4 to 7, the compound of the present invention clearly shows a preventive effect at a lower dose than the currently commercially available fungicides A and B, and appears to have a relatively similar chemical structure. It can be seen that the effect is superior compared to control compounds C and D. Bactericides A and B have been put into practical use for their therapeutic effects.
has no such effect at all, and comparative compounds C and D have weak therapeutic effects, but it can be seen that the therapeutic effects of the compounds of the present invention are clearly superior.

〔Effect of the invention〕

As is clear from the above explanation, the production method of the present invention can produce a compound of the general formula (I) of the present invention (wherein A represents an unsubstituted or substituted phenyl group, and R represents a hydrogen atom or a lower alkyl group). ) is obtained in substantially one step.

As a paddy field herbicide, these virol derivatives related to the compounds of the present invention have excellent herbicidal action over a wide range of periods of use against paddy field weeding, where conventional herbicides had a narrow suitable period and could not be expected to have sufficient herbicidal effects. In addition, as a control agent for diseases caused by algae and fungi on various crops - Phytophthora A and downy mildew - it has been shown to have a preventive effect at a lower dose than conventional drugs, and also has therapeutic effects that conventional drugs did not have. It also has excellent properties. Pesticides containing these provide useful herbicides and fungicides.

patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (6)

[Claims] (1) General formula (I) In the N C formula, A represents an unsubstituted or substituted phenyl group, and R represents a hydrogen atom or a lower alkyl group. ) Pyrrole derivative represented by (2) A is unsubstituted or the 3-14- and/or 5-position of the ring is a methyl group, trifluoromethyl group, methoxy group, methylenedioxy group, chlorine atom, fluorine atom, nitro group or cyano group The pyrrole derivative according to claim 1, which is a substituted phenyl group. (3) The pyrrole derivative according to claim 1, wherein R is a hydrogen atom. (4) The pyrrole derivative according to claim 1, wherein R is a methyl group. (5) Acylaminonitriles represented by the general formula (II) A-CONHCH2CN ([) (wherein A represents an unsubstituted or substituted phenyl group) are treated with a chlorogenating agent in a solvent. General formula (rlI) A-CONHCI-I
CN 1 (■) (In the formula, A has the meaning described above, and X represents a).logen atom. ), and this intermediate is then placed in the presence of an acid acceptor. ) A method for producing a pyrrole derivative represented by general formula (I) (wherein A and R have the above-mentioned meanings). (6) General formula (I) (wherein, A represents an unsubstituted or substituted phenyl group, and R represents a hydrogen atom or a lower alkyl group) as an active ingredient. herbicides or fungicides.