GB2135667A - Fungicidal N-phenylcarbamates - Google Patents

Abstract

Compounds of the formula <IMAGE> are new and act as a fungicidal agent against phytopathogenic fungi, particularly their strains resistant to benzimidazole thiophanate fungicides and/or cyclic imide fungicides. X and Y are selected from various hydrocarbon, heterocyclic or functional groups; Z is H, F or an (optionally substituted) alkyloxy, alkenyloxy or alkynyloxy group; R<1> and R<2> are selected from a wide variety of hydrocarbon, heterocyclic or functional groups; and A and B represent, independently, an O or S atom.

Description

SPECIFICATION Fungicidal n-phenylcarbamates This invention relates to fungicidal N-phenylcarbamates.

Benzimidazole thiophanate fungicides such as Benomyl (methyl 1 -(butylcarbamoyl)benzimidazol2-ylcarbamate), Fubelidazol (2-(2-furyl)benzimidazole), Thiabendazole (2-(4-thiazolyl)benzimidazole), Carbendazim (methyl benzimidazol-2-ylcarbamate), Thiophanate-methyl (1 ,2-bis(3-methoxycarbonyl- 2-thioureido)benzene), Thiophanate (1 ,2-bis(3-ethoxywarbonyl-2-thioureido)benzene), 2-(O,S dimethylphosphorylamino)-1 -(3'-methoxycarbonyl-2'-thioureido)benzene and 2-(O,O- di methylthiophosphorylamino)-1 -(3'-methoxycarbonyl-2'-thioureido)benzene are known to show an excellent fungicidal activity against various plant pathogenic fungi, and they have been widely used as agricultural fungicides since 1 970.However, their continuous application over a long period of time results in phytopathogenic fungi developing a tolerance to them, whereby their plant diseasepreventative effect is lowered. Furthermore, the fungi which gain a tolerance to certain benzimidazole thiophanate fungicides also show considerable tolerance to some other benzimidazole thiophanate fungicides. Thus, they are apt to develop cross-tolerance. Thus, if any significant decrease in their plant disease-preventative effect in certain fields is observed, their application in such fields has to be discontinued. However, it is often observed that the density of drug-resistant organisms does not decrease even long after the application is discontinued.

Although other types of fungicides have to be used in this case, only a few are as effective as the benzimidazole thiophanate fungicides in controlling various phytopathogenic fungi. Cyclic imide fungicides such as P rocymidone (3-(3',5'-dichlorophenyl)-1 ,2-dimethylcyclopropane- 1,2dicarboximide), Iprodione (3-(3',5'-dichlorophenyl)-1 isopropylcarbamoylimidazolidine-2,4-dione), Vinchlozoline (3-(3',5'-(dichlorophenyl)-5-methyl-5-vinyloxazolidin-2,4-dione), and ethyl (RS)-3-(3',5' dichlorophenyl)-5-methyl-2,4-dioxooxazolidine-5-carboxylate, which are effective against -various plant diseases, particularly those caused by Botrytis cinerea, have the same defects as previously explained with respect to the benzimidazole thiophanate fungicides.

C.R. Acad. Sc. Paris, t. 289, S'erie D, pages 691-693 (1979), discloses that herbicides such as Barban (4-chloro-2-butynyl N-(3-chlorophenyl)carbamate), Chlorobufam (1 -methyl-2-propynyl N-(3chlorophenyl)carbamate), Chlorpropham (isopropyl N-(3-chlorophenyl)carbamate) and Propham (isopropyl N-phenylcarbamate) exhibit a fungicidal activity against certain organisms tolerant to some benzimidazole thiophanate fungicides. However, their fungicidal activity against the drug-resistant fungi is not strong enough, and thus, in practice, they cannot be used as fungicides.

We have now found that certain N-phenylcarbamates possess an excellent fungicidal activity against plant pathogenic fungi which have developed resistance to benzimidazole thiophanate fungicides and/or cycli imide fungicides.

Accordingly, the present invention provides as N-phenylcarbamate of the formula:

wherein X and Y are each independently a halogen atom, a lower alkyl group, a lower alkenyl group, a lower cyano-alkenyl group, a lower alkynyl group, a lower alkoxy group, a cyano group, a lower alkyl group substituted with at least one halogen atom, hydroxy or cyano group, or a group of the formula: -CH2OR3,

which R3 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group or a lower haloalkyl group, R4 and Rs are each independently a lower alkyl group, R6 is a hydrogen atom or a lower alkyl group and n is 2, 3 or 4;Z is a hydrogen atom, a fluorine atom or a group of the formula: -OR7 in which R7 is a lower alkyl group, a loweralkenyl group, a lower alkynyl group or a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy or lower cycloalkyl group; A and B are each independently an oxygen atom or a sulfur atom;R' is a C3-C8 alkenyl group, a C3-C8 alkynyl group, a lower cycloalkyl group, a lower haloalkenyl group, a lower haloalkynyl group, a phenyl group, a lower alkyl group substituted with a least one halogen atom, cyano, lower alkoxy, lower alkenyloxy, lower haloalkoxy, phenoxy, lower aralkyloxy, phenyl or lower cycloalkyl group or a phenyl group substituted with at least one halogen atom, cyano, nitro, lower alkyl or lower alkoxy group; and R2 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower cycloalkyl group, a lower haloalkenyl group, a lower haloalkynyl group, a phenyl group, a naphthyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, lower alkyl, carboxy or lower alkoxy group, a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy, amino, lower alkylamino or phenoxy groups, or a group of the formula:

in which M is an oxygen atom, a sulfur atom or a group of the formula: -NR9- in which R9 is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyl group or a lower alkynyl group, and R8 is a lower alkyl group, a lower alkenyl group a lower alkynyl group, a lower haloalkenyl group, a lower haloalkynyl group, a heteroaryl group, a phenyl group optionally substituted with at least one halogen atom and/or one alkyl group or a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy or lower cycloalkyl group.It is notable that the fungicidal potency of the compounds of the invention against organisms tolerant to benzimidazole thiophanate fungicides and/or cyclic imide fungicides (hereinafter referred to as "drug-resistant fungi" or "drug-resistant strains") is much higher than that against the organisms sensitive to benzimidazole thiophanate fungicides and/or cyclic imide fungicides (hereinafter referred to as "drug-sensitive fungi" or "drug-sensitive strains").

By the term "lower" as used herein in connection with organic groups or compounds is meant that such groups or compounds each contain not more than 6 carbon atoms. Similarly, by the term "heteroaryl" as used herein in connection with organic groups or compounds is meant 5-membered heterocycles, condensed 5-membered heterocycles or 6-membered heterocycles such as furyl, thiophenyl, pyrrolyl, pyrazolyl, imidazolyl, 1 ,2,3-triazolyl, 1 ,2,4-triazolyl, oxazoyl, isoxazolyl, thiazolyl, isothiazolyl, benzofuranyl, benzothiophenyl, indolyl, benzimidazolyl, indazolyl, benzoxazolyl, 1,2benzisoxazolyl, benzthiazoyl, pyridinyl, pyridazinyl, pyrimidinyl and pyrazinyl.

Thus, the present invention provides a fungicidal compound of the formula (I) and a fungicidal composition which comprises as an active ingredient, a fungicidally effective amount of at least one compound of formula (I), together with an inert carrier or diluent. It also provides a combination composition comprising as active ingredients a compound of formula (I) together with a benzimidazole thiophanate fungicide and/or a cyclic imide fungicide, which is fungicidally effective against not only drug-sensitive fungi but also drug-resistant fungi, and hence particularly effective for the prevention of plant diseases.It also provides a method of controlling plant pathogenic fungi including drug-resistant strains and drug-sensitive strains by applying a fungicidally effective amount of the compound of the formula (I) to plant pathogenic fungi, and a process for producing the compound of the formula (I).

An N-phenylcarbamate (I) can be prepared by either one of the following procedures: Procedure (a): The N-phenylcarbamates (I) can be prepared by reacting a compound of the formula:

wherein X, Y, Z, A, B and R1 are each as defined above, with a halide of the formula: R2S-W (Ill) wherein R2 is as defined above and W is a halogen atom.

The reaction is usually carried out in the presence of an inert solvent (e.g. benzene, toluene, xylene, diethyl ether, tetrahydrofuran, dioxane, chloroform, carbon tetrachloride, ethyl acetate, pyridine, dimethylformamide). If desired, the reaction may be carried out in the presence of a dehydrohalogenating agent (e.g. pyridine, triethylamine, diethylaniline, sodium hydroxide, potassium hydroxide) or a phase-transfer catalyst (e.g. tetra-n-butylammonium bromide, benzyl triethylammonium chloride, methyl trioctylammonium chlodie) with an inorganic base (e.g. sodium hydroxide, potassium hydroxide, sodium hydride) so as to obtain the desired compound (I) in a high yield. The reaction may be carried out at a temperature in the range of from 0 to 1 500C, either instantaneously or within 10 hours.

Procedure (b): An N-phenylimidate (I) can also be prepared by reacting a secondary amine of the formula:

wherein X, Y, Z and R2 are each as defined above, with a chloroformate of the formula:

wherein A, B and R1 are each as defined above.

The reaction is usually carried out in the presence of an inert solvent (e.g. benzene, toluene, xylene, diethyl ether, tetrahydrofuran, dioxane, chloroform, carbon tetrachloride, ethyl acetate, pyridine, dimethylformamide). If desired, the reaction may be carried out in the presence of a dehydrohalogenating agent (e.g. pyridine, triethylamine, diethylaniline, sodium hydroxide, potassium hydroxide) or a phasetransfer catalyst (e.g. tetra-n-butylammonium bromide, benzyl triethylammonium chloride, methyl trioctylammonium chlodie) with an inorganic base (e.g. sodium hydroxide, potassium hydroxide) so as to obtain the desired compound (I) in a high yield. The reaction may be carried out at a temperature in the range of from 0 to 1 5O0C either instantaneously or within 1 0 hours.

The N-phenylcarbamates (I) are fungicidally effective against a wide scope of plant pathogenic fungi, of which examples are as follows: Podosphaera leucotricha, Venturia inaegualis, Mycosphaerella pomi, Marssonina mali and Sclerotinia mali of apple, Phyllactinia kakicola and Gloeosporium kaki of persimmon, Cladosporium carpophilum and phomopsis sp. of peach, Cercospora viticola, Uncinula necator, Elsinoe ampelina and Glomerella cingulata of grape, Cercospora beticola of sugarbeet, Cercospora arachidicola and Cercospora personata of peanut, Erysiphe graminis f. sp. hordei, Cercosporella herpotrichoides and Fusarium nivale of barley, Cercosporella herpotrichoides and Fusarium nivale of barley, Erysiphe graminis f. sp. tritici of wheat, Sphaerotheca fuliginea and Cladosporium cucumerinum of cucumber, Cladosporium fulvum of tomato, Corynespora melongenae of eggplant, Sphaerotheca humuli, Fusarium oxysporum f. sp. fragariae of strawberry, Botrytis alli of onion, Cercospora apii of celery, Phaeoisariopsis griseola of kidney bean, Erysiphe cichoracearum of tobacco, Diplocarpon rosae of rose, Elsinoe fawcetti, Penicillium italicum, Penicillium digitatum of orange, Botrytis cinerea of cucumber, eggplant, tomato, strawberry, pimiento, onion, lettuce, grape, orange, cyclamen, rose or hop, Sclerotinia sclerotiorum of cucumber, eggplant, pimiento, lettuce, celery, kidney bean, soybean, azuki bean, potato or sunflower, Sclerotinia cinerea of peach or cherry, Mycosphaerella melonis of cucumber or melon, etc. Namely, the N-phenylimidates (I) are highly effective in controlling the drug-resistant strains of said fungi.

The N-phenylcarbamates (I) are also fungicidally effective against fungi sensitive to the known fungicides as well as fungi against which the known fungicides are ineffective. Examples of such fungi are Pyridularia oryzae, Pseudoperonospora cubensis, Plasmopara, viticola, Phytophthora infestans, etc.

Advantageously, the N-phenylcarbamates (I) low in toxicity and have little detrimental action on mammals and fish. They may be applied to agricultural fields without causing any significant toxicity to important crop plants.

The processes for the preparation of the N-phenylcarbamates (I) are illustratively shown in the following Examples.

EXAMPLE 1 Preparation of isopropyl N-phenylsulfenyl-N-(3-chloro-4-ethoxy-5methoxymethylphenyl)carbamate according to Procedure (a): To a mixture of isopropyl N-(3-chloro-4-ethoxy-5-methoxymethylphenyl)carbamate (3.02 g), dimethylformamide (30 ml) and sodium hydride (0.24 g) was added phenylsulfenyl chloride (1.59 g) with stirring at 250C. The mixture was allowed to stand at 250C for 3 hours, which was then poured into water and extracted with toluene. The extract was washed with dilute hydrochloric acid and water, dried over an hydros magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography using toluene/tetrahydrofuran (9/1) as an eluent to give isopropyl N-phenylsulphenyl-N-(3-chloro-4-ethoxy-5-methoxymethylphenyl)carbamate (3.97 g) in a yield of 97%.

nod3= 1.5591.

EXAMPLE 2 Preparation of isopropyl N-phenylsulfenyl-N-(3,4-diethoxy-5-methylphenyl)carbamate according to Procedure (b): To a solution of N-phenylsulfenyl-N-(3,4-diethoxy-5-methylphenyl)aniline (3.24 g) in 30 ml of toluene were added isopropyl chloroformate (1.59 g) and N,N-diethylanailine (1.94 g) with stirring at 250C. The reaction mixture was wallowed to stand for 3 hours, which was then diluted with water and extracted with toluene. The extract was washed with dilute hydrochloric acid and water, dried over anhydrous magnesium sulfate and concentrated under reduced pressure.The residue was purified by silica gel chromatography using toluene/tetrahydrofuran (9/1) as an eluent to give isopropyl N phenylsulphenyl-N-(3,4-diethoxy-5-methylphenyl)carbamate (3.73 g) in a yield of 96.0%. n22= 1.5596.

According to the above procedures, the N-phenylcarbamate of the formula (I) as shown in Table 1 can be prepared.

TABLE 1

Compound X Y Z A B R1 R2 No.

1 -OH3 - CH3 -H O O CH3 -OH3 2 -Cl -Cl -0C2H5 00 OH3 < I 3 Cl - CH3 --OC,H, O O -C3H7(iso) -C02CH3 4 -OH3 -CH3 -0C2H5 O O -C3H7(iso) 5 H3 -CH3 --OC,H, O O -C3H7(iso) -C02C2H5 6 CH3 -OH3 -002H5 O 0 -CH2CH2F -CCl3 7 H3 -C2H5 ~OC3H7(n) O 0 -CH2C=-CH -CHOl2 8 -CH3 -CH2CH=CH2 -0C2H5 O 0 -CH2C=-CCH2CI -C2H5 9. -Cl OCH3 -0C2H5 OKHC3H2OCH3 3No2 I 10 -Cl -OCH3 -00H2C=-OH O O -CH3 11 Cl OC2H5 OC2H5 O OC3H7(iso) -CH3 12 -Cl -0C2H5 , ~OCH2CH=CH2 00 CH3 -CH(CH2)5CH3 13. Cl OC2H5 -0C2H5 00 CH=CH2 O CH2CH3 -CH(CH2)4CH3 -C-N CH2OH3 14 Cl -0C2H5 -002H5 O 0 -CH2CH2CN -CH2 15 H3 OC2H5 OC2H 5 O -C3H7(iso) -OH3 16 H3 -0C2H5 -0C2H5 O 0 -C3H7(iso) 17 CH3 OC2H5 OC2H5 00 CH3 C02CH3 -CHCH20CH3 18 -OH3 --OC,HS -00H20-=OH O 0 -C3H7(iso) -CO2CH2 < 19 -OH3 OC2H5 OC2H5 O S C3H7(iso) -CH2C0CH2CH3 TABLE 1 (continued)

Compound X y Z A B R1 R2 No.

20 CH=CH2 OC2H5 --OCH,CH,CI O 0 CR3 -CHCH20 -CR2 21 CH20CH3 -Cl OC2Hs O O -C;3H7(iso) -OH3 22 CH2OCH3 -Cl OC2H5 O S | -03H7(iso) 23 CH20CH3 -Cl OC2H5 O O Oj ---C,H,(iso) -0020H3 24 CH2OCH3 -OH3 OC2H5 O O CH3 O I II CHCH20CH3 -COCH2 25 COOCH3 OC2H5 OC2H5 O O -03H7(iso) O II 26 --CN OC2H5 OC2H5 O O --C,H,(iso)C1 27 -CHO OC2H5 OC2H5 O 0 -C3H7(iSO) -CR2N-CR3 28 CONHCH3 OC2H5 OC2H5 O O -03H7(iso) 29 --COCH, OC2H5 OC2H 5 O O -03H7(iso) -CH2 30 -Cl OC2H 5 OC2H5 S O -03H7(iso) -OH 31 CH20CH3 -Cl OC2H5 O O CH3 -CR 3-C --CHCH,OCH, 32 CH2OCH3 -Cl OC2H5 O O -03H7(iso) 33 CH2OCH3 -Cl OC2H 5 O O -03H7(iso) CO2C2Ho5 0 34 -CH3 OC2H5 OC2H5 0 O -CH' II I OCH, --OC,H, --OC,HS - -OH-000H3 CH3 CH3 H OH3 S 0 35 H3 -002H5 OC2H5 , S O C3H7(iso) -002CH20H2Cl 36 Cl OC2H5 OC2H5 S O -03H7(iso) 37 -Cl CH20CH3 --OC,H, S S -03H7(iso) 38 Cl -002H5 jOC2H5 | O O C3H7(iso) -00202H5 39 -OH3 OC2H5 | C2Hs O o -03H7(iso) --CO,CH2CH,CI In the practical usage of the N-phenylcarbamates (I) as fungicides, they may be applied as such or in a preparation form such as dusts, wettable powders, oil sprays, emulsifiable concentrates, tablets, granules, fine granules, aerosols or flowables.Such preparation form can be prepared in a conventional manner by mixing at least one of the N-phenylcarbamates (I) with an appropriate solid or liquid carrier(s) or diluent(s) and, if necessary, an appropriate adjuvant(s) (e.g. surfactants, adherents, dispersants, stabilizers) for improving the dispersibility and other properties of the active ingredient.

Examples of the solid carriers or diluents are botanical materials (e.g. flour, tobacco stalk powder, soybean powder, walnut-shell powder, vegetable powder, saw dust, bran, bark powder, cellulose powder, vegetable extract residue), fibrous materials (e.g. paper, corrugated cardboard, old rags), synthetic plastic powders, clays (e.g. kaolin, bentonite, fuller's earth), talcs, other inorganic materials (e.g. pyrophyllite, sericite, pumice, sulfur powder, active carbon) and chemical fertilizers (e.g.

ammonium sulfate, ammonium phosphate, ammonium nitrate, urea, ammonium chloride).

Examples of the liquid carriers or diluents are water, alcohols (e.g. methanol, ethanol), ketones (e.g. acetone, methylethylketone), ethers (e.g. diethyl ether, dioxane, cellosolve, tetrahydrofuran), aromatic hydrocarbons (e.g. benzene, toluene, xylene, methyl naphthalene), aliphatic hydrocarbons (e.g.

gasoline, kerosene, lamp oil), esters, nitriles, acid amides (e.g. dimethylformamide, dimethylacetamide), halogenated hydrocarbons (e.g. dichloroethane, carbon tetrachloride), etc.

Examples of the surfactants are alkyl sulfuric esters, alkyl sulfonates, alkylaryl sulfonates, polyethylene glycol ethers, polyhydric aicohol esters, etc. Examples of the adherents and dispersants may include casein, gelatin, starch powder, carboxymethyl cellulose, gum arabic, alginic acid, lignin, bentonite, molasses, polyvinyl alcohol, pine oil and agar. As the stabilizers, there may be used PAP (isopropyl acid phosphate mixture), tricresyl phosphate (TCP), tolu oil, epoxydized oil, various surfactants, various fatty acids and their esters, etc.

The foregoing preparations generally contain at least one of the N-phenylcarbamates (I) in a concentration of about 1 to 95% by weight, preferably of 2.0 to 80% by weight. By using the preparations, the phenylcarbamates (I) are generally applied in such amounts as 2 to 100 g per 10 ares.

When only the drug-resistant strains of phytopathogenic fungi are present, the N-phenylimidates (I) may be used alone. However, when the drug-sensitive strains are present together with the drugresistant strains, their alternate use with benzimidazole thiophanate fungicides and/or cyclic imide fungicides or their combined use with benzimidazole thiophanate fungicides and/or cyclic imide fungicides is favorable. In such alternate or combined use, each active ingredient may be employed as such or in conventional agricultural preparation forms. In case of the combined use, the weight proportion of the N-phenylcarbamates (I) and the benzimidazole thiophanate fungicide and/or the cyclic imide fungicide may be from about 1:0.1 to 1 :10.0.

Typical examples of the benzimidazole thiophanate fungicides and the cyclic imide fungicides are shown in Table 2.

TABLE 2

Compound Structure Name A X N\ > NHCOOCH3 Methyl 1 -(butylcarbamoyl)benzimidazol-2-yl HCOOCH3 carbamate CONHC4H9(n) B 4 < \ > C 2-(4-Thiazolyl)benzimidazole H C $t yNHCOOCH3 Methyl benzimidazol-2-ylcarbamate H D mN 2-(2-Furyl)benzimidazole H E S 1 ,2-Bis(3-methoxycarbonyl-2 II WHCNHCOOCH3 thioureido)benzene ID$INNHCCNHCOOCH3 1/ S F S 1 ,2-Bis(3-ethoxycarbonyl-2-thioureido)benzene II ( H5 /1NHCNHCOOC2Hg S G S 2-(O,S-Dimethylphosphorylamino)-l -(3' II methoxycarbonyl-2'-thioureido)benzene !%INNHCNflCOOCH3 NHP -S-CH il \ O OCH3 H S 2-(0,0-Dimethylthiophosphorylamino)-1 -(3' II methoxycarbonyl-2'-thioureido)benzene /NHCNHCOOCH3 i;;ĬKNNHCpNHCOOCH3 1\OCH3 S OCH3 I CH3 N-(3' ,5'-Dichlorophenyl)-1 2 Cl > ss %H3 2-dicarboximide 0 TABLE 2 (continued)

3-(3',5'-Dichlorophenyl)-1 -isopropyl carbamoylimidazolidin-2,4-dione 3-(3' ,5'-Dichlorophenyl)-5-methyl-5-vinyl oxazolidin-2,4-dione Ethyl (RS)-3-(3',5'-dichlorophenyl)-5-methyl 2 ,4-dioxooxazolidi ne-5-carboxyíate Besides, the N-phenylcarbamates (I) may be also used in admixture with other fungicides, herbicides, insecticides, miticides, fertilizers, etc.

When the phenylcarbamates (I) are used as fungicides, they may be applied in such amounts as 2 to 100 grams per 1 0 ares. However, this amount may vary depending upon preparation forms, application times, application methods application sites, diseases, crops and so on, and therefore, they are not limited to said particular amounts.

Some practical embodiments of the fungicidal composition according to the invention are illustratively shown in the following Examples wherein % and part(s) are by weight.

FORMULATION EXAMPLE 1 Two parts of Compound No. 15,88 parts of clay and 10 parts of talc are thoroughly pulverized and mixed together to obtain a dust preparation containing 2% of the active ingredient.

FORMULATION EXAMPLE 2 Thirty parts of Compound No. 16,45 parts of diatomaceous earth, 20 parts of white carbon, 3 parts of sodium laurylsulfate as a wetting agent and 2 parts of calcium ligninsulfonate as a dispersing agent are mixed while being powdered to obtain a wettable powder preparation containing 30% of the active ingredient.

FORMULATION EXAMPLE 3 One part of Compound No. 32, 1 part of Compound 1,88 parts of clay and 10 parts of talc are thoroughly pulverized and mixed together to obtain a dust preparation containing 2% of the active ingredient.

FORMULATION EXAMPLE 4 Twenty parts of Compound No. 23, 10 parts of Compound J. 45 parts of diatomaceous earth, 20 parts of white carbon, 3 parts of sodium laurylsulfate as a wetting agent and 2 parts of calcium ligninsulfonate as a dispersing agent are mixed while being powdered to obtain a wettable powder preparation containing 30% of the active ingredient.

Typical test data indicating the excellent fungicidal activity of the phenylcarbamates (I) are shown below. The compounds used for comparison are as follows:

Compound Remarks Swep 0 Commercially available Cl9NHCOCH3 herbicide C1 Chlorpropham o II /CH3 Commercially available 'NHCOCH herbicide > :t , \CH herbicide Cl. 3 Barban o 0 It Commercially available ci\NHCOCH2C=CCH2C1 herbicide CEpC 0 Commercially available NHCoCH2CB2C1 herbicide clT herbicide Propham o Commercially available O NHCOCH 3 herbicide 3 Chlorbufam o Commercially available ss NHCOCH herbicide > \CH3 Cl 3 Benomvl CONHC4H9 Commercially available fungicide N /WSHCooCH3 Thiohanate-methv 1 S 11 NHCNHCOOCH3 Commercially available I( available uNHiCNHCOOCH3 fungicide S

Compound Remarks Carbendaz jut H Commercially available fungicide ,"'I/NHCOOCH3 Thiabendazole H Commercially available fungicide S Edifenphos so o Commercially available - \II fungicide 5/PUC2Hs eS/ Experiment 1 Protective activity test on powdery mildew of cucumber (Sphaerotheca fuliginea):-- A flower pot of 90 ml volume is filled with sandy soil, and seeds of cucumber (var: Sagami-hanjiro) are sowed therein. Cultivation is carried out in a greenhouse for 8 days.Onto the resulting seedlings having cotyledons, the test compound formulated in emulsifiable concentrate or wettable powder and diluted with water is sprayed at a rate of 10 ml per pot. Then, the seedlings are inoculated with a spore suspension of the drug-resistant or drug-sensitive strain of Sphaerotheca fuliginea by spraying and further cultivated in the greenhouse. Ten days thereafter, the infectious state of the plants is observed.

The degree of damage is determined in the following manner.

The leaves examined are measured for a percentage of infected area and classified into the corresponding disease indices, 0, 0.5, 1, 2, 4: Disease index Percentage of infected area O No infection 0.5 Infected area of less than 5% 1 Infected area of less than 20% 2 Infected area of less than 50% 4 Infected area of not less than 50% The disease severity is calculated according to the following equation: Disease Disease index) x (Number of leaves) severity = x 100 (%) 4 x (Total number of leaves examined) The prevention value was calculated according to the following equation: Prevention (Disease severity in treated plot) value =100- x 100 (%) (Disease severity in untreated plot) The results are shown in Table 3.

TABLE 3

Concentration Prevention value Prevention value of active when inoculated when inoculated Compound ingredient with drug-resistant with drug-sensitive No. (ppm) strain (%) strain (%) 4 200 100 0 15 200 100 0 16 200 100 0 17 200 100 0 23 200 100 0 32 200 100 0 39 200 100 0 Swep 200 0 0 Chlorpropham 200 0 0 Barban 200 25 0 CEPC 200 0 0 Propham 200 0 0 Chlorbufam 200 0 0 Benomyl 200 0 100 Thiophanatemethyl 200 0 100 Carbendazim 200 0 100 As understood from the results shown in Table 3, the N-phenylcarbamates (I) of the invention show an excellent preventive effect on the drug-resistant strain but do not show any preventive effect on the tested drug-sensitive strain. To the contrary, commercially available known fungicides such as Benomyl, Thiophanate-methyl and Carbendazim show a notable controlling effect on the drug-sensitive strain bot not on the drug-resistant strain. Other tested compounds structurally similar to the Nphenylcarbamates (I) do not show any fungicidal activity on the drug-sensitive strain and the drugresistant strain.

Experiment 2 Preventive effect on cercospora leaf spot of sugarbeet (Cercospora beticola):- A flower pot of 90 ml volume is filled with sandy soil, and seeds of sugarbeet (var: Detroit dark red) are sowed therein. Cultivation is carried out in a greenhouse for 20 days. Onto the resulting seedlings, the test compound formulated in emulsifiable concentrate or wettable powder and diluted with water is sprayed at a rate of 10 ml per pot. Then, the seedlings are inoculated with a spore suspension of the drug-resistant or drug-sensitive strain of Cercospora beticola by spraying. The pot is covered with a polyvinyl chloride sheet to make a condition of high humidity, and cultivation is continued in the greenhouse for 10 days. The degree of damage is determined in the same manner as in Experiment 1.

The results are shown in Table 4.

TABLE 4

Concentration Prevention value Prevention value of active when inoculated when inoculated Compound ingredient with drug-resistant with drug-sensitive No. (ppm) strain (%) strain (%) 15 200 100 0 16 200 100 0 17 200 100 0 32 200 100 0 39 200 100 0 Swep 200 0 0 Chlorpropham 200 0 0 Barban 200 34 0 CEPC 200 0 0 Propham 200 0 0 Chlorbufam 200 0 0 Benomyl 200 0 100 Thiophanate-methyl 200 0 100 Carbendazim 200 0 100 As understood from the results shown in Table 4, the N-phenylcarbamates (I) of the invention show an excellent preventive effect on the drug-resistant strain but do not show any preventive effect on the tested drug-sensitive strain. To the contrary, commercially available known fungicides such as Benomyl and Thiophanate-methyl show a notable controlling effect on the drug-sensitive strain but not on the drug-resistant strain. Other tested cdmpounds structurally similar to the N-phenylcarbamates (I) do not show any fungicidal activity on the drug-sensitive strain and the drug-resistant strain.

Experiment 3 Preventive effect on scab of pear (Venturia nashicola):- A plastic pot of 90 ml volume is filled with sandy soil, and seeds of pear (var: Chojuro) were sowed therein. Cultivation is carried out in a greenhouse for 20 days. Onto the resulting seedlings, the test compound formulated in emulsifiable concentrate or wettable powder and diluted with water is sprayed at a rate of 10 ml per pot. Then, the seedlings are inoculated with a spore suspension of the drugresistant or drug-sensitive strain of Venturia nashicola by spraying. The resulting plants are placed at 200C under a condition of high humidity for 3 days and then at 200C under irradiation with a fluorescent lamp for 20 days. The degree of damage is determined in the same manner as in Experiment 1.

The results are shown in Table 5.

TABLE 5

Concentration Prevention value Prevention value of active when inoculated when inoculated Compound ingredient with drug-resistant with drug-sensitive No. (ppm) strain (96) strain (%) 4 200 94 0 17 200 100 O 23 200 100 0 32 200 100 0 39 200 100 0 Benomyl 200 0 100 Thiophanate-methyl 200 0 100 As understood from the results shown in Table 5, the N-phenylcarbamates (I) of the invention show an excellent preventive effect on the drug-resistant strain but do not show any preventive effect on the tested drug-sensitive strain. To the contrary, commercially available known fungicides such as Benomyl and Thiophanate-methyl show a notable controlling effect on the drug-sensitive strain but not on the drug-resistant strain.

Experiment 4 Preventive effect on gray mold of cucumber (Botrytis cinerea): Plastic pots of 90 ml volume is filled with sandy soil, and seeds of cucumber (var: Sagami-hanjiro) were sowed therein. Cultivation is carried out in a greenhouse for 8 days to obtain cucumber seedlings expanding cotyledons. Onto the resulting seedlings, the test compound formulated in emulsifiable concentrate or wettable powder and diluted with water is sprayed at a rate of 10 ml per pot. After airdrying, the seedlings are inoculated with mycelial disks (5 mm in diameter) of the drug-resistant or drug-sensitive strain of Botrytis cinerea by putting them on the leaf surfaces. After the plants are infected by incubating under high humidity at 200C for 3 days, the rates of disease severity are observed.The degree of damage is determined in the same manner as in Experiment 1.

The results are shown in Table 6.

TABLE 6

Concentration Prevention value Prevention value of active when inoculated when inoculated Compound ingredient with drug-resistant with drug-sensitive No. (ppm) strain (%) strain (%) 4 200 100 0 5 200 100 0 15 200 100 0 16 200 100 0 17 200 100 0 23 200 100 0 32 200 100 0 39 200 100 0 Benomyl 200 0 100 Thiophanate-methyl 200 0 100 As understood from the results shown in Table 6, the N-phenylcarbamates (I) of the invention show an excellent preventive effect on the drug-resistant strain but do not show any preventive effect on the tested drug-sensitive strain.To the contrary, commercially available known fungicides such as Benomyl, Thiophanate-methyl and Carbendazim show a notable controlling effect on the drug-sensitive strain but not on the drug-resistant strain.

Experiment 5 Preventive effect on powdery mildew of cucumber (Sphaerotheca fuliginea):-- A plastic pot of 90 ml volume is filled with sandy soil, and seeds of cucumber (var: Sagamihanjiro) are sowed therein. Cultivation is carried out in a greenhouse for 8 days. Onto the resulting seedlings having cotyledons, the test compound(s) formulated in emulsifiable concentrate or wettable powder and diluted with water are sprayed at a rate of 10 ml per pot. Then, the seedlings are inoculated with a mixed spore suspension of the drug-resistant and drug-sensitive strain of Sphaerotheca fuliginea by spraying and further cultivated in the greenhouse. Ten days thereafter, the infectious state of the plants is observed. The degree of damage is determined in the same manner as in Experiment 1.

The results are shown in Table 7.

TABLE 7

Concentration of Prevention Compound No. active ingredient (ppm) value (%) 15 100 36 15 20 0 16 100 41 16 20 0 32 100 34 32 20 0 39 100 43 39 20 0 A 100 45 A 20 12 B 500 42 B 100 10 O 100 42 O 20 8 D 500 36 D 100 0 E 100 44 E 20 10 F 100 43 F 20 8 G 100 42 G 20 8 H 100 40 H 20 5 15+A 20 + 20 100 15+B 20+20 100 15+E 20+20 100 15+G 20+20 100 16+0 to + 20 100 16+D 20+20 100 16+F 20 + 20 100 16+H 20+20 100 32+A 20+20 100 32 + D 20 + 20 100 32 + E 20 + 20 100 32+G 20+20 100 39+A 20 + 20 100 39+B 20 + 20 100 39 + E 20 + 20 100 39+G 20+20 100 As understood from the results shown in Table 7, the combined use of the N-phenylcarbamates (I) of the invention with benzimidazole thiophanate fungicides and/or cyclic imide fungicides show much more excellent preventive effect than their sole use.

Experiment 6 Preventive effect on gray mold of tomato (Botrytis cinerea): A plastic pot of 90 ml volume is filled with sandy soil, and seeds of tomato (var: Fukuji No. 2) are sowed therein. Cultivation is carried out in a greenhouse for 4 weeks. Onto the resulting seedlings at the 4-leaf stage, the test compound(s) formulated in emulsifiable concentrate or wettable powder and diluted with water are sprayed at a rate of 10 ml per pot. Then, the seedlings are inoculated with a mixed spore suspension of the drug-resistant and drug-sensitive strain of Botrytis cinerea by spraying and placed at 20 C in a room of high humidity for 5 days. The degree of damage is determined in the same manner as in Experiment 1.

The results are shown in Table 8.

TABLE

Concentration of Prevention Compound No. active ingredient (ppm) value (%) 4 100 33 4 20 0 15 100 42 15. 20 0 16 100 27 16 20 0 23 100 25 23 20 0 39 100 43 39 20 0 100 48 l 20 22 J 500 46 J 100 18 K 100 42 K 20 15 L 500 42 L 100 12 4+1 20+50 100 4+K 20+50 100 15+1 20+50 100 15+J 20 + 50 100 15+K 20 + 50 100 15+L 20+50 100 16+1 20+50 100 16+L 20+50 100 23+1 20+50 100 23+K 20+50 100 39+1 20 + 50 100 39+J 20+50 100 39 + K 20 + 50 100 39 + L 20 + 50 100 As understood from the results shown in Table 8, the combined use of the N-phenylcarbamates (I) of the invention with benzimidazole thiophanate fungicides and/or cyclic imide fungicides show much more excellent preventive effect than their sole use.

Claims (12)

1. An N-phenylcarbamate of the formula:

wherein X and Y are each independently a halogen atom, a lower alkyl group, a lower alkenyl group, a lower cyanoalkenyl group, a lower alkynyl group, a lower alkoxy group, a cyano group, a lower alkyl group substituted with at least one halogen atom, hydroxy or cyano group, or a group of the formula: -CH2OR3,

in which R3 is a lower alkyl group a lower alkenyl group, a lower alkynyl group or a lower haloalkyl group, R4 and R5 are each independently a lower alkyl group, R6 is a hydrogen atom or a lower alkyl group an n is 2, 3 or 4;Z is a hydrogen atom, a fluorine atom or a group of the formula: -OR7 in which R7 is a lower alkyl group, a lower alkenyl group, a lower aikenyl group, a lower alkynyl group or a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy or lower cycloalkyl group; A and B are each independently an oxygen atom or a sulfur atom;R1 is a CXC8 alkyl group, a C3C8 alkenyl group, a 03-C8 alkynyl group, a lower cycloalkyl group, a lower haloalkenyl group, a lower haloalkynyl group, a phenyl group, a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy, lower alkenyloxy, lower haloalkoxy, phenoxy, lower aralkyloxy, phenyl or lower cycloalkyl group or a phenyl group substituted with at least one halogen atom, cyano, nitro, lower alkyl or lower alkoxy group; and R2 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower cycloalkyl group, a lower haloalkenyl group, a lower haloalkynyl group, a phenyl group, a naphthyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, lower alkyl, carboxy or lower alkoxy group, a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy, amino, lower alkylamino or phenoxy group, or a group of the formula:

in which M is an oxygen atom, a sulfur atom or a group of the formula: -NR9- in which R9 is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyl group or a lower alkynyl group, and R8 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower haloalkenyl group, a lower haloalkynyl group, a heteroaryl group, a phenyl group optionally substituted with at least one halogen atom and/or one alkyl group or a lower alkyl group substituted with at least one halogen atom, cyano, lower alkoxy or lower cycloalkyl group.

2. A fungicidal composition which comprises as an active ingredient a fungicidally effective amount of an N-phenylcarbamate of the formula:

wherein, X, Y, Z, A, B, R1 and R2 are each as defined in claim 1 together with an inert carrier or diluent.

3. A fungicidal composition as claimed in claim 2 which further comprises as an additional active ingredient(s) a benzimidazole thiophanate fungicide and/or a cyclic imide fungicide.

4. A fungicidal composition as claimed in claim 3 wherein the benzimidazole thiophanate fungicide is methyl (butylcarbamoyl)benzimidazol-2-ylcarbamate, 2-(2-furyl) benzimidazole, 2-(4thiazolyl)benzimidazole, methyl benzimidazol-2-ylcarbamate, 1 ,2-bis(3-methoxycarbonyl-2-thioureido) benzene, 1 ,2-bis(3-ethoxycarbonyl-2-thioureido)-benzene, 2-(O,S-dimethylphosphorylamino)-1 -(3'- methoxycarbonyl-2'-thioureido)benzene or 2-(O,O-dimethylthiophosphorylamino)- 1-(3'- methoxycarbonyl-2'-thioureido)benzene.

5. A fungicidal composition as claimed in claim 3 wherein the cyclic imide fungicide is 3-(3',5' dichlorophenyi)-l ,2-dimethylcyclopropane- 1 ,2-dicarboximide, 3-(3',5'-dichlorophenyl)- 1 - isopropylcarbamoylimidazolidine-2,4-dione, 3-(3',5'-dichlorophenyl)-5-methyl-5-vinyloxazolidine-2,4- dione or ethyl (RS)-3-(3',5'--dichlorophenyl)-5-methyl-2,4-dioxooxazolidine-5-carboxylate.

6. A fungicidal composition as claimed in any one of claims 2 to 5 which contains from 1 to 95% by weight of the said N-phenylcarbamate.

7. A method of controlling plant pathogenic fungi which comprises applying a fungicidally effective amount of at least one N-phenylcarbamates of the formula:

wherein X, Y, Z, A, B, R1 and R2 are each as defined in claim 1, or a composition as claimed in any one of claims 2 to 6, to plant pathogenic fungi.

8. A method as claimed in claim 7, wherein the plant pathogenic fungi is a drug-resistant strain.

9. A process for producing an N-phenylcarbamate of the formula:

wherein X, Y, Z, A, B, R' and R2 are each as defined in claim 1 which process comprises (a) reacting a compound of the formula:

wherein X, Y, Z, A, B and R1 are each as defined above, with a halide of the formula: R2S-W wherein R2 is as defined in claim 1 and W is a halogen atom; or (b) reacting a secondary amine of the formula:

wherein X, Y, Z and R2 are each as defined in claim 1 with a chloroformate of the formula:

wherein A, B and R' are each as defined in claim 1.

10. A process as claimed in claim 9 substantially as hereinbefore described in Example 1 or Example 2.

11. A compound as claimed in claim 1 whenever produced by a process as claimed in claim 9.

12. A composition as claimed in claim 2 substantially as hereinbefore described with reference to any one of Formulation Examples 1 to 4.

1 3. A method as claimed in claim 7 substantially as hereinbefore described with reference to any one of Experiments 1 to 6.