JP3123727B2 - Pine wood nematode control agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agent for controlling pine wood nematodes, particularly a pine wood nematode repellent and insecticide containing substances contained in Taiwanese horsetail pine, strobe pine and rhubarb pine, and hydroxystilbenes. The present invention relates to a method for synthesizing hydroxystilbenes.

[0002]

2. Description of the Related Art It is well known that pine wood nematodes, which are fungiphagous nematodes, invade and propagate in the pine wood tissue, causing pine to die. The mechanism of pine wilt by the pine wood nematode is considered as follows. a) Toxin (phytoalexin) such as (1) benzoic acid, (2) catechol, (3) dihydroconiferyl alcohol, (4) 8-
(5) Production of substances such as hydroxycarbontanacetone, (5) 10-hydroxyverbenone, b) Secretion of cellulase by nematodes, c) Temporary vessels of pine by α-pinene and β-pinene which are abnormally accumulated after nematode infection D) secretion of toxins by filamentous fungi growing in pine trees after nematode infection. It is known that the transmission of the pine wood nematode to the pine is carried out by pests such as pine wood beetles.

Conventional control measures against pine wilt caused by pine wilt mainly include (1) eggs in the damaged pine until the beetle holding the nematode, which directly causes pine wilt, escapes from the damaged tree. And (2) insecticide spraying methods (ground spraying and aerial spraying) to prevent post-eating after escaping and emergence of mantis. Here, as the insecticides used for spraying, organic phosphorus agents, NAC agents (1-naphthyl-N-methylcarbamate), PAP agents (dimethyldithiophosphorylphenylacetate), EDB agents (1,2-dibromoethyl),
MPP agent (O, O-dimethyl-O- [3-methyl-4-
(Methylthio) phenyl] thiophosphate) and ME
P agent (dimethyl (3-methyl-4-nitrophenyl) thiophosphate) and the like. In addition to the above pine weevil control agents, levamisole hydrochloride containing levamisole hydrochloride as the main insecticidal component (trade names: Century, Mitsubishi Yuka) as an insecticide for directly controlling nematodes in wood Co., Ltd.), a mesurfenphos agent (trade name: Nemanone, manufactured by Nippon Special Agrochemical Manufacturing Co., Ltd.), and a morantel tartrate agent (trade name: Glingard, Taisu Pfizer Co., Ltd.).

[0004]

The conventional methods for controlling pine wilt insects require (1) a great deal of labor, and (2) the time of emergence of the horny insects varies from year to year. (3) The effectiveness of the drug is decreasing, (4) In order to increase the control effect in forests, the dosage per unit area is 1
(5) There are problems such as social problems such as residual soil, water system residues, and effects on living organisms such as surrounding animals and plants. Not been. (6) Conventional nematicides that directly control nematodes in wood are effective but toxic,
There is a problem in terms of safety. Until now, it has not been known that organic solvent extracts or extract compounds from pine and hydroxystilbenes are effective as pine wood nematode control agents.

[0005]

The present inventors have conducted intensive studies on the control of pine wood nematodes.
The fact that there are substances that have repellent or lethal activity against pine wood nematodes in strobe pine or rhubarb pine, and that they have no problem in terms of safety, and that hydroxystilbenes are effective in controlling pine wood nematodes They have found that they are effective and have reached the present invention. That is, the present invention provides (1) a pine wood nematode controlling agent containing an organic solvent extract of pine, (2) a pine wood nematode repellent containing α-humulene, or a mixture of α-humulene and β-visaborene, (3) A pine wood nematode repellent containing a mixture of α-pinene and caralene; (4) a pine wood nematode containing methyl ferulate, (+)-pinoresinol or a mixture thereof; (5) hydroxy A pine wood nematocide containing stilbenes and salts thereof, (6)
A methoxystilbene is synthesized from a benzylphosphonate and a methoxybenzaldehyde by a Wittig-Horner reaction, and then demethylated with a demethylating agent to obtain a hydroxystilbene. And a method for producing a salt thereof.

Organic solvents for extracting the active ingredient from pine include alcohols, esters, hydrocarbons, halogenated hydrocarbons, aromatic hydrocarbons, ethers, ketones and the like. The method of extracting an active ingredient from pine with an organic solvent is as shown in FIG. Pine branches are finely chopped, immersed in methyl alcohol for about 1 to 3 months at a temperature of room temperature to 55 ° C., then filtered, and the methyl alcohol solution fraction is shaken with pentane, and the pentane solution fraction and the methyl alcohol solution are mixed. Separate into fractions. The methyl alcohol solution fraction is concentrated and freeze-dried to obtain a nonvolatile component.
This non-volatile component was a solid having a viscous brown-wood odor. On the other hand, the pentane solution fraction was concentrated to obtain a volatile component. This volatile component is a brown oil,
[Α] _D ²⁵ −6.0 ° ( c = 5.9, CHCl ₃ ). The non-volatile components extracted from methyl alcohol are further processed as described later. Next, Table 1 shows the lethal activity and resistance of the non-volatile components to the pine wood nematode. In addition, all the lethal activity test methods were performed according to the following methods. 1) Approximately 300 proliferating pine wood nematodes cultured on the Botrytis cinerea flora were placed in a counting petri dish (5.5 cm in diameter). 2) The test solution has a sample concentration of 1000 ppm, 100 p
pm, 10 ppm and appropriately 10 ppm or less (Tables 9 to 1)
It was prepared by dissolving it in a 2% aqueous ethanol solution as described in 2). 3) 4 ml of the test solution was injected into a petri dish containing the above nematodes. As a control solution, a 2% aqueous ethanol solution in which the sample was not dissolved was used. 4) The test solution was allowed to stand in the dark at 10 ° C., and the number of moving nematodes was counted under a stereoscopic microscope every 24 hours for 3 days to determine the survival rate. The test was repeated five times for each test solution under the same conditions, and the average value was determined to be the average survival rate. At this time, the average survival rate of the nematode in the control test solution was 99.5% and the standard error ± 3% at each measurement. 5) The lethal activity was indicated by relative mortality. The relative mortality was determined according to the following equation.

[0007]

(Equation 1)

[0008] In addition, the resistance is based on the “forest pest and animal damage control technology” 3
21 pages (1981) (published by the National Association of Forest, Pest and Animal Disease Control)
The data described in was used.

[0009]

[Table 1]

From Table 1, it is clear that there are lethal active substances against pine wood nematodes in strobe pine, rhubarb pine, Taiwanese horsetail pine, Echinata pine, loblolly pine and slash pine. Next, the above-mentioned non-volatile components were further tested for pine wood nematode lethal activity of the four types of fractions obtained from the bark of the strobe pine and the heartwood according to the operation steps shown in FIG. The test method was as described above. The results are as shown in Table 2. It can be seen that the lethal active ingredient is mainly contained in the fractions of the pine heartwood portion that are soluble in chloroform, the portion that is soluble in ethyl acetate, and the portion that is soluble in butanol.

[0011]

[Table 2]

Next, the stove pine core was treated in accordance with the operation process shown in FIG. 3 to obtain an ethyl acetate-soluble part and a butanol-soluble part. The ethyl acetate-soluble portion was subjected to silica gel column chromatography to obtain active fractions A-1 and A-2. On the other hand, the butanol-soluble part was subjected to gel filtration chromatography, silica gel chromatography, and then preparative high performance liquid chromatography to obtain pinosylvin monomethyl ether represented by the following formula.

[0013]

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Further, lethality of the methyl ferulate, (+)-pinoresinol and pinosylvin monomethyl ether and the pesticide Century (trade name, Mitsubishi Yuka Co., Ltd.) of the present invention obtained from Taiwanese horsetail pine by the method described below. An activity test was performed. The test method was as described above. Table 3 shows the results.

[0015]

[Table 3]

The lethal activity of binosylvin monomethyl ether and a substance having a structure similar thereto is shown in Table 4.

[0017]

[Table 4]

In the pine wood nematode controlling agent containing these extracts, the content of the extract components is 1 to 2%.
And used by mixing with other known carriers. The repellent active ingredient α-humulene of the present invention is present in the essential material of the horsetail pine, and the essential material of the horsetail pine is an organic solvent such as alcohols.
It is obtained by extraction with esters, hydrocarbons, halogenated hydrocarbons, aromatic hydrocarbons, ethers and ketones. This α-humulene has a repellent activity against the dispersed pine wood nematode as shown in Table 5. The repellent activity test method will be described later. The repellent of the present invention contains 1 to 2% of an α-humulene component, and is used by being mixed with other known carriers. Further, a composition containing α-humulene and β-bisabolene can enhance the repellent activity. The content of β-bisabolene may be arbitrary, but is preferably about 30 to 50% based on α-humulene. or,
Among other terpene hydrocarbons other than α-humulene, those having repellent activity against pine wood nematodes include α-pinene and caralene. Still further, a mixture of terpene hydrocarbons exhibiting nematode repellent activity can be obtained, for example, by the following method. Taiwanese horsetail pine heartwood (13 kg) is processed by the method shown in FIG.
The volatile component (14 g) was obtained, and the volatile component was repeatedly subjected to silica gel chromatography to obtain a mixture I (1.1 g) of two terpene hydrocarbons showing nematode repellent activity [α-humulene (60%) + β -Bisabolene (40%)] and mixture II (1.5 g) [α-pinene (60%) + calalene (40%)]. The compound exhibiting the above repellent activity is represented by the following formula.

[0019]

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The pine wood nematode repellent activity test of these terpene hydrocarbons is shown below. The repellent activity test against pine wood nematodes (Tables 5 and 6) was carried out by a test method for inducing activity against pine wood nematodes (T-tube method) [Watanabe Hiroyasu, Chemistry and Biology, 20 , 123 (198)
2)] was partially modified. That is, in the Watanabe method, a sample is absorbed by boiling stone, and the vapor of the sample is diffused by sending air to the surface of the boiling stone. In the present invention, the sample vapor was diffused by previously dissolving the sample in an aqueous solution of a surfactant (0.1% Triton X-100) and blowing purified air through an activated carbon filter into the solution. As a result, the activity test can be performed for a long time of 18 hours (3 hours in the case of the Watanabe method), and more reproducible data can be obtained. The dispersed pine wood nematode was obtained by separating from the pine sawyer, which emerged from pine from June to August. Proliferating pine wood nematodes
The same as that used in the lethal activity test described above. Table 5 shows the results.

[0021]

[Table 5]

[0022]

[Table 6]

[0024] Methyl ferulate and (+) pinoresinol, which have lethal activity on the proliferating pine wood nematode, are represented by the following formula and are present in the outer bark of Taiwanese horsetail pine.

[0024]

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These can be obtained by treating the outer bark of Taiwanese horsetail pine in the same manner as described above, dissolving with the same organic solvent, and separating and extracting. Methyl ferulate can also be obtained by methylating commercially available ferulic acid with diazomethane. These compounds were tested for lethal activity against proliferating pine wood pine. The test method is the same as above. The results are shown in Tables 7 and 8.

[0026]

[Table 7]

[0027]

[Table 8]

Furthermore, the present inventor has found that monohydroxystilbenes similar to pinosylvin monomethyl ether have an even stronger lethal activity against pine wood nematodes than the above-mentioned pinosylvin monomethyl ether. The lethal activity of monohydroxystilbenes and salts thereof against pine wood nematodes is shown in Tables 9 to 12 below. The activity test method was as follows. For this activity test, a Shimabara species of a proliferating pine wood nematode, which was purely subcultured, was used.

First, nematodes were put into a coefficient petri dish, and moving nematodes were counted under a microscope.

Next, the sample solution is placed in the dish, and
After storing in the dark at 0 ° C., the number of moving nematodes was counted again after 1 day and 2 days. The immovable nematodes were assumed to be dead, and the percentage of dead nematodes that lived first was calculated as the lethality. As a control solution for confirming whether the nematode really died from the sample, 1
% Ethanol solution was used.

[0031]

[Table 9]

[0032]

[Table 10]

[0033]

[Table 11]

[0034]

[Table 12]

Of these, 3-hydroxystilbene (Sample No. 11), 3-hydroxystilbene sodium salt (Sample No. 32), 3-hydroxystilbene potassium salt (Sample No. 33), and 2-hydroxystilbene (Sample No. 33) 9), 2-hydroxystilbene sodium salt (sample number 30), 2-hydroxystilbene potassium salt (sample number 31), 4-hydroxystilbene (sample number 13), 4-hydroxystilbene sodium salt (sample number 34), 3 -Hydroxystilbene potassium salt (sample number 35), 2-hydroxy, 3'-methoxystilbene (sample number 19), 2-hydroxy,
4'-methoxystilbene (Sample No. 22) and 3-hydroxy, 3'-methoxystilbene (Sample No. 26)
Is better. Hydroxystilbenes are synthesized as follows. Synthesis of hydroxystilbenes Methoxystilbene (C) was synthesized from benzylphosphonate (A) and methoxybenzaldehyde (B) by a Wittig-Horner reaction. Then, demethylation was performed with pyridinium chloride or boron tribromide to obtain hydroxystilbene (D).

[0036]

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A: Benzylphosphonate (A), which is a raw material of the Wittig-Horner reaction, has a-0, a-
2, a-3 was used.

[0038]

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Of these, a-0 was a commercial product, while a-2 and a-3 were synthesized as follows.

[0040]

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B: Methoxybenzaldehyde (B) which is another raw material of the Wittig-Horner reaction
Used b-2, b-3 and b-4. All commercial products were used.

[0042]

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C: The methoxystilbenes obtained by the Wittig-Horner reaction are as follows.

[0044]

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D: Methoxystilbene (C) was converted into hydroxystilbene by performing a demethylation reaction. Each is as follows. These compounds showed very strong nematicidal action.

[0046]

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For the demethylation reaction, a Lewis acid or the like can be used. Here, pyridinium chloride or boron tribromide was used, and the methods 1 and 2 were used, respectively. These nematicides containing a compound having a nematicidal activity as a main component contain about 1 to 10% of this active ingredient, and are used by being mixed with other known carriers and the like. Liquid and solid carriers are used as the carrier of the control agent containing the pine wood nematode repellent, the nematocide and the like according to the present invention, depending on the purpose of use. Liquid carriers can include water, alcohols, ketones, ethers, aromatic hydrocarbons, acid amides, esters, and the like. Examples of the solid carrier include known solid carriers such as mineral powder, alumina, sulfur powder, and activated carbon. The dosage form may be an injection, a spraying agent or the like. If necessary for these preparations, an emulsifier, a suspending agent, a stabilizer, a spreading agent, a penetrating agent, a dispersant and the like may be used, and the preparation can be carried out by a method known per se.

[0048]

The organic solvent extract of pine has an activity of controlling pine wood nematodes, and is obtained from pine or synthesized α.
-Humulene, or a mixture of α-humulene and β-bisabolene, and a mixture of α-pinene and caralene have a pine wood repellent action, and also methyl ferulate, (+)-pinoresinol or pinosylvin Hydroxystilbenes containing monomethyl ether have a nematicidal effect on pine wood.

[0049]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. 1. Preparation of an extract having pine wood nematode control activity
Ltd. 1) Sutorobu pine wood nematode control activity from Matsueda
Preparation of substance (1) 570 g of branches of pine pine are cut into small pieces and immersed in 3 liters of methyl alcohol at room temperature for 3 months.
Filtration yielded 3 liters of a methyl alcohol solution fraction.
0.6 L of pentane was added to the methyl alcohol solution fraction, and the mixture was shaken with pentant for 30 minutes in a separating funnel. 0.5 liters of the pentane solution and 3.1 liters of the methyl alcohol solution were separated and concentrated from the pentane solution to obtain 5 g of a volatile component. The physical properties of this volatile component were as a brown oil, [α] _D ²⁵ -6.0 ° (C5.9, CHC
l ₃ ). On the other hand, the methyl alcohol solution fraction was concentrated and freeze-dried to obtain a nonvolatile component. The physical properties of this nonvolatile component were a brownish viscous solid (FIG. 1). (2) 8 g of the above non-volatile component was dissolved in 0.3 liter of water, a) 0.6 liter of ethyl acetate was added, and the mixture was shaken in a separating funnel for 30 minutes to obtain 0.5 liter of ethyl acetate-soluble portion. Thus, 0.746 g of a nonvolatile extract was obtained. This was a viscous brown solid. Then
b) Add 0.6 liter of chloroform to the aqueous layer side and add
Similarly, the mixture was shaken for 0.5 minute to obtain 0.5 liter of chloroform-soluble portion, and 0.036 g of a nonvolatile extract was obtained. further,
c) 0.6 liter of butanol was added to the aqueous layer side and shaken similarly to obtain 0.5 liter of a butanol-soluble part,
1.556 g of a non-volatile extract was obtained (FIG. 2).

2) Matsunoise from strobe pine heartwood
Preparation of an active substance for controlling roots of a tree 11.2 kg of a heartwood was finely chopped and immersed in 30 liters of methyl alcohol at room temperature for 3 months. Then, the mixture was filtered to obtain 30 liters of a methyl alcohol solution. This solution was treated (see FIGS. 2 and 3) in the same manner as described above for the branch (see above), and the ethyl acetate-soluble portion (8
2.1 g) and a butanol-soluble portion (17.3 g). (1) The ethyl acetate-soluble portion (82.1 g) was further subjected to silica gel chromatography, and the MeOH: CHCl ₃ mixed solvent was adjusted to a ratio of 1: 9 (v / v) to 2: 8 (v / v) by Me.
Elution was performed with increasing proportions of OH. MeOH: CHCl ₃
Active fractions A-1 (3.5 g) and M eluted at 1: 9
A-2 eluted with MeOH: CHCl ₃ 2: 8 (25.
8 g) were obtained. (2) The butanol-soluble part (17.3 g) was subjected to gel filtration chromatography, silica gel chromatography, and then preparative high performance liquid chromatography to obtain pinosylvin monomethyl ether (20 mg).

2. Pine mosquito repellent activity and killing
Preparation of dead active substance (1) Preparation of α-humulene A commercially available α-humulene (manufactured by Tokyo Chemical Industry Co., Ltd.) was used. A mixture of repellent active terpene hydrocarbons containing α-humulene and caralene was prepared from the heartwood of Matsumatsu by the following method. The heartwood (13 kg) of horsetail pine was finely chopped and immersed in methyl alcohol (50 liters). After filtration, 18 liters of pentane was added to the obtained methyl alcohol solution (50 liters) and shaken to obtain a pentane solution (16 liters). The pentane solution was concentrated to obtain a volatile component (14 g). The volatile component was subjected to silica gel chromatography to obtain a mixture I (1.1 g) and a mixture II (1.5 g) of two terpene hydrocarbons exhibiting nematode repellent activity. According to gas chromatography and gas chromatography mass spectrometry, mixture I contains α-humulene (60%) and β-bisabolene (40%), while mixture II contains
It was found that it contained α-pinene (60%) and caralene (40%). (2) Preparation of Methyl Ferulate Methyl ferulate was obtained by methylating commercially available ferulic acid (manufactured by Tokyo Chemical Industry Co., Ltd.) with diazomethane or hydrogen chloride saturated methyl alcohol (Fisher method).

It was also isolated from the outer bark of Pine Matsu along with (+)-pinoresinol. (3) Preparation of Methyl Ferulate and (+)-Pinoresinol from Outer Bark of Pine Pine The outer bark (14 kg) of Pine Pine was cut into small pieces and immersed in methyl alcohol (15 L) for 3 months. After filtration, the resulting methyl alcohol solution was treated in the same manner as for the strobe pine [(above), (FIG. 2)] to obtain a butanol-soluble part (29 g). This was subjected to gel filtration chromatography, silica gel chromatography, and then preparative high performance liquid chromatography to obtain methyl ferulate (6 mg) and (+)-pinoresinol (3 mg).

3. Synthesis of hydroxystilbenes 1) Synthesis of 3-hydroxystilbene (Sample No. 11) (Wittig-Horner reaction) 5.0 g of 3-methoxybenzaldehyde (b-3) in 50 ml of anhydrous DMF (dimethylformamide) under a nitrogen atmosphere. 36.8m
mol) and diethylbenzylphosphonate (a-0) 1
Dissolve 0.1 g (44.1 mmol). While cooling to 0 ° C. in an ice bath, 8.9 ml (45.9 mm) of a methanol solution containing 28% sodium methoxide was added to this solution.
ol). The mixture is stirred at 0 ° C. for 1 hour and further at room temperature overnight. 200 ml of water was added to the reaction solution,
Extract with ethyl acetate (200 ml × 3). The ethyl acetate extract containing 3-methoxystilbene (c-0.3) was washed with water (50 ml × 2) and dried over anhydrous Na ₂ SO ₄ .
Filter and concentrate under reduced pressure. To this, methanol-water (1:
(4 v / v), 100 ml was added and dissolved, and the mixture was placed in a refrigerator overnight. As a result, 7.0 g (yield 90.8%) of 3-methoxystilbene (c-0.3) was obtained as pale yellow crystals.

(Demethylation reaction / method 1) 6.9 g (32.9 mmol) of 3-methoxystilbene (c-0.3)
l) to 16 g of pyridinium chloride (138.5 mm
ol) and stirred at 180 ° C. for 4 hours. After cooling, the mixture was cooled in an ice bath, a 2M aqueous HCl solution (about 100 ml) was added until the reaction solution became acidic, and extracted with ether (20 ml).
0 ml × 3). The ether layer is dried over anhydrous Na ₂ SO ₄ and filtered, and the solvent is distilled off under reduced pressure to obtain a brown oil containing 3-hydroxystilbene (d-0.3) (sample No. 11). This oil was subjected to column chromatography [SiO ₂ : 200 g, hexane-ethyl acetate (9: 1).
v / v)], and further recrystallized from hexane-ethyl acetate to give 3-hydroxystilbene (sample No. 11) (mp. 117-118 ° C.) as white crystals.
9 g (76.9% yield) are obtained. Similarly, 4-
4-methoxystilbene was synthesized from methoxybenzaldehyde and diethylbenzylphosphonate and then demethylated to give 4-hydroxystilbene (Sample No. 1).
3) (white needle crystals, mp 185-186 ° C).
2-Hydroxystilbene was similarly synthesized from 2-methoxybenzaldehyde and diethylbenzylphosphonate by first synthesizing 2-methoxystilbene and then by demethylation according to Method 2 shown below.

(Demethylation reaction / Method 2) Under a nitrogen atmosphere, 7.75 g of 2-methoxystilbene (c-2) (3
6.9 mmol) in anhydrous dichloromethane. Into this, 40 ml of a dichloromethane solution containing 3.2 g (12.9 mmol) of boron tribromide is added dropwise at -78 ° C (dry ice-acetone bath), and the mixture is stirred at room temperature overnight.
The reaction solution is cooled in an ice bath, and a 10% aqueous KOH solution is added little by little to decompose the boron complex formed in the reaction solution. The reaction solution was transferred to a separating funnel, 2M HCl was added until the aqueous layer became acidic, and the mixture was extracted with chloroform (20).
0 ml × 3). Wash the chloroform layer with water (50 ml x
2) After drying with anhydrous Na ₂ SO ₄ , filtration and removal of the solvent under reduced pressure, a brown oil containing 2-hydroxystilbene (d-2) is obtained. The oil was purified by column chromatography [SiO _2: 200 g, hexane - ethyl acetate (9: 1)] to give further hexane - recrystallized from ethyl acetate, 2-hydroxy-stilbene of white needles (d-2 ) (Sample No. 9) (mp 138-13)
5.0 ° g (69.9% yield).

2) Preparation of hydroxystilbene salts

[0057]

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[0058]

[Table 13]

1.120 g of 3-hydroxystilbene
(5.71 mmol) was dissolved in a small amount (about 5 ml) of ethanol, and 59.9 ml of a 0.095 N NaOH aqueous solution (titrated with a 0.1 N oxalic acid solution) was added to this solution.
(5.71 mmol) are added dropwise. When this solution was freeze-dried as it was, 1.276 g of 3-hydroxystilbene sodium salt (sample No. 32) was obtained as an off-white powder.
(101.8% yield). It is more than the equivalent, but it is thought to be due to moisture. Also, sodium salt of 2-hydroxystilbene (sample No. 30) and sodium salt of 4-hydroxystilbene (sample No. 3) were obtained from 2-hydroxystilbene and 4-hydroxystilbene, respectively.
4) was obtained. Similarly, 1.398 g (7.13 mmol) of 4-hydroxystilbene is dissolved in a small amount of ethanol (about 5 ml), and 64.2 ml of a 0.111 NKOH aqueous solution is added dropwise. 4-hydroxystilbene potassium salt (Sample No. 35) was 1.6 as a pale yellow powder.
88 g were obtained. Similarly, from 2-hydroxystilbene and 3-hydroxystilbene, yellow powder, hygroscopic potassium salt of 2-hydroxystilbene (sample No. 3)
1) and a white powder of 3-hydroxystilbene potassium salt (Sample No. 33) were obtained.

3) Synthesis of 2-hydroxy, 4'-methoxystilbene (Sample No. 22) (Synthesis of starting material 2-methoxybenzylphosphonate (a-2)) (1) 2.0 g of 2-methoxybenzaldehyde (14.
7 mmol) in 10 ml of methanol solution.
5 ml of a methanol solution containing 0.6 g (16.0 mmol) of H _{4 is} added dropwise, and the mixture is stirred at room temperature for about 1 hour. After confirming the progress of the reaction by thin layer chromatography, 100 ml of water is poured into the reaction solution to decompose excess NaBH ₄ and extract with ether (30 ml × 3). The ether layer is dried over anhydrous Na ₂ SO ₄ , filtered, and the solvent is distilled off, thereby obtaining 1.95 g (yield: 96.1%) of 2-methoxybenzyl alcohol as a colorless oil. (2) 1.75 g of 2-methoxybenzyl alcohol (1
2.7 mmol) in 20 ml of anhydrous benzene.
Stir at 0 ° C. (ice bath) for about 20 minutes while blowing in Br gas. After refluxing the reaction solution for 2 hours, benzene is distilled off under reduced pressure. Silica gel column chromatography [SiO ₂ : 200 g, hexane-ethyl acetate (96:
4)] and recrystallizing from methanol to obtain 0.86 g (yield 33.8%) of methoxybenzyl bromide as white crystals. (3) 2-methoxybenzyl bromide 450mg
Excess triethyl phosphite ^{0.7ml (4.1 × 10 ~ 3 mol} ) was added to (2.2mmol), 130 ℃
For about 1 hour until no generation of ethylno under the odor is observed. After the reaction, excess triethyl phosphite was distilled off under reduced pressure, and the brown oily 2-methoxybenzylphosphonate (a-2) (630 mg) obtained as a residue was purified without purification by the next Wittig-Horner reaction. Used for This reaction was assumed to have progressed quantitatively.

(Wittig-Horner reaction) 2-
Methoxybenzylphosphonate (a-2) 630mg
(2.2 mmol) under a nitrogen atmosphere is added 4 ml of anhydrous N, N-dimethylformamide. 150 mg (2.8 mmol) of sodium methoxide are added to this mixture while cooling to 0 ° C. in an ice bath. Subsequently, 0.3 m of 4-methoxybenzaldehyde
1 (2.5 mmol) was added dropwise and stirred at 0 ° C. for 1 hour,
Stir at room temperature overnight. 20 ml of water is added to the reaction solution, and extracted with ethyl acetate (20 ml × 3). The ethyl acetate layer was washed with water (5 ml × 2), dried over anhydrous Na ₂ SO ₄ and concentrated under reduced pressure to obtain 1.3 g of a crude product. This was subjected to silica gel column chromatography [SiO ₂ : 50 g,
Hexane-ethyl acetate (9: 1)].
4'-dimethoxystilbene (c-2.4, sample number 2
394 mg (yield: 74.7%) of white crystals of 1) are obtained.

(Demethylation reaction) To 200 mg (1.73 mmol) of 2,4'-dimethoxystilbene, 200 mg (1.7 mmol) of pyridinium chloride was added.
Stir at 70 ° C. for 3 hours. After allowing to cool, cool in an ice bath and add 2M
Add 2 ml of aqueous HCl. Extract with ether (20
ml × 3), the ether layer was dried over anhydrous Na ₂ SO ₄ , filtered, and the solvent was distilled off under reduced pressure to obtain a reaction mixture. This mixture was subjected to silica gel column chromatography [Si
O ₂ : 50 g, hexane-ethyl acetate (9: 1 → 8:
2)] to separate into raw materials, dihydroxy form and monohydroxy form. When the monohydroxy form was further separated by high performance liquid chromatography [Wakopack Wakosil, hexane ethyl acetate (9: 1)], 2
-Hydroxy, 4'-methoxystilbene (d-2.
4, sample No. 22) as colorless needle crystals (mp 142-
143 ° C.) in an amount of 5.13 mg (6.8% yield).
2-hydroxy, 3'-methoxystilbene (Sample No. 19) pale yellow oil and 3-hydroxy, 3'-methoxystilbene (Sample No. 26) colorless powdery crystals (mp.
78-79 ° C.) was also synthesized in the same manner as in the above-mentioned synthesis of 2-hydroxy, 4′-methoxystilbene (sample No. 22).

Example 1 A powder or liquid is prepared by mixing 1-2% of a repellent α-humulene component with other known carriers. Example 2 An injectable is prepared as an organic solvent ampoule containing 1 to 2% of the nematicide methyl ferulate component for injecting into a pine temporary conduit. Example 3 An injection containing 1 to 2% of a hydroxystilbene component for injecting into a temporary pine conduit as an organic solvent ampule is prepared.

[Brief description of the drawings]

FIG. 1 is a drawing showing a process of extracting an active ingredient from pine.

FIG. 2 is a drawing illustrating a process of extracting a pine wood nematode lethal active substance from strobe pine.

FIG. 3 is a process chart of extracting a pine wood nematode lethal active substance present in a strobe pine heartwood.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 65/00 A01N 27/00 A01N 37/10 A01N 43/00

Claims (8)

(57) [Claims] 1. A pine wood nematode control agent containing an organic solvent extract of pine. 2. The pine wood nematode controlling agent according to claim 1, wherein the pine is a stove pine, a rhubarb pine or a horse pine. 3. The pine wood nematode controlling agent according to claim 1, wherein the organic solvent is an alcohol, a hydrocarbon, a chlorinated hydrocarbon, an acetate or a ketone. 4. A pine wood nematode repellent containing α-humulene or a mixture of α-humulene and β-bisabolene. 5. A pine wood nematode repellent containing a mixture of α-pinene and caralene. 6. A pine wood nematocide containing methyl ferulate, (+)-pinoresinol or a mixture thereof. 7. A pine wood nematode comprising a hydroxystilbene or a salt thereof. 8. Hydroxystilbenes or salts thereof are pinosylvin monomethyl ether, pinosylvin monomethyl ether sodium salt, pinosylvin monomethyl ether potassium salt, 3-hydroxystilbene, 3-hydroxystilbene sodium salt, 3-hydroxystilbene Potassium salt, 2-hydroxystilbene, 2-hydroxystilbene sodium salt, 2-hydroxystilbene potassium salt, 4-hydroxystilbene, 4-hydroxystilbene sodium salt, 4-hydroxystilbene potassium salt, 2,3′-dihydroxystilbene,
The pine wood nematode nematocide according to claim 7, which is 2-hydroxy, 3'-methoxystilbene, 2-hydroxy, 4'-methoxystilbene, and 3-hydroxy, 3'-methoxystilbene.