JP7478561B2 - Rodent repellent and method for repelling rodents - Google Patents

Description

The present invention relates to a rodent repellent and a rodent repelling method that contain a specific alkyl phenyl sulfide derivative compound as an active ingredient.

Traditionally, problems caused by wild rodents have resulted in livelihood and economic losses, such as damage to crops caused by rodents invading farmland, accidents caused by rodents invading roads and railways, damage caused by rodents invading houses and warehouses, and damage caused by rodents biting electric wires and communication cable networks. In particular, damage amounting to 689 million yen occurred in the agricultural sector in fiscal 2012 (see non-patent document 1).

For this reason, repellents for protecting objects from rodents have been actively developed for many years. For example, Patent Document 1 describes products such as rodent-proof electric wires and cables and rodent-proof paints that utilize the high repellent effect of capsaicins against rats, Patent Document 2 describes a cable that uses cycloheximide and capsaicin to exert a repellent effect, and Patent Document 3 describes a garbage bag that uses denatonium benzoate, capsaicin, or the like to exert a repellent effect. However, capsaicins have problems in that they are expensive and highly irritating to the human body, making them difficult to handle, and cycloheximide can be harmful to the human body through skin contact, so there is a risk of problems if the active ingredient is exposed to the surface of an item that humans may come into contact with in everyday life. In addition, denatonium benzoate is water-soluble and dissolves in environments with a lot of moisture, so there is a problem with the duration of its effect.

Patent No. 3053480 JP 2000-348542 A Japanese Patent Application Laid-Open No. 9-169401

Status of damage to crops caused by wild birds and animals (2012) (Ministry of Agriculture, Forestry and Fisheries)

The object of the present invention is to provide a repellent that is easy to handle and has an excellent repellent effect against rodents, and a method for repelling rodents.

Under these circumstances, the inventors have investigated various compounds and found that a specific alkyl phenyl sulfide derivative has excellent repellent activity against rodents and is easy to handle, which led to the present invention. That is, the present invention is as follows.

（式中、ｎは０～２の整数を示し、Ｒ_１はハロゲン原子またはＣ_１～Ｃ_６アルキル基を示し、Ｒ_２はハロゲン原子またはＣ_１～Ｃ_６アルキル基を示し、Ｒ_３はＣ_１～Ｃ_６アルキル基（該基はＲ_４によりモノ置換又はポリ置換されてもよい）、フェニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）、ピリジル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）またはピリミジニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）を示し、Ｒ_４はＣ_１～Ｃ_６ハロアルキルチオ基またはフェニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）を示し、Ｒ_５はハロゲン原子またはＣ_１～Ｃ_６ハロアルキル基を示す。）
（２）前記アルキルフェニルスルフィド誘導体が、下記式［Ｉａ］で表される化合物である前記（１）に記載のネズミ目動物忌避剤。

（式中、Ｒ_１、Ｒ_２及びＲ_４は前記式［Ｉ］と同じ意味を示し、Ｒ_３１はＣ_１～Ｃ_６アルキレン基を示す。）
（３）前記アルキルフェニルスルフィド誘導体が、下記式［Ｉ－１］で表される化合物である前記（１）または（２）に記載のネズミ目動物忌避剤。

（４）前記（１）～（３）のいずれかに記載のネズミ目動物忌避剤を、ネズミ目動物を忌避したい場所またはその周辺に配置することを特徴とする、ネズミ目動物の忌避方法。
（５）前記ネズミ目動物忌避剤を飼料に混合して、ネズミ目動物を忌避したい場所またはその周辺に配置する、前記（４）に記載のネズミ目動物の忌避方法。
(1) A rodent repellent comprising, as an active ingredient, one or more compounds selected from the group consisting of alkyl phenyl sulfide derivatives represented by the following formula [I] and agriculturally acceptable salts thereof:

(wherein n represents an integer of 0 to 2, R ₁ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₂ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₃ represents a C ₁ -C ₆ alkyl group (which may be mono- or poly-substituted with R ₄ ), a phenyl group (which may be mono- or poly-substituted with R ₅ ), a pyridyl group (which may be mono- or poly-substituted with R ₅ ) or a pyrimidinyl group (which may be mono- or poly-substituted with R ₅ ), R ₄ represents a C ₁ -C ₆ haloalkylthio group or a phenyl group (which may be mono- or poly-substituted with R ₅ ), and R ₅ represents a halogen atom or a C ₁ -C ₆ haloalkyl group.)
(2) The rodent repellent according to (1) above, wherein the alkyl phenyl sulfide derivative is a compound represented by the following formula [Ia]:

(In the formula, R ₁ , R ₂ and R ₄ are the same as defined in the formula [I], and R ₃₁ is a C ₁ -C ₆ alkylene group.)
(3) The rodent repellent according to (1) or (2), wherein the alkyl phenyl sulfide derivative is a compound represented by the following formula [I-1]:

( 4 ) A method for repelling rodents, comprising placing the rodent repellent according to any one of (1) to ( 3 ) above in or around a place where rodents are desired to be repelled.
( 5 ) The rodent repelling method according to ( 4 ) above, which comprises mixing the rodent repellent with feed and placing the feed in or around a place where rodents are to be repelled.

The repellent of the present invention exhibits excellent repellent activity against rodents, is less irritating to the human body, and is easy to handle. Therefore, by using the repellent of the present invention, damage caused by rodents can be easily prevented.

FIG. 1 is a diagram showing an overview of the repellency test device used in Test Example 1.

The rodent repellent and rodent repellent method of the present invention exert sufficient repellent activity even at low doses, achieves repellent effect quickly, and has a long-lasting repellent effect, so that by incorporating the repellent of the present invention, damage caused by rodents can be prevented. The present invention will be described in detail below.

（式中、ｎは０～２の整数を示し、Ｒ_１はハロゲン原子またはＣ_１～Ｃ_６アルキル基を示し、Ｒ_２はハロゲン原子またはＣ_１～Ｃ_６アルキル基を示し、Ｒ_３はＣ_１～Ｃ_６アルキル基（該基はＲ_４によりモノ置換又はポリ置換されてもよい）、フェニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）、ピリジル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）またはピリミジニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）を示し、Ｒ_４はＣ_１～Ｃ_６ハロアルキルチオ基またはフェニル基（該基はＲ_５によりモノ置換又はポリ置換されてもよい）を示し、Ｒ_５はハロゲン原子またはＣ_１～Ｃ_６ハロアルキル基を示す。） The rodent repellent of the present invention contains, as an active ingredient, one or more compounds selected from the group of compounds consisting of alkyl phenyl sulfide derivatives represented by the following formula [I] and agriculturally acceptable salts thereof.

(wherein n represents an integer of 0 to 2, R ₁ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₂ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₃ represents a C ₁ -C ₆ alkyl group (which may be mono- or poly-substituted with R ₄ ), a phenyl group (which may be mono- or poly-substituted with R ₅ ), a pyridyl group (which may be mono- or poly-substituted with R ₅ ) or a pyrimidinyl group (which may be mono- or poly-substituted with R ₅ ), R ₄ represents a C ₁ -C ₆ haloalkylthio group or a phenyl group (which may be mono- or poly-substituted with R ₅ ), and R ₅ represents a halogen atom or a C ₁ -C ₆ haloalkyl group.)

The above symbols and terms used in this specification are explained below.

In the present invention, a halogen atom refers to a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

In the present invention, the notation such as C ₁ to C ₆ indicates the number of carbon atoms of the following substituent, and in this case indicates that the number of carbon atoms is 1 to 6.

In the present invention, unless otherwise specified, the C ₁ -C ₆ alkyl group means a linear or branched alkyl group having 1 to 6 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an n-hexyl group, and the like.

In the present invention, unless otherwise specified, the C ₁ -C ₆ haloalkyl group means a linear or branched haloalkyl group having 1 to 6 carbon atoms substituted with 1 to 13 identical or different halogen atoms, and examples thereof include fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, bromomethyl, dibromomethyl, tribromomethyl, iodomethyl, chlorodifluoromethyl, dichlorofluoromethyl, and the like.

In the present invention, unless otherwise specified, the C ₁ -C ₆ haloalkylthio group refers to a (C ₁ -C ₆ haloalkyl)-S- group in which the haloalkyl portion has the above meaning, and examples thereof include fluoromethylthio, difluoromethylthio, trifluoromethylthio, trichloromethylthio, etc.

In the present invention, unless otherwise specified, the C ₁ -C ₆ alkylene group means a linear or branched alkylene group having 1 to 6 carbon atoms, and examples thereof include a methylene group, an ethylene group, a propylene group, a propane-2,2-diyl group, a butylene group, an isobutylene group, and a hexylene group.

（式中、Ｒ_１、Ｒ_２及びＲ_４は前記式［Ｉ］と同じ意味を示し、Ｒ_３１はＣ_１～Ｃ_６アルキレン基を示す。）、
又は、下記式［Ｉｂ］

（式中、Ｒ_５は前記式［Ｉ］と同じ意味を示し、ｍは１または２の整数を示し、Ｌは単結合または炭素数１～６のアルキレン基を示し、Ｒ_３２は２価または３価のベンゼン環又はピリジン環を示す。）
で表される化合物を挙げることができる。 Suitable examples of the alkyl phenyl sulfide derivative represented by the above formula [I] include those represented by the following formula [Ia]:

(In the formula, R ₁ , R ₂ and R ₄ are the same as defined in the formula [I], and R ₃₁ is a C ₁ -C ₆ alkylene group.)
Or the following formula [Ib]

(In the formula, _R5 has the same meaning as in formula [I], m is an integer of 1 or 2, L is a single bond or an alkylene group having 1 to 6 carbon atoms, and _R32 is a divalent or trivalent benzene ring or pyridine ring.)
Examples of the compound include those represented by the following formula:

Further, specific examples of the alkyl phenyl sulfide derivative represented by the above formula [I] include the following compounds represented by the following formulas [I-1], [I-2], [I-3], [I-4] and [I-5].

In the following description, one or more compounds selected from the group of compounds consisting of alkyl phenyl sulfide derivatives represented by the above formula [I] and agriculturally acceptable salts thereof will be referred to as "the compound."

These compounds are all known compounds described in JP 2015-160813 A and can be produced in accordance with the method described in that publication.

The present compound has a repellent effect against rodents. Using this as an active ingredient includes not only the case where the present compound is the only repellent, but also the case where other known repellents are contained. Examples of such other known repellents include p-cymene, gamma-terpinene, hexyl acetate, terpineol, essential oil components such as orange oil, rosemary oil, camphor, and peppermint oil, boric acid, capsaicin, cycloheximide, and denatonium benzoate. The amount of the other repellent is preferably an amount that does not cause problems when the resulting rodent repellent comes into contact with humans.

On the other hand, the rodent repellent of the present invention can contain additives that are typically used in pesticide formulations, if necessary.

These additive components include carriers such as solid or liquid carriers, surfactants, binders, tackifiers, thickeners, colorants, spreading agents, adhesives, antifreeze agents, anticaking agents, disintegrants, antidegradants, polymeric materials, etc.

If necessary, preservatives, plant fragments, etc. may be added as additives. These additives may be used alone or in combination of two or more. These additives are described below.

Examples of solid carriers include natural minerals such as quartz, clay, kaolinite, pyrophyllite, sericite, talc, bentonite, acid clay, attapulgite, zeolite, and diatomaceous earth; inorganic salts such as calcium carbonate, ammonium sulfate, sodium sulfate, and potassium chloride; organic solid carriers such as synthetic silicic acid, synthetic silicates, starch, cellulose, and plant powder; and plastic carriers such as polyethylene, polypropylene, and polyvinylidene chloride.

Examples of liquid carriers include monohydric alcohols such as methanol, ethanol, propanol, isopropanol, and butanol; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, and glycerin; polyhydric alcohol derivatives such as propylene glycol ethers; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone; ethers such as ethyl ether, dioxane, cellosolve, dipropyl ether, and tetrahydrofuran; normal paraffin, naphthene, sulfoparaffin, Examples of such compounds include aliphatic hydrocarbons such as kerosene and mineral oil; aromatic hydrocarbons such as benzene, toluene, xylene, solvent naphtha, and alkylnaphthalene; halogenated hydrocarbons such as dichloroethane, chloroform, and carbon tetrachloride; esters such as ethyl acetate, diisopropyl phthalate, dibutyl phthalate, dioctyl phthalate, and dimethyl adipate; lactones such as γ-butyrolactone; amides such as dimethylformamide, diethylformamide, dimethylacetamide, and N-alkylpyrrolidinone; nitriles such as acetonitrile; sulfur compounds such as dimethyl sulfoxide; vegetable oils such as soybean oil, rapeseed oil, cottonseed oil, and castor oil; and water.

The surfactant is not particularly limited, but is preferably one that gels in water or exhibits swelling properties. For example, non-ionic surfactants such as sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, sucrose fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene resin acid esters, polyoxyethylene fatty acid diesters, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene dialkyl phenyl ethers, polyoxyethylene alkyl phenyl ether formalin condensates, polyoxyethylene polyoxypropylene block polymers, alkyl polyoxyethylene polypropylene block polymer ethers, polyoxyethylene alkylamines, polyoxyethylene fatty acid amides, polyoxyalkylene-added acetylene diols, polyoxyethylene ether-type silicones, ester-type silicones, fluorine-based surfactants, polyoxyethylene castor oil, and polyoxyethylene hydrogenated castor oil; alkyl sulfates, polyoxyethylene alkyl ether sulfates, polyoxyethylene Anionic surfactants such as alkyl phenyl ether sulfate, polyoxyethylene styryl phenyl ether sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl phenyl ether sulfate, polyoxyethylene styryl phenyl ether sulfate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, salt of formalin condensate of naphthalene sulfonic acid, salt of formalin condensate of alkyl naphthalene sulfonic acid, fatty acid salt, polycarboxylate, N-methyl-fatty acid sarcosinate, resin acid salt, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkyl phenyl ether phosphate; cationic surfactants such as alkyl amine salts such as laurylamine hydrochloride, stearylamine hydrochloride, stearylaminopropylamine acetate, alkyl trimethyl ammonium chloride, alkyl dimethyl benzalkonium chloride; amphoteric surfactants such as amino acid type, betaine type, imidazoline type, etc.

Examples of binders and tackifiers include carboxymethylcellulose and its salts, dextrin, water-soluble starch, xanthan gum, guar gum, sucrose, polyvinylpyrrolidone, gum arabic, polyvinyl alcohol, polyvinyl acetate, sodium polyacrylate, polyethylene glycol with an average molecular weight of 6,000 to 20,000, polyethylene oxide with an average molecular weight of 100,000 to 5,000,000, and natural phospholipids.

Examples of thickeners include xanthan gum, guar gum, carboxymethylcellulose, polyvinylpyrrolidone, carboxyvinyl polymers, acrylic polymers, starch derivatives, water-soluble polymers such as polysaccharides, high-purity bentonite, and inorganic fine powders such as white carbon.

Colorants include, for example, inorganic pigments such as iron oxide, titanium oxide, and Prussian blue, and organic dyes such as alizarin dyes, azo dyes, and metal phthalocyanine dyes.

Examples of spreading agents include silicone surfactants, cellulose powder, dextrin, modified starch, polyaminocarboxylic acid chelate compounds, cross-linked polyvinylpyrrolidone, maleic acid and styrenes, methacrylic acid copolymers, half esters of polyhydric alcohol polymers and dicarboxylic acid anhydrides, and water-soluble salts of polystyrene sulfonic acid.

Examples of spreading agents include surfactants such as sodium dialkyl sulfosuccinate, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, and polyoxyethylene fatty acid esters; paraffin; terpene; polyamide resins; polyacrylates; polyoxyethylene; wax; polyvinyl alkyl ethers; alkylphenol-formaldehyde condensates; and synthetic resin emulsions.

Examples of antifreeze agents include polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, and glycerin.

Examples of anti-caking agents include polysaccharides such as starch, alginic acid, mannose, and galactose, polyvinylpyrrolidone, white carbon, ester gum, and petroleum resins.

Examples of disintegrants include sodium tripolyphosphate, sodium hexametaphosphate, metal stearates, cellulose powder, dextrin, methacrylic acid ester copolymers, polyvinylpyrrolidone, polyaminocarboxylic acid chelate compounds, sulfonated styrene-isobutylene-maleic anhydride copolymers, and starch-polyacrylonitrile graft copolymers.

Examples of decomposition inhibitors include desiccants such as zeolite, quicklime, and magnesium oxide; antioxidants such as phenols, amines, sulfur, and phosphoric acid; and ultraviolet absorbers such as salicylic acid and benzophenone.

There are no particular limitations on the polymeric material as long as it does not lose its effect as a repellent according to the present invention. For example, rubber-based materials such as silicone rubber, acrylic rubber, guar gum, locust bean gum, natural rubber, urethane rubber, ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), and styrene-butadiene rubber (SBR, SEBR, etc.); polyvinyl alkyl ether, polyvinyl alcohol, polyvinyl acetate, methyl vinyl ether/maleic anhydride copolymer, polyvinyl pyrrolidone, carboxyl vinyl polymer, vinyl pyrrolidone/vinyl acetate alkylamino acrylic acid copolymer, metacarboxy betaine/metacarboxy ester copolymer, styrene/maleic acid copolymer, ethylene/vinyl acetate copolymer, partially saponified ethylene/vinyl acetate copolymer, Examples of such materials include synthetic polymers such as cellulose copolymers, partially saponified polyvinyl acetate, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyacetal, polyphenylene sulfide, polyimide, polyether ketone, polyetherimide, polyether ether ketone, polyacrylonitrile, poly(meth)acrylic acid alkyl esters, and polyalkylene oxides; and natural polymer materials such as chitin, chitosan, starch, collagen, pullulan, ethyl cellulose, methyl cellulose, cellulose acetate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose phthalate, and carboxymethyl cellulose.

Preservatives include, for example, potassium sorbate and 1,2-benzthiazolin-3-one.

Examples of plant fragments include sawdust, coconut husks, corn cobs, tobacco stalks, etc.

The rodent repellent of the present invention can be produced by mixing the present compound with, if necessary, other known repellents as described above, at least one of the above-mentioned additive components, such as an inert liquid carrier and/or solid carrier, and further at least one surfactant.

The rodent repellent of the present invention produced as described above may be formulated and used in any form, such as liquid, emulsion, wettable powder, wettable granule, dust, oil, flowable, granule, tablet, jumbo, suspoemulsion, microcapsule, paste, seed coating agent, fumigant, smoke agent, bean crush (registered trademark) agent, gelling agent, propellant, vulcanizing agent, sheet agent, etc. These formulations can be prepared by commonly used known methods using additives commonly used in formulations in the fields of pharmaceuticals, agricultural chemicals, food, etc. Examples of such additives include the additive components described above.

The compound can also be impregnated into or supported on a porous material. Examples of porous materials include zeolite, porous silica, cellulose, heat-moisture treated starch, cyclodextrin, polyurethane foam, and expanded polystyrene. The compound can also be impregnated into, coated on, or laminated onto other substrates such as nonwoven fabric, rock wool, urethane foam, paper, cotton, felt, rope, and netting.

The compound can also be used as a paint composition. There is no particular limit to the paints into which the compound can be mixed. For example, when classified by raw materials, there are oil-based paints, alcohol paints, cellulose paints, synthetic resin paints, water-based paints, lacquer-based paints, and rubber-based paints. Oil-based paints include boiled oil, oil paint, oil varnish, and enamel. Alcohol-based paints include natural resin varnish and synthetic resin varnish. Cellulose paints include clear lacquer and lacquer enamel. Synthetic resin paints include water-based paint varnish, synthetic resin enamel, and emulsion polymerization paint. Water-based paints include water-based paints, emulsion oil paint, and emulsion polymerization paint. Lacquer-based paints include lacquer and cashew varnish. Rubber-based paints include chlorinated rubber paints and synthetic rubber paints such as SBR.

The rodent repellent of the present invention can be used in various forms as described above. The concentration of the present compound contained in each form can be appropriately determined depending on the type of rodent to be repellent, the location where it is placed, the temperature, the formulation of the rodent repellent of the present invention, and the like. For example, the concentration of the present compound in the formulation can be in the range of 0.0001 to 100% by mass, preferably 0.0001 to 50% by mass, more preferably 0.001 to 30% by mass, and most preferably 0.02 to 10% by mass.

The rodent repellent of the present invention may be applied by coating or other methods to components that require a repellent effect, such as cables, wiring, garbage bags, etc., or may be incorporated into materials that require a repellent effect, such as the covering material for cables or wiring, or the synthetic resin of garbage bags, during production to impart a repellent effect to the components themselves.

The rodent repellent of the present invention may further contain additives such as insect repellents, insecticides, bactericides, fungicides, fragrances, and colorants, if necessary.

The rodent repellent of the present invention is effective against rodents that cause damage to agricultural crops, forests, livestock, electric wires, etc., and rodents that invade houses, warehouses, etc. and eat food.

Rodents are animals also called rodents or rodents, and examples include rodents such as jerboas, mole rats, crucian hamsters, water voles, voles, brown rats, brown rats, house mice, Japanese field mice, Japanese house mice, field mice, Japanese field mice, Japanese bank mice, gerbils, and African giant mice; beavers and other rodents; dormice and other dormants; sciuromorphs and other squirrels; and hystrix and other squirrels.

By placing the rodent repellent of the present invention, it is possible to reduce damage caused by rodents in the area where it is placed and in the surrounding space.

Places where the rodent repellent of the present invention can be placed include, for example, fields, orchards, forests, livestock farms, roads, highways, railways, airports, garbage dumps, dust collection areas, parks, gardens, flower beds, parking lots, buildings, warehouses, houses, kitchens, washrooms, balconies, storerooms, under floors, utility poles, electric wires, communication cables, wire mesh, fences, etc.

The rodent repellent of the present invention can be applied to a location where rodents are to be repelled or in the vicinity thereof, and is not particularly limited. The rodent repellent of the present invention can be applied by simply placing the rodent repellent, or by known methods such as scattering, spraying, or painting.

In the rodent repelling method of the present invention, the rodent repellent of the present invention may be mixed with feed in advance and placed in or around a location where rodents are to be repelled. In this case, for example, the rodent repellent may be mixed in an amount of 0.0001 to 100% by mass, preferably 0.0001 to 50% by mass, more preferably 0.001 to 30% by mass, and most preferably 0.02 to 10% by mass relative to the feed.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Test examples show that this compound has excellent repellent activity against rodents. The compounds used in the test examples are shown in Table 1. The compound used in Example 1 was synthesized by the method described in JP 2015-160813 A. The capsaicin used in Comparative Example 1 was purchased from FUJIFILM Wako Pure Chemical Corporation. The compound used in Comparative Example 2 was synthesized by the method described in JP 2017-036251 A.

Test Example 1 (Test Animal: House Mouse)
<Test Equipment>
The repellency test was carried out using the repellency test apparatus shown in FIG. 1. The apparatus was a modified Y-maze ("YM-03M (for mice)" manufactured by Muromachi Kikai Co., Ltd.), and had two arms, each 300 mm long and 40 mm wide, connected to two feeding spaces in a space with a running path length of 100 mm and a running path width of 100 mm, which served as the living area. Test area 1 and test area 2 were arranged with food placed at both ends. The walls were uniformly 100 mm high and had a ceiling opening of 100 mm. The top was covered with an iron net to prevent escape. Palsoft (registered trademark, manufactured by Oriental Yeast Co., Ltd.) was laid on the bottom of the living area as a bedding. A water supply container was inserted above the living area, and water was freely available during the test period.

<Acclimation procedure>
Prior to the repellency test, an acclimatization procedure was carried out to familiarize the test animals with the test apparatus.
Approximately 40 g (initial weight of food) of measured weight of food (MS powdered food, Oriental Yeast Co., Ltd.) was placed in each of test areas 1 and 2, and one male mouse was placed in the living area. The weight of food remaining in both test areas was measured every 24 hours, and the amount of food consumed each day was calculated. The food was replaced with new food every 3 or 4 days, and the mice were allowed to acclimate for several days.

<Repellency test>
After the habituation procedure was completed, about 40 g of basal feed (MS powder feed, manufactured by Oriental Yeast Co., Ltd.) and mixed feed prepared by mixing each compound of the Examples and Comparative Examples in Table 1 so that the compound concentration in the feed was the mass % shown in Table 2 were placed in each test group. The mass of the feed remaining in each test group was measured every 24 hours, and the feed intake for each day was calculated. The feed was replaced with new feed every 3 or 4 days.

The repellent effect of each compound was calculated from the amount of food consumed each day using the following formula (1) to give a repellent rate, which is shown in Table 2. Table 2 also shows the workability when handling the compound.
Repellency rate (%) = 100 x (cumulative basal feed intake - cumulative mixed feed intake) / (cumulative basal feed intake + cumulative mixed feed intake) ... (1)

The capsaicin in Example 1 exerted a long-term, high repellent effect on mice even at a low dose. The capsaicin in Comparative Example 1 also exerted a long-term, high repellent effect, but was highly irritating to the skin and eyes, and therefore required sufficient protection to prevent scattering and adhesion, making the work complicated.

Claims (5)

A rodent repellent comprising, as an active ingredient, one or more compounds selected from the group consisting of alkyl phenyl sulfide derivatives represented by the following formula [I] and agriculturally acceptable salts thereof:

(wherein n represents an integer of 0 to 2, R ₁ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₂ represents a halogen atom or a C ₁ -C ₆ alkyl group, R ₃ represents a C ₁ -C ₆ alkyl group (which may be mono- or poly-substituted with R ₄ ), a phenyl group (which may be mono- or poly-substituted with R ₅ ), a pyridyl group (which may be mono- or poly-substituted with R ₅ ) or a pyrimidinyl group (which may be mono- or poly-substituted with R ₅ ), R ₄ represents a C ₁ -C ₆ haloalkylthio group or a phenyl group (which may be mono- or poly-substituted with R ₅ ), and R ₅ represents a halogen atom or a C ₁ -C ₆ haloalkyl group.) 2. The rodent repellent according to claim 1, wherein the alkyl phenyl sulfide derivative is a compound represented by the following formula [Ia]:

(In the formula, R ₁ , R ₂ and R ₄ are the same as defined in the formula [I], and R ₃₁ is a C ₁ -C ₆ alkylene group.) The rodent repellent according to claim 1 or 2, wherein the alkyl phenyl sulfide derivative is a compound represented by the following formula [I-1]:

A method for repelling rodents, comprising placing the rodent repellent according to any one of claims 1 to 3 in or around a place where rodents are to be repelled. 5. The method of claim 4 , wherein the rodent repellent is mixed with food and placed at or near a location where rodents are desired to be repelled.

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