GB2121040A - N-(2-methyl-5-chlorophenyl)- N-methoxyacetyl-3-amino-1,3-oxazolydin- 2-one and fungicide compositions - Google Patents

Abstract

N-(2-methyl-5-chlorophenyl)-N- methoxyacetyl-3-amino-1,3-oxazolydin- 2-one having the formula: <IMAGE> exhibits decidedly superior fungicidal activity than other compounds of its class. The compound has both preventative and curative action and may be applied in conventional formulations.

Description

SPECIFICATION N-(2-methyl-5-chlorophenyl)-N-methoxyacetyl-3-amino-1 ,3-oxazolydin-2-one and fungicide composition containing same This invention relates to a compound endowed with fungicidal activity and in particular to the compound N-(2-methyl-5-chlorophenyl)-N-methoxyacetyl-3-amino- 1, 3-oxazolydin-2-one and to its use in combatting fungal infections in useful plants and to fungicide compositions containing same.

Belgian Patent Specification No. 885,1 17 discloses fungicide compounds belonging to the class of N-aryl-N-acyl-3-amino-1 ,3-oxazolydin-2-ones including compounds within the general formula:

in which: R, R1 and R2 independently represent a hydrogen atom, a halogen atom or an alkyl or alkoxy group either of which contains 1 to 4 carbon atoms.

Subsequent research on such compounds has revealed that the position of substituents R, R' and R2 on the aromatic ring, is of particular importance. In particular, the compounds of formula (I) in which at least one of the ortho positions is unsubstituted are endowed with good fungicidal activity and the particular compound N-(2-methyl-5-chlorophenyl)-N-methoxyacetyl-3 amino-1 ,3-oxazolydin-2-one is surprisingly endowed with a definitely superior fungicidal activity.

Therefore according to the present invention there is provided the compound N-(2-methyl-5chloro phenyl)-N-methoxyacetyl-3-amino- 1 , 3-oxazolydin-2-one of the formula:

Compound (II) is endowed with a particularly high fungicide activity and may be used, either alone or in the form of a suitable composition, to combat fungal infection in plants of agricultural importance.

Also according to the invention there is provided a method of protecting agricultural cultivations against the attack of phytopathogenous fungi comprising administering an effective amount of compound (II) and fungicidal compositions containing compound (II) as active ingredient.

The preparation of compound (II) may be conducted according to the general reactions disclosed in Belgian Patent Specification No. 885,117. By following a process analogous to that described in said Patent and starting from 2-methyl-5-chloro-phenyl-hydrazine, compound (II) was obtained with good yields in the form of a thick oil exhibiting a refractive index at 50"C of 1,5375.

After crystallisation from ethyl acetate plus ligroin, compound (II) was obtained in the form of a white crystalline solid having a melting point of 69 to 70"C.

IR analysis (main absorption bands): 2930, 1775, 1710, 1490, 1410, 1130and and 1035 cm-1.

Compound (II) is endowed with a high fungicidal activity which is particularly effective against fungi belonging to the class of Phycomicetes.

As will be illustrated in the Examples hereinafter the fungicidal activity of compound (II) is definitely superior to that of other compounds of formula (I) in which at least one of the ortho positions of the aromatic ring is unsubstituted.

Compound (II) is perfectly compatible with the plants to be protected from the phytopathogenous fungi attack and exhibits a phyto-toxicity inferior to that of many compounds described in the above referenced Belgian Patent. Compound (II) develops both a curative as well as a preventative action and is endowed with remarkable systemic properties.

These characteristics allow compound (II) to be used both for preventing attacks to the useful cultivations and curing diseases caused therein by phytopathogenous fungi belonging particularly to the following genera: Peronospora, Phytophtora, Plasmopara, Pseudoperonospora and Pythium.

The high activity of compound (II) makes it possible to utilise very low effective dosage rates which, depending on different factors, e.g. the type of cultivation to be protected, the type and the degree of fungal infection foreseen or present, climatic (weather) factors and environmental conditions, may range from 1 to 100 g/ha.

For practical purposes it is useful to apply compound (II) in the form of suitable compositions which can be diluted with water before use. Compositions containing, as active ingredient, compound (II) may be prepared in the form of a liquid concentrate, emulsifiable concentrate, dry power or wettable powder in accordance with conventional formulative practice. Such compositions may comprise, in addition to compound (it), inert liquid or solid carriers and optionally one or more other additives, e.g. emulsifiers, surfactants, wetting agents and suspending agents.

If desired, it is possible to include in the fungicide compositions other active substances effective in the agricultural field and compatible with compound (II), e.g. herbicides, fertilizers, biostimulants and other fungicides.

In particular, it has been found that for certain types of applications the co-formulation of compound (II) together with other, so-called "coverage", fungicides is very effective. These fungicides may belong to one of the following classes: alkylene-bis-dithiocarbamates, copper salts or oxides and N-haloalkylthio-imides. Examples of such fungicides are compounds known by the following common names: Zineb, Maneb, Mancozeb, Nabam, copper oxychloride, Captan, Captafol and Folpet.

The invention will now be illustrated by the following Examples.

Example 1 Curative activity against Plasmopara viticola on vine plants.

General methodology The leaves of cv. Dolcetto vine plants, grown in pots, in a conditioned environment at 25"C and at 60% relative humidity, were besprinkled on their lower surface with an aqueous suspension of condidia of Plasmopara viticola (B. et C.) Berl et de Toni (200,000 conidia/cc).

After a residence time of 24 hours, in a humidity saturated environment at 21 "C, the plants were divided into three groups. The plants of each group were then treated, by besprinkling both leaf surfaces, with the product under examination, dissolved in a water/acetone solution (acetone = 20% by volume), respectively after 1, 2 and 3 days from the infection date.

At the completion of the incubation period (7 days), the degree of infection was evaluated according to an evaluation scale ranging from 100 (for a healthy plant) to 0 (for a completely infected plant).

The following Table 1 reports the data for the curative activity against P.viticola of compound (II) by comparison with the data of seven other compounds (A, B, C, D, E, F and G) of formula (l) From the data in Table 1 it will readily be appreciated that compound (Il) possesses a fungicidal activity that is definitely superior to that of the comparative compounds. Furthermore, the funcidical activity of compound (II) is particularly high in an absolute sense since this compound still displays a full activity (with a 100% reduction of the fungal infection) at extremely low doses (0.0005%).

Table 1 Curative activity against Plasmopara viticola on vine at the indicated doses, expressed as percentage reduction of the fungal infection Dose (in %) Compound R R1 R2 0.01 0.005 0.001 0.0005 II 2-CH3 5-CI H 100 100 100 100 A 2-CH3 H H 100 - 7 - B 3-CI H H 100 85 74 - C H H H 100 100 23 - D 3-CI 5-CI H 100 - 20 - E 3-CH3 H H 100 - 52 - F 3-F H H 100 - 15 - G 2-CI 5-CI H 100 90 70 - Example 2 Curative action against Peronospora tabacina on tobacco plants.

General methodology Leaves of tobacco plants of cv. Burley, grown in pots in a conditioned environment, were besprinkled on the lower leaf surface with an aqueous suspension of conidia of Peronospora tabacina Adam (200,000 conidia/ml). After a residence time of 6 hours in a humidity saturated environment, the tobacco plants were divided into two groups and placed in an environment conditioned at 20"C and 70% relative humidity, for the incubation of the fungus. After 24 and 48 hours respectively from the moment of the infection the treatment of the first and the second group were treated by besprinkling both leaf surfaces with the product under examination in a water/acetone solution (acetone = 20% by volume).At the end of the incubation period (6 days) the degree of infection was evaluated according to an evaluation scale ranging from 100 (for a healthy plant) to 0 (for a completely infected plant).

The following Table 2 reports the data for the curative activity against P. tabacina of compound (II) in comparison with seven other compounds of formula (I) (A to G).

From the data in Table 2 it will be readily appreciated that compound (II) possesses a fungicide activity which is decidedly superior to that of the comparative compounds and that the fungicidal activity of compound (II) is extremely high in an absolute sense, in as much as a complete activity (100% reduction of the fungal infection) at very low doses (0.0005%).

Table 2 Curative action against Peronospora tabacina at the indicated doses expressed as a percentage reduction of the fungal activity.

Dose (in %) Compound R R' R2 0.01 0.005 0.001 0.0005 II 2-CH3 5-CI H 100 100 100 100 A 2-CH3 H H 100 100 47 - B 3-CI H H 100 100 92 68 C H H H 100 74 0 - D 3-CI 5-CI H 100 - 30 - E 3-CH3 H H 100 - 60 - F 3-F H H 100 - 30 - G 2-CI 5-CI H 100 100 75 - Example 3 Preventive action against Plasmopara viticola on vine.

General methodology The vine leaves of cv. Dolcetto, grown in pots in a conditioned environment, were besprinkled on the upper leaf surface with the product under examination dissolved in a water/acetone solution at 20% of acetone (vol./vol.).

The plants were then placed in a conditioned environment. Two series of plants were separately besprinkled on their lower leaf surfaces, 1 and 7 days from the day of treatment respectively, with an aqueous suspension of Plasmopara viticola conidia (200,000 conidia/cc) and, after 24 hours residence time in humidity saturated environment, were placed back in a conditioned environment.

At the end of the incubation period (7 days) the degree of infection was assessed. Compound (II) displayed a preventive action superior to that of the comparative compounds used in Example 1. Furthermore, the preventive activity against Plasmopara viticola of compound (II) proved to be extremely high in an absolute sense in as much as at very low doses (0.0005%) compound (II) was able to completely inhibit fungal infection both when the artificial infection was conducted 1 day and 7 days following teatment with compound (II).

Example 4 Preventive activity against Peronospora tabacina on tobacco.

General methodology cv. Burley tobacco plants grown in pots in a conditioned environment, were treated by besprinkling both leaf surfaces with the product under examination in a water/acetone solution at 20% acetone (vol./vol.). Two series of plants were treated respectively after 1 and 7 days, by besprinkling the lower leaf surface with an aqueous suspension of Peronosporo tabacina Adam conidia (200,000 conidia/cc). After 6 hours dwell time in a humidity saturated environment, the treated plants were placed in an environment conditioned at 20"C and 70% relative humidity for the incubation of the fungus.

At the end of the incubation period (6 days), the degree of infection was assessed. Compound (II) exhibited a fungicide activity decidedly superior to that of the comparative compounds used in Example 1. Furthermore, the preventive activity against Peronospora tabacina of compound (II) is extremely high in an absolute sense in as much as, even when used in very low doses (i.e.

0.0005%), the compound is able to completely inhibit fungal infection both when the artificial infection is conducted 1 day and 7 days following the treatment with compound (II).

The following Examples relate to fungicidal compositions containing as active ingredient compound (II) alone or compound (Il) in association with Mancozeb (zinc and manganese ethylene-bis-dithiocarbamate) .

In these Examples the following abbreviations will be used: DMF = N,N-dimethyl-formamide.

Xylene = commercially available mixture of xylene isomers.

Ca-DBS = calcium dodecylbenzenesulphonate, e.g. the product marketed by ROL-Montedison under the trade name "Emulson AG/CaL".

COH-ETO = polyoxyethylated hydrogenated castor oil, e.g. the product marketed by ROL Montedison under the trade name "Emulson Coy".

SO-ETO = polyoxyethylated sorbitan-oleate, e.g. the product marketed by ROL-Montedison under the trade name "Emulson 20-OM".

NF-ETO = polyoxyethylated nonylphenol, e.g. the product marketed by ROL-Montedison under the trade name Emulson 1 OB".

Na-DSS = sodium dialkylsulphosuccinate, e.g. the product marketed by ROL-Montedison under the trade name "Madeol V40".

Na-LS = sodium lignosulphonate, e.g. the product marketed by Borregard under the trade name "Ultrazina NA' and the product marketed by Cartiere di Tolmezzo under the trade name "Bretax".

Na-NS = sodium alkylnaphthalensulphonate, e.g. the products marketed by ROL-Montedison under the tradenames "Madeol W90" and "Madeol 934".

Example 5 Compositions in emulsifiable concentrate (EC Ingredients (by weight): A) Compound (Il) 5 to 40% B) Solvent 40 to 90% C) Surfactant 5 to 20% Suitable solvents (BB are aromatic and alkyl-aromatic hydrocarbons, ketones, esters, DMF and mixtures thereof.

Suitable surfactants (C) are polyoxyethylated nonylphenol, polyoxyethylated triglycerides, polyoxyethylated fatty acids, sodium, calcium or triethanolammonium dodecylbenzensulphonate and mixtures thereof.

The preparation of the compositions is effected by dissolving compound (II) in the solvent and then admixing the surfactant. Examples of compositions in emulsifiable concentrate are reported in the following Table 3.

Table 3 Compositions in emulsifiable concentrate (ingredients in percent by weight) Compositions Ingredients 1 2 3 4 5 A) Compound (II) 20 5 15 30 40 B) Xylene 63 90 70 40 40 B) Cyclohexanone 7 - - 10 B) DMF 3 - 3 - 10 C) Ca-DBS 3 1 2.5 4 3 C) COH-ETO 3.5 - - 6 - C) SO-ETO - 4 4.5 - 3 C) NF-ETO 3.5 - 5 10 4 Example 6 Compositions in wettable powder (WP) Ingredients (by weight): A) Compound (II) 5 to 50% B) Wetting Agent 0.5 to 5% C) Suspending Agent 1 to 5% D) Carrier 40 to 93.5% Suitable wetting agents (B) are polyoxyethylated nonylphenol, sodium alkylnaphthalensulphonate, sodium dialkylsulphosuccinate and mixtures thereof.

Suitable suspending agents (C) are sodium, calcium or aluminum lignosulphonate, sodium alkylnaphthalenesulphonate condensed with formaldehyde, maleic anhydride diisobutylene copolymers and mixtures thereof.

Suitable carriers (D) are fossil meal (diatomaceous earth), kaolin, CaCO3, SiO2 and mixtures thereof.

The preparation of the compositions in wettable powder is carried out by grinding in a suitable mill the mixture of the ingredients to the established particle size.

The following Table 4 reports examples of compositions in wettable powder.

Table 4 Compositions in wettable powder (ingredients in percent by weight).

Compositions Ingredients 1 2 3 4 5 6 A) Compound (II) 25 5 15 30 40 50 B) Na-DSS 2 - - 1 2 B) Na-NS - 1 4 - 2 B) NF-ETO - - - - - 5 C) Na-LS 3 2 1 3 2 5 D) Kaolin 70 92 60 61 - 10 D) Fossil meal - - 20 - 44 D) Si02 - - - 5 10 30 Example 7 Compositions in wettable powder of Compound (II) in association with Mancozeb Ingredients (by weight):: A) Compound (II) 3 to 8% B) Mancozeb 65% C) Wetting Agent 0.5 to 5% D) Suspending Agent 1 to 5% E) Carrier 17 to 30.5% Suitable wetting agents (C), suspending agents (D) and carriers (E) are listed in Example 6.

The compositions may be prepared according to the technique described in Example 6.

Table 5 reports examples of composition in wettable powder.

Table 5 Compositions in wettable powder of Compound (II) in association with Mancozeb (ingredients in percent by weight).

Compositions Ingredients 1 2 3 4 A) Compound (Il) 6 3 4 8 B) Mancozeb 65 65 65 65 C) Na-DSS 2 - 5 0.5 C) Na-NS - 2.5 1 1 C) NF-ETO - - - 0.5 D) Na-LS 5 3 2 3 E) Kaolin 18 26.5 - 16 E) Fossil meal - - 23 E) SiO2 4 - - 6 Example 8 Compositions in concentrated suspension of Compound (II) in association with Mancozeb Ingredients (by weight): A) Compound (Il) 1.5 to 4% B) Mancozeb 32.5% C) Surfactant 5 to 20% D) Solvent 43.5 to 61%.

Suitable surfactants and solvents are listed in Example 5.

The compositions are prepared by dissolving compound (II) in the solvent and by admixing the surfactant. To the resulting mixture, Mancozeb is suspended under stirring until a homogenous mixture is obtained.

The following Table 6 reports examples of compositions in concentrated suspension of compound (II) in association with Mancozeb.

Table 6 Compositions in concentrated suspension (ingredients in percent by weight).

Compositions Ingredients 1 2 3 4 A) Compound (Il) 3 1.5 2 4 B) Mancozeb 32.5 32.5 32.5 32.5 C) Ca-DBS 3 1 2 3 C) COH-ETO 3.5 - - 2 C) SO-ETO - 3 10 - D) NF-ETO 3.5 1 1 D) Xylene 54.5 61 53.5 47.5 D) Cyclohexanone - - - 10 The compositions of Examples 5 to 7 have been texted for fungicidal activity against Plasmopara viticola on vines in open-field conditions. All the compositions have shown excellent fungicidal activity in accordance with the high activity shown by compound (II) in laboratory experiments.

Claims (7)

1. N-(2-methyl-5-chlorophenyl)-N-methoxyacetyl-3-amino- 1, 3-oxazolydin-2-one.

2. A fungicide composition comprising, as active ingredient, the compound as claimed in Claim 1 together with a liquid or solid inert carrier.

3. A composition as claimed in Claim 2, which additionally comprises zinc and magnesium ethylene-bis-dithiocarbamate.

4. A composition as claimed in Claim 2 substantially as herein described with reference to any ones of the Examples.

5. A method of combatting fungal infections on useful plants, comprising applying to said plants before or after the onset of infection, an effective amount of the compound as claimed in Claim 1, or a composition as claimed in any one of Claims 2 to 4.

6. A method as claimed in Claim 5, in which the compound is applied to a cultivated area in an amount of from 1 to 100 g/ha.

7. A method as claimed in Claim 5 substantially as herein described with reference to any one of the Examples.