WO2009014287A1

WO2009014287A1 - The composition for killing insects comprising azole compounds as an effective ingredient

Info

Publication number: WO2009014287A1
Application number: PCT/KR2007/006501
Authority: WO
Inventors: Young-Kook Kim; Kyeong Lee; Jung Joon Lee; Hyun-Sun Lee; Mun-Chual Rho; Yongseok Choi; Gyu Yong Song
Original assignee: Korea Research Institute Of Bioscience And Biotechnology
Priority date: 2007-07-26
Filing date: 2007-12-13
Publication date: 2009-01-29
Also published as: KR100836172B1

Abstract

The present invention relates to an insecticide composition containing the azole compound synthesized organic chemically as an active ingredient and a method for killing insects using the same. The azole compound of the present invention has the effect of spoiling appetite in larvae and excellent insecticidal activity, so that it can be used as a pro-environmental insecticide.

Description

[DESCRIPTION]

[invention Title]

THE COMPOSITION FOR KILLING INSECTS COMPRISING AZOLE COMPOUNDS AS AN EFFECTIVE INGREDIENT

[Technical Field]

The present invention relates to an insecticide composition comprising azole compounds as an active ingredient and a method for killing insects using the same.

[Background Art]

Agrichemical consumption is inevitable these days over the world to increase the productivity of agricultural crops by protecting them from damages by blight and harmfiαl insects. However, the remaining toxicity and environmental pollution resulted from the agrichemicals have caused many problems over the whole world. Thus, countries over the world agreed to reduce agrichemical consumption, especially highly toxic organic agrichemicals, not to harm human health. Specifically, they agreed to reduce gradually the consumption of the synthetic agrichemicals particularly harmful for human and livestock. In Korea, there was an agreement in 2004 to reduce 50% of the production of organophosphorous and organochlorine insecticides, the chemical insecticides which are neurotransmission inhibitors being used for about 10 years. And further the additional 50% reduction of the consumption of the organophosphorous and organochlorine insecticides until 2010 was agreed. In spite of all the efforts made by numbers of research teams from all over the world including those of multinational cooperations, a novel insecticide with new mechanism has not been developed, yet. If a safe insecticide is not developed, the above agreements will be in danger of breaching because of lack of agrichemicals, suggesting that the banned agrichemicals might have to be allowed to be consumed.

The inflow routes of the insecticides into living body are mouse, skin and stigma. Some insecticides flowing in the insect tissue are decomposed even before reaching the target area, so that they become non-toxic. But, other insecticides are, on the contrary, activated in vivo, so that they turn into more strong toxic materials, some of which are accumulated in organs and some of which are discharged. Even if the insecticide reaches the target area of insects, not all of them are involved in killing activity and some of the components cause non-specific reactions in the insect tissues. That is, only a part of the insecticide arrives at the target area to cause changes in biochemical functions for killing. Therefore, the target area, metabolic pathway and metabolism of insecticides are important factors considering the mechanism of insecticides.

The insecticides being used over the world can be classified according to their functions and mechanisms into neurotransmission inhibitors, energy production inhibitors, growth control inhibitors such as juvenile hormone inhibitors and chitin biosynthesis inhibitors and sex pheromone attractants. The insecticide developed as the sterol metabolism inhibitor by the present inventors made an addition. Most of the insecticides being used over the world are working on enzymes of nervous system or energy production system, the basic systems for life keeping of insects . Insects are killed suddenly by an abnormal stimulus given to nervous system such as excitation or suppression. Based on that, one of many kinds of insecticides has been designed to target the nervous system. Neuron is the minimum unit of nervous system, which is connected to dendrite of another neuron in axon terminal stretched from cell body. This connecting area is called synapse. A stimulus generated in nervous system is transmitted through axon to its end, presynaptic membrane. Right after, the chemical neurotransmitter released from synaptic vesicles, acetylcholine, moves to synapse and binds to the receptor in postsynaptic membrane to stimulate neuron. By this process, nerve stimulation is transmitted continuously to next neurons. Acetylcholine released from synaptic vesicles is responsible for transmitting stimulus from presynaptic membrane to postsynaptic membrane. After this mission, the acetylcholine is not necessary any more. To hydrolyze the acetylcholine, acetylcholine esterase is generated in postsynaptic membrane. The acetyl cholinesterase has two kinds of activities; one is degrading ester and anions, and the other is hydrolyzing acetylcholine. Acetylcholine finished its mission of transmitting nerve stimulation is accumulated in the receptor in postsynaptic membrane, which causes extreme excitation and convulsions. So, the accumulated acetylcholine is degraded into choline and acetic acid by acetylcholine esterase, which are absorbed in presynaptic membrane. The absorbed choline and acetic acid are changed into acetylcholine again in synaptic vesicles and then stored therein. Based on that, the insecticide acting as an acetylcholine esterase inhibitor is designed to inhibit the activity of acetylcholine esterase that is the enzyme decomposing the neurochemical transmitter, acetylcholine by the major constituents such as organophosphorous and carbamate compounds and thus acetylcholine is accumulated in synapse to cause troubles in neurotransmission system, which causes convulsions and paralysis, leading to the death of insects.

It is known that the organophosphorous and carbamate compounds are mainly working on the active site of acetylcholine esterase to inhibit the acetylcholine degradation activity of the enzyme. These compounds infiltrate fast through skin of the insect and are adhered on the surface of central nerve to cause abnormal neuronal actions. The abnormal symptoms are expressed as hypersensitivity, severe convulsion and paralysis to death after being through latent period.

There is another insecticide inhibiting composition of insect cuticle and chitin biosynthesis. Insects have to shed off the skin for gradual growth and thus cuticle biosynthesis is very important physiological function in insects. Insect skin is composed of cuticle, epidermis and basement membrane. Cuticle is composed of exocuticle and endocuticle. The endocuticle of the insect is N-acetyl glucosamine (chitin) polymer that contains a huge amount of chitin. Chitin is not found in vertebrates but a major component of insect cuticle. Therefore, if the chitin biosynthesis is inhibited by an inhibitor of shedding, the insect will be killed.

The mechanism of the inhibitor of shedding for insect larva is as follows; the inhibitor of shedding infiltrates through mouse and stigmas and then inhibits cuticle generation, making normal shedding impossible. At this time, this inhibitor only inhibits chitin formation in endocuticle without affecting the formation of exocuticle composed of hard protein. The precise mechanism of the inhibitor of shedding has not been disclosed, though. It is only known that the inhibitor of shedding inhibits chitin biosynthesis, which is the major component of endocuticle, by suppressing UDP-N-acetyl glucosamine polymerization.

Numbers of researchers have been tried to develop insecticides targeting the unique characteristics and functions of insects by inhibiting the generation of juvenile hormone and a substance causing mating disruption. Another attempt to kill insects i s to tempt male insects by using pheromone secreted by female insects. However, outdoor field test has demonstrated that this temptation is not so effective as to be commercialized. Many researchers have made molecular biological approach to understand insects and their physiological mechanisms and based on the studies on metabolic enzymes or receptors, they are trying to develop a novel insecticide. Larvae of insects take nutrients from outside and use them for growth. So, it can be another way to kill insects by inhibiting intake of food of larvae, suggesting that insecticide inhibiting diet of larvae is under development.

The present inventors completed this invention by confirming that the synthetic azole compound could spoil appetite in Plutella xylostella larvae and Myzus persicae imagoes and exhibited killing activity consistently and time-dependentIy.

[Disclosure]

[Technical Problem]

It is an object of the present invention to provide an effective insecticide targeting enzymes or receptors related in metabolism of insects via molecular biological approach.

[Technical Solution]

The present invention provides an insecticide composition containing the azole compound having the following structure and salts thereof as an active ingredient .

A is O or NR, and R is H or Ci-C₄ straight or side chain alkyl.

The present invention also provides a method for killing insects including the step of spraying or administering the effective dose of the above insecticide composition to insects.

The present invention further provides a use of the above azole compound and salts thereof for the production of the insecticide composition.

[Advantageous Effect]

The insecticide composition containing the synthetic azole compound of the present invention as an active ingredient shows excellent insect killing activity, so that it can be effectively used for the cultivation of crops as an insecticide.

[Description of Drawings]

The application of the preferred embodiments of the present invention is best understood with reference to the accompanying drawings, wherein:

Fig.l is a diagram showing the structure of 2-(4- Adamantan-1-yl-phenoxymethy) -benzooxazole-5-carboxylic acid (furan-2-ylmethyl) -amide, the azole compound of the present invention.

Fig.2 is a diagram showing the structure of 2- (4- Adamantan-1-yl-phenoxymethyl) -lH-benzoimidazole-5- carboxylic acid (furan-2-ylmethyl) -amide, the azole compound of the present invention.

[Best Mode]

Hereinafter, the present invention is described in detail.

[Formula l]

A is O or NR, and R is H or Ci-C₄ straight or side chain alkyl.

Preferably, the azole compounds 1 and 2 are organically synthesized by the methods of examples 1 and 2, but not always limited thereto. As mentioned, these examples are only examples of many production methods and the azole compound of the above formula can be synthesized by various methods known to those in the art, in addition to the synthesis by the below reaction formula.

The azole compound of the present invention exhibited consistent and time-dependent insect killing activity in the test with Plutella xylostella larvae and Myzus persicae imagoes. In the test, Plutella xylostella larvae and Myzus persicae imagoes also showed spoiled appetite. So, this compound is expected to be very effective in insect killing for the cultivation of agricultural crops and in protecting crops from harmful insects. The azole compound of the present invention targets larvae of harmful insects, acarids, nematodes, and greenhouse whiteflies. The harmful insect herein is selected from the group consisting of Plutella xylostella, Spodptera litura and Hyphantria cunea. The acarid herein is selected from the group consisting of Myzus persicae, Rhodobium porosum and Neotoxoptera formosana. The nematode herein is preferably selected from the group consisting of Meloidogyne incognita, Aphelenchoides besseyi and Hirschmanniella imamuri, but not always limited thereto.

The present invention also provides a use of the azole compound of the present invention or salts thereof for the production of the insecticide composition.

When the azole compound of the present invention is added to an insecticide as an active ingredient, it can be added as it is or as the form of a salt. The azole compound of the invention can be formulated into various forms by being mixed with general solid carriers, liquid carriers, gas carriers or baits or by being absorbed on basic substances such as porous ceramic plate or non-woven fabric. At this time, if necessary, surfactants and other supplements can be added thereto. The possible formulations are exemplified by oil spray, emulsified concentrate, moist powder, liquid, granule, dust, aerosol, smoke (ex. fogging), vaporizing preparation, smoking preparation, toxic bait, anti-acarid sheet or resin preparation .

The above formulations can contain the compound of the present invention as an active ingredient by 0.01.- 95 weight% . The solid carrier used for the above formulations includes micropowders or granules of clay such as kaolin clay, diatomaceous earth, bentonite and acid clay; talcs, ceramics and other inorganic substances such as sericite, quartz, sulfur, charcoal, calcium carbonate and hydrated silica; agrichemicals such as ammonium sulfate, ammonium phosphate, ammonium nitrate, urea and ammonium chloride.

The liquid carrier used for the above formulations includes water; alcohol such as methanol and ethanol; ketone such as acetone and ethyl ketone; aromatic hydrocarbon such as benzene, toluene, xylene, ethyl benzene and methyl naphthalene; aliphatic hydrocarbon such as hexane, cyclohexane, kerosene and light oil; ester such as ethyl acetate and butyl acetate; nitrile such as acetonitrile and idobutylnitrile; ether such as diisopropylether and dioxane; acid amide such as N, N- dimethylformamide and N, N-dimethylacetamide; halogenated hydrocarbon such as dichloromethane, trichloroethane and carbon tetrachloride; dimethylsulfoxide; and vegetable oil such as soybean oil and cotton seed oil. The gas carrier or propellant used for the above formulations includes Freon gas, butane gas, LPG (liquefied petroleum gas), dimethyl ether and carbon dioxide.

The basic substance used for the toxic bait is exemplified by inducement materials such as grain powder, vegetable oil, sugar and crystalline cellulose; antioxidant such as dibutylhydroxytoluene and nordihydroguairetic acid; preservative such as dihydroacetic acid; agents for preventing children from eating poisonous baits by mistake such as hot pepper powder; attractant flavor such as cheese flavor and onion flavor.

The surfactant herein can be selected from the group consisting of alkyl sulfate, alkyl sulfonate, alkyl aryl sulfonate, alkyl aryl ether and polyoxyethylene derivatives thereof, polyethylene glycol ether, polyvalent alcohol ester and sugar alcohol derivatives.

The supplements such as an adhesive or a dispersing agent includes casein; gelatin; polysaccharides such as starch, Arabia gum, cellulose derivatives and alginic acid; lignin derivatives; bentonite; sugar and synthetic soluble polymer such as polyvinyl alcohol, polyvinyl pyrrolidone and polyacrylic acid.

As a stabilizer, PAT (isopropyl acid phosphate), BHT

(2, β-di-tert-butyl-4-methylphenol) , BHA (mixture of 2-tert- butyl-4-methoxyphenol and 3-tert-butyl-4-methoxyphenol) , vegetable oil, mineral oil, surfactant, fatty acid and ester thereof can be included.

Agricultural insecticide, acaricide or nematocide comprising the azole compound of the present invention is preferably applied by 0.1-100 g per 10 acres. In the case of formulations diluted in water such as emulsifying concentrate, moist power, liquid and other similar preparations, the content of the azole compound of the present invention is preferably 1-1000 ppm. Such formulations as granule, dust or other similar preparations are used without being diluted. When the azole compound of the present invention is used as an insecticide, acaricide or nematocide for preventing an epidemic, emulsifying concentrate, moist powder, liquid or other similar preparations are diluted in water to adjust the concentration as 0.1-500 ppm. But, when the compound is formulated as the forms of oil spray, aerosol, smoke, toxic bait, anti-acarid sheet or other similar preparations, they are applied directly without being diluted. The amount of use and the concentration are different from types of formulations, time, place and method of application, kinds of harmful insects, expected damage and other factors. Therefore, the amount of use and concentration are not limited to the above and can be regulated properly.

If the azole compound of the present invention is used as insecticide or acaricide to control parasites of livestock such as cattle and pigs or pets such as cats and dogs, the azole compound of the invention or salts thereof can be formulated based on veterinary medicine. For phylogenetic control, tablets, capsules, extract solution, boli, suppositories or injections; or for non-phylogenetic control, molded products such as collar and ear tag (tag) can be prepared as insoluble or soluble spry solution and injection (pouring or dropping) . At this time, the azole compound of the present invention is preferably added by 0.01-100 mg per kg of a host.

The azole compound of the present invention can be used with other insecticides, acaricides, nematocides, bactericides, fungicides, herbicides, plant growth regulators, synergists, agrichemicals, earth conditioners and/or animal feeds at the same time or stepwise.

The present invention further provides a method for killing insects including the step of spraying or administering the effective dose of the insecticide composition of the present invention to insects.

The effective dose of the insecticide composition of the present invention is 0.001-95 weight%, but not always limited thereto and can be regulated properly by those in the art. [Mode for Invention]

Practical and presently preferred embodiments of the present invention are illustrative as shown in the following Examples. However, it will be appreciated that those skilled in the art, on consideration of this disclosure, may make modifications and improvements within the spirit and scope of the present invention.

Example 1: Synthesis of azole compound 1

2- ( 4-adamantane-l-yl-phenoxymethyl) -benzoxazole-5- carboxylic acid (30.1 mg, 0.08 mmol) , furfurylamine (11.0 mg, 0.12 mmol, 0.01 ml), EDC (21.7 mg, 0.12 mmol) and HOBt (15.4 mg, 0.12 mmol) were added into 3.0 mL of DMF, to which DIPEA (14.2 mg, 0.12 mmol, 0.02 ml) was added. After stirring, the organic layer was separated with EtoAC and 10% HCl. The organic layer was washed with sodium chloride solution, dried over anhydride MgSC>₄ and concentrated. Purification was performed by silica gel column chromatography (π-Hexane: EtOAc: MeOH=6: 3 : 1) to give the target compound as a white solid (32.9 mg, yield: 90.9%). The structure of the compound is as follows.

[Formula 2]

2- (4-Adamantan-l-yl-phenoxymethy) -benzooxazole-5- carboxylic acid (furan-2-ylmethyl) -amide

¹H-NMR (CDCl₃, 300 Hz) 8.15 (¹H, m, aromatic-H) , 7.86 7.89 (¹H, m, aromatic-H), 7.59 (¹H, d, J = 8.7 Hz, aromatic-H), 7.39 (¹H, m, aromatic-H), 7.28 7.31 (²H, m, aromatic-H), 6.99 7.01 (²H, m, aromatic-H), 6.42 (¹H, s, NH), 6.32 6.37 (²H, m, aromatic-H), 5.31 (²H, s, CH₂), 4.67 (²H, d, J = 5.7 Hz, CH₂), 2.08 (³H, m, adamantly-H) , 1.87 (⁶H, m, adamantly-H), 1.76 (⁶H, m, adamantly-H).

Example 2 : Synthesis of azole compound 2 2- (4-adamantane-l-yl-phenoxymethyl) -IH- benzoimidazole-5-carboxylic acid (50 mg, 0.124 mmol) , furfurylamine (18 mg, 0.186 mmol) and DMAP (22.78 mg, 0.186 mmol) were added into 1.0 mL of DMF, to which PyBOP (97 mg, 0.186 mmol) was added at room temperature. After stirring at room temperature, 150 ml of water was added thereto. The generated solid was extracted with MeOH:MC (10%) and washed with sodium chloride solution, sodium hydrogen carbonate solution and water. The product was dried over anhydride MgSθ₄ and concentrated. Purification was performed by PLC (MeOHrMC=O .5 : 9.5) to give the target compound as a colorless solid (43.2 mg, yield: 72%) .

[Formula 3]

2- (4-Adamantan-l-yl-phenoxymethyl) -lH-benzoimidazole- 5-carboxylic acid (furan-2-ylmethyl) -amide

¹H NMR (CDCl₃, 300 MHz) 8.08 (¹H, s, CONH), 7.59 (¹H, d, J = 8.4 Hz, furan) , 7.46 (¹H, d, J = 8.7 Hz, furan) , 7.29 (¹H, s, aromatic), 7.15 (²H, d, J = 8.4 Hz, aromatic), 7.07 (¹H, m, furan), 6.79 (²H, d, J = 8.4 Hz, aromatic), 6.24 (²H, d, J =12.3 Hz, aromatic), 5.21 (²H, s, OCH₂), 4.59 (²H, d, J = 4.8 Hz, furan-CH₂NH), 2.02 (³H, s, adamantyl), 1.76-1.65 (¹²H, m, adamantyl), benzoimidazole NH not detected.

Experimental Example 1: Insecticidal activity test with Plutella xylostella L. larva

Plutella xylostella L. was used as the test insect of the present invention and the insecticidal activity was tested at the Department of Agricultural Biology, Collage of Agriculture, Life & Environment Science, Chungbuk National University, Cheongju, Chungcheongbuk-Do, Korea, in September, 2006. The azole compounds 1 and 2 having insecticidal activity were weighed precisely and 10 mg of each compound was dissolved in proper amount of acetone (10 mg/10 ml) . The acetone containing the compound was mixed with 100 ppm triton X-100 solution 9 times the volume of the acetone, followed by serial dilution (1:10, 1:100, and 1:1000) to prepare test solutions. As for the feeds for Plutella xylostella L. larvae, cabbage leaves in even growth condition were cut into disks (3.0 cm in diameter), which were fully sunk in the prepared test solution for 30 seconds. The cabbage leaf disks were taken out and dried in a hood for 60 minutes. The test solution treated cabbage leaf disks were distributed on a petridish (55^χ20 mm) covered with the wet filter paper. Second larvae of Plutella xylostella L. were moved by a soft brush not to be damaged, leading to the inoculation three times, 10 larvae at a time. The larvae treated with the sample were raised in a constant temperature room (25 ± 1^°C, relative humidity: 40-45%, 16L:8D) and death rate was investigated on hour 24 and 48. As for the non-treated group, the leaves were treated with 10% acetone solution mixed with 100 ppm triton X-IOO solution 9 times the volume of the acetone solution by the same manner as described in the above method for treating the sample. The activity test was repeated three times. And the results are shown in Table 1.

As shown in Table 1, different concentrations of the azole compounds 1 and 2 (1, 10, and 100 ppm) were treated to Plutella xylostella L. larvae and killing activity was measured at 1 day interval. The experimental group exhibited consistent and time dependent insecticidal activity, compared with the control. The larvae treated with the compounds 1 and 2 exhibited spoiled appetite by avoiding feeds at high concentration, unlike the control.

[Table 1]

Insecticidal activity of the azole compounds 1 and 2 on Plutella xylostella L. larva

Experimental Example 2: Insecticidal activity test with Myzus persicae imagoes

Myzus persicae was used as the test insect of the present invention and the insecticidal activity was tested at the Department of Agricultural Biology, Collage of Agriculture, Life & Environment Science, Chungbuk National University, Cheongju, Chungcheongbuk-Do, Korea, in September, 2006. The azole compounds 1 and 2 having insecticidal activity were weighed precisely and 10 mg of each compound was dissolved in proper amount of acetone (10 mg/10 ml) . The acetone containing the compound was mixed with 100 ppm triton X-100 solution 9 times the volume of the acetone, followed by serial dilution (1:10, 1:100, and 1:1000) to prepare test solutions. The Myzus persicae imagoes treated with the sample were raised in a constant temperature room (25 - 28 ^°C, relative humidity: 50 - 60%, 16L:8D) and death rate was investigated on hour 24 and 48. As for the non-treated group, the Myzus persicae imagoes were treated with 10% acetone solution mixed with 100 ppm triton X-100 solution 9 times the volume of the acetone solution by the same manner as described in the above method for treating the sample. The test sample insecticides were diluted at different concentrations, in which cabbage leaf disks (5 cm in diameter) was sunk for 30 seconds. The disks were dried in shadow. The dried cabbage leaf disks were placed on a disposable petri-dish (5.5 * 2 cm) covered with cotton and a filter paper (Φ5.5 cm). The Myzas persicae imagoes were placed on the dish by 10 insects. The dish was treated with the screening solution prepared above. After treatment, death rate was investigated 1, 2, and 3 days later. The experiment was repeated three times. The experiment conditions were same as the proposed above.

As shown in Table 2, different concentrations of the azole compounds 1 and 2 (1, 10, and 100 ppm) were treated to Myzus persicae imagoes and killing activity was observed everyday for three days. As a result, the experimental group exhibited consistent, time-dependent insecticidal effect, compared with the control . The imagoes treated with the compounds 1 and 2 exhibited spoiled appetite by avoiding feeds at high concentration, unlike the control.

[Table 2]

Insecticidal activity of the azole compounds 1 and 2 on Myzus persicae imagoes

Those skilled in the art will appreciate that the conceptions and specific embodiments disclosed in the foregoing description may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. Those skilled in the art will also appreciate that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended claims .

Claims

[CLAIMS]

[Claim l]

An insecticide composition containing the azole compound having the structure represented by formula 1 or salts thereof as an active ingredient:

A is O or NR, and R is H or Ci~C₄ straight or side chain alkyl.

[Claim 2]

The insecticide composition according to claim 1, wherein the insecticide is targeting larvae of harmful insects, acarids and nematodes.

[Claim 3]

The insecticide composition according to claim 2, wherein the harmful insect is selected from the group consisting of Plutella xylostella, Spodptera litura and Hyphantria cunea.

[Claim 4] The insecticide composition according to claim 2, wherein the acarid is selected from the group consisting of Myzus persicae, Rhodobium porosum and Neotoxoptera formosana. The

[Claim 5]

The insecticide composition according to claim 2, wherein the nematode is selected from the group consisting of Meloidogyne incognita, Aphelenchoides besseyi and Hirschmanniella imamuri.

[Claim β]

A method for killing insects including the step of treating the effective dose of the insecticide composition of claim 1 to insects or their habitats.

[Claim 7]

The method for killing insects according to claim 6, wherein the treatment to insects is spraying or administration.

[Claim 8]

A use of the azole compound or salts thereof of claim 1 for the production of an insecticide composition.