CS259592B1 - Fungls / Days Agent - Google Patents

Abstract

The solution relates to a new fungicidal composition which contains as an active substance a derivative of kojic acid of the general formula I, where Ri means the group —CH2—Cl, —CH2—J, or —CH2—Br. The bromine derivative has the greatest and broadest fungicidal effect. The active substances can be used as a concentrate, solution, emulsion, suspension, powder, paste or granulate. These compositions are prepared by known methods. The compounds according to the invention can be used in the protection of agricultural crops, in particular against phytopathogenic phycomycetes, micromycetes from the genera Alternaria sp., Botrytis sp., Fusarium sp., Tilletia foetida and Tilletia carries. In addition, the fungicidal composition based on the active substances can be used in therapy against pathogenic micromycetes in the field of human and veterinary medicine.

Description

The invention relates to a fungicidal composition which contains a halogen derivative of kojic acid as an active ingredient.

Numerous groups of organic compounds suitable as fungicides are known from literature and practice. These include:

carbamates, isocarbamates, alkylene-bis-dithiocarbamidates, thiurams, amides, dicarboximides, diazines, triazoles, quinolines and others.

(List of permitted plant protection products 1986, Pesticide Manual 1985), used in practical plant protection and, for example, groups of compounds based on imidazole derivatives, undecyl acid derivatives, mucidin, clotrimazole, nystatin, hexachlorophene, etc. used in dermatology.

No fungicidal agents based on kojic acid are known to date. Kojic acid itself does not have fungicidal effects. However, it is a substance of bioorganic origin, perfectly degradable, without adverse effects on individual components of the biocenosis.

The current global trend in the field of research into new fungicides is primarily focused on substances that, in addition to their fungicidal effect, do not contribute to the disruption of the ecosystem.

In this context, it has been found that kojic acid derivatives of the general formula

where

R1 means —CH2Cl, —CH2J or —CH2Br are characterized by fungicidal effects. The synthesis of kojic acid derivatives can be carried out by various methods, which are described, for example. (F. Kipnis, H. Soloway, J. Ornfelt, J. Amer. Chem. Soc. 75, 1953, page >3608; Takashi Kotani, Itsko Ichimoto, Chuji Tatsumi: J. Fermet. Technol. 51, 1973, page 66, G. Choux, R. L. Benoit: J. Org. Chem. 32, 1967, page 3974).

The active substances according to the invention are distinguished from most of the fungicides used in that, in addition to excellent fungicidal effects, they are of bioorganic origin and do not cause pollution of the ecosystem and have a broad spectrum of action.

The active ingredients used can be prepared into conventional formulations, such as solutions, emulsions, suspensions, powders, foams, pastes, granules, aerosols, natural and synthetic substances impregnated with active ingredients, etc. These formulations are prepared by known methods, for example by mixing the active ingredient with excipients, such as liquid solvents, solid carriers, or by using surface-active agents, such as emulsifiers, dispersants and thickeners. When water is used as a solvent, organic solvents can also be used as an auxiliary solvent.

Suitable liquid solvents include, in particular, aromatics such as xylene, toluene, chlorinated aromatics or chlorinated aliphatic hydrocarbons, for example chlorobenzenes, chloroethylenes, alcohols such as methanol and glycol, strong polar solvents such as dimethylformamide and dimethylsulfoxide, and water.

Solid carriers used include, for example, kaolin, alumina, talc, chalk, highly dispersed silicic acid and silicates. Emulsifiers can be nonionic or anionic, for example, polyoxyethyl esters of fatty acids, polyoxyethylene ethers such as alkylaryl polyglycol ethers, alkyl sulfonates and aryl sulfonates. Dispersants include, for example, lignin, sulfite liquor and methyl cellulose.

The active ingredients can be used in the respective compositions in admixture with other known active ingredients.

The compounds according to the invention can be used either in the form of concentrates or as solutions, emulsions, suspensions, powders, pastes and granules. They can be applied by spraying, dipping, pouring, incorporation into the soil, to the above-ground or underground parts of plants and seeds, or to inanimate substrates and the like.

The fungicidal compositions according to the invention can be used in the protection of agricultural crops, especially against phytopathogenic phytomycetes, micromycetes from the genera Alternaria sp., Botrytis sp., Fusarium sp., Tilletia foetida and Tilletia carries. In addition, fungicidal compositions based on active substances can be used in therapy against pathogenic micromycetes in the field of human and veterinary medicine. Their use is expected in the fight against microbial corrosion, in the protection of wood, textiles, paper, etc. Example 1

Preparation of kojic acid as a starting material

On a liquid nutrient medium containing assimilable carbon, nitrogen and nutrient salts, the strain Aspergillus tamarii mutant VIII (CCM F — 781) or Aspergillus tamarii mutant III (CCM F — 780) is cultivated individually, . ‘ . . . -uA..i.£á or in a mixture, and kojic acid is isolated by concentrating the ultrafiltered medium with subsequent crystallization. Kojic acid is obtained in an extract of 35 g per 100 g of sugar.

Example 2

Preparation of chlorochoic acid (2-chloromethyl-5-hydroxy-4-pyrone

0.01 mole (1.42 g) of kojic acid is mixed in 15 ml of chloroform with 0.02 mole (2.4 g) of freshly distilled SOC12 sulfuric acid dichloride and refluxed for 1 hour. After cooling, the precipitate formed is filtered off with suction and recrystallized from water. Yield 85 percent, m.p. 185 °C. Prepared according to F. Kipnis, H. Soloway, J. Ornfelt, J. Amer. Chem. Soc. 70, 4 264 (1948).

Example 3

Preparation of iodoic acid (2-iodomethyl-5-hydroxy-4-pyrone)

0.015 mol (2.5 g) of chlorokoic acid is dissolved in 20 ml of acetone and mixed with 0.015 mol (2.2 g) of sodium iodide dissolved in acetone while shaking. The reaction mixture is stirred for half an hour, the precipitate formed is filtered off with suction and the residue is concentrated in vacuo. It is crystallized from ethanol. The yield of iodokoic acid is 1.8 g (49%; melting point 180-181 °C). Prepared according to the literature: G. Choux, R. L. Benoit: J. Org. Chem. 32, 3974 (1967).

Example 4

Preparation of bromokoic acid (2-bromomethyl-5-hydroxy-4-pyrone j

0.02 mole (2.84 g) of kojic acid is dissolved in 6 ml of concentrated sulfuric acid and 6 ml of 48% hydrobromic acid are added while cooling with ice. The reaction mixture is heated for 2 to 3 hours at 70 °C and poured onto ice while hot. The precipitated crystals are recrystallized from ethanol. The yield is 45%. Melting point 180-183 °C.

Prepared by Takashi Kotani, Itsko Ichimoto, Chuji Tatsumi: J. Ferment. Technol. 51, 66 (1973).

Example 5

Determination of antifungal activity on Phytophthora investans, Botrytis cinerea, Fusarium nivale, Alternaria solani by diffusion method on agar plates δ

On a sterile paper disc (Whatman No 1), 0 10 mm, 1Ó μΐ of a 1% solution of the test compound in a suitable volatile organic solvent is applied. After evaporation of the solvent, the disc is placed in the center of a sterile Petri dish 0 100 mm and covered with a suspension of spores of the tested organism in an optimal nutrient agar medium in a ratio of 1:4 (2.5 ml aqueous suspension of spores from a 21-day culture: 10 ml nutrient medium /45 °C/j. After the nutrient medium solidifies, the Petri dishes are placed in a thermostat and the micromycete cultures are incubated at the optimal growth temperature (Alternaria solani, Botrytis cinerea — — 24 °C, Fusarium nivale — 21 °C, Phytophora iniestans — 17 °C for the first 24 hours, subsequent incubation — 20 °C). The test includes the inclusion of a standard commercial preparation as one of the variants — the effectiveness of the standard represents the objectivity of the test.

The antifungal activity of the compound was demonstrated by the formation of a sterile inhibition zone formed by the sensitive test organism around the center of diffusion.

formation of a sterile inhibition zone _; -j(antifungal active substances) zone does not form — (substances without antifungal activity]

Example 6

Determination of antifungal activity on Tilletia foetida by diffusion method

Petri dishes 0 100 mm are filled with 40 g of finely sieved and sterilized soil (loamy-sandy sieved on a sieve with 0 mesh 2 mm). The soil is leveled and moistened using an atomizer at a pressure of 0.08 MPa with sterile distilled water (17 ml). The surface of the soil is inoculated with an aqueous suspension of chlamydospores of Tilletia foetida (1.5 ml/1 Petri dish) using an atomizer. 100 μΐ of a 0.1 percent aqueous suspension or emulsion of the test compound is applied to the center of the Petri dish, on the surface of the soil. After a 10-day incubation at 10 °C, the activity of the compound is determined, which is manifested by the formation of a sterile inhibition zone around the center of diffusion.

Preparation of chlamydospore suspension:

Individual grains are separated from ears infected with Tillotia foetida, crushed in a mortar and sieved through a sieve (0 mesh 0.5 mm). The obtained chlamydospores are thoroughly mixed in a homogenizer with sterile distilled water (1 g chlamydospores + 15 ml Ή2Ο), the suspension thus prepared is used for soil inoculation.

,25 9 5 3 2

Table 1

Qualitative determination of effectiveness

Active ingredient (amount of active ingredient 100 µg/disk)

Antifungal efficacy of Phyto-Alterna-Botrytis phtora ria so-cienerea infestans lani

Fusa- Tilletia rium foetida sol ani

R

kojic acid --CH2OH — chlorochoic acid —CH2C1+ — iodokoic acid —CH2J + bromoconic acid —CH2Br +

Dithane M-45,+ +

+ + + mancozeb complex of maneb and Zn ions maneb-ethylene-1,2-ti -bis-dithiocarbamidate « manganese -Ια Euparen (dichlorofluanid] .o, N,N-dimethylN'-dichlorofluoromethylthiog -N'-phenylsulfamide — o Fundazol 50 WP (benomyl)

1-(N-butylcarbamoyl)-2-methoxycarboxamidobenzimidazole — ⁺ some degree of effect is only at a dose of 100 µg/disk

Example 7

Quantitative determination of antifungal activity against Phytophtora inestans, Botrytis cinerea, Alternaria solani and Fusarium nivale in vitro

To 13.5 ml of nutrient agar medium (45 degrees Celsius) is added 1.5 ml of aqueous emulsion or suspension of the tested compound in graded concentrations of the active substance. After thorough mixing, the homogenate is poured into Petri dishes 0 100 mm. After the nutrient medium has solidified, a fungal inoculum 0 10 mm, cut from the edge of a growing colony of the respective micromycete, is placed in its center. Incubation is carried out in a thermostat at the optimal temperature for the growth of the micromycete. The growth of the model micromycete is periodically monitored at different concentrations of the active substance in the medium.

The criterion for antifungal activity is the inhibition of radial growth of a fungal colony relative to the growth of the fungus on a nutrient medium in the absence of the inhibitor.

To calculate biological efficacy we use Abbott's relationship

U = * = 100

K

U = biological efficiency (% j

K = 0 micromycete colonies without inhibitor in nutrient medium

F = 0 micromycete colonies with inhibitor in nutrient medium

Table 2

Quantitative determination of efficacy

Model organism Concentration of active substance in the medium (^g. ml“ ¹ ) Biological efficiency (%) iodokoic acid Dithane M-45 Phytophthora infestans 50 100 100 10 100 100 1 13.3 28.8 0.1 6.6 20 Alternaria solani 100 26 42 50 16 30 10 8 12 Eupharn Botrytis cinerea 100 100 100 50 13.3 72 10 8 48 1 6.6 28 Fundazol WP 50 Fusarium nivale 100 47 100 50 28 100 10 23 72 5 6 38 Model Concentration Biological efficiency (%) organism active substance in the medium (^g.ml ^-1 ) Bromokoic acid Dithane M-45 Phytophthora infestans 100 100 100 50 100 100 10 100 76.6 5 100 34.4 Alternaria solani 1 73.3 16 100 100 37.1 50 100 16 Botrytis cinerea 10 7.1 10 Eupharn 50 70 73.8 10 22.4 63.5 5 0 37.5 Fundazol Fusarium nivale 100 100 100 50 45 100 10 19 55 5 14 26

Example 8

Determination of efficacy against Phytophtora infestans in vivo on tomatoes

Tomatoes of the "Imun" variety are sprayed with an aqueous suspension or emulsion of the tested compounds in graded concentrations of the active substance, using an atomizer at a pressure of 0.08 MPa in a spray box with a rotating plate — 10 ml of spray liquid/3 plants. (For testing, plants grown to the 5-leaf stage after decapitation and removal of the first 2 leaves according to the genetic spiral are used.)

After 2 hours, the sprayed plants are inoculated with an aqueous suspension of Phytophtora infestans zoospores — 4.5 ml/3 plants — using an atomizer. The infected plants are incubated in a climate-controlled booth at a temperature of 18 degrees Celsius + 1 °C and RVV = 100%, under glass or polyvinyl chloride insulators.

Antifungal efficacy is evaluated 6 days after inoculation at the time when untreated control plants are 75 to 100% infected with the pathogen according to the following scale:

Class

About

252592

Infested leaf area (%) P = infestation index n = number of leaves in the respective class 0 v = attack class 5 N = total number of leaves 10 5 = highest attack class 15 25 The antifungal activity (U) is evaluated 50 and over according to Abbott's formula

(P) is calculated from the obtained -Heuberger values:

according to Townsend attack index (n^v)_

Ò u = K-_L_. _lo0 K

K — infestation index of control untreated plants

P — attack index of plants treated with the test compound

Table 3

Biological activity of bromocouic acid after foliar spray application — Phytophtora infestans. Solanum lycopersicum (tomato)

Preparation Concentration of active substance (,/g . ml ¹ ) Biological efficiency (%) Dithane M-45 1,000 100.0 465 95.5 216 100.0 Kuprikol 50 1,000 98.3 (Cu oxychloride) 465 95.2 basic CuCl2 216 88.2 Bromokoic acid 1000 92.3 465 91.8 216 87.4 Control untreated plants — 0 Table 4 Biological efficacy of iodocoic acid after foliar spray application — Phytophtora infes- tans: Solanum lycopersicum Preparation Concentration of active ingredient Biological efficiency (°/o) (fig. ml ¹ ) Dithane M-45 1,000 100 465 100 216 96 Iodokoic acid 1000 88 465 68 216 60

Control untreated plants

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Example 9

Determination of antifungal efficacy against Phytophtora infestans in vivo on potatoes (Solanum tuberosum)

Potatoes — variety "Radka" grown in Mitscherlich containers to the stage T a b u 1' k a 5 of a perfectly developed bunch (height approx. 45 cm) were sprayed with an aqueous suspension of the test compounds using an atomizer at a pressure of 0.08 MPa (50 ml of spray liquid//potato bunch). The method of inoculation (amount of inoculum increased proportionally to biomass), incubation and method of evaluating the effectiveness were used as in Example 8.

Biological activity of the compound bromokoic acid after foliar spray application — Phytophtora infestans: Solanum tuberosum (potato).

Preparation Concentration Biological activity of the active substance (%) (µg. ml“ ¹ )

Dithan 1000 M — 45 465 standard 216 100 Cupricol 1000 50 465 standard 216 100 Acid 1000 bromide 465 216 100

Control untreated plants

Example 10 parts by weight of the active substance are dissolved in a mixture consisting of 75 parts by weight of xylene and dimethylformamide in a ratio of 1:1 and 5 parts by weight of emulsifier (Emulsogen) are added. By dispersing 5 parts by weight of the emulsion concentrate in 1000 parts by weight of water, a basic aqueous emulsion is obtained, which contains 1000 µg.ml ^-1 of the active substance.

Example 11

Determination of antifungal activity on Microsporum persicolor,

Microsporum langeroni,

Trichophyton mentagrophytes v. interdigital,

Trichophyton mentagrophytes v. granulosum,

Microsporum canis,

Scopulariopsis,

Trichophyton tonsurans,

Microsporum gypsum,

Trichophyton quinckeanum, Trichophyton equinum,

Trichophyton terrestris,

Microsporum cookei,

Trichophyton megninii,

Trichophyton gallinae,

Trichophyton ajelloi,

91.1

98.5

96.6 89.4

100

75.2

92.2 50.8

81.4

97.0

70.6

90.6

Emmonsia crescens,

Ctenomyces serratus,

Chrysosporium keratinophilum, Chrysosporium evolceani and Trichophyton rubrum by diffusion method on agar plates.

15 ml of hot Sabouroud's medium was added to a Petri dish with a diameter of 10 cm, which contained 20 g of agar oxide, 10 g of peptone, 40 g of glucose, 0.5 g of cycloheximide and 0.05 g of chloramphenicol in 1000 ml of distilled water. The agar gel was allowed to solidify at laboratory temperature. 1 ml of spore suspension (350,000 spores. ml- ¹ ) from a 21-day culture of the investigated fungal species in 0.9% sodium chloride was applied to the surface of the agar plate. Metal cylinders with a diameter of 6 mm and a height of 10 mm were placed on the agar plates prepared in this way, into which 0.2 ml of a solution of the active substance with a concentration of 10 ug. ml ^-1 in 1% dimethyl sulfoxide was filled. The agar plates were incubated in a thermostat at 25 °C for 72 hours. During this time, the active substance diffused from the space of the cylinders into the agar plate. The antifungal activity of the active substance was demonstrated by the formation of a sterile inhibition zone, which was formed by a sensitive test organism around the center of diffusion after 14 days of incubation in a thermostat at 25 °C.

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Table 6

Qualitatively . ml- ¹ .

determination of the efficacy of kojic acid compounds at a concentration of 10 μg.

Dermatophytes and mold fungi

Inhibition zone diameter (cm) % 1 % dimethyl sulfoxide dimethyl- Ri ' Rl Rl sulfoxide —CH2—Cl —CH2—Br — CH2—I

Microsporum percicolor 0 3.13 2.00 0 Microsporum langeroni 0 2.00 0 0 Trichophyton mentagrophytes 0 4.00 0 4.00 in, interdigitally Trichophyton mentagrophyte 0 3.00 0 2.00 phytes v. granulosum Microsporum canis 0 3.00 0 0 Scopulariopsis 0 3.00 2.25 2.50 Trichophyton tonsurans 0 2.25 0 0 Microsporum gypseum 0 2.00 4.20 0 Trichophyton quinckeanum 0 3.00 2.00 0 Trichophyton equinum 0 4.00 2.50 0 Trichophyton terrestris 0 3.25 2.50 0 Microsporum cookei 0 0 0 2.60 Trichophyton megninii 0 0 3.50 0 Trichophyton gallinae 0 3.00 2.25 0 Trichophyton, and jello 0 2.90 2.75 2.45 Emmonsia crescens 0 0 3.75 0 Ctenomyces serratus 0 2.70 0 0 Chrysosporium keratino- philum 0 3.00 0 0 Chryosporium evolceani 0 2.50 0 0 Trichophyton rubrum 0 2.00 3.00 0

The active ingredients according to the invention, for in vivo application, especially in human and veterinary medicine, are formulated as ointments, pastes, gels, aerosols, solutions, suspensions, emulsions, tablets, suppositories, soaps or powders.

Claims (1)

SUBJECT A fungicidal composition, characterized in that it contains a kojic acid derivative of the general formula as active substance OF THE INVENTION wherein R 1 is -CH 2 -Cl -CH 2 -J or -CH 2 -Br. HO Ό R, < Severography, n. p. Race 7, Most