2-[[5-(TRIFLUOROMETHYL)-1,2,4-OXADIAZOL-3-YL]ARYLOXY](THIO)ACETAMIDES FOR COMBATING PHYTOPATHOGENIC FUNGI

Abstract

The present invention relates the compounds of the formula I

##STR00001##

and their N-oxides and agriculturally acceptable salts thereof, and their use for combating phytopathogenic harmful fungi, wherein the variables are defined as given in the description and claims. Further the present invention relates to novel mixtures comprising at least one such compound of the formula I and at least one further pesticidally active substance selected from the group consisting of herbicides, safeners, fungicides, insecticides, and plant growth regulators; and to agrochemical compositions comprising at least one such compound of the formula I and to agrochemical compositions further comprising seeds.

Claims

1.-15. (canceled)

16. A compound of the formula I ##STR00024## wherein: A is phenyl or a 5- or 6-membered aromatic heterocycle; wherein the ring member atoms of the aromatic heterocycle include besides carbon atoms 1, 2, 3 or 4 heteroatoms selected from the group consisting of N, O and S as ring member atoms; and wherein the phenyl ring or the 5- or 6-membered aromatic heterocycle are unsubstituted or substituted with 1, 2, 3 or 4 identical or different groups R.sup.A; wherein R.sup.A is halogen, cyano, diC.sub.1-C.sub.6-alkylamino, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy, C.sub.1-C.sub.6-alkylthio, C.sub.1-C.sub.6-alkylsulfinyl, C.sub.1-C.sub.6-alkylsulfonyl, C.sub.2-C.sub.6-alkenyl, C.sub.2-C.sub.6-alkynyl, C.sub.3-C.sub.11-cycloalkyl or C.sub.3-C.sub.11-cycloalkoxy; and wherein any of the aliphatic or cyclic moieties are unsubstituted or substituted with 1, 2, 3 or 4 identical or different groups R.sup.a; wherein R.sup.a is halogen, cyano, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-haloalkyl, C.sub.1-C.sub.6-alkoxy, or C.sub.1-C.sub.6-haloalkoxy; Y is O or S; R.sup.3, R.sup.4 independently of each other are selected from the group consisting of hydrogen, halogen, cyano, C.sub.1-C.sub.4-alkyl, C.sub.1-C.sub.4-alkenyl, C.sub.1-C.sub.4-alkynyl, C.sub.1-C.sub.4-alkoxy C.sub.1-C.sub.4-haloalkyl and C.sub.1-C.sub.4-haloalkoxy; or R.sup.3 and R.sup.4 together with the carbon atom to which they are bound form a saturated 3- to 7-membered carbocycle or a saturated 3- to 6-membered heterocycle; wherein the saturated heterocycle includes beside carbon atoms 1, 2 or 3 heteroatoms independently selected from the group consisting of N, O and S as ring member atoms; and wherein said N ring member atom is substituted with the group R.sup.N; wherein R.sup.N is hydrogen, C.sub.1-C.sub.6-alkyl or halogen; and wherein said S ring member atom is unsubstituted or substituted with 1 or 2 oxo radicals; and wherein one or two of the ring member CH.sub.2 groups of said saturated carbocycle or of said saturated heterocycle may be replaced by one or two groups independently selected from the group consisting of C(O) and C(S); and wherein the carbon ring member atoms of the saturated carbocycle or of the saturated heterocycle are unsubstituted or substituted with a total number of 1, 2, 3, 4 or up to the maximum possible number of identical or different radicals selected from the group consisting of halogen, cyano, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy and C.sub.3-C.sub.11-cycloalkyl; X is O or S; W is NR.sup.2, O or S; R.sup.2 is selected from the group consisting of hydrogen, CH(O), C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl, C.sub.2-C.sub.6-alkynyl, C.sub.1-C.sub.6-alkoxy, C.sub.3-C.sub.11-cycloalkyl, C.sub.3-C.sub.8-cycloalkenyl, C.sub.3-C.sub.11-cycloalkyl-C.sub.1-C.sub.4-alkyl, phenyl-C.sub.1-C.sub.4-alkyl, phenyl, pyridinyl, C(O)(C.sub.1-C.sub.6-alkyl), C(O)(C.sub.3-C.sub.11-cycloalkyl), C(O)(C.sub.1-C.sub.6-alkoxy) and N(R.sup.2a).sub.2; wherein R.sup.2a is independently selected from the group consisting of hydrogen, OH, C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl, C.sub.2-C.sub.6-alkynyl, C.sub.3-C.sub.11-cycloalkyl, C.sub.3-C.sub.8-cycloalkenyl, C.sub.1-C.sub.6-alkoxy, C.sub.1-C.sub.4-alkoxy-C.sub.1-C.sub.4-alkyl and C.sub.1-C.sub.6-alkylthio; and wherein any of the aliphatic or cyclic groups in R.sup.2 are unsubstituted or substituted with 1, 2, 3 or up to the maximum possible number of identical or different radicals selected from the group consisting of halogen, hydroxy, oxo, cyano, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy and C.sub.3-C.sub.11-cycloalkyl; R.sup.1 is hydrogen, CH(O), C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy, C.sub.3-C.sub.11-cycloalkyl, C.sub.3-C.sub.8-cycloalkenyl, C.sub.2-C.sub.6-alkenyl, C.sub.2-C.sub.6-alkynyl, C.sub.1-C.sub.6-alkoxyimino-C.sub.1-C.sub.4-alkyl, C.sub.2-C.sub.6-alkenyloxyimino-C.sub.1-C.sub.4-alkyl, C.sub.2-C.sub.6-alkynyloxyimino-C.sub.1-C.sub.4-alkyl, phenyl-C.sub.1-C.sub.4-alkyl, phenyl-C.sub.1-C.sub.4-alkenyl, phenyl-C.sub.1-C.sub.4-alkynyl, heteroaryl-C.sub.1-C.sub.4-alkyl, phenyl, naphthyl or a 3- to 10-membered saturated, partially unsaturated or aromatic mono- or bicyclic heterocycle, wherein the ring member atoms of said mono- or bicyclic heterocycle include besides carbon atoms further 1, 2, 3 or 4 heteroatoms selected from the group consisting of N, O and S as ring member atoms; and wherein the heteroaryl group in the group heteroaryl-C.sub.1-C.sub.4-alkyl is a 5- or 6-membered aromatic heterocycle, wherein the ring member atoms of the heterocyclic ring include besides carbon atoms 1, 2, 3 or 4 heteroatoms selected from N, O and S as ring member atoms; and wherein any of the above-mentioned aliphatic or cyclic groups are unsubstituted or substituted with 1, 2, 3 or up to the maximum possible number of identical or different groups R.sup.1a; or if W is NR.sup.2, R.sup.1 and R.sup.2, together with the nitrogen atom to which R.sup.2 is attached, may form a saturated or partially unsaturated mono- or bicyclic 3- to 10-membered heterocycle, wherein the heterocycle includes beside one nitrogen atom and one or more carbon atoms no further heteroatoms or 1, 2 or 3 further heteroatoms independently selected from the group consisting of N, O and S as ring member atoms; and wherein the heterocycle is unsubstituted or substituted with 1, 2, 3, 4 or up to the maximum possible number of identical or different groups R.sup.1a; or if W is NR.sup.2 and R.sup.2 is N(R.sup.2a).sub.2, R.sup.1 and one of the two groups R.sup.2a, together with the nitrogen atom to which said R.sup.2a is attached, and together with the nitrogen atom to which the group R.sup.1 attached, may form a saturated or partially unsaturated mono- or bicyclic 3- to 10-membered heterocycle, wherein the heterocycle includes beside two nitrogen atoms and one or more carbon atoms no further heteroatoms or 1, 2 or 3 further heteroatoms independently selected from the group consisting of N, O and S as ring member atoms; and wherein the heterocycle is unsubstituted or substituted with 1, 2, 3, 4 or up to the maximum possible number of identical or different groups R.sup.1a; R.sup.1a is halogen, oxo, cyano, NO.sub.2, OH, SH, NH.sub.2, C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl, C.sub.2-C.sub.6-alkynyl, C.sub.1-C.sub.6-haloalkyl, C.sub.1-C.sub.6-alkoxy, C.sub.1-C.sub.6-haloalkoxy, C.sub.1-C.sub.6-alkylthio, C.sub.1-C.sub.6-haloalkylthio, C.sub.3-C.sub.11-cycloalkyl, NHSO.sub.2C.sub.1-C.sub.4-alkyl, (CO)C.sub.1-C.sub.4-alkyl, C(O)C.sub.1-C.sub.4-alkoxy, C.sub.1-C.sub.6-alkylsulfonyl, hydroxyC.sub.1-C.sub.4-alkyl, C(O)NH.sub.2, C(O)NH(C.sub.1-C.sub.4-alkyl), C.sub.1-C.sub.4-alkylthio-C.sub.1-C.sub.4-alkyl, aminoC.sub.1-C.sub.4-alkyl, C.sub.1-C.sub.4-alkylamino-C.sub.1-C.sub.4-alkyl, diC.sub.1-C.sub.4-alkylamino-C.sub.1-C.sub.4-alkyl, aminocarbonyl-C.sub.1-C.sub.4-alkyl or C.sub.1-C.sub.4-alkoxy-C.sub.1-C.sub.4-alkyl; or the N-oxides, or the agriculturally acceptable salts thereof.

17. The compound of claim 16, wherein A is a phenyl ring.

18. The compound of claim 16, wherein A is a thiophene ring.

19. The compound of claim 16, wherein Y is O.

20. The compound of claim 16, wherein X is O.

21. The compound of claim 16, wherein R.sup.3 and R.sup.4 independently of each other are selected from the group consisting of hydrogen, fluorine, methyl, trifluoromethyl and OCHF.sub.2, or R.sup.3 and R.sup.4 together with the carbon atom to which they are bound form a cyclopropyl ring.

22. The compound of claim 21, wherein R.sup.3 and R.sup.4 are both halogen.

23. The compound of claim 16, wherein W is NR.sup.2.

24. The compound of claim 16, wherein R.sup.2 is hydrogen, CH(O), C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy, C.sub.2-C.sub.6-alkenyl, propargyl, C.sub.3-C.sub.8-cycloalkyl, C.sub.3-C.sub.8-cycloalkenyl, C.sub.3-C.sub.8-cycloalkyl-C.sub.1-C.sub.4-alkyl, phenyl, C.sub.1-C.sub.6-alkylamino or diC.sub.1-C.sub.6-alkylamino; and wherein any of the aliphatic or cyclic groups are unsubstituted or substituted with 1, 2, 3, 4 or up to the maximum possible number of identical or different radicals selected from the group consisting of halogen, cyano, C.sub.1-C.sub.6-alkyl and C.sub.1-C.sub.6-alkoxy.

25. The compound of claim 16, wherein R.sup.1 is hydrogen, C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy, C.sub.3-C.sub.8-cycloalkyl, phenyl or benzyl, and wherein any of the aliphatic or cyclic groups are substituted with 1, 2 or 3 of identical or different groups R.sup.1a; wherein R.sup.1a is selected from fluorine, chlorine, cyano, methyl, ethyl, methoxy, trifluoromethyl, trifluoromethoxy, difluoromethyl, difluoromethoxy and cyclopropyl.

26. Intermediate compounds of the formulae IV or V, ##STR00025## wherein the variables A, Y, W, R.sup.1, R.sup.3 and R.sup.4 are as defined in claim 16 for compounds of the formula I.

27. An agrochemical composition, which comprises an auxiliary and at least one compound of the formula I of claim 16 or an N-oxide or an agriculturally acceptable salt thereof.

28. An agrochemical composition of claim 27 further comprising seed, wherein the amount of the compound of the formula I, or an N-oxide, or an agriculturally acceptable salt thereof, is from 0.1 g to 10 kg per 100 kg of seed.

29. A method for combating phytopathogenic harmful fungi, which process comprises treating the fungi, the plants, the soil or seeds to be protected against fungal attack, with an effective amount of at least one compound of formula I of claim 16 or an N-oxide or an agriculturally acceptable salt thereof.

30. A method for combating phytopathogenic harmful fungi, which process comprises treating the fungi, the plants, the soil or seeds to be protected against fungal attack, with an effective amount of the agrochemical composition as defined in claim 27.

31. The compound of claim 17, wherein Y is O.

32. The compound of claim 17, wherein X is O.

33. The compound of claim 17, wherein R.sup.3 and R.sup.4 independently of each other are selected from the group consisting of hydrogen, fluorine, methyl, trifluoromethyl and OCHF.sub.2, or R.sup.3 and R.sup.4 together with the carbon atom to which they are bound form a cyclopropyl ring.

34. The compound of claim 17, wherein W is NR.sup.2.

35. The compound of claim 17, wherein R.sup.2 is hydrogen, CH(O), C.sub.1-C.sub.6-alkyl, C.sub.1-C.sub.6-alkoxy, C.sub.2-C.sub.6-alkenyl, propargyl, C.sub.3-C.sub.8-cycloalkyl, C.sub.3-C.sub.8-cycloalkenyl, C.sub.3-C.sub.8-cycloalkyl-C.sub.1-C.sub.4-alkyl, phenyl, C.sub.1-C.sub.6-alkylamino or diC.sub.1-C.sub.6-alkylamino; and wherein any of the aliphatic or cyclic groups are unsubstituted or substituted with 1, 2, 3, 4 or up to the maximum possible number of identical or different radicals selected from the group consisting of halogen, cyano, C.sub.1-C.sub.6-alkyl and C.sub.1-C.sub.6-alkoxy.

Description

I. SYNTHESIS EXAMPLES

Example 1: Preparation of 2,2-difluoro-N-methyl-2-[4-[5-(trifluoromethyl)-1,2,4-oxadiazol-3-yl]phenoxy]acetamide (I-1)

[0467] ##STR00022##

I.1) Ethyl 2-(4-cyanophenoxy)-2,2-difluoro-acetate

[0468] To the solution of 4-hydroxybenzonitrile (1 g, 8.4 mmol) in DMF (30 mL) was added 1,8-di-azabicyclo[5.4.0]undec-7-ene (DBU) (2.6 g, 16.8 mmol) and ethyl 2-bromo-2,2-difluoro-acetate (3.4 g, 16.8 mmol) at 25 C. and stirring was continued for 16 h. The reaction mixture was diluted with brine (50 mL) and extracted with MTBE. The organic layer was successively washed with a saturated aqueous solution of sodium chloride, dried over sodium sulfate and freed from solvent under reduced pressure. Flash chromatography on silica gel using cyclohexane-ethyl acetate provided the titled product (1.65 g) as colorless oil.

[0469] 1H NMR (CDCl3): [ppm]=1.39 (t, J=7.15 Hz, 3H) 4.42 (q, J=7.15 Hz, 2H) 7.34 (d, J=8.78 Hz, 2H) 7.66-7.77 (m, 2H).

I.2) 2-(4-cyanophenoxy)-2,2-difluoro-N-methyl-acetamide

[0470] The solution of methylamine in THF (6 mL, 12 mmol) in dichloromethane (DCM) (30 mL) was added trimethylaluminium (6 mL, 12 mmol) dropwise, the mixture was stirred for 1 h, then ethyl 2-(4-cyanophenoxy)-2,2-difluoro-acetate (1.45 g, 6 mmol) in DCM was added dropwise and the mixture was stirred for 16 h at 25 C. The reaction mixture was quenched with water (100 mL), extracted with DCM (50 mL) and ethyl acetate (EtOAc, 100 mL). The organic layer was successively washed with a saturated aqueous solution of sodium chloride, dried over sodium sulfate and freed from solvent under reduced pressure to provide the titled product (1.65 g) as a yellow solid. 1H NMR (CDCl3): [ppm]=2.91 (d, J=5.02 Hz, 3H) 6.46 (br d, J=12.30 Hz, 1H) 7.27 (d, J=8.78 Hz, 2H) 7.58-7.67 (m, 2H).

I.3) 2,2-Difluoro-2-[4-[(Z)N-hydroxycarbamimidoyl]phenoxy]-N-methyl-acetamide

[0471] 2-(4-Cyanophenoxy)-2,2-difluoro-N-methyl-acetamide (1.25 g, 0.006 mol), hydroxylamine hydrochloride (1.2 g, 0.017 mol) and triethylamine (1.72 g, 0.017 mol) were dissolved in ethanol (50 mL). The reaction mixture was heated at 70 C. for 16 h. The solvent was removed to give 5.68 g of a white solid. The crude material was used without further purification.

[0472] 1H NMR (CDCl3): [ppm]=2.85 (s, 3H) 7.19 (d, J=8.66 Hz, 2H) 7.58 (d, J=8.78 Hz, 2H).

I.4) 2,2-Difluoro-N-methyl-2-[4-[5-(trifluoromethyl)-1,2,4-oxadiazol-3-yl]phenoxy]acetamide

[0473] 2,2-Difluoro-2-[4-[(Z)N-hydroxycarbamimidoyl]phenoxy]-N-methyl-acetamide (5.68 g, 0.022 mol) was dissolved in dimethylacetamide (100 ml). Trifluoroacetic acid anhydride (TFAA) was added (9.25 g, 0.044 mol) dropwise at 0 C. and the mixture was stirred for 1 h at 25 C. The reaction mixture was diluted with brine (100 mL) and extracted with EtOAc (50 mL). The organic layer was successively washed with a saturated aqueous solution of sodium chloride, dried over sodium sulfate and freed from solvent. The residue was purified by prep-HPLC (gradient elution, water/ACN both containing 0.1% TFA) to give 1.4 g of the desired product as a white solid.

[0474] 1H NMR (CDCl.sub.3): [ppm]=3.00 (d, J=5.02 Hz, 3H) 6.53 (br s, 1H) 7.39 (d, J=8.66 Hz, 2H) 8.11-8.21 (m, 2H).

[0475] With due modification of the starting compounds, the procedures shown in the synthesis examples below were used to obtain further compounds I. The resulting compounds, together with physical data, are listed in Table I below.

TABLE-US-00002 TABLE I Compounds I-1 to I-19 of formula I.1 with physical data, wherein the meaning of R.sup.1, R.sup.3, R.sup.4, X and W are as defined in each line. [00023] Ex. HPLC R.sub.t m.p. [C]; no R.sup.3, R.sup.4 X W R.sup.1 (min)* .sup.1H-NMR () I-1 F, F O NH CH.sub.3 1.17 110; [ppm] = 3.00 (d, J = 5.02 Hz, 3H) 6.53 (br s, 1H) 7.39 (d, J = 8.66 Hz, 2H) 8.11-8.21 (m, 2 H) I-2 F, F O NCH.sub.3 CH.sub.3 1.25 54; [ppm] = 0.6-0.9 (m, 4H); 3.2 (s, 3H); 7.3 (m, 2H); 8.3 (m, 2H) I-3 F, F O NCH.sub.3 cyclopropyl 1.33 47 I-4 F, F O NH cyclopropyl 1.21 108; 5 [ppm] = 0.6-0.9 (m, 4H); 2.85 (m, 1H); 7.4 (m, 2H); 8.2 (m, 2H) I-5 F, F O NH isopropyl 1.24 104 I-6 F, F O NH cycloheptyl 1.31 120 I-7 F, F O NCH.sub.3 CH.sub.2CH.sub.3 1.28 I-8 F, F O NH cyclobutyl 1.27 114 I-9 F, F O NH C(CH.sub.3).sub.3 1.28 64 I-10 H, H O NCH.sub.3 CH.sub.3 1.05 I-11 H, H O NH CH.sub.3 1.08 I-12 CH.sub.3, CH.sub.3 O NH CH.sub.3 1.17 I-13 CH.sub.3, CH.sub.3 O NCH.sub.3 CH.sub.3 1.28 I-14 H, CH.sub.3 O NH CH.sub.3 1.10 I-15 H, CH.sub.3 O NCH.sub.3 CH.sub.3 1.13 I-16 F, F O NH CH.sub.2CF.sub.3 1.27 101 I-17 F, F S NH cyclopropyl 1.33 I-18 F, F S NH CH.sub.3 1.28 115 I-19 Br, CF.sub.3 O NCH.sub.3 CH.sub.3 1.38 Legend of Table I: m.p. = melting point; R.sub.t = HPLC Retention time. *HPLC: High Performance Liquid Chromatography; HPLC-column Kinetex XB C18 1,7 (50 x 2,1 mm); eluent: acetonitrile/water + 0.1% trifluoroacetic acid (gradient from 5:95 to 100:0 in 1.5 min at 60 C, flow gradient from 0.8 to 1.0 ml/min in 1.5 min). MS: Quadrupol Electrospray Ionisation, 80 V (positive mode).

II. BIOLOGICAL EXAMPLES FOR FUNGICIDAL ACTIVITY

[0476] Glass House Trials

[0477] The fungicidal action of the compounds of formula I was demonstrated by the following experiments: spray solutions were prepared in several steps. A mixture was prepared of acetone and/or dimethylsulfoxide and the wetting agent/emulsifier Wettol, which is based on ethoxylated alkylphenoles, in a relation (volume) solvent-emulsifier of 99 to 1 was added to the compound to give a total of 5 ml. Water was then added to a total volume of 100 ml. This stock solution was diluted with the described solvent-emulsifier-water mixture to the given concentration.

[0478] II.1) Curative Control of Soy Bean Rust on Soy Beans Caused by Phakopsora pachyrhizi

[0479] Leaves of pot-grown soy bean seedlings were inoculated with spores of Phakopsora pachyrhizi To ensure the success of the artificial inoculation, the plants were transferred to a humid chamber with a relative humidity of about 95% and 20 to 24 C. for 24 hours. The next day the plants were cultivated for 3 days in a greenhouse chamber at 23 to 27 C. and a relative humidity between 60 and 80%. Then the plants were sprayed to run-off with an aqueous suspension, containing the concentration of active ingredient or their mixture as described below. The plants were allowed to air-dry. Then the trial plants were cultivated for 14 days in a greenhouse chamber at 23 to 27 C. and a relative humidity between 60 and 80%. The extent of fungal attack on the leaves was visually assessed as % diseased leaf area.

[0480] In this test, the plants which had been treated with 63 ppm of the active compound I-1, I-4, I-5, I-8, I-10, I-11, I-12, I-13, I-14, I-16 and 1-18 showed a diseased leaf area of at most 12%, whereas the untreated plants showed 90% diseased leaf area.

II.2) Protective Control of Soy Bean Rust on Soy Beans Caused by Phakopsora pachyrhizi

[0481] Leaves of pot-grown soy bean seedlings were sprayed to run-off with an aqueous suspension, containing the concentration of active ingredient or their mixture as described below. The plants were allowed to air-dry. The trial plants were cultivated for 2 days in a greenhouse chamber at 23 to 27 C. and a relative humidity between 60 and 80%. Then the plants were inoculated with spores of Phakopsora pachyrhizi To ensure the success the artificial inoculation, the plants were transferred to a humid chamber with a relative humidity of about 95% and 20 to 24 C. for 24 hours. The trial plants were cultivated for fourteen days in a greenhouse chamber at 23 to 27 C. and a relative humidity between 60 and 80%. The extent of fungal attack on the leaves was visually assessed as % diseased leaf area.

[0482] In this test, the plants which had been treated with 63 ppm of the active compound I-1, I-2, I-3, I-4, I-5, I-6, I-7, I-8, I-9, I-10, I-11, I-12, I-13, I-14, I-15, I-16, I-17, I-18 and 1-19 showed a diseased leaf area of at most 2%, whereas the untreated plants showed 90% diseased leaf area.

II.3) Curative Control of Brown Rust on Wheat Caused by Puccinia recondita

[0483] The first two developed leaves of pot-grown wheat seedling were dusted with spores of Puccinia recondita. To ensure the success the artificial inoculation, the plants were transferred to a humid chamber without light and a relative humidity of 95 to 99% and 20 to 24 C. for 24 hours. The next day the plants were cultivated for 3 days in a greenhouse chamber at 20 to 24 C. and a relative humidity between 65 and 70%. Then the plants were sprayed to run-off with an aqueous suspension, containing the concentration of active ingredient or their mixture as described below. The plants could air-dry. Then the trial plants were cultivated for 8 days in a greenhouse chamber at 20 to 24 C. and a relative humidity between 65 and 70%. The extent of fungal attack on the leaves was visually assessed as % diseased leaf area.

[0484] In this test, the plants which had been treated with 63 ppm of the active compound 1-2 showed a diseased leaf area of 3%, whereas the untreated plants showed 80% diseased leaf area.

[0485] In this test, the plants which had been treated with 63 ppm of the active compound I-1, I-4, I-5, I-10 and 1-14 showed a diseased leaf area of at most 9%, whereas the untreated plants showed 90% diseased leaf area.

II.4) Preventative Control of Brown Rust on Wheat Caused by Puccinia recondita

[0486] The first two developed leaves of pot-grown wheat seedling were sprayed to run-off with an aqueous suspension, containing the concentration of active ingredient or their mixture as described below. The next day the plants were inoculated with spores of Puccinia recondita. To ensure the success the artificial inoculation, the plants were transferred to a humid chamber without light and a relative humidity of 95 to 99% and 20 to 24 C. for 24 hours. Then the trial plants were cultivated for 6 days in a greenhouse chamber at 20 to 24 C. and a relative humidity between 65 and 70%. The extent of fungal attack on the leaves was visually assessed as % diseased leaf area.

[0487] In this test, the plants which had been treated with 63 ppm of the active compound 1-2 showed a diseased leaf area of 2%, whereas the untreated plants showed 80% diseased leaf area.

[0488] In this test, the plants which had been treated with 63 ppm of the active compound I-1, I-3, I-4, I-10, I-11, I-12, I-14 and I-17 showed a diseased leaf area of at most 13%, whereas the untreated plants showed 90% diseased leaf area.