GB2138804A - Fungicidal N-phenylcarbamates - Google Patents

Abstract

The compounds of the formula: <IMAGE> wherein X and Y are each independently a hydrogen atom or a certain specified substituent, with the proviso that X and Y do not simultaneously represent hydrogen; Z is hydrogen, fluorine or a group -OR<4> (R<4> being optionally substituted hydrocarbyl group); R<1> is an optionally substituted phenyl group or a heteroaryl group; R<2> is hydrogen or an organic substituent group, are used as a fungicidal agent against phytopathogenic fungi, particularly those strains resistant to benzimidazole, thiophanate and/or cyclic imide fungicides. Compounds of above formula with the exception of those wherein X, Y and Z simultaneously represent methoxy groups are also claimed per se.

Description

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

Benzimidazole fungicides such as Benomyl (methyl 1-butylcarbamoyl)benzimidazol-2-ylcarbamate), Fubelidazol (2-(2-furyl)benzimidazole), Thiabendazole (2-(4-thiazolyl)-benzimidazole) and Carbendazim (methyl benzimidazol-2-yl-carbamate) and thiphanate fungicides such as Thiophan ate-methyl (1 , 2-bis(3-methoxycarbonyl-2-th iou reido)-benzene), Thiophanate (1 , 2-bis(3-ethoxycar- bonyl-2-thioureido)benzene), 2-(0, S-dimethylphosphorylamino)- 1 -(3'-methoxycarbonyl-2'-thioureido)benzene and 2-(0,0-dimethyl-thiophosphorylamino) I -(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 disease-preventative effect is lowered. Furthermore, the fungi which gain a tolerance to certain benzimidazole and thiophanate fungicides also show considerable tolerance to some other benzimidazole and thiophanate fungicides. Thus, they are apt to develop cross-tolerance. Thus, if any significant decrease in their plant diseasepreventative 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 and thiophanate fungicides in controlling various phytopathogenic fungi. Cyclic imide fungicides such as Procymidone (3-2', 5'-dichlorophenyl)-1 , 2-dimethylcyclopropane- 1 , 2-dicarboximide), Iprodione (3-(3', 5'-dichlorophenyl)-1 -isopropylcarbamoyl-imidazolidine-2,4-dione), Vinchlozoline (3-(3', 5' (dichlorophenyl)-5-methyl-5-vinyloxazolidine-2,4-dione) and ethyl (RS)-3-(3', 5'-d ichlorophenyl)-5methyl-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 and 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-(3-chlorophenyl)carbamate), Chlorpropham (isopropyl N-(3-chlorophenyl)carbamate) and Propham (isopropyl N-phenylcarbamate) exhibit a fungicidal activity against certain organisms tolerant to some of benzimidazole and 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 posses an excellent fungicidal activity against plant pathogenic fungi which have developed resistance to benzimidazole, thiophanate and/or cyclic imide fungicides.

Accordingly, the present invention provides a fungicidal composition which comprises, as an active ingredient, an N-phenylcarbamate of the formula:

wherein X and Y are each independently a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyl group, a lower alkynyl group, a lower haloalkoxy group, a cyano group or a group of the formula:

in which R3is a lower alkyl group with the proviso that X and Y are different when either X or Y is a hydrogen atom; Z is a hydrogen atom, a fluorine atom or a group of the formula: -OR4 in which R4 is a lower alkyl group, a lower alkenyl 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 phenyl group a phenyl group substituted with at least one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy group or a heteroaryl group; R2 is a hydrogen atom, a lower alkyl group, a lower alkenyl group a lower alkynyl group, a lower alkoxycarbonylalkyl group or a group of the formula: -C-R5, -SR5 or -SO2R5 | O in which R5 is a lower alkyl group, a lower cycloalkyl group, a phenyl group, a naphthyl group, a phenyl group substituted with at lease one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy group or an aralkyl group (aralkyl being optionally substituted with at least one halogen atom and/or at least one alkyl group), together with an inert diluent or carrier.It is notable that the fungicidal potency of the compounds of the invention against organisms tolerant to benzimidazole, thiophanate and/or cyclic imide fungicides (hereinafter referred to as "drug-resistant fungi or "drug-resistant strains") is much higher than that against 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 note more than 6 carbon atoms. By the term "heteroaryl" as used herein in connection with organic groups or compounds is meant 5membered heterocycles, condensed 5-membered heterocycles or 6-membered heterocycles such as furyl, thiophenyl, pyrrolyl, pyrasolyl, imidazolyl, 1 ,2,3-triazolyl, 1 ,2,4-triazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyi, benzofuranyl, benzothiophenyl, indolyl, benzimidazolyl, indazolyl, benzoxazolyl, 1, 2-benzisoxazolyl, benzthioazolyl, pyridinyl, pyridazinyl, pyrimidinyl and pyrazinyl.

The N-phenylcarbamates (I) are fungicidally effective against a wide range of plant pathogenic fungi, of which examples are as follows: Podosphaera leucotricha, Venturia inaequalis, Mycosphaerella pomi, Marssonina mali and Scierotinia mali of apple, Phyllactinia kakicola and Gloeosporium kaki of perssimmon, Cladosporiurn 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, Erysiphe graminis f. sp. tritici of wheat, Sphaerotheca fuliginea and Cladosporium cucumerinum of cucumber, Cladosporium fulvum of tomato, Corynespora melongenae of eggpiant, Sphaerotheca humuli, Fusarium oxysporum f. sp. fragariae of strawberry, Botrytis alli of onion, Cercospora apii of cerely, Phaeoisariopsis griseola of kidney bean, Erysiphe cichoracearum of tobacco, Diplocarpon rosae of rose, Elsinoe fawsetti, Penicillium italicum, Penicillium digitatum of orange, Botrytis cinerea of cucumber, eggplant, tomato, strawberry, pimiento, onion, lettuce, grape, orange, cyclamen, rose or hop, Sclerotinia scierotiorum 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-phenylcarbamates (I) are highly effective in controlling drug-resistant strains of the 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 Pyricularia oryzae, Pseudoperonospora cubensis, Plasmopara, viticola, Phytophthora infestans, etc.

Advantageously, the N-phenylcarbamates are low 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 present invention also provides a combination composition comprising as active ingredients the N-phenylcarbamate (I) together with a benzimidazole, thiophanate and/or cyclic imide fungicide, which is fungicidally effective against not only drug-sensitive fungi but also drugresistant 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 N-phenylcarbamate (I) to plant pathogenic fungi. It further provides novel N-phenylcarbamates which are representable by the formula (I) wherein X, Y, Z, A, B, R1 and R2 are each as defined above, with the proviso that X, Y and Z are not each simultaneously a methoxy group. It furthermore provides a process for producing the novel N-phenylcarbamates (I).

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

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

wherein A, B and R' are as defined above.

The reaction is usually carried out in the presence of an inert solvent (e.g. benzene, toluene, tetrahydrofuran, chloroform, ethyl acetate, dimethylformamide). If desired, the reaction may be carried out in the presence of a basic agent (e.g. triethylamine, sodium hydroxide or sodium hydride) so as to obtain the compound (I) in a high yield. The reaction may be carried out at a temperature in the range of from 30 to 120 C instantaneously or within 12 hours.

Procedure (b): The N-phenylcarbamate of formula (I) in which R2 is a hydrogen atom can be prepared by reacting a compound of the formula:

wherein X, Y, Z and A are each as defined above, with a compound of the formula: H-B-R1 wherein B and R are each as defined above.

The reaction is usually carried out in the absence or pesence of an inert solvent (e.g. benzene, toluene, tetrahydrofuan, carbon tetrachloride). If desired, a catalyst (e.g. triethylamine or 1,4 diazabicyclo(2.2.2)octane) may be used. The reaction is normally carried out at a temperature in the range of from 0 to 50 C instantaniously or within 12 hours.

Procedure (c): The compound of formula (i) in which R2 is other than a hydrogen atom can be prepared by reacting a compound of the formula:

wherein X, Y, Z, R2 and A are each as defined above, with a compound of the formula: H-B-R1 wherein B and Fi1 are each as defined above.

The section is usually carried out in the presence of an inert solvent (e.g. benzene, toluene, dimethyl ether, tetrahydrofuran, ethyl acetate). If desired, the reaction may be carried out in the presence of a dehydro-halogenating agent (e.g. pyridine, triethylamine, N,N-diethylaniline, sodium hydroxide) so as to obtain the compound (I) in a high yield. The reaction may be carried out at a temperature in the range of from O to 1 30 C instantaneously or within 12 hours.

Procedure (d): The compound of the formula (I) in which R2 is other than hydrogen can be also prepared by reacting a compound of the formula:

wherein X, Y, Z, R', A and B are each as defined above, with a compound of the formula: W-R2 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, dioxane, chloroform). If desired, a basic agent (e.g. triethylamine, sodium hydroxide or sodium hydride) may be present in the reaction. The reaction may be carried out at a temperature in the range of from 0 to 1 50 C instantaneously or within 1 2 hours.

The starting materials for the production of the compounds of the formula (I) are readily prepared by known methods.

Some typical examples for the preparation of the compounds of formula (I) are illustratively shown below.

Example 1 Preparation of phenyl (N-3,4-diethoxyphenyl)-carbamate according to Procedure (a): 3,4-Diethoxyaniline (1.8 g) and diethylaniline (1.5 g) were dissolved in toluene (20 ml). To the resultant solution was dropwise added phenyl chtoroformate (1.6 g) in 5 minutes under icecooling. After being allowed to stand at room temperature for 1 2 hours, the reaction mixture was poured into ice-water and extracted with toluene. The extract was washed with water, dried over magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography using toluene as the eluent to give phenyl N-(3,4-diethoxyphenyl)car bamate (Compound No. 2) (2.8 g) in a yield of 93.5 %. M.P., 127-128"C.

Example 2 Preparation of isopropyl N-(3, 4-diethoxy-5-methylphenyl)carbamate according to Procedure A mixture of 3,4-diethoxy-5-methylanilie (2.0 g) in toluene (20 ml) was dropwise added to a toluene solution containing 10 g of phosgene at 10 to 20"C. The resulting mixture was gradually heated and, after being refluxed for 30 minutes, cooled to room temperature. The solvent was removed by distillation under reduced pressure to give 3,4-diethoxy-5-methylphenyl isocyanate (2.3 g). The thus obtained crude substance was added to a toluene solution (20 ml) containing phenol (1 g) and triethylamine (1 g). The resultant mixture was allowed to stand at room temperature for 1 2 hours, poured into ice-water and extracted with toluene.The extract was washed with water, dried over magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography using toluene as the eluent to give phenyl N-(3,4-diethoxy-5-methylphenyl)carbamate (Compound No. 19) (3.0 g) in a yield of 92.9 % (calculated from the starting 3,4-diethoxy-5-methylaniline). M.P., 106-107"C.

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

Table 1

Com- Physical pound X Y Z A 8 R1 R2 constant No.

1 -CH3 -CH3 H 0 0 11: H 2 - C2H5 H -0C2H5 4 0 H N12. P8 P 127 3 -oC2H5 H -OC2H5 0 08 Ct H M.P. 126 -oc H OC2H5 H -oc ii M P 1270C 5 -OC2H5 H - C2H5 0 0 1P 8 H.P 118 H 1200C 6 -oC2H5 H -OC2H5 0 O H 14jP 142 H.P. 131 7 OC2H5 H -OC2H5 0 0 H3 H 132.50C 8 - C2H5 H -OC2H5 0 O H3 H N10 P4 103 9 -OC2H5 H -oc2H5 0 0 CH3O H M.P. 122 1230C 10 -oC2H5 H -OC2H5 0 O H3 H M.P. 112 11 -cii2ocu3 H -oc2H5 0 0 O H (Continued)

Com- x z Physical pound X Y Z A B R1 R2 constant No.

12 -C3U7(n) H -OC2H5 0 0 ~cm H 13 -CH2CH=CH2 H -CC 2H5 0 0 ~ < 3 H 14 -C1 -C1 -F O O P U 15 -C1 -C1 OC2H5 0 0 II H.P. 103.5 1050C H.P. 79 16 -CH3 3 or2 5 0 0 ~ < 3 H 810C H 0 0 H 18 17 -OCH3 -C1 - C2H5 0 0 H n0 1.5650 18 - C2H5 -C1 - C2H5 0 0 II H M P 127 19 -0C2H5 3 -oc2H5 0 O H H.P. 106 20 - C2H5 -CH3 3 2H5 0 0 b U 21 - C2H5 -CH3 -OC2H5 0 0 C H 22 - C2H5 CH3 -oC2H5 0 0 Br H 23 C2H5 -CH3 -OC2H5 H3Cs H e 24 C2H5 -CH3 -OC2H5 o o CH3 H (Continued)

Com- Z A B R1 R2 Physical 1 pound X Y constant No.

25 -OC2Hg 'CH3 'OC2Hg s o H 26 - C2H5 -CH3 -0C2H5 | 5 ~Cy H 27 - C2H5 -Cl -OCH2CH=CH2 O O - < H H.P. 103 28 - C2H5 -Cl -OCH2C=-CH O 0 H 29 -CH20CH3 -C1 OC2H5 d H 92 C 30 -CH2ocH3 -C1 -OCH2CH2Cl O O ~ < H 31 -CH20CH3 -C1 -OCH2CN O O ~ H 32 -CH20CH3 -C1 -0CH2 0 0 < > H 33 -CH2OCH3 -C1 -OCH2CH20CH3 O O H 34 -OC2H5 H -OC2H5 0 0 ~Cy -COCH3 35 -OC2H5 H -OC2Hg 0 O -SO2CU3 36 - C2H5 H - C2HS d -C0 < 37 -OC2H5 -CH3 - C2H5 ~ < -CH3 -CU2CU=CU2 38 -0C21i5 -CH3 -OC2H5 0 0 (Continued)

Com- Physical pound X Y Z A B R1 R2 ...,tant No.

39 -OC2Hg -CH3 -OC2Bg 0 O -CH2CaCH 2 5 -OC2H5 CH3 OC2H5 0 0 ~Qy CU3 -CHCOOCH3 41 -0C2H5 -CH3 -OC2H5 0 0 ~ < t3 -SCH3 42 - C2H5 -CH3 - C2H5 0 0 43 -OC2Hg -CH -OC2Hg 0 O -co- 2 5 3 2 5 ~ -CO < ) In the practical usage of the N-phenylcarbamates (I) as a fungicide, they may be applied as such or in a formulation form such as dusts, wettable powders, oil sprays, emulsifiable concentrates, tablets, granules, fine granules, aerosols or flowabies. Such formulation form can be formulated in a conventional manner by mixing at least one of the N-phenylcarbarnates (I) with an appropriate solid or liquid carrier(s) or diluent(s) and, if necessary, an appropriate adjuvant(s) (e.g. sufactants, 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, celluiose 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, cellusolve, 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. dichloro-ethane, carbon tetrachloride), etc.

Examples of the surfactants are alkyl sulfuric ester, alkyl sulfonates, alkylaryl sulfonates, polyethylene glycol ethers, polyhydric alcohol esters, etc. Examples of the adherents and dispersants may include cesein, 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, epoxidyized oil, various surfactants, various fatty acids and their esters, etc.

The foregoing fomulation 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 N-phenylcarbamates (I) are generally applied in such amounts as 2 to 100 g per 10 are.

When only the drug-resistant strains of phytopathogenic fungi are present, the N-phenylcarbamates (I) may be used alone. However, when the drug-sensitive strains are present together with the drug-resistant strains, their alternate use with benzimidazole, thiophanate and/or cyclic imide fungicides or their combined use with benzimidazole, thiophanate 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 formulation forms. In case of the combined use, the weight proportion of the N-phenylcarbamate (I) and the benzimidazole, thiophanate and/or cyclic imide fungicides may be from about 1:0.1 to 1:10.0.

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

Table 2

Compound Structure Name A g > f'N\ Methyl l-(butyl | NHCOOCH3 carbamoyl) benz jrnidazol-2-yl carbamate CONHCgH9 (n) B ,; 2- Na > > (4-Thiazolyl) benz r imidazole H C g --N Methyl benzimidazol N1N\NUCOOCH3 2-ylcarbamate H D g > s--N 2- (2-Furyl) benz irnidazole H E S 1,2-Bis(3-methoxy ll carbonyl-2-thio t NHCNHCOOCH3 ureido)benzene NBNHCOOCH3 3 S F S l,2-Bis(3-ethoxy ii carbonyl-2-tbio VNHCNHCOOC2H5 ureido) benzene çNHiCINHCOOC2H5 S

2-(O,S-Dimethyl- phosphorylamino)-l (3'-methoxycarbonyl2'-thioureido)benzene 2-(O,O-Dimethylthiophosphorylamino)-l (3'-methoxycarbonyl2'-thioureido)benzene N-(3',5'-Dichlorophenyl)-1,2-dimethyl cyclopropane-1 , 2-di- carboximide 3-(3' ,5'-Dichloro- phenyl)-l-isopropylcarbamoylimida zolidin-2,4-dione 3-(3',5'-Dichloro phenyl) -5-methyl-5- vinyloxazolidin-2,4dione Ethyl (RS)-3-(3',5'- dichlorophenyl)-5methyl-2,4-dioxooxazolidine-5carboxylate Besides, the N-phenylcarbamates (I) may be also used in admixture with other fungicides, herbicides, insecticides, miticides, fertilizers, etc.

When the N-phenylcarbamates (I) are used as fungicides, they may be applied in such amounts as 2 to 100 grams per 10 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 emboldiments 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. 2, 88 parts of clay and 10 parts of talc were thoroughly pulverized and mixed together to obtain a dust formulation containing 2% of the active ingredient.

Preparation Example 2 Thirty parts of Compond No. 4, 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 were mixed while being powdered to obtain a wettable powder formulation containing 30 % of the active ingredient.

Preparation Example 3 Twenty parts of Compound No. 19, 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 were mixed while being powdered to obtain a wettable powder formulation containing 30% of the active ingredient.

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

Compound Remarks Swep Commercially available herbicide 0 NHCOCH3 C1 Chlorpropham Commercially available herbicide 0 ss NHCOCHz CU3 C1 < \ CH3 Barban Commercially available herbicide 0 XNHCoCH2C-CCH2Cl C:I):: CEPC Commercially available herbicide 0 -NHCOCH1CHZC1 cZ/ Propham Commercially available herbicide 0 O NHCOCHz 3 \ CH3 Chlorbufam Commercially available herbicide 0 < NHCOCH C1 < \ CH3

Compound Remarks Benomyl Commercially available fungicide CONHC4H9 I I II NHCOOCH3 Thiophanate-methyl Commercially available fungicide S < NHCNHCOOCH3 NHCOOCH3 S Carbendazim Commercially available fungicide H IWNHCOOCH3 WN / > NHCOOCH3 Thiabendazole Commercially available fungicide H Edifenphos Commercially available fungicide ops\8 P-OC2Hg 25 Experiment 1 Protective activity test on powdery mildew of cucumber (Sphaerotheca fuliginea): A fiower pot of 90 ml volume was filed with sandy soil, and seeds of cucumber (var: Sagamihanjiro) were sowed therein. Cultivation was carried out in a greenhouse for 8 days. Onto the resulting seedlings having cotyledons, the test compound formulated inemulsifiable concentrate or wettable powder and diluted with water was sprayed at a rate of 10 ml per pot. Then, the seedlings were 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 was observed. The degree of damage was determined in the following manner, and the results are shown in Table 3.

The leaves examined were measured for a percentage of infected area and classified into the corresponding disease indices, O, 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 was calculated according to the following equation: Disease l; [(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 X100- x 100 (%) (Disease severity in untreated plot) Table 3 Compound Concentration Prevention Prevention No. of active value when value when ingredient inoculated inoculated (ppm) with drug- with drug resistant sensitive strain (%) strain (%) 2 200 94 0 4 200 100 0 7 200 97 0 9 200 100 0 18 200 97 0 19 200 100 0 Swep 200 0 0 Chlorpropham 200 0 0 Barban 200 25 0 CEPC 200 0 0 Propham 200 0 0 Chlorobufam 200 0 0 Benomyl 200 0 100 Thiophanate- 200 0 100 methyl 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 but not on the drug-resistant strain. Other tested compounds structurally similar to the N-phenyl-carbamates (I) do not show any fungicidal acitivity on the drug-sensitive strain and the drug-resistant strain.

Experiment 2 Preventive effect on cercospora leaf spot of sugarbeet (Cercospora beticola): A flower pot of 90 ml volume was filled with sandy soil, and seeds of sugarbeet (var: Detroit dark red) were sowed therein. Cultivation was 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 was sprayed at a rate of 10 ml per pot. Then, the seedlings were inoculated with a spore suspension of the drug-resistant or drug-sensitive strain of Cercospora beticola by spraying. The pot was covered with a polyvinyl chloride sheet to make a condition of high humidity, and cultivation was continued in the greenhouse for 10 days. The degree of damage was determined in the same manner as in Experiment 1, and the results are shown in Table 4.

Table 4 Compound Concentration Prevention Prevention No. of active value when value when ingredient inoculated inoculated (ppm) with drug- with drug resistant sensitive strain (%) strain (%) 2 200 94 0 4 200 100 0 7 200 97 0 18 200 100 0 19 200 100 0 Swep 200 0 0 Chlorpropham 200 0 0 Barban 200 34 0 CEPC 200 0 0 Propham 200 0 0 Chlorobufam 200 0 0 Benomyl 200 0 100 Thiphanate- 200 0 100 methyl 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 compounds 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 Preventative effect on scab of pear (Venturia nashicola): A plastic pot of 90ml volume was filled with sandy soil, and seeds of pear (var: Chojuro) were sowed therein. Cultivation was 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 was sprayed at a rate of 10 ml per pot. Then, the seedlings were inoculated with a spore suspension of the drug-resistant or drug-sensitive strain of Venturia nashicola by spraying. The resulting plants were placed at 20 C under a condition of high humidity for 3 days and then at 204C under irradiation with a fluorescent lamp for 20 days. The degree of damage was determined in the same manner as in Experiment 1, and the results are shown in Table 5.

Table 5 Compound Concentration Prevention Prevention No. of active value when value when ingredient inoculated inoculated (ppm) with drug- wiih-drug- resistant sensitive strain (%) strain (%) 2 200 94 0 4 200 97 0 7 200 94 0 18 200 97 0 19 200 100 0 Benomyl 200 0 100 Thiophanate- 200 0 100 methyl 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 Thioophanate-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 was filled with sandy soil, and seeds of cucumber (var: Sagamihanjiro) were sowed therein. Cultivation was 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 was sprayed at a rate of 10 ml per pot. After air-drying, the seedlings were inoculated with mycelial disks (5 mm in diameter) of the drug-resistant or drug-sensitive strain of Botrytis cinera by putting them on the leaf surfaces. After the plants were infected by incubating under high humidity at 20"C for 3 days, the rates of disease severity were observed.The degree of damage was determined in the same manner as in Experiment 1, and the results are shown in Table 6.

Table 6 Compound Concentration Prevention Prevention No. of active value when value when ingredient inoculated inoculated (ppm) with drug- with drug resistant sensitive strain (%) strain (%) 2 200 100 0 3 200 100 0 4 200 100 0 5 200 97 0 6 200 100 0 7 200 100 0 8 200 94 0 9 200 100 0 10 200 100 0 15 200 88 0 16 200 100 0 17 200 100 0 18 200 100 0 19 200 100 0 27 200 97 0 29 200 100 0 Benomyl 200 0 100 Thiophanate- 200 0 100 methyl 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 was filled with sandy soil, and seeds of cucumber (var: Sagamihanjiro) were sowed therein. Cultivation was 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 were sprayed at a rate of 10 ml per pot. Then, the seedlings were inoculated with a mixed spore suspension of the drug-resistant and drugsensitive strain of Sphaerotheca fuliginea by spraying and further cultivated in the greenhouse.

Ten days thereafter, the infectious state of the plants was observed. The degree of damage was determined in the same manner as in Experiment 1, and the results are shown in Table 7.

Table 7 Compound No. Concentration of Prevention active ingredient value (ppm) (%) 4 100 42 4 20 0 7 100 36 7 20 0 9 100 34 9 20 0 19 100 44 19 20 0 A 100 45 A 20 12 B 500 42 B 100 10 C 100 42 C 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 4+A 20+20 100 4 + B 20 + 20 100 4+E 20+20 100 4+G 20+20 100 7+C 20+20 100 7+D 20+20 100 7+F 20+20 100 7+H 20+20 100 9+A 20+20 100 9+D 20+20 100 9+E 20+20 100 9+G 20+20 100 19+A 20+20 100 19 + B 20 + 20 100 19+E 20+20 100 19+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, thiophahate and/or cyclic imide fungicides show much more excellent preventive effect than their sole use.

invention with benzimidazole, thiophahate 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 was filled with sandy soil, and seeds of tomato (var: Fukuji No 2) were sowed therein. Cultivation was 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 were sprayed at a rate of 10 ml per pot.

Then, the sedlings were 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 was determined in the same manner as in Experiment 1, and the results are shown in Table 8.

Table 8 Compound No. Concentration of Prevention active ingredient value (ppm) (%) 2 100 28 2 20 0 4 100 43 4 20 0 7 100 36 7 20 0 9 100 32 9 20 0 19 100 44 19 20 0 I 100 48 20 22 J 500 46 J 100 18 K 100 42 K 20 15 L 500 42 L 100 12 2+1 20 + 50 100 2+J 20+50 100 4+1 20 + 50 100 4+K 20+50 100 7+1 20+50 100 7 + J 20 + 50 100 9+1 20+50 100 9+L 20+50 100 19+1 20+50 100 19+J 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 and/or cyclic imide fungicides show much more excellent preventive effect than their sole use.

Claims (15)

1. A fungicidal compostion which comprises as an active ingredient a fungicidally effective of an N-phenylcarbamate of the formula:

wherein X and Y are each independently a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyl group, a lower alkynyl group, a lower haloalkoxy group, a cyano group or a group of the formula:

in which R3 is a lower alkyl group with the proviso that X and Y are different when either X or Y is a hydrogen atom; Z is a hydrogen atom, a fluorine atom or a group of the formula -OR4 in which R4 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group or a lower alkyl 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; Rl is a phenyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy group or a heteroaryl group. R2 is a hydrogen atom, a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower alkoxycarbonylalkyl group or a group of the formula:

-SR5 or -SO2R5 in which R5 is a lower alkyl group, a lower cycloalkyl group, a phenyl group, a naphthyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy group or an aralkyl group (aralkyl being optionally substituted with at least one halogen atom and/or at least one alkyl group), together with an inert carrier or diluent.

2. A fungicidal composition as claimed in claim 1, which further comprises as an additional active ingredient(s) a benzimidazole, thiophanate and/or cyclic imide fungicide.

3. A fungicidal composition as claimed in claim 2, wherein the benzi-idazole fungicide is methyl 1 -(butyl-carbamoul)benzimidazole-2-ylcarbamate, 2-(2-furyl)benzimidazole, 2-(4-thiazolyl)benzimidazole or methyl benzimidazol-2-ylcarbamate.

4. A fungicidal composition as claimed in claim 2 wherein the thiophanate fungicide is 1,2- bis(3-methoxy-carbonyl-2-thioureido)bernzene, 1,2-bis(3-ethoxycarbonyl-2-thioureido)benzene, 2 (O,S-dimethylphosphorylamino)- 1 -(3'-methoxycarbonyl-2 '-thioureido)benzene or 2-(O,O-dimethylthio phosphorylamino)-1 (3'-methoxycarbonyl21-thioureido).benzene.

5. A fungicidal composition as claimed in claim 2 wherein the cyclic imide fungicide is 3 (3',4-'dichloro-phenyl)-1 ,2-dimethylcyclopropane-l , 2-dicarboximide, 3-(3', 5'-dichlorophenyl)-1 - isopropylcarbamoulimidazolidine-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 method of controlling plant pathogenic fungi which comprises applying a fungicidally effective amount of at least one N-phenylcarbamate of the formula:

wherein X, Y, Z, A, B, R' and R2 are each as defined in claim 1, to plant pathogenic fungi.

7. A method as claimed in claim 4, wherein the plant pathogenic fungi is a drug-resistant strain.

8. A method of controlling plant pathogenic fungi which comprises applying a fungicidally effective amount of a mixture of an N-phenylcarbamate of the formula:

wherein X, Y, Z, A, B, R1 and R2 are each as defined in claim 1, and a benzimidazole, thiophanate and/or cyclic imide fungicide.

9. A method of controlling plant pathogenic fungi which comprises applying a fungicidally effective amount of a fungicidal composition as claimed in any one of clairms 1 to 5, to plant pathogenic fungi.

10. An N-phenylcarbamate of the formula:

wherein X, Y, Z, R1, R2, A and B are each as defined in claim 1 with the proviso that X, Y and Z are not each simultaneously a methoxy group.

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

wherein X, Y, Z, R1, R2, A and B are each as defined in claim 1 which process comprises reacting a compound of the formula:

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

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

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

wherein X, Y, Z, A, B and Rl are each as defined in claim 1 and R2 is a hydrogen atom which comprises reacting a compound of the formula:

wherein X, V, Z, and A are each as defined above, with a compound of the formula: H-B-R' wherein B and R' are each as defined above.

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

wherein X, Y, Z, A, B and R1 are each as defined in claim 1 and R2 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower alkoxycarbonylalkyl group or a group of the formula:

-SR5 or-SO2R5 in which R5 is a lower alkyl group, a lower cycloalkyl group, a phenyl group, a naphthyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy group or an aralkyl group (aralkyl being optionally substituted with at least one halogen atom and/or at least one alkyl group), which comprises reacting a compound of the formula:

wherein X, Y, Z, A and R2 are each as defined above, with a compound of the formula:: H-B-R1 wherein B and R1 are each as defined above.

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

wherein X, V, Z, A, B and R1 are each as defined in claim 1 and R2 is a lower alkyl group, a lower alkenyl group, a lower alkynyl group, a lower alkoxycarbonylalkyl group or a group of the formula:

-SR5 or -SO2R5 in which R5 is a lower alkyl group, a lower cycloalkyl group, a phenyl group, a napthyl group, a phenyl group substituted with at least one halogen atom, cyano, nitro, trifluoromethyl, lower alkyl or lower alkoxy broup or an aralkyl group (aralkyi being optionally substituted with at least one halogen atom and/or at least one alkyl group), which comprises reacting a compound of the formula:

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

1 5. A process as claimed in any one of claims 11 to 14 substantially as hereinbefore described with reference to any one of the Examples.

1 6. An N-phenylcarbamate as claimed in claim 10 whenever produced by a process as claimed in any one of claims 11 to

1 5.