GB2046249A - Fungicidal 3-(N-acyl or thioacyl- N-arylamino)-gamma-butyrolactones and butyrothiolactones - Google Patents

Abstract

Compounds having fungicidal activity, especially against plant fungal infections caused by Phytophthora infestans or Plasmopara viticola, are represented by the formula: <IMAGE> wherein Ar represents phenyl, naphthyl, or phenyl or naphthyl substituted by from 1 to 4 of the same or different substituents selected from fluoro, chloro, bromo, C1-4 alkyl and C1-4 alkoxy; R<1> represents C2-6 alkenyl, C2-6 alkenyl oxide, C2-6 alkenyl substituted by halogen or alkoxy of from 1 to 4 carbon atoms, C3-6 cycloalkyl, or C3-6 cycloalkyl substituted by from 1 to 4 of the same or different substituents selected from C1-4 alkyl, fluoro, chloro, bromo, hydroxy and C1-4 alkoxy; R<2> represents hydrogen, chloro, bromo, C1-6 alkyl, phenyl or phenyl substituted by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo and C1-6 alkyl; Y is O, S or -NR- wherein R is hydrogen or C1-4 alkyl; W is O or S; and X is O or S, with the proviso that when W is S, R<1> can also represent hydroxymethyl, halomethyl of from 1 to 3 of the same or different halogens selected from fluoro, chloro and bromo, C2-6 alkoxyalkyl, C2-5 alkylthioalkyl, C7-10 phenylthioalkyl, C7-10 phenoxyalkyl, C7-10 phenylthioalkyl or phenoxyalkyl substituted on the phenyl ring by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo, C1-4 alkyl and C1-4 alkoxy; and with the further proviso that when Ar is phenyl or substituted phenyl, W is O and R<1> is cyclopropyl, then Y is not O.

Description

SPECIFICATION Fungicidal 3-(N-acyl or thioacyl-N-arylamino)-gamma-butyrolactones and butyrothiolactones This invention relates to 3-(N-acyl-N-arylamino)- and 3-(N-thioacyl-N-arylamino)-gamma-butyrolactones and -butyrothiolactones having fungicidal activity.

It has been found that certain 3-(N-acyl-N-arylmino)- and 3-(N-thionoacyl-N-arylamino)-gammabutyrolactones and -butyrothiolactones ar effective for the control of fungi, especially for downy mildew fungal infection caused by fungal species of the Peronosporaceae family and late blight fungal infection caused by Phytophthora infestans. Novel fungicidal compounds have been found wherein the N-acyl group is alkenyl carbonyl or alkenyl oxide carbonyl, or cycloalkyl carbonyl. Novel fungicidal N-thionoacyl compounds have also been found. Some of the compounds of the invention are effective both as protectant fungicides, i.e. they prevent or protect against fungal infections, and as eradicant fungicides, i.e. they eliminate and cure established infections. The compounds of the invention are especially preferred for the control of grape downy mildew.

In its broadest aspect the invention is concerned with compounds represented by the general formula:

wherein Ar represents phenyl, naphthyl, or phenyl or naphthyl substituted by from 1 to 4 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms; R' represents alkenyl of from 2 to 6 carbon atoms, alkenyl oxide of from 2 to 6 carbon atoms, alkenyl of from 2 to 6 carbon atoms substituted by halogen or alkoxy of from 1 to 4 carbon atoms, cycloalkyl of from 3 to 6 carbon atoms, or cycloalkyl of from 3 to 6 carbon atoms substituted by from 1 to 4 of the same or different substituents selected from alkyl of from 1 to 4 carbon atoms, fluoro, chloro, bromo, hydroxy and alkoxy of from 1 to 4 carbon atoms;R2 represents hydrogen, chloro, bromo, alkyl of from 1 to 6 carbon atoms, phenyl or phenyl substituted by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo and alkyl of from 1 to 6 carbon atoms; Y is O, S or -NR- wherein R is hydrogen or alkyl of from 1 to 4 carbon atoms;W is O or S; and X is O or S, with the proviso that when W is S, R' can also represent hydroxymethyl, halomethyl of from 1 to 3 of the same or different halogens selected from fluoro, chloro and bromo, alkoxyalkyl of from 2 to 6 carbon atoms, alkylthioalkyl of from 2 to 6 carbon atoms, phenylthioalkyl of from 7 to 10 carbon atoms, phenoxyalkyl of from 7 to 10 carbon atoms, phenylthioalkyl or phenoxyalkyl of from 7 to 10 carbon atoms substituted on the phenyl ring by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms; and with the further proviso that when Ar is phenyl or substituted phenyl, W is 0 and R' is cyclopropyl, then Y is not 0.

Representative substituted-phenyl groups which Ar may represent are 2-fluorophenyl, 2,4dichlorophenyl, 3,5-dibromophenyl, 4-methylphenyl, 2,6-diethylphenyl, 4-methoxyphenyl, 4nitrophenyl, 2,6-dimethyl-4-chlornphenyl, 2,3,6-trimethylphenyl, 2,3, 5,6-tetramethylphenyl.

Preferred substituted-phenyl Ar groups are phenyl substituted with 1 to 2 of the same or different substituents selected from chloro, bromo, alkyl or 1 to 4 carbon atoms or alkoxy 1 to 4 carbon atoms. Most preferred substituted-phenyl Ar groups are 2,6-dialkylphenyl, especially 2,6dimethylphenyl.

Representative substituted-naphthyl Ar groups are 1-naphthyl, 2-naphthyl, 1-methyl-2-naphthyl, 4-methyl-2-naphthyl, 4-methyl- 1 -naphthyl, 2-chloro- 1 -naphthyl, 2-methoxy- 1 -naphthyl, 2, 7-dimethyl-1 -naphthyl. Preferred substituted naphthyl Ar groups are 2-alkyl- 1 -naphthyl groups, especially 2-methyl-1 -naphthyl.

Representative halomethyl groups which R' may represent include fluoromethyl, chloromethyl, bromomethyl, dichloromethyl, tribromomethyl and fluorodichloromethyl. The preferred halome thyl R' group is chloromethyl.

Representative cycloalkyl R' groups are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and 4-methylcyclohexyl.

Representative alkoxyalkyl R' groups are methoxymethyl, ethoxymethyl, isopropoxymethyl and n-pentoxymethyl. The preferred alkoxyalkyl R' group is methoxymethyl.

Representative alkylthioalkyl R1 groups are methylthiomethyl, n-propylthiomethyl and npentylthiomethyl.

Representative cycloalkyl of R' groups are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and 4-methylcyclohexyl.

Representative substituted-phenylthioalkyl and substituted-phenoxyalkyl R' groups are $ chlorophenylthiomethyl, 4-methylphenoxymethyl, 2,4-dichlorophenoxymethyl, 3,5-dimethylphenylthiomethyl and 2-chloro-4-methylphenoxymethyl.

Representative alkenyl R' groups are vinyl, 2-methylvinyl, 2,2-dimethylvinyl, 1-methylvinyl, allyl, isopropenyl, butenyl, 3-methoxyprop-1-en-1-yl, 3-chloro-prop-1-en-1-yl. The preferred alkenyl groups are vinyl, 2-methylvinyl and 2,2-dimethylvinyl.

Representative R' alkenyl oxide groups are oximnyl, 1 -methyloxiran- 1 -yl, 2,2-dimethyloxiran1-yl, 2-methyloxiran-1 -yl.

Representative alkyl R2 groups are methyl, ethyl, isopropyl and n-hexyl. Representative substituted-phenyl R2 groups are 2-chlorophenyl, 2,4-dichlorophenyl, 4-methylphenyl and 2,3dimethylphenyl.

Preferably Ar is phenyl substituted with 1 to 2 of the same or different substituents selected from fluoro, chloro, bromo or alkyl of 1 to 2 carbon atoms, or 2-alkyl-1-naphthyl. The most preferred Ar groups are 2,6-dimethylphenyl or 2-methyl-1-naphthyl.

Preferably R' is vinyl, 2-methylvinyl, 2,2-dimethylvinyl, alkoxymethyl of 1 to 6 carbon atoms, chloromethyl or bromomethyl. Most preferably R' is vinyl, allyl, 2-methyl-vinyl, 1,2-epoxypropyl, methoxymethyl or chloromethyl.

When R' is cycloalkyl or 3 to 6 carbon atoms, then preferably R' is cyclopropyl when Y= S and cyclopentyl when Y = 0.

Representative X and W are both oxygen. When W is sulfur, R' is preferably methoxymethyl.

Preferably R2 is hydrogen or methyl.

A preferred class of N-phenylamino- and N-substituted phenylaminolactones is that represented -by the formula (II)

wherein R' is alkenyl of 2 to 6 carbon atoms or alkenyl oxide of 2 to 6 carbon atoms, R2 is hydrogen or methyl, and R4 and R5 individually are methyl or ethyl, and Y is O or S. Particularly preferred compounds of formula (II) are those wherein R' is vinyl, 2-methylvinyl, 1,2epoxypropyl or 2,2-dimethylvinyl, R2 is hydrogen and R4 and R5 are methyl.

The 3-(N-thionoacyl-N-arylamino) lactones and thiolactones of the invention may be represented by the formula

wherein Ar is phenyl, naphthyl or substituted phenyl or naphthyl as previously defined, and R', X, Y and R2 have the same significance as previously defined. A preferred class of 3-(N thionoacyl-N-arylamino) lactones is that represented by the formula

wherein R1 is alkoxyalkyl of 2 to 6 carbon atoms, R2 is hydrogen or methyl, R4 and R5 individually are methyl or ethyl, and Y is O or S. Preferred compounds of formula (IV) are those wherein R' methoxymethyl, R2 is hydrogen, and R4 and R5 are methyl.

Representative compounds of the formula (I) are: 3-(N-acryloyl-N-2, 6-dimethylphenylamino)-gamma butyrolactone, 3-(N-3-methylcrotonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone, 3-(N-crotonyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone, 3-(N-acryloyl-N-2, 6-dimethylphenylamino)-gamma-thio-butyrolactone, 3-(N-2-methylacryloyl-N-2-methyl-6-ethylphenylamino)-gamma-butyrolactone, 3-(N-3-methyl-2, 3-epoxy-butanoyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone, 3-(N-2-methyl-2, 3-epoxy-propanoyl-N-2,6-dimethyl-phenylamino)-gamma-butyrolactone, 3-(N-methoxythionoacetyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone, 3-(N-methoxythionoacetyl-N-2, 6-dimethylphenylamino)-gamma-thiobutyrolactone.

A preferred class of N-cycloalkylcarbonyl-phenylamino-thiolactones is that represented by the formula

wherein R' is cycloalkyl of 3 to 6 carbon atoms, R2 is hydrogen or methyl, and R4 and R5 individually are methyl or ethyl. A particularly preferred compound of formula (V) is that wherein R' is cyclopropyl, R2 is hydrogen and R4 and R5 are methyl.

The N-cycloalkylcarbonyl-phenylaminolactones of the invention may be represented by the formula

wherein Ar is phenyl or substituted phenyl as previously defined, R2 has the same significance as previously defined, and R' is cycloalkyl of 3 to 6 carbon atoms. A preferred class of Nphenylamino- and N-substituted-phenylaminolactones is that represented by the formula

wherein R' is cycloalkyl of 4 to 6 carbon atoms, R2 is hydrogen or methyl, and R4 and R5 individually are methyl or ethyl. A preferred compound of formula (VII) is that wherein R' is cyclopentyl, R2 is hydrogen, and R4 and R5 are methyl.

The N-cycloalkylcarbonyl-phenyl (and naphthyl) aminolactones and thiolactones of the invention may be represented by the formula

wherein Ar is phenyl or naphthyl or substituted phenyl or naphthyl, and wherein R', R2 and Y have the same significance as previously defined. A preferred class of N-naphthyl-aminolactones and thiolactones is that represented by the formula (lX)

wherein R' is cycloalkyl or substituted cycloalkyl of 3 to 6 carbon atoms; R2 has the same significance as previously defined; R3 is hydrogen or alkyl of 1 to 3 carbon atoms; and Y is oxygen or sulfur. Particularly preferred compounds of formula (IX) are those wherein R' is cyclopropyl, R3 is methyl and Y is oxygen.

Representative compounds of formula (I) include: 3-(N-cyclobutylcarbonyl-N-phenylamino)-gamma-butyro-thiolactone; 3-(N-cyclohexylcarbonyl-N-4-chlorophenylamino)-gammabutyrothiolactone; 3-(N-cyclohexylcarbonyl-N-4-methoxyphenylamino)-gamma-butyrothiolactone; 3-(N-cyclopropylcarbonyl-N-2, 6-dimethylphenylamino)-5-methyl-gamma-butyrothiolactone; 3-(N-cyclopenylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-butyrothiolactone; 3-(N-cyclopropylcarbonyl-N-3,4-dimethylphenylamino)-gamma-butyrothiolactone; 3-(N-cyclobutylcarbonyl-N-4-methylphenylamino)-5-chloro-gamma-butyrothiolactone; 3-(N-cyclopropylcarbonyl-N-2-methoxyphenylamino)-gamma-butyrolactone; 3-(N-cyclohexylcarbonyl-N-2-methylnaphth 1 -ylamino)-5-phenyl-gamma-butyrothiolactone;; 3-(N-cyclobutylcarbonyl-N-2-methylnaphth-1 -ylamino)-gamma-butyrothiolactone; 3-(N-(2-chlorocyclopropylcarbonyl-N-2-methyinaphth-1-ylamino)-gamma-butyrolactone and 3-(N-(2-methylcyclopropylcarbonyl)-N-2-methylnaphth- 1 -ylamino)-gamma-butyrolactone; 3-(N-cyclopropylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-butyrothiolactone.

The lactone and thiolactone compounds of the invention may be prepared by alkylating an aniline (X) with an alpha-halo-gamma-butyrolactone or alpha-halo-gamma-thiobutyrolactone (XI) and subsequently acylating the alpha-(N-arylamino)-gamma-butyrolactone or thiobutyrolactone (XII) with an acyl halide (XIII) to give the 3-(N-acyl-N-arylamino)-gamma-butyrolactone or thiobutyrolactone product (IA), as depicted by the following equations:

wherein Ar, R', R2 and Y have the same significance as previously defined, and X is chloro or bromo.

The alkylation reaction (1) is conducted in the presence of a base. Suitable bases are inorganic alkali metal carbonates such as sodium carbonates or potassium carbonate or organic amines such as trialkylamines, e.g., triethylamine, or pyridine compounds, e.g., pyridine or 2,6dimethylpyridine. Generally, substantially equimolar amounts of reactants (X) and (XI) and the base are employed. In one modification of the reaction, a molar excess of the aniline reactant (X) is used as the base, and no additional base is employed.The reaction is conducted in inert organic solvents, e.g., apolar diprotic solvents such as dimethylformamide and acetonitrile and aromatic hydrocarbons such as benzene and toluene, at reaction temperatures varying from 25"C to 1 50'C, preferably from 50"C to 1 50 C. Water may be employed as a co-solvent. The reaction pressure may be atmospheric, subatmospheric or superatmospheric. However, for convenience of conducting the reaction, the pressure is generally atmospheric. The reaction time will, of course, vary depending upon the reactants and the reaction temperature. Generally the reaction time is from 0.25 to 24 hours. The product (XII) as generally purified by conventional procedures, e.g., extraction, distillation or crystallization, before use in the acylation reaction (2).

The acylation reaction (2) is conducted by conventional procedures. The reactants (Xll) and (XIII) are generally contacted in substantially equimolar amounts in an inert organic solvent at a temperature of 0, to 1 00 C. Suitable inert organic solvents include ethyl acetate, methylene dichloride, dimethoxyethane, benzene, etc. The product is isolated and purified by conventional procedures such as extraction, distillation, chromatography, crystallization, etc.

When preparing a butyrolactone product (compounds of formula (I) wherein W, X and Y = 0), an organic amine such as a trialkylamine or a pyridine compound may be employed as an acid acceptor. However, when preparing a butyrothiolactone product (compounds of formula (I) wherein W and X = 0 and Y = S), an organic amine should not be employed.

The compounds of formula (IA) wherein R' is alkylthioalkyl, phenylthioalkyl or substitutedphenylthioalkyl may be prepared from the corresponding compound wherein R' is haloalkyl by reacting the corresponding haloalkyl compound with an alkali metal mercaptide by conventional procedures as depicted in the following equation (3) in the case where R' is alkylthiomethyl:

wherein Ar, R2, X and Y are as previously defined, M is alkali metal, R is alkyl, phenyl or substituted phenyl. In reaction (3), Y preferably is oxygen.

The compounds of Formula (IA) wherein R' is hydroxymethyl and Y is oxygen may be prepared by treatment of the corresponding compound wherein R' is halomethyl with an inorganic alkali metal hydroxide, such as aqueous sodium hydroxide. The compounds of Formula (IA) wherein R' is hydroxymethyl and Y is oxygen or sulfur may be prepared by hydrolysis of the corresponding compound wherein R' is alkanoylmethyl.

Compounds of the formula (IA) wherein R' is alkenyl oxide are prepared by oxidizing the corresponding compound wherein R' is alkenyl with an oxidizing agent such as 3-chloroperbenzoic acid, in the presence of an inorganic base, such as potassium acid phosphate.

The compounds of Formula (IA) wherein R2 is chloro or bromo are generally prepared by chlorinating or brominating the corresponding compound wherein R2 is hydrogen with a chlorinating or brominating agent such as N-bromosuccinimide or N-chlorosuccinimide by conventional procedures, as depicted in the following equation (4):

wherein Ar, R', Y and X are as previously defined.

The 3-(N-thionoacyl-N-arylamino) butyrolactones and thiobutyrolactones are prepared from the corresponding 3-(N-acyl-N-arylamino) butyrolactones and thiobutyrolactones of the formula (II) according to the following scheme:

The reaction (5) is carried out at the reflux temperature of the solvent, preferably xylene, with molar ratio of (IIA) to phosphorous pentasulfide of about 4:1, in the presence of a trace of a base, such as pyridine. The product (XIV) may be isolated by conventional chromatography.

The thiolactone compounds of the invention may be prepared by cleaving the corresponding lactone (I) with an alkyl mercaptide salt followed by formation of the thiolactone employing a halogenating agent such as phosphorus trichloride, phosphorus pentachloride, thionyl chloride or oxalyl chloride, as depicted by the following equations:

wherein R', R2 and Ar are as previously defined.

UTILITY The compounds of the invention are useful for controlling fungi, particularly plant fungal infections. However, some fungicidal compositions of the invention may be more fungicidally active than others against particular fungi. For example, the activity of the preferred compounds of the invention is highly specific for certain fungal diseases such as downy mildews, e.g., Plasmopara viticola (grapes) and Peronospora parasitica (cabbage and collard), late blights, e.g., Phytophthora infestans tomatoes and potatoes), and crown and root rots, e.g., Phytophthora.

The compounds of the invention are particularly useful fungicides because they cure established fungal infections. This permits economical use of the fungicides of the invention, because they need not be applied to plants unless fungal infection actually occurs. Thus, a preventative program of applying fungicides against potential fungal infection is not necessary.

When used as fungicides, the compounds of the invention are applied in fungicidally effective amounts to fungi and/or their habitats, such as vegetative hosts and nonvegetative hosts, e.g., animal products. The amount used will, of course, depend on several factors such as the host, the type of fungus and the particular compound of the invention. As with most pesticidal compounds, the fungicides of the invention are not usually applied full strength, but are generally incorporated with conventional, biologically inert extenders or carriers normally employed for facilitating dispersion of active fungicidal compounds, recognizing that the formulation and mode of application may affect the activity of the fungicide.Thus, the fungicides of the invention may be formulated and applied as granules, as powdery dusts, as wettable powders, as emulsifiable concentrates, as solutions, or as any of several other known types of formulations, depending on the desired mode of application.

Wettable powders are in the form of finely divided particles which disperse readily in water or other dispersant. These compositions normally contain from about 5-80% fungicide, and the rest inert material, which includes dispersing agents, emulsifying agents and wetting agents.

The powder may be applied to the soil as a dry dust, or preferably as a suspension in water.

Typical carriers include fuller's earth, kaolin clays, silicas, and other highly absorbent, wettable, inorganic diluents. Typical wetting, dispersing or emulsifying agents include, for example: the aryl and alkylaryl sulfonates and their sodium salts, alkylamide sulfonates, including fatty methyl taurides; alkylaryl polyether alcohols, sulfated higher alcohols and polyvinyl alcohols; polyethylene oxides, sulfonated animal and vegetable oils; sulfonated petroleum oils, fatty acid esters of polyhydric alcohols and the ethylene oxide addition products of such esters; and the addition products of long-chain mercaptans and ethylene oxide. Many other types of useful surface-active agents are available in commerce. The surface-active agent, when used, normally comprises from 1% to 15% by weight of the fungicidal composition.

Dusts are freely flowing admixtures of the active fungicide with finely divided solids such as talc, natural clays, kieselguhr, pyrophyllite, chalk, diatomaceous earths, calcium phosphates, calcium and magnesium carbonates, sulfur, lime, flours, and other organic and inroganic solids which act as dispersants and carriers for the toxicant. These finely divided solids have an average particle size of less than about 50 microns. A typical dust formation useful herein contains 75% silica and 25% of the toxicant.

Useful liquid concentrates include the emulsifiable concentrates, which are homogeneous liquid or paste compositions which are readily dispersed in water or other dispersant, and may consist entirely of the fungicide with a liquid or solid emulsifying agent, or may also contain a liquid carrier such as xylene, heavy aromatic naphthas, isophorone, and other nonvolatile organic solvents. For application, these concentrates are dispersed in water or other liquid carrier, and are normally applied as a spray to the area to be treated.

Other useful formulations for fungicidal applications include simple solutions of the active fungicide in a dispersant in which it is completely soluble at the desired concentration, such as acetone, alkalated naphthalenes, xylene, or other organic solvents. Granular formations, wherein the fungicide is carried on relatively coarse particles, are of particular utility for aerial distribution or for penetration of cover-crop canopy. Pressurized sprays, typically aerosols wherein the active ingredient is dispersed in finally divided form as a result of vaporization of a low-boiling dispersant solvent carrier, such as the Freons, may also be used. All of those techniques for formulating and applying fungicides are well known in the art.

The percentages by weight of the fungicide may vary according to the manner in which the composition is to be applied and the particular type of formulation, but in general comprise 0.5 to 95% of the toxicant by weight of the fungicidal composition.

The fungicidal compositions may be formulated and applied with other active ingredients, including other fungicides, insecticides, nematocides, bactericides, plant growth regulators, fertilizers, etc.

Examples The preparation and fungicidal activity of the compounds of the invention is illustrated by the following examples.

Example i-Preparation of 3-(N-methoxyacetyl-N-2, 6-dimethylphenylamino)-gamma-thiobutyrolactone A solution of 1.46 g (0.0135 mol) methoxyacetylchloride in 10 ml dichloromethane was added dropwise to a refluxing solution of 3 g (0.0135 mol) 3-(N-2,6-dimethylphenylamino)gamma-thiobutyrolactone in 200 ml toluene. The reaction mixture was heated at reflux for 3 hours and evaporated to give a solid. The solid was recrystallized from a 10:1:10 solvent mixture of ether:benzene:hexane to give 1.8 g of the product, as a tan solid, m.p. 86-87"C.

The infrared spectrum of the product shows two strong carbonyl absorption bands at 5.85 microns and 6.03 microns.

Example 2-Preparation of 3-(N-acetoxyacetyl-N-2, 6-dimeth ylphen ylamin o)- gamma-b utyrola C- tone A 13.7-9 (0.1-mol) sample of acetoxyacetyl chloride was added dropwise to a solution of 20.5 g (0.1 mol) N-2,6-dimethylphenylamino-gamma-butyrolactone and 7.9 g (0.1 mol) pyridine in 1 50 ml benzene. After completion of the addition, the reaction mixture was stirred at about 25"C for 4 hours, then washed with water, dried over magnesium sulfate and evaporated under reduced pressure to give an oily residue. The residue was crystallized from ethyl ether/hexane to give 27.3 g of product, m.p. 90-91"C.

3-(N-cyclopropylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone can be made in an analogous manner using cyclopropylcarbonyl chloride and N-2, 6-dimethylphenylaminogamma-butryolactone as starting materials.

Example 3-Preparation of 3-(N-hydroxyacetyl-N-2, 6-dimethyiph enylamin o-gamma-b utyrolac- tone A solution of 50 g (0.18 mol) 3-(N-chloroacetyl-N-2,6-dimethylphenylamino)-gamma-butyro- lactone, 14.5 g (0.36 mol) sodium hydroxide dissolved in 50 ml water, and 450 ml dimethoxyethane was stirred at about 25"C for 1 6 hours. The resulting reaction mixture was filtered, diluted with 500 ml dichloromethane. Hydrogen chloride gas was bubbled into the reaction mixture for 1 hour. The reaction mixture was filtered, dried over magnesium sulfate, and evaporated under reduced pressure. The residue was washed with 10% ethyl ether/90% hexane, filtered and air-dried to give 36.5 g of the product as a white crystalline solid, m.p.

173-174"C.

Example 4 Preparation of 3-(N-ethoxyacetyl-N-2, 6-dimethylphenylamino-gamma-butyrolactone A 6.2-g (0.05-mol) sample of ethoxyacetyl chloride was added dropwise to a refluxing solution of 10.3 (0.05 mol) 3-(N-2,6-dimethylphenylamino)-gamma-butyrolactone in 1 50 ml toluene. The reaction mixture was then heated under reflux for 2 hours. After cooling, the reaction mixture was washed with water, washed with saturated sodium bicarbonate solution, washed with water, dried over magnesium sulfate and evaporated to give 11.2 g of 3-(N ethoxyacetyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone, m.p. 73-75"C.

Example 5Preparation of 3-(N-methylthioacetyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone A 22-g (0.3-mol) sample of sodium methylmercaptide was added in small portions to a solution of 25.3 g (0.08 mol) N-bromoacetyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone, m.p. 116-117"C, in 200 ml dimethylsulfoxide. A mild exotherm ensued. The reaction mixture was allowed to stir at about 25"C for about 16 hours. The reaction mixture was then heated to about 150"C under reduced water aspirator pressure to remove a portion of the dimethyl sulfoxide solvent. The residue was diluted with water and the aqueous layer separated.The organic portion was dissolved in 350 ml dichloromethane, washed with water, dried over magnesium sulfate and evaporated under reduced pressure to give an oil. The oil was chromatographed through a silica gel column (20% acetone/80% petroleum ether elution) to give the product (11 g), which after crystallization from ethyl ether/acetone melted at 77-78"C.

Example 6-Preparation of 3-(N-methoxyacetyl-N-2-methylnaphth- 1 -ylamino)-gamma-butyrolactone A 2.4-g (0.022-mol) sample of methoxyacetyl chloride was added dropwise to a solution of 5.5 g (0.022 mol) 3-(N-2-methylnaphth-1-ylamino)-gamma-butyrolactone and 1.7 g (0.022 mol) pyridine in 100 ml dichloromethane. The reaction mixture was stirred one hour at about 25"C and then heated under reflux for 6 hours. After cooling overnight, the reaction mixture was washed successively with water, saturated sodium bicarbonate solution, water, dried over magnesium sulfate and evaporated under reduced pressure. The residue was chromatographed through a silica gel column. Elution with 25% acetone/75% petroleum ether gave 4.3 g of the product, m.p. 42-46"C.

Example 7-Preparation of 3-(N-methoxythionoacetyl-N-2,6-dimethylphenylaminoJ-gamma-thio- butyrolactone A slurry of phosphorus pentasulfide (6.0 g) in 300 ml xylene was heated under a Dean Stark water separator to azetropically remove any water present.

After cooling to 100"C pyridine (2 ml) was added followed by 3-(N-methoxyacetyl-3-N-2,6dimethylphenylamino)-gamma-butyrolactone (33.3 g). The stirred slurry was heated at 150 .

After about 45 minutes, the phosphorus pentasulfide dissolved and the mixture was kept at 150 over a weekend.

The mixture was diluted with an equal volume of methylene chloride and washed with saturated sodium bicarbonate (200 ml), water (200 ml) and dried (MgSO4).

The solution was filtered and the filtrate was stripped in vacuo to yield a dark oil which was chromatographed on silica gel (300 g) by elution with petroleum ether, 80% petroleum ether in ethyl ether, 70% petroleum ether in ethyl ether, 60% petroleum ether in ethyl ether, 40% petroleum ether in ethyl ether and 25% petroleum ether in ethyl ether.

The oil isolated from the petroleum ether: ethyl ether elutions were dissolved in methylene chloride and treated with charcoal and MgSO4, filtered and stripped to yield the title product as an oil (1.8 g). The product is reported as compound 10 in Table B.

Example 8-Preparation of 3-(N-crotonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone Crotonic acid (6 g) and thionyl chloride (12 g) were refluxed for one hour and the excess thionyl chloride was removed in vacuo. 3-(N-2,6-dimethylphenylamino)-gamma-butyrolactone (14 g) was added with 150 ml toluene and refluxed for 2 hours.

The mixture was washed with water, saturated sodium bicarbonate, dried (MgSO4), filtered and stripped of solvent. The product was chromatographed on 260 g silica gel; elution with acetone/ether/petroleum ether to yield 3.1 g of the title product, m.p. 122-123"C. The product is reported as compound 3 in Table A.

Example 9-Preparation of 3-(N-3-methyl-2, 3-epoxy-butanoyl-N-2, 6-dimethylphenylamino)- gamma-butyrolactone 3-(N-3-methyl-crotonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone (A) was prepared as in Example 8 using 3-methyl-crotonic acid as a starting material. Product A (9 g), 3-chloroperbenzoic acid (6 g) and KH2PO4 (4.7 g) in 75 ml dichloromethane were refluxed for 48 hours.

The mixture was washed with water, dried (MgSO4), stripped. The residue was crystallized in ether/hexane to yield 5.4 g of the title product, m.p. 100-104"C. The product is reported as Compound 7 in Table A.

Example I 0-Mycelial Inhibition Compound 2 of the present invention was evaluated for fungicidal effectiveness by means of a mycelial inhibition test. This test is designed to measure the fungitoxic activity of fungicidal chemicals in terms of their degree of inhibition of mycelium growth. Compound 2 was dissolved in acetone to 500 ppm concentration. Paper strips were inoculated with Pythium ultimum mycelium growth by covering the paper with a potato dextrose broth culture of mycelial suspension. The inoculated papers were then placed on potato dextrose agar plates and sprayed by means of a micro sprayer with the fungicidal solution. The treated paper strips were incubated at 25"C and data is taken after 24 hours. Fungicidal activities are measured by a zone of inhibited mycelial growth from the center of the paper strip.The effectiveness of Compound 2 tested for fungicidal activity is 100% in terms of percent inhibition relative to Difolatan.

Example 1 li-Tomato Late Blight Compounds of the invention were tested for the preventative control of the Tomato Late Blight organism Phytophthora infestans. Five- to six-week-old tomato (cultivar Bonny Best) seedlings were used. The tomato plants were sprayed with a 250-ppm suspension of the test compound in acetone, water and a small amount of a nonionic emulsifier. The sprayed plants were then inoculated one day later with the organism, placed in an environmental chamber and incubated at 66-68"F and 100% relative humidity for at least 16 hours. Following the incubation, the plates were maintained in a greenhouse at 60-80% relative humidity for approximately 7 days.

The percent disease control provided by a given test compound was based on the percent disease reduction relative to untreated check plants. The results are tabulated in Tables I and II.

In the Tables, the test concentration is 250 ppm unless otherwise indicated by the figures in parentheses.

Example 12-Celery Late Blight The celery late blight tests were conducted using celery (Utah) plants 11 weeks old. The celery late blight organism was Septoria apii. The celery plants were sprayed with solutions of the candidate toxicant mixed with acetone, water and a nonionic emulsifier. The plants were then inoculated with the organism and placed in an environmental chamber and incubated at 66-68"F in 100% relative humidity for an extended period of time (approximately 48 hours).

Following the incubation the plants were allowed to dry and then were maintained at a 60-80% relative humidity for approximately 14 days. The percent disease control provided by a given candidate toxicant is based on the percent disease reduction relative to untreated check plates.

The results are reported in Tables I and II.

Example 13-Grape Downy Mildew Control The compounds of the invention were tested for the control of the grape downy mildew organism Plasmopara viticola.

Detached leaves, between 70 and 85 mm in diameter, of 7-week-old Vitis vinifera cultivar Emperor grape seedlings were used as hosts. The leaves were sprayed with a solution of the test compound in acetone. The sprayed leaves were dried, inoculated with a spore suspension of the organism, placed in a humid environmental chamber and incubated at 18-22 C and about 100% relative humidity. Seven to nine days after inoculation, the amount of disease control was determined. The percent disease control provided by a given test compound was based on the percent disease reduction relative to untreated check plants. The results are tabulated in Tables I and II.

Example 14 Tomato Early Blight Compounds of the invention were tested for the control of the Tomato Early Blight organism, Alternaria solani conidia. Tomato (variety Bonny Best) seedlings of 6 to 7 weeks old were used.

The tomato plants were sprayed with a 250-ppm solution of the test compound in an acetoneand-water solution containing a small amount of a nonionic emulsifier. The sprayed plants were inoculated one day later with the organism, dried and maintained at 60-80% relative humidity for about 1 2 days. Percent disease control was based on the percent disease development on untreated check plants. The compounds tested and the results are tabulated in Table I and II.

Example 15-Powdery Mildew The powdery mildew test was made using bean seedlings (var. Bountiful) with well-developed primary leaves. The pathogen was Erysiphe polygoni. The bean seedlings were sprayed with a 250-ppm solution of the test compound in an acetone-water mixture containing a nonionic emulsifier. The treated plants were inoculated one day after spray application of the test compound with the pathogen. The plants were then maintained in a greenhouse at a 60-80% relative humidity and at a temperature of 68-70"F. The rate of infection on the leaves was made after about 10 days. The percent disease control provided by a given test compound was based on the disease reduction relative to untreated check plants. The results are reported in Table II.

Example 16-Leaf Rust The leaf-rust was made using pinto beans. The pathogen was Uronyces phaseoli tipica. The pinto-bean plants were sprayed with a 250-ppm solution of the test compound in an acetonewater mixture containing a nonionic emulsifier. The treated plants were inoculated thereafter with the pathogen and then incubated in an environmental chamber for approximately 20 hours at 100% relative humidity and a temperature of 68-70"F. The plants were then removed from the chamber, allowed to dry, and then maintained in a greenhouse at a 60-80% relative humidity. The rate of infection on the leaves was made after about 14 days. The percent disease control provided by a given test compound was based on the disease reduction relative to untreated check plants. The results are reported in Table II.

Example ? 17-Preparation of 3-(N-cyclopentylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-bu- tyrolactone A 5.7 g. (.043 mol) sample of cyclopentylcarbonyl chloride was added dropwise to a solution of 8.8 g. (.043 mol) N-2,6-dimethylphenylamino-gamma-butyrolactone in 100 ml toluene. After completion of the addition, the reaction mixture was refluxed overnight, then washed with water, saturated sodium carbonate solution and again with water, dried over magnesium sulfate and evaporated under reduced pressure to give an oil residue. The residue was crystallized from ethyl ether to give 6.1 g of product, m.p. 109-1 13'C. This product is tabulated in Table C as Compound No. Cl.

Example 18-Preparation of 2-(N-cyclopropylcarbonyl-2, 6-dimethylanilin o)-4-(t-butylthio)-b uta- noic acid To 4.2 g. t-butylmercaptan in 100 ml 1,2-dimethoxy ethane was added 2.5 g. sodium methoxide with stirring.

A sample of 3-(cyclopropylcarbonyl-2,6-dimethylanilino)-butryolactone (11.6 g., made as in Example 1) was added to the reaction mixture and stirred at room temperature overnight and poured into ice water.

The mixture was washed with 2 X 100 ml toluene and the toluene was backwashed with water. The aqueous phase was acidified (pH 1) with 1 2N HCI, then extracted twice with methylene chloride. The methylene chloride extracts were washed with water, dried (MgSO4), filtered and stripped to yield the title product, 10.6 g. (oil).

Example 19-Preparation of 3-(N-cyclopropylcarbonyl 2,6-dimethylanilino)-butyrothiolactone The acid produced in Example 18 (10.6 g.) was dissolved in 200 ml methylene chloride in a flask equipped with a condensor, cooled to - 20"C then PCl3 (6.0 g.) was added dropwise. The exothermic reaction caused the mixture to warm to 36"C. More methylene chloride was added and the mixture was allowed to stand overnight at room temperature, whereupon two phases formed.

The methylene chloride layer was collected, dried (Mg SO4, Silica gel), filtered and stripped.

The resultant oil was crystallized in petroleum ether to yield the title product, m.p. 145-147"C.

The compounds tabulated in Table C were prepared by procedures similar to those of Examples 17-19. The structure of each compound tabulated in the Tables was confirmed by nuclear magnetic resonance spectroscopy and/or infrared spectral analysis.

TABLE A Compounds of the Formula

Analysis mp C H N No. A Y R C Calc Fd Calc Fd Calc Fd 1 2,6-(CH3)2# O CH = CH2 142-3 69.48 68.7 6.61 6.77 5.40 5.42 2 " O CH = C(CH3)2 86-7 71.06 71.39 7.37 7.67 4.88 4.96 3 " O CH = CHCH3 122-3 70.31 69.38 7.01 6.99 5.12 5.16 4 " S CH = CH2 101-2 65.43 62.56 6.22 6.23 5.09 4.93 5 " O C(CH3)2 = CH2 115-23 70.31 68.5 7.01 6.99 5.12 5.17 6 " S CH = C(CH3)2 123-4 67.29 68.25 6.98 7.2 4.62 4.86 7 " O # 100-04 67.31 67.44 6.98 7.6 4.62 4.66 8 " O # 109-10 66.42 68.3 6.62 7.05 4.84 5.02 11 " O # 117-18 66.42 66.15 6.62 6.72 4.84 4.76 12 2,6-CH3)2# S CH = CHCH3 117-122 66.4 68.17 6.62 6.98 4.84 5.0 13 " S CH2CH = CH2 67-69 66.4 67.0 6.62 7.08 4.84 4.89 14 " O CH2CH = CH2 84-87 70.31 70.65 7.01 7.42 5.13 5.26 15 2-methyl- O CH = CHCH3 166-172 73.77 72.13 6.19 6.36 4.53 4.45 naphth-1-yl (rotamer A) 16 " O CH = CHCH3 104-11 73.77 74.53 6.19 6.65 4.53 4.92 (rotamer B) 17 " (rotamer A) O CH = CH2 158-176 73.2 73.35 5.80 5.79 4.74 4.43 18 " (rotamer B) O CH = CH2 177-179 73.2 71.32 5.80 5.92 4.74 4.53 TABLE B Compounds of the Formula

Analysis mp C H N No.Ar Y R C Calc Fd Calc Fd Calc Fd 9 2,6-(CH3)2# O CH2OCH3 85-6 61.41 66.17 6.53 6.82 4.77 5.35 10 " S " Oil 58.22 57.35 6.19 6.11 4.53 4.55 TABLE I % Control Grape Downy Tomato Late Celery Late Tomato Early No. Mildew Blight Blight Blight 1 89 0 65 7 2 54 0 23 0 3 100 100 33 29 4 100 57 94 29 5 18 23 23 18 6 54 13 57 8 7 - 14 11 11 8 - 0 50 11 9 100 98 37 0 10 100 99 50 11 100 71 23 0 12 100 84 36 0 13 100 96 44 0 14 100 96 44 0 15 100 89 11 0 16 100 84 37 0 17 100 37 - 0 18 83 0 - 0 TABLE C Compounds of the Formula

Analysis mp C H N No. Ar R Y C Calc Fd Calc Fd Calc Fd C1 2,6-(CH3)2# # O 109-113 71.73 72.78 7.69 7.94 4.65 4.67 C2 2,6-(CH3)2# # O 119-120 71.06 70.87 7.37 7.54 4.88 4.75 C3 2,6-(CH3)2# # O 162-163 72.35 73.37 7.98 8.36 4.44 4.48 C4 2,6-(CH3)2# # S 145-147 66.40 66.97 6.62 6.75 4.84 5.4 C5A* # # O 186-190 73.7 73.79 6.19 6.43 4.53 4.47 C5B* # # O 139-142 73.77 74.35 6.19 6.29 4.53 4.49 C6 2,6-(CH3)2# # NCH3 113-114 71.30 70.35 7.74 7.74 9.78 9.69 * A and B rotamers.

TABLE II FUNGICIDAL EFFICACY No. GDM TLB CLB TEB BR BPM C1 - 81 19 0 0 10 C2 - 50 19 0 0 0 C3 - 0 7 0 0 4 C4 98 71 19 0 29 4 C5A 99 6 44 21 0 0 C5B 99 13 44 56 0 23 C6 13 11 0 0 0 98 GDM = Grape Downy Mildew TLB = Tomato Late Blight CLB = Celery Late Blight TEB = Tomato Early Blight BR = Bean Rust BPM = Bean Powdery Mildew

Claims (28)

1. Compounds represented by the general formula:

wherein Ar represents phenyl, naphthyl, or phenyl or naphthyl substituted by from 1 to 4 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms; R' represents alkenyl of from 2 to 6 carbon atoms, alkenyl oxide of from 2 to 6 carbon atoms, alkenyl of from 2 to 6 carbon atoms substituted by halogen or alkoxy of from 1 to 4 carbon atoms, cycloalkyl of from 3 to 6 carbon atoms, or cycloalkyl of from 3 to 6 carbon atoms substituted by from 1 to 4 of the same or different substituents selected from alkyl of from 1 to 4 carbon atoms, fluoro, chloro, bromo, hydroxy and alkoxy of from 1 to 4 carbon atoms;R2 represents hydrogen, chloro, bromo, alkyl of from 1 to 6 carbon atoms, phenyl or phenyl substituted by 1 or 2 of the same or different.

substituents selected from fluoro, chloro, bromo and alkyl of from 1 to 6 carbon atoms; Y is 0, S or -NR- wherein R is hydrogen or alkyl of from 1 to 4 carbon atoms: W is O or S; and X is O or S, with the proviso that when W is S, R' can also represent hydroxymethyl, halomethyl of from 1 to 3 of the same or different halogens selected from fluoro, chloro and bromo, alkoxyalkyl of from 2 to 6 carbon atoms, alkylthioalkyl of from 2 to 6 carbon atoms, phenylthioalkyl of from 7 to 10 carbon atoms, phenoxyalkyl of from 7 to 10 carbon atoms, phenylthioalkyl or phenoxyalkyl of from 7 to 10 carbon atoms substituted on the phenyl ring by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms; and with the further proviso that when Ar is phenyl or substituted phenyl, W is 0 and R' is cyclopropyl, then Y is not 0.

2. Compounds represented by the general formula:

wherein Ar represents phenyl, naphthyl, or phenyl or naphthyl substituted by from 1 to 4 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms;R' represents hydroxymethyl, halomethyl of from 1 to 3 of the same or different halogens selected from fluoro, chloro and bromo, alkoxyalkyl of from 2 to 6 carbon atoms, alkylthioalkyl of from 2 to 6 carbon atoms, phenylthioalkyl of from 7 to 10 carbon atoms, phenoxyalkyl of from 7 to 10 carbon atoms, phenylthioalkyl or phenoxyalkyl of from 7 to 10 carbon atoms substituted on the phenyl ring by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms, alkenyl of from 2 to 6 carbon atoms optionally substituted by halogen of alkoxy of from 1 to 4 carbon atoms, alkenyl oxide of from 2 to 6 carbon atoms, or cycloalkyl of from 3 to 6 carbon atoms, or cycloalkyl of from 3 to 6 carbon atoms substituted by from 1 to 4 of the same or different substituents selected from alkyl of from 1 to 4 carbon atoms, fluoro, chloro, bromo, hydroxy and alkoxy of from 1 to 4 carbon atoms; and R2 represents hydrogen, chloro, bromo, alkyl of from 1 to 6 carbon atoms, phenyl or phenyl substituted by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo and alkyl of from 1 to 6 carbon atoms; Y is 0, S or -NR- wherein R is hydrogen or alkyl of from 1 to 4 carbon atoms; and X is O or S.

3. Compounds as claimed in Claim 1 or 2, wherein Ar is 2,6-dialkylphenyl.

4. Compounds represented by the general formula:

wherein Ar is phenyl, naphthyl, or phenyl or naphthyl substituted by from 1 to 4 of the same or different substituents selected from fluoro, chloro, bromo, alkyl of from 1 to 4 carbon atoms and alkoxy of from 1 to 4 carbon atoms; R1 is cycloalkyl of from 3 to 6 carbon atoms, or cycloalkyl of from 3 to 6 carbon atoms substituted by from 1 to 4 of the same or different substituents selected from alkyl of from 1 to 4 carbon atoms, fluoro, chloro, bromo, hydroxy and alkoxy of from 1 to 4 carbon atoms; and R2 is hydrogen, chloro, bromo, alkyl of from 1 to 6 carbon atoms, phenyl or phenyl substituted by 1 or 2 of the same or different substituents selected from fluoro, chloro, bromo and alkyl of from 1 to 6 carbon atoms; and Y is 0, S or NR where R is hydrogen or alkyl of from 1 to 4 carbon atoms, with the proviso that when Ar is phenyl or substituted phenyl and R' is cyclopropyl, Y is not 0.

5. Compounds represented by the general formula:

wherein R' is alkenyl of from 2 to 6 carbon atoms or alkenyl oxide of from 2 to 6 carbon atoms, R2 is hydrogen or methyl, R4 and R5 individually are methyl or ethyl, and Y is O or S.

6. Compounds as claimed in Claim 5, wherin R' is vinyl, 2-methylvinyl, 1,2-epoxypropyl or 2,2-dimethylvinyl, R2 is hydrogen and R4 and R5 are both methyl.

7. Compounds represented by the general formula:

wherein R' is alkoxyalkyl of from 2 to 6 carbon atoms, R2 is hydrogen or methyl, R4 and R5 individually are methyl or ethyl, and Y is O or S.

8. Compounds as claimed in Claim 7, wherein R' is methoxymethyl, R2 ia hydrogen, and R4 and R5 are methyl.

9. Compounds represented by the general formula.

wherein R' is cycloalkyl of from 3 to 6 carbon atoms, R2 is hydrogen or methyl, and R4 and R5 individually are methyl or ethyl.

10. Compounds represented by the general formula:

wherein Ar is phenyl or substituted phenyl as defined in Claim 4, and R' and R2 have the same meanings as in Claim 4.

11. Compounds represented by the general formula:

wherein R' is cycloalkyl of from 4 to 6 carbon atoms, R2 is hydrogen or methyl, and R4 and R5 individually are methyl or ethyl.

1 2. Compounds represented by the general formula:

wherein R' and R2 have the same meanings as in Claim 4; R3 is hydrogen or alkyl of from 1 to 3 carbon atoms; and Y is oxygen or sulfur.

1 3. Compounds as claimed in Claim 12, wherein R' is cyclopropyl, R3 is methyl and Y is 0.

14. 3-(N-Crotonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone.

1 5. 3-(N-Acryloyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone.

1 6. 3-(N-Methylcrotonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone.

1 7. 3-(N-Acryloyl-N-2, 6-dimethylphenylamino)-gamma-thiobutyrolactone.

1 8. 3-(N-2-Methyl-2, 3-epoxy-propanoyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone.

1 9. 3-(N-Methoxythionoacetyl-N-2,6-dimethylphenylamino)-gamma-butyrolactone.

20. 3-(N-Methoxythionoacetyl-N-2, 6-dimethylphenylamino)-gamma-thiobutyrolactone.

21. 3-(N-Cyclopropylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-butyrothiolactone.

22. 3-(N-Cyclopentylcarbonyl-N-2, 6-dimethylphenylamino)-gamma-butyrolactone.

23. 3-(N-Cyclopropylcarbonyl-N-2-methylnaphth- 1 -ylamino)-gamma butyrolactone.

24. A method for the control of fungal infections, which comprises contacting the infected area with a fungicidally effective amount of a compound as claimed in any preceding claim.

25. A method according to Claim 24, wherein the fungal infection is caused by Phytophthora infestans fungus.

26. A method according to Claim 24, wherein the fungal infection is caused by Plasmopara viticola fungus.

27. A fungicidal composition comprising a biologically inert carrier and a fungicidally effective amount of a compound as claimed in any one of Claims 1 to 23.

28. Process for preparing a compound of the formula defined in Claim 1, substantially as described in any one of the foregoing Examples 1 to 9, 1 7 and 19