JP2676383B2 - 2H-cyclopenta [b] furan derivative, its production method and agricultural / horticultural fungicide containing the same as an active ingredient - Google Patents

Description

TECHNICAL FIELD The present invention relates to a 2H-cyclopenta [b] furan derivative represented by the following formula (1), which is useful as an active ingredient for controlling plant diseases, a method for producing the same, The present invention relates to an agricultural and horticultural fungicide containing an intermediate in the production process and the 2H-cyclopenta [b] furan derivative as an active ingredient.

2. Description of the Related Art Conventionally, many compounds having a triazole group have been proposed as an active ingredient of agricultural and horticultural fungicides, but no compound having a triazole group bonded to 2H-cyclopenta [b] furan is known.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present inventors develop a fungicide for agricultural and horticultural use, which has low toxicity to humans and animals, is highly safe in handling, and has an excellent control effect against a wide range of plant diseases. Therefore, as a result of synthesizing a large number of azole derivatives and examining the practicality thereof, the 2H-cyclopenta [b] furan derivative represented by the formula (1) is effectively used as an agricultural / horticultural fungicide having the above-mentioned properties. They have found that they can be applied and have completed the present invention. Therefore, the present invention aims to provide a 2H-cyclopenta [b] furan derivative useful as an active ingredient of an agricultural / horticultural fungicide, a method for producing the same, and an agricultural / horticultural fungicide containing the same as an active ingredient. To do.

Structure of the Invention The structure of the present invention is characterized by the following formula (1). 6- (4-chlorobenzyl) -3,3a, 4,5,6,6a-hexahydro-6a- (1H-1,2,4-triazol-1-ylmethyl) -2H-cyclopenta [b] furan, 4- (4-chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane and 1,2,4-triazole are reacted with 2H represented by the above formula (1).
-Method for producing cyclopenta [b] furan derivative and 2H-cyclopenta [b] represented by the above formula (1)
It is an agricultural and horticultural fungicide containing a furan derivative as an active ingredient.

The 2H-cyclopenta [b] furan derivative represented by the above formula (1) is a novel compound which has not been published in the literature. The infrared absorption spectrum of this compound in Fig. 1, ¹ H-NMR
The spectra are shown in FIG. 2, respectively.

(Note) The display of the position in formula (1) is as follows. Means for Solving the Problems Production method for obtaining a 2H-cyclopenta [b] furan derivative represented by the above formula (1) according to the present invention and the 2H-
Use of the cyclopenta [b] furan derivative as a fungicide for agricultural and horticultural purposes will be described.

The 2H-cyclopenta [b] furan derivative according to the present invention is produced by the following method.

4- (4-chlorobenzyl) represented by the following formula (2)
-7- (2-Fluoroethyl) -1-oxaspiro [2.
4] Heptane is reacted with 1,2,4-triazole represented by the following formula (3) in the presence of a diluent to obtain a 2H-cyclopenta [b] furan derivative represented by the above formula (1). (M in the formula (3) represents a hydrogen atom or an alkali metal) As the diluent used in the above production method, hydrocarbons such as benzene, toluene, xylene and hexane; halogens such as methylene chloride, chloroform and carbon tetrachloride Hydrocarbons; alcohols such as methanol and ethanol; ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran and dioxane; other examples are acetonitrile, acetone, dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and the like. obtain.

In carrying out the above-mentioned production method, for example, 1,2,4-triazole dissolved in the above-mentioned diluent is added to 4- (4-
0.5-1.0 equivalent of chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane is added,
Or conversely 4- (4-chlorobenzyl) -7- (2-
Fluoroethyl) -1-oxaspiro [2.4] heptane may be dissolved in a diluent to which an alkali metal salt of 1,2,4-triazole may be added for reaction.

As the reaction temperature at this time, any temperature from the freezing point to the boiling point of the diluent as a solvent can be applied.
It is preferable to carry out the reaction at a temperature in the range of 100 to 100 ° C.
The reaction time is in the range of 1 to 3 hours, and the reaction is preferably carried out with stirring.

After completion of the above reaction, the reaction mixture obtained by the reaction was cooled and then poured into ice water, ethyl acetate, chloroform,
Separate the organic layer by extracting with an organic solvent such as benzene,
Then, the organic layer is washed with water and dried, the solvent is distilled off under reduced pressure, and the obtained residue is subjected to purification treatment to obtain the target compound. The purification treatment can be performed by recrystallization, silica gel column chromatography or the like.

The 4- (4-chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane used as the starting material here is synthesized from methyl 2-oxocyclopetanecarboxylate through the following steps. You can

That is, from 2-oxocyclopentanecarboxylate methyl (4) and 4-chlorobenzyl halide, 1- (4-
Methyl chlorobenzyl) -2-oxocyclopentanecarboxylate (5) was obtained, and the compound of (5) was added to methanol.
By heating under reflux in the presence of sodium methylate,
Methyl 3- (4-chlorobenzyl) -2-oxocyclopentanecarboxylate (6) can be obtained. next,
3- (4-chlorobenzyl) -1 by reacting the compound of (6) with 1-bromo-2-fluoroethane using sodium hydride as the base in dimethylformamide.
Methyl-(2-fluoroethyl) -2-oxocyclopentanecarboxylate (7) was obtained, followed by heating to 100 ° C. in a mixed solvent of 47% hydrobromic acid-acetic acid,
2- (4-Chlorobenzyl) -5- (2-fluoroethyl) cyclopentanone (8) is obtained. 4- (4-chlorobenzyl) -7 was obtained by reacting the compound of (8) with dimethyloxosulfonium methylide prepared by mixing equal amounts of sodium hydride and trimethylsulfoxonium halide in dimethylsulfoxide. −
(2-Fluoroethyl) -1-oxaspiro [2.4] heptane (2) can be obtained.

Methyl 3- (4-chlorobenzyl) -2-oxocyclopentanecarboxylate intermediately generated in the above reaction,
2- (4-chlorobenzyl) -5- (2-fluoroethyl) -cyclopentanone and 4- (4-chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane have not been reported in the literature. It is a listed compound.
The respective NMR spectra are shown in FIGS.

Next, 2H represented by the chemical formula (1) according to the present invention
The usefulness of the cyclopenta [b] furan derivative (hereinafter referred to as the compound of the present invention) as an active ingredient of an agricultural / horticultural fungicide will be described.

The compound of the present invention exhibits an excellent controlling effect against a wide range of plant diseases shown below.

Rice blast (Pyricularia oryzae), rice sesame leaf blight (Cochliobolus miyabeanus), rice white leaf blight (Xanthomonas oryzae), rice wilt (Rhizoctonia)
solani), a rice black rot (Helminthosporium sigmo)
ideum), rice scabbard disease (Gibberella fujikuroi),
Apple powdery mildew (Podosphaera leacotricha), apple scab (Venturia inaequalis), apple monilinia mali, apple leaf spot disease (Alte)
rnaria mali), apple rot (Valsa mali), pear black spot (Alternaria kikuchiana), pear powdery mildew (Phyllactinia pyri), pear scab (Gymnosporan)
gium asaticum), pear scab (Venturia nashicol)
a), Grape powdery mildew (Uncinula necator), Grape rust (Phakopsora ampelopsidis), Barley powdery mildew (Erysiphe graminis f.sp hordei), Barley cloud disease (Rhynchosporium secalis f.sp.horde)
i), barley black rust (Puccinia graminis), barley yellow rust (Puccinia striiformis), wheat leaf rust (Puccinia recondita), wheat leaf blight (Sept.
ria trtici), wheat stripe rust (Puccinia striiform)
is), wheat powdery mildew (Erysiphe graminis f.sp.tri
tici), powdery mildew of cucurbits (Sphaerotheca fuligine
a), Fusarium oxysporum f.sp.niv
eum), powdery mildew of tomato (Erysiphe cichoracearu
m), tomato ring spot (Alternaria solani), eggplant powdery mildew (Erysiphe cichoracearum) d, strawberry powdery mildew (Sephaerotheca humuli), tobacco powdery mildew (Erysiphe cichoracearum), tobacco scab (Altern).
aria longipes), brown spot of sugar beet (Cercospora beti)
cola), summer blight of potato (Alternaria solani),
Brown spot of soybean (Septoria glycines), Purpura of soybean (Cercospora kikuchii), Fusarium wilt of cucumber (Fusar)
ium oxysporum f.sp.cucumerinum) Cucumber powdery mildew (Sphaerotheca fuliginea) Radish yellow fever (Fusarium
oxysporum f.sp.raphani) Anthracnose (Celletotric)
hum lagenarium) Late rot of grapes (Glomerilla cingulat
a) Green bean mold (Botrytis cinerea) Stone scab (Monilinia fructicola) of fruit trees, Botrytis cinerea, sclerot disease (Sclero)
tinia sclerotiorum) and the like.

In addition, the compound of the present invention exerts not only a preventive control effect but also a therapeutic effect against some of the plant diseases listed above.

To apply the compound of the present invention as an agricultural and horticultural fungicide,
The compound can be advantageously used as it is or as a mixture with a carrier (diluent) in the form of powders, wettable powders, granules, emulsions, liquids and the like. Further, it is of course possible to further enhance the effect by adding an auxiliary agent such as a spreading agent, an emulsifying agent, a wetting agent, and a fixing agent in addition to the above carrier, if necessary.

Incidentally, since this compound contains a 1,2,4-triazole ring, it can be used in the form of an inorganic acid salt, an organic acid salt or a metal complex salt.

In addition, the compound of the present invention includes 3a-position, 6-position of the bicyclic skeleton,
Since there is an asymmetric carbon at the 6a position, geometric isomers such as cis and trans isomers and stereoisomers such as optical isomers may exist, but in the present invention, all of these single isomers and individual isomers It also includes a mixture in any ratio.

Therefore, it should be understood that the agricultural and horticultural fungicides according to the present invention include those containing, as an active ingredient, these isomers alone or as a mixture.

EXAMPLES AND EFFECTS The effects will be described below with reference to specific production methods of the compound of the present invention and specific examples of agricultural and horticultural fungicides using the compounds as active ingredients.

Example 1 (1) Synthesis of methyl 1- (4-chlorobenzyl) -2-oxocyclopentanecarboxylate 500 ml of anhydrous methylformamide, sodium hydride (60% oily sodium hydride washed with anhydrous hexane) 33.6 g (0.84 mol) was added, and 100 g (0.7 mol) of methyl 2-oxocyclopentanecarboxylate was added to this.
It was dropped over time. Then add to this mixture at room temperature 4-
After adding 135 g (0.84 mol) of chlorobenzyl kilolide over 1.5 hours, it heated up at 80 degreeC and stirred for 3 hours.

The obtained reaction solution was allowed to cool, then poured into ice water and extracted with ethyl acetate to obtain an organic layer, and the organic layer was washed with 1N hydrochloric acid, saturated aqueous sodium hydrogen carbonate solution and brine, and then with anhydrous sodium sulfate. It was dried and subsequently concentrated under reduced pressure to precipitate crystals. The precipitated crystals were separated by filtration, washed with n-hexane and dried to give the title compound (175 g, yield 93.7%).

The results of measuring the physical properties of this compound are shown below. The NMR spectrum was measured using TMS as an internal standard and is shown by the following symbols.

s: singlet d: doublet m: multiplet J: coupling constant ¹ H-NMR (CDCl ₃ ): δ1.33 to 2.83 (m, 6H), 3.12 (s, 2
H), 3.70 (s, 3H), 7.03 (d, 2H, J = 8Hz), 7.25 (d, 2
H, J = 8Hz) mp 77.79 ℃ IR (KBr): ν _max 2940, 2900, 1710, 1438, 1200, 117
0, 1000, 854, 830 cm ^-1 (2) Synthesis of methyl 3- (4-chlorobenzyl) -2-oxocyclopentanecarboxylate 1- (4-chlorobenzyl) -2-obtained in (1)
175 g of methyl oxocyclopentanecarboxylate was dissolved in 500 ml of anhydrous methanol, 150 g of sodium methylate (28% methanol solution) was added, and the mixture was heated under reflux for 5 hours. After 300 ml of methanol was distilled off from the obtained reaction mixture, toluene was added and the methanol was azeotropically removed. After removing methanol, 300 ml of 1N hydrochloric acid was added to the toluene solution for neutralization, 500 ml of chloroform was added for extraction, the organic layer was separated, and the organic layer was washed with a saturated aqueous sodium hydrogen carbonate solution and brine, followed by And dried over anhydrous sodium sulfate,
It was concentrated under reduced pressure. The precipitated crystals were separated by filtration and recrystallized from a mixed solvent of n-hexane-ethyl acetate to give 162.3 g of the title compound.
(Yield 92.7%) was obtained.

The results of measuring the physical properties of this compound are shown below. ¹ H-NMR (CDCl ₃ ): δ1.33 to 3.33 (m, 8H), 3.76 (s, 3
H), 7.06 (d, 2H, J = 9Hz), 7.30 (d, 2H, J = 9Hz) mp 80 to 90 ° C IR (KBr): ν _max 2970, 2930, 2850, 1730, 1700, 148
0, 1430, 1336, 1258, 1190, 1120, 880, 850, 821cm ^-1 (3) Synthesis of 2- (4-chlorobenzyl) -5- (2-fluoroethyl) cyclopentanone Hydrogenated to 200 ml of anhydrous dimethylformamide 18.3 g (0.45 mol) of sodium (60% oily sodium hydride washed with anhydrous hexane) was added, and 3- (4-chlorobenzyl) -2 obtained in (2) was stirred with ice cooling. −
A solution prepared by dissolving 100 g (0.375 mol) of methyl oxocyclopentanecarboxylate in 50 ml of dimethylformamide was added dropwise. The mixture was stirred at room temperature for 40 minutes, 57.1 g (0.45 mol) of 1-bromo-2-fluoroethane was added, and the mixture was stirred at room temperature for 1 hour, then heated to 50 ° C. and stirred for 5 hours. The obtained reaction solution was extracted with ethyl acetate to obtain an organic layer, and the organic layer was washed with 1N hydrochloric acid, an aqueous solution of sodium hydrogen carbonate and brine, and dried over anhydrous sodium sulfate,
After concentration under reduced pressure, 124.1 g of methyl 3- (4-chlorobenzyl) -1- (2-fluoroethyl) -2-oxocyclopentanecarboxylate was obtained as a yellow oily substance.

Next, 200 ml of acetic acid and 200 ml of 47% hydrobromic acid aqueous solution were added to this oily substance, and the mixture was heated to 100 ° C. in an oil bath and stirred for 3 hours. After cooling the obtained reaction liquid, it was poured into ice water and n-
The organic layer was obtained by extraction with hexane, and the organic layer was washed with an aqueous sodium hydrogen carbonate solution and brine. After drying over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure to give a red oil 8
3.1 g was obtained. This oily substance was purified by silica gel column chromatography to obtain 78.6 g (yield: 82.1 g) of the title compound.
%). The physical properties of this compound are as follows. ¹ H-NMR (CDCl ₃ ): δ 1.10 to 3.27 (m, 10H), 4.51 (dt,
2H, J = 48Hz and 6Hz), 7.07 (d, 2H, J = 8Hz), 7.25
(D, 2H, J = 8Hz) IR (KBr): ν _max 2940, 2850, 1722, 1482, 1150, 108
6, 1010, 832, 800cm ^-1 MS (70ev): M / Z 254 (M ⁺ , 32%) 256 (M ⁺ + 2,8%) 207 (1
6%), 209 (5%), 125 (100%), 127 (33%) (4) 4- (4-chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane 5.2 g (0.13 mol) of sodium hydride (60% oily sodium hydride washed with anhydrous hexane) was added to 100 ml of anhydrous dimethyl sulfoxide, and 28.6 g (0.13 mol) of trimethylsulfosonium iodide was added thereto while stirring at room temperature. Mol) was added. After stirring at room temperature for 1 hour, a solution of 25.5 g (0.1 mol) of 2- (4-chlorobenzyl) -5- (2-fluoroethyl) cyclopentanone obtained in (3) in 50 ml of dimethyl sulfoxide was added dropwise. Stir for 4 hours.

The obtained reaction solution was poured into ice water, extracted with n-hexane to obtain an organic layer, and the organic layer was washed with brine. After drying over anhydrous sodium sulfate, the solvent was distilled off under reduced pressure to obtain 20.2 g of a colorless oily substance. The oil was purified by silica gel column chromatography to give the title compound 12.7
g (yield 47.3%) was obtained. ¹ H-NMR (CDCl ₃ ): δ1.02 to 2.88 (m, 10H), 2.65 (s, 2
H), 4.38 (dt, 2H, J = 48Hz and 6Hz), 6.98 (d, 2H, J =
8Hz), 7.16 (d, 2H, J = 8Hz) IR (KBr): ν _max 2940, 2852, 1714, 1482, 1090, 101
0, 832, 800cm ^-1 MS (70ev): M / Z 268 (M ⁺ , 3.5%), 270 (M ^{+ +} 2,1.1
%), 237 (24%), 239 (8%), 125 (100%), 127
(35%) (5) 6- (4-chlorobenzyl) -3,3a, 4,5,6,6a-
Hexahydro-6a- (1H-1,2,4-triazole-1
Synthesis of -ylmethyl) -2H-cyclopenta [b] furan To 100 ml of anhydrous dimethylformamide, 2.3 g (0.0575 mol) of sodium hydride (60% oily sodium hydride washed with anhydrous hexane) was added with stirring, then , With this 1H-1,2,4-triazole 4g (0.0579mol)
Was added, and the mixture was stirred at room temperature until foaming stopped. To the resulting solution was added 4- (4-chlorobenzyl) -7- (2-fluoroethyl) -1-oxaspiro [2.4] heptane 10.2 g (0.
038 mol) was added, and the mixture was stirred at room temperature for 2 hours and then heated to 50 ° C. and stirred for 2 hours.

The obtained reaction solution was allowed to cool, then poured into ice water, extracted with ethyl acetate to obtain an organic layer, the organic layer was washed with water, dried over anhydrous sodium sulfate, and then the solvent was distilled off under reduced pressure. did. The obtained residue was purified by silica gel column chromatography to give the title compound (6.26 g, yield 52%).

The physical properties of the obtained compound are as follows. ¹ H-NMR (CDCl ₃ ): δ1.04 to 2.08 (m, 7H), 2.35 to 3.08
(M, 3H), 3.15 to 3.91 (m, 2H), 4.08 (s, 2H), 7.08
(D, 2H, J = 8Hz), 7.28 (d, 2H, J = 8Hz), 7.91 (s, 1
H), 8.05 (s, 1H) IR (KBr): ν _max 2930, 2850, 1480, 1440, 1264, 120
0, 1130, 1080, 1040, 1008, 862, 836, 780, 750, 662
cm ^-1 MS (70ev): M / Z 317 (M ⁺ , 18%), 319 (M ^{+ +} 2.5%), 24
8 (20%), 250 (7.5%), 125 (100%), 127 (35%) Next, the above 6- (4-chlorobenzyl) -3,3a, 4,5,
Agriculture and horticulture containing 6,6a-hexahydro-6a- (1H-1,2,4-triazol-1-ylmethyl) -2H-cyclopenta [b] furan (hereinafter referred to as "the compound of the present invention") as an active ingredient Formulations of germicides for pathogens and test examples for controlling pathogenic bacteria are shown below.

The compound of the present invention is advantageously used as an agricultural / horticultural fungicide in the form of powder, wettable powder, granules, emulsion or liquid, etc. as it is or as a mixture with a carrier (diluent).

If necessary, a spreading agent for the agricultural / horticultural germicide of the present invention,
Needless to say, the effect can be ensured by adding an auxiliary agent such as an emulsifier, a wetting agent, or a fixing agent.

Next, some examples will be shown to prove the effectiveness of the compound of the present invention, but the carrier (diluent) and auxiliary agent, the mixing ratio thereof and the active ingredient can be varied within a wide range.

Example 2 Dust: Part by weight The compound of the present invention 3 Clay 40 Talc 57 is pulverized and mixed and used as a dusting powder.

Example 3 Wettable powder: parts by weight Compound of the present invention 50 Lignin sulfonate 5 Alkyl sulfonate 3 Diatomaceous earth 42 is ground and mixed to obtain a wettable powder, which is diluted with water before use.

Example 4 Powder: parts by weight Compound of the present invention 5 Bentonite 43 Clay 45 Lignin sulfonate 7 is uniformly mixed, water is further added and kneaded, and the mixture is processed into granules by an extrusion type granulator and dried to obtain granules.

Example 5 Emulsion: parts by weight Compound of the present invention 20 Polyoxyethylene alkyl allyl ether 10 Polyoxyethylene sorbitan monolaurate 3 Xylene 67 are uniformly mixed and dissolved to prepare an emulsion.

Example 6 Wheat powdery mildew control effect test: 2nd leaf stage seedling wheat cultivated in a clay pot with a diameter of 10 cm (cultivar; Norin No. 64, 16 plants / pot, 3 pots / treatment group used)
In addition, the wettable powder form of Example 3 was used at a predetermined concentration (125 p
pm) was diluted and suspended with water, and 5 ml was sprayed per pot. After air-spraying of the sprayed leaves, a suspension of wheat powdery mildew spores collected from the diseased leaves was spray-inoculated, kept at 20 to 24 ° C. under high humidity for 24 hours, and then left in a greenhouse. On the 9th to 11th day after the inoculation, the lesion area ratio of wheat powdery mildew was investigated, and the control value calculated by the following formula was 100%.

Example 7 Cucumber Powdery Mildew Control Effect Test Example 3 was applied to the cucumber (cultivar; Sagamihanjiro, 1 / pot, 3 pots / treatment group) when the second true leaf was cultivated in a biscuit pot with a diameter of 10 cm. Predetermined concentration (125ppm) of wettable powder form such as
Was diluted and suspended with water and sprayed in an amount of 5 ml per pot. After air-drying the sprayed leaves, spores were sprinkled on the diseased leaves with a brush to inoculate them, and the disease was caused in a glass greenhouse. The lesion area ratio of cucumber powdery mildew was examined 9 to 11 days after the inoculation, and the control value calculated by the following formula was 100%.

Example 8 Test for controlling green mold disease of kidney bean A predetermined concentration of the wettable powder form as in Example 3 was applied to the kidney bean leaves (cultivar; at the time of money) at the time of the first true leaf cultivated in a clay pot having a diameter of 10 cm. (500ppm) diluted with water and suspended, 5m per pot
l sprayed. After air-drying the sprayed leaves, a circular section (diameter 4 mm) of gray mold fungus-containing agar, which had been pre-cultured for 3 days at 20 ° C using sugar-added potato decoction agar, was directly attached to the center of the leaf. It was kept under high humidity conditions at 22 ° C. On the third day after inoculation, the lesion area ratio of green bean mildew was investigated, and the control value calculated by the following formula was 100%.

Example 9 Wheat leaf rust control test The seedling wheat of the second leaf stage (cultivar; Norin No. 64, 16 plants / pot) cultivated in a biscuit pot with a diameter of 10 cm had the wettable powder form shown in Example 3. The product was diluted with water to a predetermined concentration (125 ppm) with water, and the suspension was sprayed at a rate of 5 ml / pot. After air-drying the sprayed leaves, a suspension of the spores of wheat leaf rust fungus collected from the diseased leaves was spray-inoculated and kept under high humidity at 20-23 ° C for 24 hours. After that, it was left in a glass greenhouse, and 7 to 10 days after the inoculation, the lesion area ratio of wheat leaf rust was investigated, and the control value calculated by the following formula was 100%.

Example 10 Antibacterial Test Against Various Pathogenic Bacteria This example shows the results of testing the antibacterial activity of the 2H-cyclopenta [b] furan derivative according to the present invention against various plant pathogenic bacteria.

Test method: The compound of the present invention was adjusted to a predetermined concentration (100 ppm),
Dissolve in Dimethyl Sulfoxide, mix 0.6 ml of it with 60 ml of PSA medium at 60 ° C well in a 100 ml Erlenmeyer flask,
It was poured into a jar and solidified. On the other hand, test bacteria previously cultured on a plate medium were punched out with a cork borer having a diameter of 4 mm, and inoculated on the above-mentioned drug-containing plate medium. After inoculation, the cells were cultured for 1 to 3 days at a suitable growth temperature. The growth of the fungus was measured by the diameter of the fungus, and compared with the growth of the fungus in the non-agent-added area, the rate of inhibiting hyphal elongation was calculated according to the following formula.

R = (dc-dt) 100 / dc where R = hyphal elongation inhibition rate (%) dc = untreated plate diameter of fungal cells dt = drug treated plate diameter of bacterial cells.

The results were evaluated according to the following criteria and classified into 5 grades and shown in the table.

Growth inhibition rate 5 Hyphal elongation inhibition rate of 100 to 90% 4 Hyphal elongation inhibition rate of 89 to 70% 3 Hyphal elongation inhibition rate of 69 to 40% 2 Hyphal elongation inhibition rate of 39 to 20% Thing 1 The hyphal elongation inhibition rate is 19% or less

[Brief description of the drawings]

The attached FIGS. 1 and 2 show 6- (4-chlorobenzyl) -3,3a, 4,5,6,6a-hexahydro-6a- (1H-1,
The infrared absorption spectrum and NMR spectrum of 2,4-triazol-1-ylmethyl) -2H-cyclopenta [b] furan are shown in FIG. 3, and methyl 3- (4-chlorobenzyl) -2-oxocyclopentanocarboxylate is used. FIG. 4 shows the NMR spectrum of 2- (4-chlorobenzyl) -5- (2-
Fluoroethyl) cyclopentanone NMR spectrum,
And FIG. 5 shows 4- (4-chlorobenzyl) -7- (2-
Fluoroethyl) -1-oxaspiro [2.4] heptane N
Each MR spectrum is shown.

Claims (6)

(57) [Claims] 1. 6- (4-represented by the following chemical formula (1)
Chlorobenzyl) -3,3a, 4,5,6,6a-hexahydro-6
a- (1H-1,2,4-triazol-1-ylmethyl) -2H
-Cyclopenta [b] furan. 2. 4- (4-chlorobenzyl) -7- (2-
Fluoroethyl) -1-oxaspiro [2.4] heptane and
A method for producing a 2H-cyclopenta [b] furan derivative represented by the above formula (1), which comprises reacting with 1,2,4-triazole. 3. A fungicide for agricultural and horticultural use containing a 2H-cyclopenta [b] furan derivative represented by the above formula (1) as an active ingredient. 4. An intermediate for producing a 2H-cyclopenta [b] furan derivative represented by the above formula (1).
-(4-chlorobenzyl) -7- (2-fluoroethyl)
-1-Oxaspiro [2.4] heptane. 5. An intermediate 2 for producing a 2H-cyclopenta [b] furan derivative represented by the above formula (1).
-(4-chlorobenzyl) -5- (2-fluoroethyl)
-Cyclopentanone. 6. An intermediate for producing a 2H-cyclopenta [b] furan derivative represented by the above formula (1).
Methyl-(4-chlorobenzyl) -2-oxocyclopentanecarboxylate.