JP2545743B2 - Herbicide containing epoxy compound - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a herbicide containing a specific epoxy compound.

[0002]

The epoxy compound used as an active ingredient of the herbicide of the present invention is
Not to mention its manufacturing method, its use is completely unknown. In the process of studying the action mechanism of phytopathogenic filamentous fungi, the present inventors have confirmed that two microorganisms belonging to the genus Pestalothia and the genus Pestallotiopsis produce physiologically active substances with high herbicidal activity. It was confirmed and the present invention was completed based on this finding.

[0003]

That is, the present invention provides an epoxy compound represented by the following formula (I):

[0004]

Embedded image

( Wherein R is 3-methyl-3-butene-1)
Represents an -ynyl group . ) As an active ingredient.

The epo of the present invention represented by the above general formula (I)
In the xy compound, the substituent R is 3-methyl-3-butene-1.
A group represented by -ynyl group .

This epoxy compound can be obtained by culturing a microorganism belonging to the genus Pestalothia or the genus Pestalothiopsis and having the ability to produce the epoxy compound, and collecting the epoxy compound from the culture. Among the microorganisms, Pestalothia longiseta Spegaccini PL8501
The strain was isolated from the leaf spots affected by tea ring spot disease in Toyohashi City, Aichi Prefecture. This fungus has been deposited at the Fermentation Research Institute as IFO 32172, and its mycological properties are as follows.

[Morphological Findings] Conidia of Pestallotia longiseta spegaccini consist of slightly curved 5 cells and have a size of 16 to 27 × 6.0 to 9.2 μm (average 24 × 8).
μm), the central 3 cells have a length of 14 to 19 μm (16 μm).
m), dark brown, of which the upper 2 cells are particularly dark, the cells at both ends are colorless, the apical accessory threads are usually 3, colorless, cylindrical, 8 to
31μm (25μm), base attached yarn is colorless, straight,
It is 5 to 11 μm.

[Growth state] Growth on a potato decoction agar medium supplemented with 2% sucrose is good. The flora is white with a slight gray tinge. Most strains readily form a large number of black droplets of spores on the lawn. The growth temperature is 12 to 32 ° C, and the optimum growth temperature is 28.
It is around ° C.

The Pestallotiopsis thiae T-5-6 strain used in the present invention was isolated from the leaf spot of Cha-ring spot disease collected in Aioi-cho, Naka-gun, Tokushima Prefecture. This bacterium has been deposited at the Fermentation Research Institute as IFO 32327, and its mycological properties are as follows.

[Morphological Findings] Conidia of Pestallotiopsis tiae have a spinal shape, straight, and rarely curved.
The size of cells is 22-34 x 5.5-8 μm (27 x 7.2 μm on average), and the central 3 cells are 15-22 μm in length.
(18 μm) is brown and almost the same color, cells at both ends are colorless, apical accessory threads are usually 3, colorless, cylindrical to spatula-shaped, 15 to 50 μm (30 μm), base accessory threads are colorless, straight 4 to 4 It is 10 μm.

[Growth state] Growth on a potato decoction agar medium supplemented with 2% sucrose is good. The flora is white with a slight gray tinge. Most strains readily form a large number of black droplets of spores on the lawn. As the culture grows longer, the medium turns brown. The growth temperature is 12 to 32 ° C, and the optimum growth temperature is around 28 ° C.

The epoxy compound used in the present invention is a microorganism belonging to the genus Pestalothia or genus Pestalothiopsis and having the ability to produce the epoxy compound represented by the general formula (I) is added to a medium in which the microorganism can grow. It can be produced by culturing. For example, in a liquid medium in which glucose, peptone, etc. are added to potato decoction (potato 200 g / water 1000 ml), Pestalothia longiseta spegaccini or Pestalothiopsis thiae at 24-29 ° C. It is produced in the medium by culturing for 3 days or more.

In order to obtain the desired epoxy compound from the culture, a known method may be applied. As an example of the method, the supernatant obtained from the culture by solid-liquid separation means such as vacuum filtration may be used as an organic solvent. Extraction was performed by adding a solvent such as ethyl acetate, and the obtained extract was used with a suitable adsorbent such as silica gel and an eluent such as a mixture of benzene-acetone and methanol: water (20:80). It can be isolated by fractionating by column chromatography or the like, collecting an active fraction, and repeating purification treatment.

[0015]

EXAMPLES Next, the present invention will be described in detail with reference to Examples. Production Example 1 Potato decoction liquid medium containing glucose 2% and peptone 0.5% (pH 6.2 to 6.3 after autoclaving) 5
Add 0 ml to a 300 ml Erlenmeyer flask and place at 121 ° C.
Heat sterilized for 10 minutes. Pestalothia longiseta
Pegasotini (Pestaloti a longiseta ) PL8501 strain (IFO 321
72, this fungus was rejected by the Institute of Biotechnology, Institute of Industrial Science and Technology) for 3 days in 2% sucrose-supplemented potato decoction agar medium. Inoculate 280 Erlenmeyer flasks containing the above liquid medium with each of the lawn pieces punched out with a cork borer, and incubate at 28 ° C for 5 days in the dark (cover the Erlenmeyer flask with aluminum foil and completely block the light). The culture was performed.

After completion of the culture, bacterial cells and other solid substances were filtered out from the culture solution to obtain 11.7 liters of culture filtrate. An operation of adding an equal amount of ethyl acetate to the filtrate and performing extraction was performed twice to obtain 23.4 liters of an ethyl acetate solution containing the target substance. This was concentrated under reduced pressure to obtain an extract. This extract was redissolved in a small amount of benzene: acetone (85:15), applied to 5 silica gel columns (2 cm × 15 cm), and benzene: acetone (85:15) was used as an elution solvent.
Was eluted with. Each fraction was assayed using the ability to form necrotic spots on tea leaves as an index, and the target product was confirmed by thin layer chromatography using benzene: acetone (60:40) as a developing solvent (Rf = 0.31). The active fractions were collected and concentrated to dryness under reduced pressure. Further, the same column chromatography was performed once using benzene: acetone (80:20) as an elution solvent, active fractions were collected and concentrated to dryness under reduced pressure to obtain 730 mg of a crude product. Redissolve this in methanol: water (20:80),
Octadecylsilane of _{7.8mm × 30cm (ODS-C 18} .1
0 μm) column and subjected to high performance liquid chromatography to fractionate the active fraction with methanol: water (20:80) as an eluent, wherein compound A (R in the general formula (I) is a hydroxy-substituted methyl group) Compound) 577 mg
I got

Specific rotation of compound A, UV absorption spectrum, IR absorption spectrum, mass spectrum, ¹ H-NM
The R and ¹³ C-NMR measurement results were as follows. [Α] _D ²⁵ + 261 ° (c = 1.0, MeOH); UV
_max (MeOH) 240 nm (ε8100); IR (K
Br) 3600 to 3200, 2920, 1670c.
m ⁻¹ ; EIMS m / z 156 (M ⁺ ), 138 (M-H ₂
O); ¹ H-NMR (270 MHz, CDCl ₃ ) δ 2.16
(1H, t, J = 6.3Hz), 2.22 (1H, d, J =
8.8Hz), 3.51 (1H, dd, J = 3.7, 1.1H
z), 4.04 (1H, m), 4.24 (1H, dd, J =
14.5, 6.3 Hz), 4.40 (1H, dd, J = 14.
5,6.3Hz), 4.75 (1H, m), 6.69 (1H,
m); ¹³ C-NMR (67.8 MHz, CDCl ₃ ) δ 53.
4,57.5,60.6,63.0,136.3,138.8,1
94.1.

Example 2 30 ml of 50 ml in a potato decoction liquid medium containing 2% glucose (pH 6.2 to 6.3, after autoclaving)
The mixture was placed in a 0 ml Erlenmeyer flask and heat-sterilized at 121 ° C. for 10 minutes. Pestalotiopsis
opsi s theae) T-5-6 strain (IFO 32327, this bacterium was refused the contract at the Institute of Biotechnology, Institute of Biotechnology)
% Sucrose-added potato decoction agar medium was cultivated for 3 days for 3 days, and the flora pieces punched out with a cork borer of 4 mm in diameter from the periphery of the flora were put into 70 Erlenmeyer flasks containing the liquid medium, respectively. After inoculation, the cells were statically cultured at 27 ° C. for 4 days in the dark (the Erlenmeyer flask was covered with aluminum foil to completely block the light).

After the completion of the culture, bacterial cells and other solid substances were separated from the culture solution by filtration to obtain 2.8 liters of the culture filtrate. The operation of adding an equal amount of ethyl acetate to this filtrate and performing extraction twice,
5.6 liters of an ethyl acetate solution containing the desired product was obtained.
This was concentrated under reduced pressure to obtain an extract. This extract was redissolved in a small amount of benzene: acetone (95: 5), applied to a silica gel column (2 cm × 15 cm), and eluted using benzene: acetone (95: 5) as an elution solvent. Each fraction was assayed with the ability to form necrotic spots on tea leaves as an index, and benzene: acetone (60:40).
The target product was confirmed by thin-layer chromatography using as a developing solvent (Rf = 0.75), and active fractions were collected and concentrated to dryness under reduced pressure. 48 mg of crude product are obtained. This is redissolved in methanol: water (60:40), 7.8 mm x 30 c
subjected to high performance liquid chromatography using octadecyl silane (ODS-C ₁₈ .10μm) column m, methanol: fractionated active fractions water (60:40) as eluant min, the compounds of the present invention B (the general A compound in which R in the formula (I) is a 3-methyl-3-butene-1-ynyl group)
28.4 mg was obtained.

Specific rotation of the above compound B, UV absorption spectrum, IR absorption spectrum, mass spectrum, ¹ H-NM
The R and ¹³ C-NMR measurement results were as follows. [Α] _D ²⁵ + 147 ° (c = 0.82, MeOH); UV
_max (MeOH) 247 nm (ε9870); IR (K
Br) 3600-3200, 2950, 2900, 21.
90,1690 cm ^-1 ; EIMS m / z 190 (M ⁺ ).
, 162 (M-CO), 161 (M-CHO); ¹ H
-NMR (270 MHz, CDCl ₃ ) δ 1.94 (3H,
s), 2.19 (1H, d, J = 8.8Hz), 3.58 (1
H, dd, J = 3.4, 1.0 Hz), 3.82 (1H,
m), 4.78 (1H, m), 5.35 (1H, s), 5.4
4 (1H, s), 6.86 (1H, dd, J = 4.9, 2.4)
Hz); ¹³ C-NMR (67.8 MHz, CDCl ₃ ) δ2
3.0, 53.5, 57.5, 63.3, 81.2, 95.9, 12
2.1, 124.1, 125.9, 145.6, 191.0.

Example 1 Herbicidal Activity Test I Knotweed ( Polygoun m cuspidatum ), Himejoon (Eri )
gero n annuus ), mugwort (Artemisia p rinceps) , Harta de (Polygonum p ersicaria) , Commelina c ommu
The isolated leaves of ( nis) were tested, and 30 μl of an aqueous solution of compound B having a predetermined concentration was added dropwise to a piece of filter paper having a diameter of 6 mm placed on a wounded portion or an unwounded portion with seven bundled cotton needles. After the separated leaves were kept in a humid chamber at 25 ° C. for 48 hours, the presence or absence of necrotic plaque formation and its degree were examined. The test concentrations in this test are 1000, 100, and 10 μg / ml. The results are as shown in Table 1.

[0022]

[Table 1]

Example 2 Herbicidal activity test II Knotweed ( Polygoun m cuspidatum ), Himejoon (Eri )
gero n annuus ), and leaves of Artemisia p rinceps were tested, and compound A and compound B were placed on a piece of filter paper with a diameter of 6 mm, which was placed on the wounded or intact part with 7 cotton needles. 30 μl of an aqueous solution having a predetermined concentration was added dropwise. After the separated leaves were kept in a humid chamber at 25 ° C for 48 hours, the presence or absence of necrotic spot formation was examined. The concentration at which the necrotic plaque was finally visible was defined as the minimum necrotic plaque formation concentration. The test concentrations in this test are 1000, 500, 250, 12
5, 62.5, 31.3, 15.6, 7.8, 3.9, 2.0, 1.0
μg / ml. The results are shown in Table 2.

[0024]

[Table 2]

[0025]

The epoxy compound according to the present invention has excellent herbicidal activity against weeds such as Japanese knotweed and Himejoon, and is therefore expected to be used as a herbicide in agricultural land.

Claims (1)

(57) [Claims] 1. An epoxy compound represented by the following formula (I): ## STR1 ## wherein R is 3-methyl-3-buten-1-y.
Indicates a nyl group . ) As an active ingredient.