JP5039375B2 - Isothiazole compounds and plant disease control agents for agriculture and horticulture - Google Patents

Description

  The present invention relates to an isothiazole compound or a salt thereof, and an agricultural and horticultural plant disease control agent comprising the same as an active ingredient.

A certain type of isothiazole compound is known, for example, in Patent Document 1, and its use as an agricultural and horticultural fungicide is disclosed, but the isothiazole compound of the present invention is not described in the document.
JP 2005-82486 A

  In the cultivation of agricultural and horticultural crops, many control agents are used against crop diseases. However, conventional control agents may have insufficient control efficacy, may be restricted in their use due to the emergence of drug-resistant pathogens, and may cause phytotoxicity or contamination of plants, Or, from the viewpoint of toxicity to human and livestock fish and the impact on the environment, there are many things that are not necessarily satisfactory control agents. Accordingly, there is a strong demand for the emergence of a control agent that can be safely used with few such drawbacks.

  An object of the present invention is to solve the above-mentioned problems that conventional plant disease control agents have, and to provide a plant disease control agent which is further excellent in control effect, residual effect and the like.

  In order to achieve the above-mentioned object, the present inventors have synthesized a large number of isothiazole compounds that have not been known to have plant disease control activity so far, and have intensively studied their plant disease control activity and usefulness. As a result, by applying the isothiazole compound of the present invention (hereinafter referred to as the compound of the present invention) to plants, plant diseases can be controlled over a long period of time, and remarkable plant diseases can be controlled without causing phytotoxicity to plants. The inventors have found that the present invention is effective and have completed the present invention.

  That is, the present invention relates to the following (1) to (3).

(1) Formula [I]

[Wherein, Q ¹ and Q ² each independently represent a chlorine atom or a bromine atom. ]
An isothiazole compound represented by the formula:

(2) The isothiazole compound or a salt thereof according to (1), wherein Q ¹ and Q ² in formula [I] are chlorine atoms.

(3) A plant disease control agent for agricultural and horticultural use comprising the isothiazole compound or salt thereof according to (1) or (2) as an active ingredient.

  Next, specific examples of the compound of the present invention represented by the formula [I] are shown in Table 1. However, the compound of the present invention is not limited to these compounds. The compound number is referred to in the following description.

  Although the typical manufacturing method of this invention compound represented by a formula [I] is illustrated below, the manufacturing method of this invention compound is not limited to these.

(Wherein Q ¹ and Q ² have the same meaning as described above, and L represents a halogen atom such as a chlorine atom or a bromine atom.)

  The compound represented by the formula [III] can be produced by reacting the compound represented by the formula [II] with a halogenating reagent in a solvent or in the absence of a solvent.

  Examples of the halogenating reagent that can be used in this step include acid chlorides such as oxalyl chloride and thionyl chloride. If necessary, an amide such as N, N-dimethylformamide (DMF) may be added in a catalytic amount.

  What is necessary is just to select the usage-amount of a halogenating reagent from the range of 1-100 mol suitably with respect to 1 mol of compounds represented by Formula [II], Preferably it is 1-5 mol.

  The solvent that can be used in this step is not particularly limited as long as it does not inhibit the progress of this reaction. For example, ethers such as diethyl ether, tetrahydrofuran, dioxane, monoglyme, diglyme; dichloromethane, chloroform, carbon tetrachloride, dichloroethane, etc. Halogenated hydrocarbons; aromatic hydrocarbons such as benzene, chlorobenzene, nitrobenzene, and toluene; nitriles such as acetonitrile can be used, and a mixed solvent thereof can also be used.

  The usage-amount of a solvent is 0-100 liter with respect to 1 mol of compounds represented by Formula [II], Preferably it is 0-2.0 liter.

  What is necessary is just to select reaction temperature from the range of the boiling point range of the inert solvent used from -20 degreeC, It is good to carry out in the range of 0 to 100 degreeC preferably.

  The reaction time varies depending on the reaction temperature, reaction substrate, reaction amount, etc., but is usually 30 minutes to 10 hours.

  The compound represented by the formula [III], which is the target product of this step, is collected from the reaction system by a conventional method after completion of the reaction. The obtained target product can be purified by operations such as column chromatography and recrystallization as necessary.

  The compound of the present invention represented by the formula [I] can be produced by reacting the compound represented by the formula [III] with a reducing agent in a solvent or in the absence of a solvent.

  Examples of the reducing agent that can be used in this step include borohydride compounds such as sodium borohydride.

  What is necessary is just to select the usage-amount of a reducing agent from the range of 1-100 mol suitably with respect to 1 mol of compounds represented by Formula [III], Preferably it is 1-5 mol.

  The solvent that can be used in this step is not particularly limited as long as it does not inhibit the progress of this reaction. For example, ethers such as diethyl ether, tetrahydrofuran, dioxane, monoglyme, diglyme; methanol, ethanol, propanol, isopropanol, butanol, tert Alcohols such as butanol; water; halogenated hydrocarbons such as dichloromethane, chloroform, carbon tetrachloride and dichloroethane; aromatic hydrocarbons such as benzene, chlorobenzene, nitrobenzene and toluene; N, N-dimethylformamide, N, Amides such as N-dimethylacetamide; Ureas such as 1,3-dimethyl-2-imidazolinone; Sulfur compounds such as dimethyl sulfoxide; Nitriles such as acetonitrile can be used. It can also be used.

  The amount of the solvent used is 0 to 100 liters, preferably 0.1 to 5.0 liters, per 1 mol of the compound represented by the formula [III].

  What is necessary is just to select reaction temperature from the range of the boiling point range of the inert solvent used from -20 degreeC, It is good to carry out in the range of 0 to 50 degreeC preferably.

  The reaction time varies depending on the reaction temperature, reaction substrate, reaction amount and the like, but is usually 10 minutes to 10 hours.

  The compound of the present invention represented by the formula [I], which is the target of the reaction, is collected from the reaction system by a conventional method after completion of the reaction. The obtained target product can be purified by operations such as column chromatography and recrystallization as necessary.

  The plant disease control agent for agricultural and horticultural use of the present invention comprises an isothiazole compound represented by the formula [I] or a salt thereof as an active ingredient.

  Examples of the salt of the isothiazole compound include inorganic salts such as hydrogen chloride, hydrogen bromide and sulfuric acid, organic salts such as oxalic acid, acetic acid and citric acid, alkali metal salts such as sodium and potassium, calcium and the like. And alkaline earth metal salts.

  When the compound of the present invention is used as an agricultural / horticultural plant disease control agent, it may be used alone, but the active ingredient can be used in an appropriate dosage form depending on the purpose.

  Usually, the active ingredient is diluted with an inert liquid or solid carrier, and if necessary, a surfactant or the like is added thereto, and it can be used in the form of a powder, wettable powder, emulsion, granule or the like. The blending ratio of the active ingredient is appropriately selected as necessary, but 0.1 to 50% (weight) when used as a powder and granule, and 5 to 80% (weight) when used as an emulsion and wettable powder. Is appropriate.

  Examples of carriers used for formulation include talc, bentonite, clay, kaolin, diatomaceous earth, white carbon, vermiculite, calcium carbonate, slaked lime, silica sand, ammonium sulfate, urea and other solid carriers, isopropyl alcohol, xylene, cyclohexane, cyclohexanone, methyl Examples thereof include liquid carriers such as naphthalene.

  Surfactants and dispersants include, for example, alkylbenzene sulfonic acid metal salts, dinaphthylmethane disulfonic acid metal salts, alcohol sulfate esters, alkylaryl sulfonates, lignin sulfonates, polyoxyethylene glycol ethers, polyoxyethylene alkyls. Examples thereof include aryl ethers and polyoxyethylene sorbitan monoalkylates. Examples of the auxiliary agent include carboxymethyl cellulose, polyethylene glycol, gum arabic and the like.

  Furthermore, the agricultural and horticultural plant disease control agent of the present invention includes, in addition to the compound of the present invention, which is an active ingredient, in the various preparation forms described above, other known active compounds such as insecticides, You may mix with a mite, an insect growth regulator, a nematicide, a fungicide, a plant disease control agent, a herbicide, a plant growth regulator, a safener, a fertilizer, or a soil conditioner.

Examples of the fungicide compound that may be mixed are shown below.
Amisulbrom, benomyl, benthiavalicarb, benopirad ethaboxam, bitertanol, blastcidin-S, boscalid, captan (Captan), carbendazol, carpropamid, chlorothalonil, cyazofamid, cyflufenamid, cymoxanil, diclomezine, dimoxystrobin, dimoxystrobin dithianon, edifenphos, fenamidone, fenarimol, fenbuconazole, fluazinam, fluopicolide, fluoxastrobin (fluoxast) robin), flutolanil, folpet, fosetyl, fthalide, guazatine, hexaconazole, hydroxyisoxazole, hymexazol, iprobenphos (Iprobenfos), iprodione, iprovalicarb, isoprothiolane, isotianil, kasugamycin, mandipropamid, maneb, mepanipyme, n (Metalaxyl), metrafenone, microbutanyl, orysastrobin, oxadixyl, oxolinic acid, pefurazoate, pefurazoate, Cyclone (pencycuron), phenazine oxide, picoxystrobin, polycarbamate, polyoxin, probenazole, prochloraz, procymidone, propamocarb hydrochloride (procymidone) propamocarb, propiconazole, propineb, proquinazid, proquinazid, pyraclostrobin, pyribencarb, pyroquilon, simeconazole, streptomycin, tecloftram ), Thiabendazole, thiophanate-methyl, thiuram, tiadinil, tolnifanide, triadimefon, Rishikurazoru (tricyclazole), trifloxystrobin (trifloxystrobin), triflumizole (triflumizole), triforine (triforine), validamycin (validamycin), vinclozolin (vinchlozoline), zineb (zineb), ziram (ziram)

Examples of pesticide compounds that may be mixed.
Acetamiprid, clothianidin, dinotefuran, imidacloprid, nitenpyram, thiacloprid, thiamethoxam, thiamethoxam, ethiprole, protoprol , Chromafenozide, halofenozide, methoxyfenozide, tebufenozide, acrinathrin, allethrin, alpha-cypermethrin, beta-cyfluthrin (beta) ), Beta-cypermethrin, bifenthrin, bioallethrin, bioresmethrin, cycloprothrin Cyfluthrin, cyhalothrin, cypermethrin, cyphenothrin, deltamethrin, empenthrin, esfenvalerate, fenpropathrin, fenvalerate ), Flucythrinate, flumethrin, gamma-cyhalothrin, imiprothrin, lambda-cyhalothrin, methothrin, permethrin, phenothrin ), Prarethrin, resmethrin, kadesthrin, tau-fluvalinate, teflutrin, tetramethrin, zeta cypermetry Zeta-cypermethrin, tralomethrin, transfluthrin, etofenprox, halfenprox, silafluofen, bensultap, cartap, thiocyclam ( thiocyclam), thiosultap-sodium, acephate, azamethiphos, azinphos-ethyl, azinphos-methyl, cadusafos, chlorethoxyfos, Chlorfenvinphos, chlormephos, chlorpyrifos, chlorpyrifos-methyl, coumaphos, cyanophos, demeton-S-methyl, Daiji Dizinon, dichlorvos, dicrotophos, dimethoate, dimethylvinphos, disulfoton, EPN, ethion, etoprophos, famphur, fenamiphos (Fenamiphos), fenitrothion, fenthion, fosthiazate, heptenophos, isocarbophos, isoxathion, malathion, mecarbam, memidamphos, methamiphos, methamiphos (Methidathion), mevinphos, monocrotophos, nared, omethoate, oxydemeton-methyl, parathion, parathion me Parathion-methyl, phenthoate, phorate, phosalone, phosmet, phosphamidon, phoxim, pirimiphos-methyl, profenofos ( profenofos, propetamphos, prothiofos, pyraclofos, pyridaphenthion, quinalphos, sulfotep, tebupirimfos, temephos, temephos, tersfos Chlorvinphos, thiometon, triazophos, trichlorfon, bamidothion, imicyafos, flupyrazofos, aldicarb, bendiocal Bendiocarb, benfuracarb, carbaryl, carbofuran, carbofuran, carbosulfan, ethiofencarb, fenobucarb, formethanate, furathiocarb, isoprocarb ), Methiocarb, methomyl, metolcarb, oxamyl, pirimicarb, propoxur, trimethacarb, XMC (XMC), xylylcarb, alanycarb ), Butocarboxim, butoxycarboxim, thiodicarb, thiofanox, bistrifluron, chlorfluazuron , Diflubenzuron, flucycloxuron, flufenoxuron, hexaflumuron, lufenuron, novaluron, noviflumuron, teflubenzuron, flufluururon ), Triflumuron, abamectin, emamectin, emamectin, chlorfenapyr, phenoxycarb, hydroprene, kinoprene, metoprene, pyriproxyfen , Dienochlor, cyenopyrafen, cyflumetofen, spiromesifen, spirodiclofen, spirotetramat, fulvenge Flubendiamide, flurimfen, flonicamid, metaflumizon, linaxypyr, lepmectin, pyridalyl, fluacrypyrim, oxab , Bromopropylate, triazamate, fenazaquin, fenpyroximate, pyridaben, tebufenpyrad, clofentezine, etoxazole, hexathazox, hexythiazox Pymetrozine, buprofezin, 1.3 dichloropropene (1.3-D), isocarbophos, ammonium N-methyldithiocarbamate (NCS), azosi Rotin (endocyclotin), endosulfan, chlordane, chloropicrin, cyhexatin, spinosad, sodium dimethyldithiocarbamate, fenbutatin oxide , Flusulfamide, methyl isothiocyanate (MITC), rotenone, bioallethrin S-cyclopentenyl isomer, CL-900187, cryolite, NNI-0101, RU-15525, XDE-175, ZXI 8901

  These compounds are listed in The Pesticide Manual, 13th edition (British Crop Protection Council, 2004), Shibuya Index 10th edition, 11th edition (SHIBUYA INDEX 10th Edition, 11th Edition, Publisher: SHIBUYA INDEX Study Group) or publicly known.

  The plant disease control agent for agricultural and horticultural use according to the present invention can be used by spraying these leaves as they are or by diluting them, spraying seeds, applying seeds, applying soil, applying water or raising seedling boxes. These application rates vary depending on the type of compound used, target disease, occurrence tendency, degree of damage, environmental conditions, dosage form used, and the like.

  For example, when using it as it is like a powder agent and a granule, it is good to select suitably from the range of 0.1g-5kg per 10 are, preferably 1g-1kg with an active ingredient.

  Further, when used in a liquid form such as an emulsion and a wettable powder, it is suitably selected from the range of 0.1 ppm to 10,000 ppm, preferably 10 to 3,000 ppm.

  Moreover, when using by seedling box application, it is possible to provide a long-term effect by formulating the compound with controlled dissolution.

  The plant disease control agent for agricultural and horticultural use of the present invention can control plant diseases caused by filamentous fungi, bacteria and viruses by the above-mentioned application form.

Next, specific diseases are given as non-limiting examples.
Cucumber downy mildew (Pseudoperonospora cubensis), apple black spot disease (Venturia inaequalis), cucumber powdery mildew (Sphaerotheca cucurbitae), wheat powdery mildew (Erysiphe graminis), wheat blight fungus (Septoria nodorum), rice blast ore yz (Pyricularia) ), Cucumber gray mold (Botrytis cinerea), rice rot (Rhizoctonia solani), wheat rust (Puccinia recondita), cucumber spot bacterial disease (Pseudomonas syringe), rice white leaf blight (Xanthomonas oryzae), rice blast Diseases (Burkholderia glumae), rice seedling bacterial disease (Burkholderia plantarii), rice brown disease (Acidovorax avenae), inner bud browning disease (Erwinia ananas), cucumber anthracnose (Colletotrichum orbiculare)

  The plant disease control agent for agricultural and horticultural use of the present invention has a high control effect against rice blast, rice blight, wheat blight, wheat powdery mildew, cucumber downy mildew, cucumber anthracnose, etc. Moreover, since it has the characteristics of excellent residual effect and rain resistance without causing phytotoxicity to crops, it is useful as an agricultural and horticultural plant disease control agent.

  Hereinafter, the production method, formulation method and use of the compound of the present invention represented by the formula [I] used in the agricultural and horticultural plant disease control agent of the present invention will be described in detail in the following examples. There are no restrictions on the examples. In the following description, “%” indicates “weight percentage”.

  First, the production method of the compound of the present invention will be specifically described with reference to examples.

[Example 1]
Production of 3,4-dichloroisothiazole-5-methanol (Compound No. 1)
Oxalyl chloride (50 ml) and a catalytic amount of DMF were added to 3,4-dichloroisothiazole-5-carboxylic acid (50 g, 253 mmol), and the mixture was stirred at 50 ° C. for 30 minutes. The reaction mixture was concentrated under reduced pressure, and the residue was distilled under reduced pressure to give 3,4-dichloroisothiazole-5-carboxylic acid chloride as colorless crystals (50.4 g; boiling point: 55-60 ° C./0.5 mmHg). Melting point: 25-27 ° C .; yield 92%).

Sodium borohydride (1.9 g, 50.5 mmol) was suspended in water (40 ml), and 3,4-dichloroisothiazole-5-carboxylic acid chloride (4.3 g) prepared above was suspended in this suspension. , 19.9 mmol) in THF (4 ml) was added dropwise at 10-15 ° C. After stirring at 15 ° C. for 30 minutes, citric acid aqueous solution was added to make it weakly acidic, and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous magnesium sulfate and concentrated. The obtained crystals were washed with hexane to obtain 3,4-dichloroisothiazole-5-methanol (3.0 g) as colorless crystals (melting point 94-95 ° C.) (yield 82%).
¹ H-NMR (CDCl ₃ ) δ: 2.28 (1H, bs), 4.96 (2H, s) ppm

  Next, the preparation method will be specifically described with reference to typical preparation examples. The types and compounding ratios of the compounds and auxiliary agents are not limited to these and can be changed in a wide range. In the following description, “part” means “part by weight”.

[Formulation Example 1] Powder Powder 2 parts of Compound No. 1, 5 parts of diatomaceous earth and 93 parts of clay were uniformly mixed and ground to obtain a powder. In addition, powders could be obtained in the same manner using each of the compounds shown in Table 1 instead of Compound No. 1.

[Formulation Example 2] Wettable powder 50 parts of Compound No. 1, 45 parts of diatomaceous earth, 2 parts of sodium dinaphthylmethane disulfonate and 3 parts of sodium ligninsulfonate were uniformly mixed and ground to obtain a wettable powder. Further, a wettable powder could be obtained in the same manner using each of the compounds shown in Table 1 instead of Compound No. 1.

[Formulation Example 3] Emulsion 30 parts of the compound of Compound No. 1, 20 parts of cyclohexanone, 11 parts of polyoxyethylene alkylaryl ether, 4 parts of calcium alkylbenzenesulfonate and 35 parts of methylnaphthalene were uniformly dissolved to prepare an emulsion. Further, in place of Compound No. 1, an emulsion could be obtained in the same manner using each of the compounds shown in Table 1.

[Formulation Example 4] Granule 24 parts of Compound No. 1, 2 parts of sodium salt of lauryl alcohol sulfate, 5 parts of sodium lignin sulfonate, 2 parts of carboxymethyl cellulose and 67 parts of clay were uniformly mixed and ground. This mixture was kneaded by adding an amount equivalent to 20% water, processed into a 14-32 mesh granule using an extrusion granulator, and dried to give granules. Moreover, it replaced with the compound number 1 and was able to obtain a granule similarly using each compound of Table 1.

  Next, the effects of the agricultural / horticultural plant disease control agent of the present invention will be specifically described with reference to test examples.

[Test Example 1] Cucumber Anthracnose Prevention Effect Test Four cucumber seeds (variety: Sagamihanjiro) were sown at a seeding depth of 2 cm in a plastic cup having a diameter of 5.5 cm and grown in a greenhouse for 7 days. The wettable powder prepared according to Formulation Example 2 was diluted with water so that the active ingredient concentrations were 1 ppm and 10 ppm, and a spreading agent (Kumiten) was added so that the dilution ratio was 3000 times. Into the roots of the cucumber seedlings in which the cotyledons were developed, 10 ml of each cup was soil irrigated. Seven days later, cucumber plants were uniformly spray-inoculated by hand spraying with a conidial spore suspension (10 ⁵ to 10 ⁶ / ml) of cucumber anthracnose fungus (Colletotrichum orbiculare) cultured on a PDA plate medium at 25 ° C. For 24 hours. Then, it left still on the water board in a glass greenhouse, and after 6 days, the number of lesions of the cotyledon of the whole pot was investigated, the control value was calculated | required by the formula shown as number 1 below, and the result was shown in Table 2.

  In addition, the comparative compound in a table | surface is the compound number 1 described in Unexamined-Japanese-Patent No. 2005-82486, and has the following structures.

Test Example 2 Rice Blast Disease Water Surface Application Test Three 1.5-stem paddy rice seedlings (variety: Aichi Asahi) were transplanted into four places at 9 places in a white porcelain bowl having a diameter of 9 cm and grown in a greenhouse. At the 2.5 leaf stage, the wettable powder prepared according to Formulation Example 2 was applied to the surface of the pot so that the active ingredient concentration was 100 g and 10 g per 10 ares. Ten days after the treatment, a conidial spore suspension of rice blast fungus (Pyricularia oryzae) was spray-inoculated and immediately placed in a humid chamber at 25 ° C. for 24 hours. Then, it moved to a greenhouse and investigated the number of lesions on the highest leaf at the time of inoculation 5 days after the inoculation. The control value was calculated | required with the formula shown below as number 2, and the result was shown in Table 3.

(Equation 2)
Control value (%) = (1−number of lesions in treated area / number of lesions in untreated area) × 100

  In addition, the comparative compound in a table | surface is the said compound of the compound number 1 described in Unexamined-Japanese-Patent No. 2005-82486.

Claims (3)

Formula [I]

[Wherein, Q ¹ and Q ² each independently represent a chlorine atom or a bromine atom. ]
An isothiazole compound represented by the formula: The isothiazole compound or a salt thereof according to claim ^1, wherein Q ¹ and Q ² in formula [I] are chlorine atoms.   A plant disease control agent for agricultural and horticultural use comprising the isothiazole compound or salt thereof according to claim 1 or 2 as an active ingredient.