Use of substituted dithiine-dicarboximides for combating phytopathogenic fungi

The present invention relates to the use of dithiine-dicarboximide compounds of formula I as defined in the description, and the N-oxides, and salts thereof for combating harmful fungi and seed coated with at least one such compound. The invention also relates to novel dithiine-dicarboximides, processes and intermediates for preparing these compounds and also to compositions comprising at least one such compound.

The present invention relates to the use of substituted dithiine-dicarboximides and the N-oxides and the salts thereof for combating phytopathogenic fungi, and to seeds treated with at least one such compound. The invention also relates to novel substituted dithiine-dicarboximide compounds, processes for preparing these compounds and to compositions comprising at least one such compound.

The use of certain substituted dithiine-tetracarboximides of the formula

for controlling phytopathogenic fungi is known from WO 2010/043319 and 2011/029551. The compounds according to the present invention differ from those described in the abovemention publications by the specific group fused to one side of the dithiine moiety.

Further, a substituted pyrrolo[3,4-b]quinoxaline-1,3-dione derivative of the formula

wherein R1is a substituted phenyl with moderate antifungal activity is disclosed in Affinidad 60(503), 81-87 (2003). The compounds according to the present invention differ from this in the abovementioned publication by the specific R1substituent as defined herein and only allowing a 4,9-dihydropyrrolo instead of the pyrrolo moiety.

In many cases, in particular at low application rates, the fungicidal activity of the known fungicidal compounds is unsatisfactory. Based on this, it was an object of the present invention to provide compounds having improved activity and/or a broader activity spectrum against phytopathogenic harmful fungi.

This object is achieved by the use of certain substituted dithiine-dicarboximides having good fungicidal activity against phytopathogenic harmful fungi.

Accordingly, the present invention relates to the use of compounds of formula I

Further, the preparation of certain substituted pyrrolo-oxazine-diones has been described in Synth. Commun. 39(1), 70-84, (2009).

Further, the preparation of certain substituted pyrrolo-thiazine-diones, inter alia 2-methyl-9H-benzo[b]pyrrolo[3,4-e][1,4]thiazine-1,3-dione and 9-acetyl-2-methyl-9H-benzo[b]pyrrolo[3,4-e][1,4]thiazine-1,3-dione, have been disclosed in Nippon Kagaku Kaishi (1992), (11), 1392-6 and Zeitschrift fuer Chemie (1987), 27(6), 211-12.

Therefore, according to a second aspect, the invention also provides novel compounds of formula I having good fungicidal activity against phytopathogenic harmful fungi:

The term “compounds I” refers to compounds of formula I. Likewise, this terminology applies to all sub-formulae, e.g. “compounds I.A” refers to compounds of formula I.A or “compounds V” refers to compounds of formula V, etc.

The compounds I can be by various routes in analogy to prior art processes known per se for preparing (cf. Tetrahedron Lett. 49, (1969), 4273-4274) and, advantageously, by the synthesis shown in the following schemes and in the experimental part of this application.

In a first step, for example (cf. Synthetic Commun. 36, (2006), 3591-3597; Revue Roumaine de Chimie 50, (2005), 601-607; Chem. Ind. London 4, (1991), 130; JP 571200502; DD 218261; DD 224031), dichloromaleic anhydride II is reacted, in a first step, with an amine III, if appropriate in the presence of a diluent to obtain maleic imides IV:

If appropriate, the resulting compounds I can subsequently be oxidized e.g. with nitric acid to form compounds I, wherein X is S═O. If individual compounds I cannot be obtained by the routes described above, they can be prepared by derivatization of other compounds I.

The N-oxides may be prepared from the compounds I according to conventional oxidation methods, e.g. by treating compounds I with an organic peracid such as metachloroperbenzoic acid (cf. WO 03/64572 or J. Med. Chem. 38(11), 1892-903, 1995); or with inorganic oxidizing agents such as hydrogen peroxide (cf. J. Heterocyc. Chem. 18(7), 1305-8, 1981) or oxone (cf. J. Am. Chem. Soc. 123(25), 5962-5973, 2001). The oxidation may lead to pure mono-N-oxides or to a mixture of different N-oxides, which can be separated by conventional methods such as chromatography.

If the synthesis yields mixtures of isomers, a separation is generally not necessarily required since in some cases the individual isomers can be interconverted during workup for use or during application (e.g. under the action of light, acids or bases). Such conversions may also take place after use, e.g. in the treatment of plants in the treated plant, or in the harmful fungus to be controlled.

In the definitions of the variables given above, collective terms are used which are generally representative for the substituents in question. The term “Cn-Cm” indicates the number of carbon atoms possible in each case in the substituent or substituent moiety in question.

The term “halogen” refers to fluorine, chlorine, bromine and iodine.

The term “C1-C6-alkoxy” refers to a straight-chain or branched alkyl group having 1 to 4 carbon atoms which is bonded via an oxygen, at any position in the alkyl group, e.g. OCH3, OCH2CH3, O(CH2)2CH3, 1-methylethoxy, O(CH2)3CH3, 1-methylpropoxy, 2-methylpropoxy or 1,1-dimethylethoxy, O(CH2)4CH3or O(CH2)5CH3. Likewise, the term “C1-C4-alkoxy” refers to a straight-chain or branched alkyl group having 1 to 4 carbon atoms which is bonded via an oxygen, at any position in the alkyl group.

The term “C1-C4-alkylamino” refers to an amino radical carrying one C1-C4-alkyl group as substituent, e.g. methylamino, ethylamino, propylamino, 1-methylethylamino, butylamino, 1-methylpropylamino, 2-methylpropylamino, 1,1-dimethylethylamino and the like. Likewise, the term “C1-C6-alkylamino” refers to an amino radical carrying one C1-C6-alkyl group as substituent.

The term “di(C1-C4-alkyl)amino” refers to an amino radical carrying two identical or different C1-C4-alkyl groups as substituents, e.g. dimethylamino, diethylamino, di-n-propylamino, diisopropylamino, N-ethyl-N-methylamino, N-(n-propyl)-N-methylamino, N-(isopropyl)-N methylamino, N-(n-butyl)-N-methylamino, N-(n-pentyl)-N-methylamino, N-(2-butyl)-N methylamino, N-(isobutyl)-N-methylamino, and the like. Likewise, the term “di(C1-C6-alkyl)amino” refers to an amino radical carrying two identical or different C1-C6-alkyl groups as substituents.

The term “C1-C4-alkylcarbonyl” refers to a C1-C6-alkyl radical which is attached via a carbonyl group. The term “(C1-C6-alkoxy)carbonyl” refers to a C1-C6-alkoxy radical which is attached via a carbonyl group.

The term “C1-C6-alkylaminocarbonyl” refers to a C1-C6-alkylamino radical which is attached via a carbonyl group. Likewise, the term “di(C1-C6-alkyl)aminocarbonyl” refers to a di(C1-C6)alkylamino radical which is attached via a carbonyl group.

The term “C2-C4-alkenyl” refers to a straight-chain or branched unsaturated hydrocarbon radical having 2 to 4 carbon atoms and a double bond in any position, e.g. ethenyl, 1-propenyl, 2-propenyl(allyl), 1-methylethenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methyl-1-propenyl, 2-methyl-1-propenyl, 1-methyl-2-propenyl, 2-methyl-2-propenyl. Likewise, the term “C2-C6-alkenyl” refers to a straight-chain or branched unsaturated hydrocarbon radical having 2 to 6 carbon atoms and a double bond in any position.

The term “C2-C4-alkynyl” refers to a straight-chain or branched unsaturated hydrocarbon radical having 2 to 4 carbon atoms and containing at least one triple bond, such as ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methyl-2-propynyl. Likewise, the term “C2-C6-alkynyl” refers to a straight-chain or branched unsaturated hydrocarbon radical having 2 to 6 carbon atoms and at least one triple bond.

The term “C3-C6-cycloalkyl” refers to monocyclic, bicyclic, saturated hydrocarbon radicals having 3 to 6 carbon ring members, such as cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.

Likewise, the term “C3-C6-cycloalkenyl” refers to unsaturated hydrocarbon radicals having 3 to 6 carbon ring members and a double bond in any position, such as cyclopropenyl, cyclobutenyl, cyclopentenyl or cyclohexenyl.

The term “C3-C6-cycloalkyl-C1-C6-alkyl” refers to alkyl having 1 to 6 carbon atoms (as defined above), wherein one hydrogen atom of the alkyl radical is replaced by a cycloalkyl radical having 3 to 6 carbon atoms (as defined above).

Agriculturally acceptable salts of compounds I encompass especially the salts of those cations or the acid addition salts of those acids whose cations and anions, respectively, have no adverse effect on the fungicidal action of the compounds I. Suitable cations are thus in particular the ions of the alkali metals, preferably sodium and potassium, of the alkaline earth metals, preferably calcium, magnesium and barium, of the transition metals, preferably manganese, copper, zinc and iron, and also the ammonium ion which, if desired, may carry one to four C1-C4-alkyl substituents and/or one phenyl or benzyl substituent, preferably diisopropylammonium, tetramethylammonium, tetrabutylammonium, trimethylbenzylammonium, furthermore phosphonium ions, sulfonium ions, preferably tri(C1-C4-alkyl)sulfonium, and sulfoxonium ions, preferably tri(C1-C4-alkyl)sulfoxonium. Anions of useful acid addition salts are primarily chloride, bromide, fluoride, hydrogensulfate, sulfate, dihydrogenphosphate, hydrogenphosphate, phosphate, nitrate, bicarbonate, carbonate, hexafluorosilicate, hexafluorophosphate, benzoate, and the anions of C1-C4-alkanoic acids, preferably formate, acetate, propionate and butyrate. They can be formed by reacting a compound of formula I with an acid of the corresponding anion, preferably of hydrochloric acid, hydrobromic acid, sulfuric acid, phosphoric acid or nitric acid.

The compounds of formula I can be present in atropisomers arising from restricted rotation about a single bond of asymmetric groups. They also form part of the subject matter of the present invention.

Depending on the substitution pattern, the compounds of formula I and their N-oxides may have one or more centers of chirality, in which case they are present as pure enantiomers or pure diastereomers or as enantiomer or diastereomer mixtures. Both, the pure enantiomers or diastereomers and their mixtures are subject matter of the present invention.

In respect of the variables, the embodiments of the intermediates correspond to the embodiments of the compounds I.

Preference is given to those compounds I and where applicable also to compounds of all sub-formulae provided herein, e.g. formulae I.A, I.B to I.G and to the intermediates such as compounds II, III, IV and V, wherein the substituents and variables (such as n, X1, X2, R, R1, R2, RA, RBand Ra) have independently of each other or more preferably in combination the following meanings:

One embodiment of the invention relates to compounds I, wherein X1and X2are S and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.A

Another embodiment relates to compounds I, wherein X1is S═O and X2is S and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.B

A further embodiment relates to compounds I, wherein X1and X2are O and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.C

A further embodiment relates to compounds I, wherein X1and X2are NH and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.D

A further embodiment relates to compounds I, wherein X1and X2are NCH3and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.E

A further embodiment relates to compounds I, wherein X1and X2are N(CO)CH3and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.F

A further embodiment relates to compounds I, wherein X1is S and X2is NH and wherein R2ato R2dhave one of the definitions of R2or are hydrogen, which are of formula I.G

A further embodiment relates to compounds I, wherein X1and X2are identical.

A further embodiment relates to compounds I, wherein X1and X2together cannot be NR and S (to exclude combinations X1═NR, X2═S and X1═S, X2═NR).

A further embodiment relates to compounds I, wherein X1and X2cannot be NH and S (to exclude combinations X1═NH, X2═S and X1═S, X2═NH).

A further embodiment relates to compounds I, wherein X1and X2cannot be NH and O (to exclude combinations X1═NH, X2═O and X1═O, X2═NH).

In one embodiment, R1is selected from hydrogen, C1-C6-alkyl and C1-C6-alkoxy, more preferably selected from hydrogen, methyl, ethyl, methoxy and ethoxy, even more preferably from hydrogen and methyl.

In a further embodiment, n is preferably selected from 0, 1 and 2; even more preferably from 0 and 1, in particular 1. Whenever n is 1, R2is preferably in position of R2bor R2cas depicted in formulae I.A to I.C. Whenever n is 1, R2is preferably identical to R1.

In a further embodiment, n is 0.

In a further embodiment, R2is selected from hydrogen, halogen, CN, nitro, C1-C6-alkyl and C1-C6-halogenalkyl, more preferably selected from hydrogen, methyl, CN and nitro and even more preferably from hydrogen and methyl.

In a further embodiment, R2is substituted by 1 to 3 halogen, preferably selected from Cl and F.

In a further embodiment, R2is CF3.

A skilled person will readily understand that the preferences given in connection with compounds I apply for formulae I.A, I.B, I.C, I.D, I.E and I.F as defined above.

With respect to their use, particular preference is given to the 20480 compounds of formulae I.A, I.B, IC. I.D, I.E, I.F and I.G compiled in the tables 1 to 32 below. Here, the groups mentioned in the Tables for a substituent are furthermore, independently of the combination wherein they are mentioned, a particularly preferred embodiment of the substituent in question.

Table 1: Compounds I to 640 of formula I.A, wherein R1is hydrogen and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Table 2: Compounds 641 to 1280 of formula I.A, wherein R1is methyl and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Table 3: Compounds 1281 to 1920 of formula I.A, wherein R1is ethyl and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Table 4: Compounds 1921 to 2560 of formula I.A, wherein R1is methoxy and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 5 to 8: Compounds 2561 to 5120 of formula I.B, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 9 to 12: Compounds 5121 to 7680 of formula I.B, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 13 to 16: Compounds 7681 to 10240 of formula I.C, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 17 to 20: Compounds 10241 to 12800 of formula I.D, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 21 to 24: Compounds 12801 to 15360 of formula I.E, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 25 to 28: Compounds 15361 to 17920 of formula I.F, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

Tables 29 to 32: Compounds 17921 to 20480 of formula I.G, wherein R1is defined as in Tables 1 to 4, and the meaning of R2a, R2b, R2cand R2dfor each compound corresponds to one line of table A.

The compounds I and the compositions according to the invention, respectively, are suitable as fungicides. They are distinguished by an outstanding effectiveness against a broad spectrum of phytopathogenic fungi, including soil-borne fungi, which derive especially from the classes of the Plasmodiophoromycetes, Peronosporomycetes (syn. Oomycetes), Chytridiomycetes, Zygomycetes, Ascomycetes, Basidiomycetes and Deuteromycetes (syn. Fungi imperfecti). Some are systemically effective and they can be used in crop protection as foliar fungicides, fungicides for seed dressing and soil fungicides. Moreover, they are suitable for controlling harmful fungi, which inter alia occur in wood or roots of plants.

The compounds I and the compositions according to the invention are particularly important in the control of a multitude of phytopathogenic fungi on various cultivated plants, such as cereals, e.g. wheat, rye, barley, triticale, oats or rice; beet, e.g. sugar beet or fodder beet; fruits, such as pomes, stone fruits or soft fruits, e.g. apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries, blackberries or gooseberries; leguminous plants, such as lentils, peas, alfalfa or soybeans; oil plants, such as rape, mustard, olives, sunflowers, coconut, cocoa beans, castor oil plants, oil palms, ground nuts or soybeans; cucurbits, such as squashes, cucumber or melons; fiber plants, such as cotton, flax, hemp or jute; citrus fruit, such as oranges, lemons, grapefruits or mandarins; vegetables, such as spinach, lettuce, asparagus, cabbages, carrots, onions, tomatoes, potatoes, cucurbits or paprika; lauraceous plants, such as avocados, cinnamon or camphor; energy and raw material plants, such as corn, soybean, rape, sugar cane or oil palm; corn; tobacco; nuts; coffee; tea; bananas; vines (table grapes and grape juice grape vines); hop; turf; sweet leaf (also called Stevia); natural rubber plants or ornamental and forestry plants, such as flowers, shrubs, broad-leaved trees or evergreens, e.g. conifers; and on the plant propagation material, such as seeds, and the crop material of these plants.

The term “plant propagation material” is to be understood to denote all the generative parts of the plant such as seeds and vegetative plant material such as cuttings and tubers (e.g. potatoes), which can be used for the multiplication of the plant. This includes seeds, roots, fruits, tubers, bulbs, rhizomes, shoots, sprouts and other parts of plants, including seedlings and young plants, which are to be transplanted after germination or after emergence from soil. These young plants may also be protected before transplantation by a total or partial treatment by immersion or pouring.

Preferably, treatment of plant propagation materials with compounds I and compositions thereof, respectively, is used for controlling a multitude of fungi on cereals, such as wheat, rye, barley and oats; rice, corn, cotton and soybeans.

The term “cultivated plants” is to be understood as including plants which have been modified by breeding, mutagenesis or genetic engineering including but not limiting to agricultural biotech products on the market or in development (cf. http://ceragmc.org/, see GM crop database therein). Genetically modified plants are plants, which genetic material has been so modified by the use of recombinant DNA techniques that under natural circumstances cannot readily be obtained by cross breeding, mutations or natural recombination. Typically, one or more genes have been integrated into the genetic material of a genetically modified plant in order to improve certain properties of the plant. Such genetic modifications also include but are not limited to targeted posttranslational modification of protein(s), oligo- or polypeptides e.g. by glycosylation or polymer additions such as prenylated, acetylated or farnesylated moieties or PEG moieties.

The compounds I and compositions thereof, respectively, are particularly suitable for controlling the following plant diseases:

The compounds I and compositions thereof, respectively, may be used for improving the health of a plant. The invention also relates to a method for improving plant health by treating a plant, its propagation material and/or the locus where the plant is growing or is to grow with an effective amount of compounds I and compositions thereof, respectively.

The term “plant health” is to be understood to denote a condition of the plant and/or its products which is determined by several indicators alone or in combination with each other such as yield (e.g. increased biomass and/or increased content of valuable ingredients), plant vigor (e.g. improved plant growth and/or greener leaves (“greening effect”)), quality (e.g. improved content or composition of certain ingredients) and tolerance to abiotic and/or biotic stress. The above identified indicators for the health condition of a plant may be interdependent or may result from each other.

The compounds of formula I can be present in different crystal modifications whose biological activity may differ. They are likewise subject matter of the present invention.

The compounds I are employed as such or in form of compositions by treating the fungi or the plants, plant propagation materials, such as seeds, soil, surfaces, materials or rooms to be protected from fungal attack with a fungicidally effective amount of the active substances. The application can be carried out both before and after the infection of the plants, plant propagation materials, such as seeds, soil, surfaces, materials or rooms by the fungi.

Plant propagation materials may be treated with compounds I as such or a composition comprising at least one compound I prophylactically either at or before planting or transplanting.

The invention also relates to agrochemical compositions comprising an auxiliary and at least one compound I according to the invention.

An agrochemical composition comprises a fungicidally effective amount of a compound I. The term “effective amount” denotes an amount of the composition or of the compounds I, which is sufficient for controlling harmful fungi on cultivated plants or in the protection of materials and which does not result in a substantial damage to the treated plants. Such an amount can vary in a broad range and is dependent on various factors, such as the fungal species to be controlled, the treated cultivated plant or material, the climatic conditions and the specific compound I used.

The compositions are prepared in a known manner, such as described by Mollet and Grubemann, Formulation technology, Wiley VCH, Weinheim, 2001; or Knowles, New developments in crop protection product formulation, Agrow Reports DS243, T&F Informa, London, 2005.

Suitable anti-freezing agents are ethylene glycol, propylene glycol, urea and glycerin.

Suitable anti-foaming agents are silicones, long chain alcohols, and salts of fatty acids.

Suitable colorants (e.g. in red, blue, or green) are pigments of low water solubility and water-soluble dyes. Examples are inorganic colorants (e.g. iron oxide, titan oxide, iron hexacyanoferrate) and organic colorants (e.g. alizarin-, azo- and phthalocyanine colorants).

The agrochemical compositions generally comprise between 0.01 and 95%, preferably between 0.1 and 90%, and in particular between 0.5 and 75%, by weight of active substance. The active substances are employed in a purity of from 90% to 100%, preferably from 95% to 100% (according to NMR spectrum).

Solutions for seed treatment (LS), Suspoemulsions (SE), flowable concentrates (FS), powders for dry treatment (DS), water-dispersible powders for slurry treatment (WS), water-soluble powders (SS), emulsions (ES), emulsifiable concentrates (EC) and gels (GF) are usually employed for the purposes of treatment of plant propagation materials, particularly seeds. The compositions in question give, after two-to-tenfold dilution, active substance concentrations of from 0.01 to 60% by weight, preferably from 0.1 to 40%, in the ready-to-use preparations. Application can be carried out before or during sowing. Methods for applying compound I and compositions thereof, respectively, on to plant propagation material, especially seeds include dressing, coating, pelleting, dusting, soaking and in-furrow application methods of the propagation material. Preferably, compound I or the compositions thereof, respectively, are applied on to the plant propagation material by a method such that germination is not induced, e.g. by seed dressing, pelleting, coating and dusting.

When employed in plant protection, the amounts of active substances applied are, depending on the kind of effect desired, from 0.001 to 2 kg per ha, preferably from 0.005 to 2 kg per ha, more preferably from 0.05 to 0.9 kg per ha, and in particular from 0.1 to 0.75 kg per ha.

In treatment of plant propagation materials such as seeds, e.g. by dusting, coating or drenching seed, amounts of active substance of from 0.1 to 1000 g, preferably from 1 to 1000 g, more preferably from 1 to 100 g and most preferably from 5 to 100 g, per 100 kilogram of plant propagation material (preferably seeds) are generally required.

When used in the protection of materials or stored products, the amount of active substance applied depends on the kind of application area and on the desired effect. Amounts customarily applied in the protection of materials are 0.001 g to 2 kg, preferably 0.005 g to 1 kg, of active substance per cubic meter of treated material.

Various types of oils, wetters, adjuvants, fertilizer, or micronutrients, and further pesticides (e.g. herbicides, insecticides, fungicides, growth regulators, safeners) may be added to the active substances or the compositions comprising them as premix or, if appropriate not until immediately prior to use (tank mix). These agents can be admixed with the compositions according to the invention in a weight ratio of 1:100 to 100:1, preferably 1:10 to 10:1.

The user applies the composition according to the invention usually from a predosage device, a knapsack sprayer, a spray tank, a spray plane, or an irrigation system. Usually, the agrochemical composition is made up with water, buffer, and/or further auxiliaries to the desired application concentration and the ready-to-use spray liquor or the agrochemical composition according to the invention is thus obtained. Usually, 20 to 2000 liters, preferably 50 to 400 liters, of the ready-to-use spray liquor are applied per hectare of agricultural useful area.

According to one embodiment, individual components of the composition according to the invention such as parts of a kit or parts of a binary or ternary mixture may be mixed by the user himself in a spray tank and further auxiliaries may be added, if appropriate.

Mixing the compounds I or the compositions comprising them in the use form as fungicides with other fungicides results in many cases in an expansion of the fungicidal spectrum of activity being obtained or in a prevention of fungicide resistance development. Furthermore, in many cases, synergistic effects are obtained.

The present invention furthermore relates to agrochemical compositions comprising a mixture of at least one compound I (component 1) and at least one further active substance useful for plant protection, e.g. selected from the groups A) to O) (component 2), in particular one further fungicide, e.g. one or more fungicide from the groups A) to L), as described above, and if desired one suitable solvent or solid carrier. Those mixtures are of particular interest, since many of them at the same application rate show higher efficiencies against harmful fungi. Furthermore, combating harmful fungi with a mixture of compounds I and at least one fungicide from groups A) to L), as described above, is more efficient than combating those fungi with individual compounds I or individual fungicides from groups A) to L). By applying compounds I together with at least one active substance from groups A) to O) a synergistic effect can be obtained, i.e. more then simple addition of the individual effects is obtained (synergistic mixtures).

This can be obtained by applying the compounds I and at least one further active substance simultaneously, either jointly (e.g. as tank-mix) or separately, or in succession, wherein the time interval between the individual applications is selected to ensure that the active substance applied first still occurs at the site of action in a sufficient amount at the time of application of the further active substance(s). The order of application is not essential for working of the present invention.

In binary mixtures, i.e. compositions according to the invention comprising one compound I (component 1) and one further active substance (component 2), e.g. one active substance from groups A) to O), the weight ratio of component 1 and component 2 generally depends from the properties of the active substances used, usually it is in the range of from 1:100 to 100:1, regularly in the range of from 1:50 to 50:1, preferably in the range of from 1:20 to 20:1, more preferably in the range of from 1:10 to 10:1 and in particular in the range of from 1:3 to 3:1.

In ternary mixtures, i.e. compositions according to the invention comprising one compound I (component 1) and a first further active substance (component 2) and a second further active substance (component 3), e.g. two active substances from groups A) to O), the weight ratio of component 1 and component 2 depends from the properties of the active substances used, preferably it is in the range of from 1:50 to 50:1 and particularly in the range of from 1:10 to 10:1, and the weight ratio of component 1 and component 3 preferably is in the range of from 1:50 to 50:1 and particularly in the range of from 1:10 to 10:1.

Preference is given to mixtures comprising a compound of formula I (component 1) and at least one active substance selected from group C) (component 2) and particularly selected from metalaxyl, (metalaxyl-M) mefenoxam, ofurace.

Preference is given to mixtures comprising a compound of formula I (component 1) and at least one active substance selected from group D) (component 2) and particularly selected from benomyl, carbendazim, thiophanate-methyl, ethaboxam, fluopicolide, zoxamide, metrafenone, pyriofenone.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group E) (component 2) and particularly selected from cyprodinil, mepanipyrim, pyrimethanil.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group F) (component 2) and particularly selected from iprodione, fludioxonil, vinclozolin, quinoxyfen.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group G) (component 2) and particularly selected from dimethomorph, flumorph, iprovalicarb, benthiavalicarb, mandipropamid, propamocarb.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group H) (component 2) and particularly selected from copper acetate, copper hydroxide, copper oxychloride, copper sulfate, sulfur, mancozeb, metiram, propineb, thiram, captafol, folpet, chlorothalonil, dichlofluanid, dithianon.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group I) (component 2) and particularly selected from carpropamid and fenoxanil.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group J) (component 2) and particularly selected from acibenzolar-5-methyl, probenazole, tiadinil, fosetyl, fosetyl-aluminium, H3PO3and salts thereof.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group K) (component 2) and particularly selected from cymoxanil, proquinazid and N-methyl-2-{1-[(5-methyl-3-trifluoromethyl-1H-pyrazol-1-yl)-acetyl]-piperidin-4-yl}-N-[(1R)-1,2,3,4-tetrahydronaphthalen-1-yl]-4-thiazolecarboxamide.

Preference is also given to mixtures comprising a compound I (component 1) and at least one active substance selected from group L) (component 2) and particularly selected fromBacillus subtilisstrain NRRL No. B-21661,Bacillus pumilusstrain NRRL No. B-30087 andUlocladium oudemansii.

Accordingly, the present invention furthermore relates to compositions comprising one compound I (component 1) and one further active substance (component 2), which further active substance is selected from the column “Component 2” of the lines B-1 to B-372 of Table B.

A further embodiment relates to the compositions B-1 to B-372 listed in Table B, where a row of Table B corresponds in each case to a fungicidal composition comprising one of the in the present specification individualized compounds of formula I (component 1) and the respective further active substance from groups A) to O) (component 2) stated in the row in question. Preferably, the compositions described comprise the active substances in synergistically effective amounts.

The mixtures of active substances can be prepared as compositions comprising besides the active ingredients at least one inert ingredient by usual means, e.g. by the means given for the compositions of compounds I.

Concerning usual ingredients of such compositions reference is made to the explanations given for the compositions containing compounds I.

The mixtures of active substances according to the present invention are suitable as fungicides, as are the compounds of formula I. They are distinguished by an outstanding effectiveness against a broad spectrum of phytopathogenic fungi, especially from the classes of the Ascomycetes, Basidiomycetes, Deuteromycetes and Peronosporomycetes (syn. Oomycetes). In addition, it is referred to the explanations regarding the fungicidal activity of the compounds and the compositions containing compounds I, respectively.

SYNTHESIS EXAMPLES

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.

I. Preparation of compounds I

A stirred solution of 4-methylbenzene-1,2-dithiol (0.5 g) in anhydrous DMF (50 ml) was treated with K2CO3and 3,4-dichloro-1-methyl-pyrrole-2,5-dione (0.73 g) and stirred for about 7 hours at 80° C. The reaction mixture was poured into water and extracted with MTBE. The combined organic phases were washed once with water and after removal of the solvent under reduced pressure the crude product (0.85 g) was purified by flash column chromatography on silica gel (cyclohexane/ethyl acetate 9:1) to yield the compound ex. I-2 (0.25 g); m.p.: 171-176° C.

III. Examples of the Action Against Harmful Fungi

The fungicidal action of the compounds of the formula I was demonstrated by the following experiments:

The active substances were formulated separately as a stock solution in dimethyl sulfoxide (DMSO) at a concentration of 10 000 ppm.

Use Example 1

Activity Against the Rice Blast PathogenPyricularia oryzae

The stock solution was pipetted into a microtiter plate (MTP) and diluted to the stated active substance concentration using an aequous biomalt—or yeast—beactopeptonesodium acetate solution. An aqueous spore suspension ofPyricularia oryzaewas then added. The plates were placed in a water vapor-saturated chamber at temperatures of 18° C. Using an absorption photometer, the microtiter plates were measured at 405 nm on day 7 after the inoculation. The measured parameters were compared to the growth of the active substance-free control variant (=100%) and the fungus- and active substance-free blank value to determine the relative growth in % of the pathogens in the individual active substances.

In this test, the sample which had been treated with 125 ppm of the active substance from example I-1 showed up to at most 5% growth of the pathogen.

Use Example 2

Activity Against the Grey Mold PathogenBotrytis cinerea

The stock solution was pipetted into a microtiter plate (MTP) and diluted to the stated active substance concentration using an aequous biomalt—or yeast—beactopeptonesodium acetate solution. An aqueous spore suspension ofBotrytis cinereawas then added. The plates were placed in a water vapor-saturated chamber at temperatures of 18° C. Using an absorption photometer, the microtiter plates were measured at 405 nm on day 7 after the inoculation. The measured parameters were compared to the growth of the active substance-free control variant (=100%) and the fungus- and active substance-free blank value to determine the relative growth in % of the pathogens in the individual active substances.

In this test, the sample which had been treated with 125 ppm of the active substance from examples I-1 showed up to at most 5% growth of the pathogen.

The stock solution were prepared: a mixture of acetone and/or dimethylsulfoxide and the wetting agent/emulsifier Wettol, which is based on ethoxylated alkylphenoles, in a relation solvent-emulsifier of 99 to 1 (v/v) was added to 25 mg of the compound to give a total of 5 ml. Water was then added to total volume of 100 ml.

This stock solution was diluted with the described solvent-emulsifier-water mixture to the given concentration.

Use Example 3

Preventative Control of Leaf Blotch on Wheat Caused bySeptoria tritici

Leaves of pot-grown wheat seedling were sprayed to run-off with an aqueous suspension of the active compound or their mixture, prepared as described. The plants were allowed to air-dry. At the following day the plants were inoculated with an aqueous spore suspension ofSeptoria tritici. Then the trial plants were immediately transferred to a humid chamber at 18-22° C. and a relative humidity close to 100%. After 4 days the plants were transferred to a chamber with 18-22° C. and a relative humidity close to 70%. After 4 weeks the extent of fungal attack on the leaves was visually assessed as % diseased leaf area.

In this test, the plants which had been treated with 1000 ppm of the active substance from example I-3 showed an infection of less than or equal to 5% whereas the untreated plants were 90% infected.