JPH02250873A - 1,2,4-oxadiazole derivative and herbicide containing the same derivative as active ingredient - Google Patents

Abstract

NEW MATERIAL:A compound of formula I [either of R<1> and R<2> is a group of formula II (X<1> and X<2> are halogen); the other is 1-6C alkyl, 1-6C halogenoalkyl, 3-6C cycloalkyl or (substituted) aryl; R<3> is H, 1-6C alkyl, 1-6C halogenoalkyl, 2-4C alkenyl, 3-4C alkynyl, (substituted)aryl, (substituted)pyridyl, 3-6C alkoxycarbonylalkyl or 2-6C hydroxycarbonylalkyl]. EXAMPLE:3-(2-Fluoro-4-chloro-5-methoxyphenyl)-5-methyl-1,2,4-oxadiazole. USE:Useful as a herbicide having a wide herbicidal spectrum and an excellent activity even in a small amount use. PREPARATION:For example, a compound of formula III is reacted with an acid chloride or acid anhydride in the presence of a base in a solvent to provide the compound of formula I.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a novel 1,2,4-oxadiazole derivative that has not been described in any literature, and a herbicide containing the same as an active ingredient. Summary of the Invention J, Org, Cheese, 44.4160 (
1979) shows an example of the synthesis of 3-substituted phenyl-1,2,4-oxadiazole derivatives, but does not describe their physiological activity at all. The present inventors synthesized novel 1.2.4-oxadiazole derivatives and investigated their physiological activities, and found that they have herbicidal activity and can be applied over a wide herbicidal spectrum at reduced application rates. It has also been found that the compound exhibits excellent selective herbicidal activity, and can exhibit excellent herbicidal activity by, for example, soil treatment and foliar treatment. Thus, according to the invention - maximum (1) [where R1
and R2, one of which is a formula group, and the other is an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or may be substituted. is an aryl group, where x' and x'' are the same or different halogen atoms, and R3 is hydrogen, an alkyl group having 1 to 6 carbon atoms, and 1 to 6 carbon atoms.
haloalkyl group, alkenyl group having 2 to 4 carbon atoms, alkynyl group having 3 or 4 carbon atoms, optionally substituted aryl group, optionally substituted pyridyl group, alkoxycarbonylalkyl group having 3 to 6 carbon atoms, or carbon 1,2,4-oxadiazole derivative represented by the following formula can be provided. Furthermore, according to the present invention, it is possible to provide a herbicide characterized by containing the compound of the above formula (I) as an active ingredient. Effects of the Invention The 1,2,4-oxadiazole derivative represented by the above formula (I) of the present invention is a novel compound that has not been described in any literature as far as the inventors know. The l,2,4-oxadiazole derivative represented by the above formula (I) of the present invention has 2,4-
It is characterized by having a dihalogeno-5-substituted phenyl group or having a substituent at the other 3- or 5-position, and due to its structural characteristics, the 1,2,4-oxadiazole derivative of formula (1) has a herbicidal property. It is thought that it exhibits excellent physiological activity as a drug. The herbicide of the present invention has a wide herbicidal spectrum, and furthermore,
This herbicide has the excellent property of fully exhibiting its herbicidal activity with an extremely small amount used compared to ordinary herbicides. DETAILED DESCRIPTION OF THE INVENTION Next, the present invention will be described below. The 2.4-oxadiazole derivative will be explained in more detail. In the dihalophenyl group substituted as R1 or R1 in the above-mentioned maximum (I), XI and Xz are the same or different halogen atoms, examples of which are fluorine, chlorine, bromine or iodine; is preferred. Further, as R3 in the R''O- group substituted with the dihalophenyl group, in addition to (i) hydrogen, (if) an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, 1so-propyl, n-butyl, 1
Examples include so-butyl, 5ec-butyl, ter-butyl, pentyl, and structural isomers thereof, and among these, alkyl groups having 1 to 3 carbon atoms are preferred, and (iii) haloalkyl groups having 1 to 6 carbon atoms are , 1 to 6 halogens, especially fluorine or chlorine, are suitable, such as chloromethyl, chloroethyl, dichloroethyl, difluoromethyl, trifluoroethyl or trifluoroethyl. Among these, an alkyl group having 1 to 3 carbon atoms and having 1 to 3 Il of halogen is preferable, and (iv) an alkenyl group having 2 to 4 carbon atoms includes, for example, vinyl, allyl or isobutenyl, and ( V) Examples of the alkynyl group having 3 or 4 carbon atoms include propargyl or butyryl, and (vi) the aryl in the optionally substituted aryl group includes a phenyl group, a naphthyl group or a biphenyl group, preferably a phenyl group. These may have 1 to 5, preferably 1 to 3 substituents, and the substituents include alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, , halogen, trifluoroethyl group, etc. Specific examples include phenyl, 3-
Examples include trifluoroethylphenyl or 3,4-dichlorophenyl, and (vli) the optionally substituted pyridyl group includes a pyridyl group that may have the same substituent as shown in (Vi) above. Specific examples include pyridyl, 3-chloro-5-trifluoromethyl-2-pyridyl, etc. (viii) Alkoxy in the carbonyl alkyl group having 3 to 6 carbon atoms is an alkoxy group having 1 to 4 carbon atoms. For example, methoxy, ethoxy, propoxy or butoxy is shown, and the alkyl group is methyl, ethyl, propyl or butyl having 1 to 4 carbon atoms. Specifically, C4H*OCC(CHs)*-1 etc. can be mentioned.
(ix) Hydroxycarbonylalkyl having 2 to 6 carbon atoms - The preferred group is one having 2 to 4 carbon atoms. In the above-mentioned maximum (I), one of R1 and R1 is the dihalophenyl group described above, and the other substituent will be explained below. That is, in R1 and R1, the other group that is not the dihalophenyl group is (a) an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, is. -propyl, n-butyl, 1so-butyl, 5ec-butyl, ter-butyl, pentyl and structural isomers thereof, among which alkyl groups having 1 to 4 carbon atoms are preferred; (b) alkyl groups having 1 to 4 carbon atoms; As the haloalkyl group of ~6, the above alkyl group (ii) substituted with 1 to 6 halogens, especially fluorine or chlorine, is suitable, such as chloromethyl, chloroethyl, dichloroethyl, difluoromethyl, trifluoromethyl. or trifluoroethyl, and among these, an alkyl group having 1 to 3 carbon atoms and having 1 to 3 halogens is preferable, and (c) a cycloalkyl group having 3 to 6 carbon atoms is, for example, cyclopropyl. , cyclobutyl, cyclopentyl or cyclohexyl, etc., and examples of the aryl group in (d) optionally substituted aryl group include phenyl group, naphthyl group or biphenyl group, preferably phenyl group, which has 1 to 5 , preferably 1 to 3 (may have 1 substituent, such as an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen, a trifluoromethyl group, etc., and specific examples include 3-trifluoromethyl or 3,4-dichlorophenyl.In the above-mentioned maximum (1), R1 is the dihalophenyl group, and R1 is the above-mentioned (a) to (b). 1 is a substituent of
, 2,4-oxadiazole derivatives are preferred compounds because they are easy to synthesize. The above-mentioned maximum (1) in the present invention may be obtained by any method. Also, the above-maximum (I
) may form a salt with an agriculturally acceptable acid. The above-mentioned maximum (1) is, for example, the following reaction formula A and reaction formula B.
However, the present invention is not limited to products manufactured by this method. Reaction formula A /Y' (II) [wherein R'', XI and xt are the same as defined above,
R4 is an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an optionally substituted aryl group] As shown in the above reaction formula A, Benzamidoxime (I
The compound of formula (I-1) of the present invention can be produced by reacting I) with an acid chloride or an acid anhydride, for example, in an organic solvent or in the absence of a solvent, in the presence of a base. In the reaction, the acid chloride or acid anhydride is used in an amount of 1 to 3 molar equivalents, preferably ii, relative to compound (II). The reaction is carried out using 5 molar equivalents at a temperature of room temperature to about 110° C. for 1 to 8 hours. The acid chloride or acid anhydride used in the above reaction is one having R4 as a residue, specifically the acid chloride or acid anhydride corresponding to the groups listed in (a) to (d) above. be. As the acid chloride, for example, acetyl chloride, propionyl chloride, butyryl chloride, benzoyl chloride, cyclopropanecarbonyl chloride, or pivaloyl chloride, etc. are used, and as the acid anhydride, for example, acetic anhydride,
Propionic anhydride, trifluoroacetic anhydride, pivalic anhydride, etc. are used. Examples of the base used include organic bases such as pyridine and triethylamine. After completion of the reaction, the target compound of the present invention can be isolated by pouring the reaction mixture into water and treating it according to conventional methods such as extraction with an organic solvent, recrystallization, and column chromatography. Reaction formula B [where R3, xl and X! is the same as the above definition and %
R' is an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an optionally substituted aryl group 1 As shown in the above reaction formula B , acid chloride (III) and amidoxime (IV) are reacted, for example, in an organic solvent or in the absence of a solvent, in the presence of a base to obtain the formula (I-2) of the present invention.
compounds can be manufactured. The reaction is carried out using 1 to 3 molar equivalents, preferably 1 to 1.5 molar equivalents, of acid chloride relative to compound (IV) at a temperature of room temperature to about 110°C for 1 to 8 hours. The amidoxime (■) used in the above reaction is R
4 as a residue, specifically the above (a
) to (d). Examples of amidoximes include methylamidoxime,
Ethylamidoxime, trifluoromethylamidoxime, cyclopropylamidoxime, phenylamidoxime, etc. are used. Examples of the base used include organic bases such as pyridine and triethylamine. After completion of the reaction, the target compound of the present invention can be isolated by pouring the reaction mixture into water and treating it according to conventional methods such as extraction with an organic solvent, recrystallization, and column chromatography. Next, the present invention will be explained in more detail with reference to Examples. Example 1 3-(2-fluoro-4-chloro-5-methoxyphenyl)-5-methyl-1,2,4-oxadiazole (
Synthesis of compound commercially available 1); 11 (0,004 mol) of 2-fluoro-4-chloro-5-methoxybenzamidoxime was dissolved in 10- of anhydrous pyridine, and 450 mg (0,0
06 mol) was added at room temperature. Next, the reaction solution was heated to 110°C.
The mixture was stirred for 2 hours. The reaction solution was extracted with ethyl acetate, and the organic layer was washed with water and dried over anhydrous magnesium acetate. column chromatography

[Eluent: ethyl acetate/hexane-115 (solution ratio)] Purified with 910 eg (yield 80%) of 3-(
2-Fluoro-4-”Cl-5-methoxyphenyl)-
5-methyl-1,2,4-oxadiazole was obtained. The compounds of the present invention shown in Table 1 were synthesized in the same manner as in the above examples. The results are shown in Table 1. Further, NMR (nuclear magnetic resonance spectrum) data of the compounds in Table 1 are shown in Table 2. In Table 1, t-Bu represents t-C4H. Table 1 Table 2 Example 2 Synthesis of 5-(2-fluoro-4-chloro-5-methoxyphenyl)-3-methyl-1,2,4-oxadiazole (compound No. 33); 12 (0, 014 mol)
of methylamidoxime was dissolved in lOO20 of anhydrous pyrimidine and 4.71 (0,021 mol) of 2-fluoro-4-chloro-5-methoxybenzoyl fluoride was dissolved.
was added at room temperature, and the reaction solution was extracted with ethyl acetate, and the organic layer was washed with water and dried over anhydrous magnesium acetate. It was purified by column chromatography [eluent: ethyl acetate/hexane-115 (volume ratio)] to obtain 2.51 (yield 75%) of 5-(2
-Fluoro-4-chloro-5-methoxyphenyl)-3
-Methyl-1,2,4-oxadiazole was obtained. The compounds of the present invention shown in Table 3 were synthesized in a manner similar to the above-mentioned Examples. The results are shown in Table 3. Further, NMR (nuclear magnetic resonance spectrum) data of the compounds in Table 3 are shown in Table 4. In Table 3, t-Bu represents t-C4H. Table 4 The compound represented by the above formula (I) of the present invention has extremely high herbicidal activity, so it shows extremely excellent herbicidal activity even when used in a small amount, and has high safety against cultivated crops. and can be a useful herbicide in agriculture. The compounds of the present invention can effectively control various weeds growing in paddy fields and fields from the pre-emergence stage to the growing season. For example, it is possible to control annual weeds that occur in rice fields, such as Japanese grasshopper, Japanese grasshopper, Japanese grasshopper, Japanese aphrodisiac, and Japanese firefly, as well as perennial weeds such as Japanese grasshopper, Japanese grasshopper, Japanese cypress, and Japanese black grub. In addition, annual weeds such as barnyard grass, crabgrass, blackberry, foxtail grass, sparrowweed, chickweed, polygonum, barnyard grass, Japanese velvet, whiteweed, American goldenrod, Japanese fir, pigweed, shepherd's purse, ashweed, chiliflower, yellowtail, and buckwheat are also included. Perennial weeds such as Japanese perennial grass, bindweed, johnson grass, and grasshopper can also be controlled. In particular, the compound of the present invention exhibits strong weed activity against annual broad-leaved weeds growing in fields, such as bluegrass, purslane,
Japanese fir, Japanese lily, Japanese lily, Japanese knotweed, Japanese knotweed, Japanese chickweed, shepherd's purse, Japanese apricot,
It is possible to effectively control weeds such as morning glory, oxalis, walrus, plantain, oxalis, oxalis, and other weeds. Furthermore, the compounds of the present invention can effectively control annual and perennial weeds that occur not only in paddy fields and fields, but also in agricultural lands such as orchards and mulberry gardens, and in non-agricultural lands such as lawns and ridges. Moreover, the compound of the present invention has high safety against cultivated crops, and is particularly useful for growing useful legumes such as rice, corn, wheat, and barley, and useful broad-leaved crops such as soybean and cotton. Does not cause drug damage to the extent that it becomes a problem. When using the compound (I) of the present invention as a herbicide,
It is mixed with carriers, diluents, additives, and auxiliaries by methods known per se to prepare formulations commonly used as agricultural chemicals, such as powders, wettable powders, emulsions, aqueous solutions, and flowables. Ru. Also other pesticides, such as fungicides,
It can be mixed with or used in combination with insecticides, acaricides, herbicides, plant growth regulators, fertilizers, soil conditioners, and the like. In particular, by using it in combination with other herbicides, it is possible to not only reduce the amount of chemicals used and save labor, but also to expand the spectrum of weeds due to the synergistic action of both herbicides and to achieve even higher effects due to their synergistic action. Carriers or diluents used in formulation include:
Commonly used solid or liquid carriers may be used. Examples of solid carriers include clays such as kaolinite group, montmorillonite group, or attapulgite group, talc, mica, waxite, pumice, vermiculite, gypsum, calcium carbonate, dolomite, diatomaceous earth, magnesium lime, and phosphorus. Inorganic substances such as ashstone, zeolite, anhydrous silicic acid, and synthetic calcium silicate; Vegetable organic substances such as soybean flour, tobacco powder, walnut flour, wheat flour, wood flour, starch, and crystalline cellulose; Coumaron resin, petroleum resin, and alkyd. Examples include synthetic or natural polymeric compounds such as resins, polyvinyl chloride, polyalkylene glycols, ketone resins, ester cassems, copal gum, and dammar gum; waxes such as carnauba wax and beeswax; and urea. Suitable liquid carriers include, for example, paraffinic or kerosene, mineral oil, spindle oil, white oil, etc.
Thenic hydrocarbons; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, and methylnaphthalene; chlorinated hydrocarbons such as carbon tetrachloride, chloroform, trichlorethylene, monochloroflbenzene, orthochlorotoluene; dioxane, tetrahydrofuran ethers such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, acetophenone, isophorone; esters such as ethyl acetate, amyl acetate, ethylene glycol acetate, diethylene glycol acetate, diptyl maleate, diethyl succinate; methano- Alcohols such as Ay, n-hexanol, ethylene glycol, diethylene glycol, cyclohexanol, and benzyl alcohol; ether alcohols such as ethylene glycol ethyl ether, ethylene glycol phenyl ether, and diethylene glycol ethyl ether j! [Nidimethylformamide,
Examples include polar solvents such as dimethyl sulfoxide, water, and the like. In addition, emulsification, dispersion, wetting, spreading, spreading, binding, disintegration adjustment, active ingredient stabilization, flowability improvement, etc. of the compound of the present invention,
Surfactants and other auxiliary agents may also be used for purposes such as rust prevention and anti-freezing. Messenger. Examples of surfactants that can be used include nonionic, anionic, cationic, and zwitterionic surfactants, but usually nonionic and/or anionic surfactants are used. things are used. Suitable nonionic surfactants include, for example, compounds obtained by polymerizing and adding ethylene oxide to higher alcohols such as lauryl alcohol, stearyl alcohol, and oleyl alcohol; and compounds obtained by polymerizing and adding ethylene oxide to alkylphenols such as isooctylphenol and nonylphenol. Compounds in which ethylene oxide is polymerized and added to alkylnaphthols such as butylnaphthol and octylnaphthol; Compounds in which ethylene oxide is polymerized and added to higher fatty acids such as valmitic acid, stearic acid, and oleic acid; Higher fatty acid esters of polyhydric alcohols such as sorbitan; Compounds obtained by polymerizing and adding ethylene oxide to it; compounds obtained by block polymerizing and adding ethylene oxide and propylene oxide; and the like. Suitable anionic surfactants include, for example, alkyl sulfate salts such as sodium lauryl sulfate and oleyl alcohol sulfate amine salt; alkyl sulfonate salts such as sodium sulfosuccinate dioctyl ester and sodium 2-ethylhexene sulfonate. aryl sulfonates such as sodium isoglobilna-7talenes sulfonate, sodium methylene bisnaphthalene sulfonate, sodium lignosulfonate, and sodium dodecylbenzenesulfonate; Furthermore, the herbicide of the present invention may contain polymeric compounds such as casein, gelatin, albumin, glue, sodium alginate, carboxymethylcellulose, methylcellulose, hydroxyethylcellulose, polyvinyl alcohol, etc., for the purpose of improving the properties of the preparation and increasing the herbicidal effect. It is also possible to use adjuvants. The above-mentioned carriers and various auxiliary agents are used individually or in combination as appropriate, depending on the purpose, taking into account the dosage form of the preparation, the application situation, etc. The content of the active ingredient of the compound of the present invention (CI) in the various formulations thus obtained varies depending on the formulation, but is usually 0.1 to 99% by weight,
Preferably, 1 to 80% by weight is most suitable. In the case of a powder, for example, the active ingredient compound is usually contained in an amount of 1 to 25% by weight, and the remainder is a solid carrier, a surfactant, and the like. In the case of hydrating agents, for example, the active ingredient compound is usually 25 to 9
0%, the remainder being a solid carrier and a dispersion wetting agent,
A protective colloid, an antifoaming agent, etc. are added as necessary. In the case of granules, for example, the active ingredient compound is usually contained in an amount of 1 to 35% by weight, and the remainder is a solid carrier, a surfactant, and the like. Is the active ingredient compound homogeneously mixed with the solid carrier?
Alternatively, it is uniformly fixed or adsorbed on the surface of a solid carrier, and the particle diameter is about 0°2 to 1.5 m++w. In the case of an emulsion, for example, the grains contain 5 to 30% by weight of the active ingredient compound, this includes about 5 to 20% by weight of an emulsifier, and the remainder is a liquid carrier, with a spreading agent and a spreading agent as necessary. Rust inhibitors etc. are added. In the case of flowable agents, for example, the active ingredient compound is usually
~50% by weight, in addition to 3 to 10% by weight
The remainder is water, and a protective colloid, a preservative, an antifoaming agent, etc. are added as necessary. The 1,2,4-oxadiazole derivatives of the present invention can be used as herbicides as they are or in any formulation form as mentioned above. It can be applied to various weeds growing in rice fields and fields from the pre-emergence period to the growing season.The application amount is lh as the amount of the compound (effective amount) expressed by the general formula (1).
Approximately 0.05 to 5 kg per a, preferably O, l −
It weighs about 1 kg, and the target weed type, growth stage,
The selection can be changed as appropriate depending on the application location, application time, weather, etc. Next, several layers of formulation examples using the compounds of the present invention are shown. Note that "1 part" in the following formulation examples is based on weight. Formulation example 1 (granules) To compound N 4 5filS
Bentonite 50 parts Talc 40 parts Sodium dodecylbenzenesulfonate 2 parts Sodium ligninsulfonate 2 parts Polyoxyethylene alkylaryl ether After thoroughly mixing 1 part or more, add an appropriate amount of water, knead, and use a granulator. Granulation was carried out to obtain 100 parts of granules. Formulation example 2 (hydrating powder) Compound amount 7 20 parts diatomaceous earth 63 parts white carbon
15 parts and 2 or more parts of sodium dodecylbenzenesulfonate were mixed together and uniformly mixed and pulverized using a Ni-Goo to obtain 100 parts of a wettable powder. Formulation example 3 (emulsion) Compound amount 4 30 parts xylene 55 parts cyclohexanone 10 parts aryl ether
Emulsion 1 is obtained by uniformly mixing and dissolving two or more parts.
I got 00 copies. Formulation example 4 (flowable agent) Compound amount 4 30111S
Antifoaming agent 1 part propylene glycol 5 parts water
59 parts or more were uniformly ground and mixed in a wet ball mill to obtain 100 parts of a flowable agent. Herbicides using the compounds of the present invention can be formulated according to the formulation examples described above. Next, the effects of the herbicide of the present invention will be explained using test examples. Test Example 1 (Paddy soil treatment) A plastic pot with an area of 200 cm was filled with paddy soil mixed with an appropriate amount of chemical fertilizer, and paddy rice (variety: Nipponbare) that had been grown in a greenhouse and had reached the two-leaf stage was placed in it. 2 shares (
Two plants (one plant) were transplanted, and seeds of Japanese wildflower, Japanese azalea, Japanese cypress, and firefly were sown. Three days after paddy rice transplantation and sowing, each compound shown in Table 5 was prepared into a wettable powder according to Formulation Example 2, and diluted with an appropriate amount of water so that the active ingredient was 1 kg or 5 kg per 10 are.
It was added dropwise with a pipette. The herbicidal effect and the degree of chemical damage were investigated 25 days after the chemical treatment according to the following criteria. The results are shown in Table 5. Weeding effect Asakusa rate (asakusa rate relative to untreated area) 5
0 to less than 1%4 1% or more to 20% 3 20// to 401/ 2 401/ to 5 Q //1 60
1/ ~ 80/1 0 8ol/ ~I OON Level of drug damage No drug damage Very small amount of phytotoxicity Table 5 Prepared as a hydrating powder according to Formulation Example 2, containing 1 kg or 5 kg of active ingredient per 10 ares. It was diluted with an appropriate amount of water so that The herbicidal effect and the degree of chemical damage were investigated according to the standards of Test Example 1 25 days after the chemical treatment. The results are shown in Table 6. Test Example 2 (Paddy growing season treatment) Paddy rice (variety: Nipponbare) that had reached the two-leaf stage by filling a plastic pot with an area of 200 cm with paddy soil mixed with an appropriate amount of chemical fertilizer and growing it in a greenhouse in advance 2 shares (
Two plants (one plant) were transplanted, and seeds of Japanese wildflower, Japanese azalea, Japanese cypress, and firefly were sown. 1 After growing in a glass greenhouse at 20 to 25°C for 10 days after transplantation and sowing, each compound shown in Table 6 was added to Test Example 3 (Upland soil treatment) Square pots (30 x 30 x 12 cm) were filled with upland soil, and the results were as shown in Table 7. Seeds of various crops and weeds as shown were sown in fixed amounts and covered with 1 cra of soil. On the day after seeding, each compound shown in Table 7 was prepared into a wettable powder according to Formulation Example 2, and the active ingredient was 1 kg or 5
It was diluted with an appropriate amount of water to give a total weight of 1.0 kg and evenly spread over the soil surface. The herbicidal effect and the degree of chemical damage were investigated according to the standards of Test Example 1 25 days after the application of the drug. The results are shown in Table 7. Table 7

Claims (2)

[Claims] (1) General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼……(I) [However, R^1 and R^2 are either represented by a formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ and the other is an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an optionally substituted aryl group, where , X^1, X^2 are the same or different halogen atoms, R^3 is hydrogen, an alkyl group having 1 to 6 carbon atoms, and 1 to 6 carbon atoms.
haloalkyl group, alkenyl group having 2 to 4 carbon atoms, alkynyl group having 3 or 4 carbon atoms, optionally substituted aryl group, optionally substituted pyridyl group, alkoxycarbonylalkyl group having 3 to 6 carbon atoms, or carbon A 1,2,4-oxadiazole derivative represented by 2 to 6 hydroxycarbonyl alkyl groups. (2) General formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼……(I) [However, one of R^1 and R^2 is represented by a formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ and the other is an alkyl group having 1 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an optionally substituted aryl group, where , X^1, X^2 are the same or different halogen atoms, R^3 is hydrogen, an alkyl group having 1 to 6 carbon atoms, and 1 to 6 carbon atoms.
haloalkyl group, alkenyl group having 2 to 4 carbon atoms, alkynyl group having 3 or 4 carbon atoms, optionally substituted aryl group, optionally substituted pyridyl group, alkoxycarbonylalkyl group having 3 to 6 carbon atoms, or carbon A herbicide containing a 1,2,4-oxadiazole derivative represented by the following formula as an active ingredient.