US3845082A - Phenylsulphoxyl-or phenylsulphonyl-rhodanides - Google Patents

Abstract

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE SUBSTITUTED ALKYLENERHODANIDES OF THE FORMULAE

2,4,5-TRI(CL-)-PHENYL-SO2-CH2-S-CN

2,3,4,5,6-PENTA(CL-)-PHENYL-SO2-CH2-S-CN

2,5-DI(CL-)-PHENYL-SO2-CH2-S-CN

4-(H3C-)-PHENYL-SO2-CH2-S-CN

2-(CL-),5-(F3C-)-PHENYL-SO2-CH2-S-CN

2-(H3C-),4,5-DI(CL-)-PHENYL-SO2-CH2-S-CN

2,4-DI(CL-),3-(NC-)-PHENYL-SO2-CH2-S-CN

2,5-DI(CL-),4-(O2N-)-PHENYL-SO2-CH2-S-CN

H3C-O-(1,4-PHENYLENE)-SO2-CH2-S-CN

O2N-(3-(O2N-)-1,4-PHENYLENE)-S(=O)-CH2-S-CN

CL-(2,6-DI(CL-)-1,4-PHENYLENE)-S(=O)-CH2-S-CN

CL-(3-(CL-)-1,4-PHENYLENE)-SO2-CH2-S-CN

Description

it?! Baifliiafiii'i m' 3,845,082 Patented Oct. 29, 1974 bon atoms inclusive, halogenated alkyl of 1 to 6 carbon 3,845,082 atoms inclusive, PHENYLSULPHOXYL- 0R PHENYLSULPHONYL- RHODANIDES ll Hendrik Dolman and Albert Tempe], van Houtenlaan,

Weesp, Netherlands, assignors to US. Philips Corporation, New York, N X.

No Drawing. Continuation of abandoned application Ser. No. 661,797, Aug. 21, 1967. This application July 27, 1970, Ser. No. 64,069

Claims priority, application Netherlands, Aug. 19, 1966,

Int. Cl. C07c 161/02 US. Cl. 260397.6 13 Claims ABSTRACT OF THE DISCLOSURE Alkylenerhodanides of the formula wherein R is substituted or unsubstituted phenyl, Alk is alkylene of 1 to 4 carbon atoms and n is 1 or 2. These compounds are useful as fungicides. Examples are 4- methoxyphenylrhodane methylsulfone, 2,4,5-trichlorophenyl-rhodane methylsulfone and 4'-nitrophenyl-2 rhodane-ethylsulfone.

This application is a continuation of Ser. No. 661,797, filed Aug. 21, 1967, now abandoned.

This invention relates to a group of phenylsulfoxyl or phenylsulfonylalkylene rhodanides useful as fungicides and to novel compounds of this group.

According to the invention the novel sulfonyl (sulfoxyl) alkylene rhodanides of the following formulae have been prepared:

wherein Alk is alkylene of 1 to 4 carbon atoms inclusive, Y is at least one member selected from the group consisting of halogen, alkyl of 1 to 6 carbon atoms, alkoXy of 1 to 6 carbon atoms inclusive, N0 CN, --CF COOH, COOR wherein R is selected from the group consisting of alkyl of 1 to 20 carbon atoms inelusive, phenyl and phenalkyl of 7-20 carbon atoms inclusive, alkylthio of 1 to 6 carbon atoms inclusive, amino, acetylamino, monoalkylamino of l to 6 carbon atoms inclusive, dialkylamino of 2 to 12 carbon atoms inclusive, halogenated alkyl of 1 to 6 carbon atoms inclusive,

and -SO -alkyleneSCN wherein the alkylene contains from 1 to 3 carbon atoms inclusive, X is a member selected from the group consisting of hydrogen, alkyl of 1 to 6 carbon atoms, alkoxy of 1 to 6 carbon atoms inelusive, N0 CN, CF COOH, COOR wherein R is selected from the group consisting of alkyl of 1 to 20 carbon atoms inclusive, phenyl and phenalkyl of 7-20 carbon atoms inclusive, alkylthio of 1 to 6 carbon atoms inclusive, amino acetylamino monoalkylamino of l to 6 carbon atoms inclusive, dialkylamino of 2 to 12 carand SO -alkyleneSCN wherein the alkylene group contains from 1 to 3 carbon atoms inclusive, V is a member having the same meaning as Y with the addition of hydrogen and with the proviso that when X is hydrogen V is other than hydrogen, m is an integer ranging from 1 to 4 inclusive and n is an integer ranging from 1 to 2 inclusive.

These novel compounds as well as the known corn-= have been found to have highly efiective fungicidal activities.

These compounds which, in general, are only very slightly phytotoxic or toxic for Warm blooded animals have been found to be effective for protecting such ob= je'ct s as plant leaf and seeds, textiles, paper pulp, paint and wood from fungus infection. In addition, in general, these compounds exhibit activity against fungi infestations of warm blooded animals particularly dermato fungus such as trichopyton rubrum.

Good results were particularly obtained by compounds of the general formula:

in which formula X is a nitro-group, one or more chlorine atoms, a methyl group, a tri-fluoromethyl group, a cyanogroup, a methoxy-group or a combination of these groups, n has the value of 1 or 2 and Alk is an alkylene group with 1 or 2 carbon atoms,

In particular reference is made to compounds of the formulae:

I Cl-S m-om-s oN I or I o1--som-s ON Cl@SCHz-S CN All these compounds 1 to inhibited the germination of spores of Fusarium culmorum, Venturia inequalz's, Phytoflhora infestans (tomato leaf), Cercospora beticola (beet leaf), Sepzoria apii (celery leaf), Plasmopara viticola (grape leaf), Botrytis cinerea (lettuce leaf) and Pericularia oryzae (rice). From the experiments it appears that the substances, for example, in the form of wettable powders are suitable for preventing fungus infections on, for example, potatoes, fruit orchids, grape vines, rice or beets.

In general the compounds of the formula:

had a very good fungicidal activity. In the first formula X designates 1 to 5 chlorine atoms, n has the value 1 or 2 and Alk is a group -CH or CH CH Excellent fungicidal activity were shown by the compounds 1, 2, 3 and 4 of the above list.

Under the prevailing test conditions the best results were obtained by:

and

Cl-Q-S o..-oH2-s CN,

in which n is 1 or 2..

' powders finely divided dispersions in water can basily be made; they can be sprayed, atomized or volatilized in a convention manner on the crop to be protected. In gen-= eral, aqueous dispersions containing 50 to 500 g. of active substance over litres of water are suitable for this purpose. For the production of a number of miscible oils, wettables and seed disinfecting compositions refer ence is made to the examples.

It may furthermore be noted that the compositions ac cording to the invention may be combined with other fungicides or pesticides such as herbicides or insecticides for widening the over-all working range of the composi= tion or for obtaining synergistic effects. For such a com= bination use may be made of triphenyl-tin-hydroxide or -acetate or tetrachloro isophthalonitrile captan.

On the basis of his knowledge of the structural formula the expert will not have difliculties in producing the compounds by methods known in the art for the production of analogous compounds. The novel compounds may be obtained in accordance with the following reaction equations:

In these formulae R and Alk have the meanings mentioned above, Me is a metal atom, for example, an alkalior alkali-earth atom such as Na, K, or Mg and Hlg is a halogen atom, preferably chlorine.

The yield of this reaction is usually better when the number of electron-accepting groups in the benzene nucleus is smaller. Satisfactory yields were obtained in the presence of one chlorine atom or one nitro group.

In this reaction equation the symbols R and Alk have the aforesaid meanings, while n has the value 1 or 2.

In general, this reaction is performed better than that indicated under A.

Suitable oxidizing agents are m-chloroperbenzoic acid and also other peracids such as perbenzoic acid or peracetic acid may be used. Moreover, KMnO K Cr O or CrO in glacial acetic acid may be employed, while furthermore good results can be obtained with air or oxygen in the presence of a catalyst, for example by passing the gas through the reaction medium. By applying a correct dose of the oxidizing agent or by a suitable choice of the reaction temperature the reaction can be terminated when the sulphoxide has been formed,

For the production of the sulphide mentioned under B use may be made of the reactions:

(0 and D) S OC12 B-SHOHzOR-S-CHzOH According to other methods than those described under A or B compounds according to the invention can be produced by reacting a compound of the formula with diazomethane.

By the experiments leading to the invention particularly the method mentioned under B has been found to be very suitable. The resultant rhodane sulphides could be separated otf without difficulty and be oxidized into the corresponding sulphones. Compounds of the general forin which formula R is a substituted or non-substituted phenyl radical, and Alk is an alkylene radical with 1 to 4 carbon atoms, are therefore important intermediate products for the production of the fungicidal compounds according to the invention. The substituted phenyl radical is preferably a phenyl group substituted by one or more substituents which may be equal or different and are chosen from the group consisting of a halogen atom, alkyl with 1 to 6 carbon atoms, NO CN, =CF COOH or such a group esterified with an aliphatic or aromatic alcohol with 1 to 20 carbon atoms, alkylthio with 1 to 6 carbon atoms, amino, acetylamino, aminomonoalkyl with 1 to 6 carbon atoms, aminodialkyl with 2 to 12 carbon atoms, halogenalkyl with 1 to 6 carbon atoms, aldehyde group, COCH and -SO alkyleneSCN, the alkylene group of which has 1 to 3 carbon atoms.

EXAMPLES 1. Production of 4-methoxyphenylrhodane methylsulphone.-19.4 g. (0.092 mol) of p-methoxybenzenesulphinic acid-potassium salt, 11.0 g. (0.102 mol) of chloromethyl-rhodanide and 200 ml. of ethanol (96%) were mixed and the mixture was refluxed for 48 hours. Then the reaction liquid was diluted with water; 4-methoxyphenyl-rhodanemethylsulfone was precipitated. The precipitate was filtered off and crystallized from 100 mls. of ethanol (96%). The yield was 10.5 g. (47%). Melting point 76 C. (Kofier).

In a similar manner the reaction constituents mentioned in the following Table I in column A and chlorometirylrhodanide were used to produce the compounds mentioned in column B according to the invention.

TABLE I l @s o.oH.s ON

I l CFa CF:

2. Production of 2,4,5-trichlorophenyl-rhodane methylsulphone.1l7 g. (0.55 mol) of 2,4,S-trichlorothiophenol were powdered with 16.5 g. (-=0.55 mol) of paraformaldehyde and ten drops of a 10% sodium methylate in methanol. The mixture was stirred for half an hour at 100 to 110 C., while nitrogen was passed through slowly; the mixture being heated at first for a few minutes at 120 C. in order to melt the substances rapidly.

Yield of 2,4,5trichlorophenylhydroxymethylsulphide 129 Melting point 6769 C.

After crystallization from petroleum-ether a melting point of 69-70.5 was attained.

7.3 g. (0.3 mol) of 2,4,S-trichlorophenyl-hyrdoxymethylsulfide were dissolved in ml. of anhydrous diethylether. At 5 to 10 C. a solution of 2.54 ml. (-=0.032 mol) of pyridine and 2.56 ml. (=0.034 mol) of thionylchloride in 40 ml. of anhydrous diethylether was added dropwise while stirring, during a period of 30 minutes, stirring being continued for minutes. The reaction mixture was then diluted with ml. of ice water, after which the ether layer was separated off. The ether solution was washed in order of succession with 150 ml. of cold 1N potassium lye and twice with 100 ml. of ice water. The solution was dried on sodium sulphate, and the solvent was distilled off. The yield of 2,4,5-trichlorophenylchloromethyl-sulphide was 5.4 g. (=86%).

Melting point .57-59.5 C. After crystallization from petroleum-ether a melting point of 595-61" C. was obtained.

13.1 g. (=0.05 mol) of 2,4,S-trichlorophenylchloromethylsulphide, and 485 g. (-=0.05 mol) of potassium rhodanide were dissolved in mls. of anhydrous acetone and the solution was refluxed for 2.5 hours. After cooling, the solution was filtered and the filtrate was inspissated to a small volume, which was diluted with water. The precipitate was filtered off, dried and crystallized from benzene.

Yield of 2,4,5-trichlorophenylrhodane methylsulphide was 9.5. g. (+66%). Melting point 117-118 C.

5.2 g. (80%) (0.03 mol) of m-chloroperbenzoic acid were added in spoonfuls while cooling (temperature 15 C.) to a solution of 2.85 g. (0.01 mol) of 2,4,5trichlorophenylrhodane methylsulphide and 50 ml. of chloroform, after 'which the mixture was boiled on a vapor bath for three hours. After the solvent had been distilled off, 30 ml. of water and 3.4 g. (0.04 mol) of sodium bicarbonate were added in order to dissolve the m-chloroperbenzoic Melting point in C.

126-128 from ethanol.

176.5-178 from methylethyl- 109-1105 from ethanol.

147-149 from isopropylether and a small amount of methanol.

111-112 from isopropanol.

acid. After half an hour the precipitate was filtered off, washed with water and dried.

Yield 3.52 g., melting point 142-145" C. (Kofier).

According to a thin layer chromatogram the crude product did not contain a sulphide or a sulphoxide (benzene: acetone 9:1). After recrystallization from ethanol the yield was 2.66 g. (84%). Melting point 146148 C. (bath) 148149 (Kofler).

In a similar manner as described in Example 3 chloro methylrhodanide was added to a solution produced by adding to a suspension of a substance of column A of Table II in acetonitrile an aqueous solution of NaOH, which mixture was boiled. The resultant sulphide (column B) was converted with metachloroperbenzoic acid into the sulphones of column C in the manner described in Example 2.

Melting point 8889 in petroleumether and a small amount of benzene Melting point 149 from isopropanol CN Cl Melting point 91-93" and a small amount of benzene Melting point 186-188 from ethanol C1 C1 G1 I l I OzNSH 0,N SCH2-SON OzNSO OH SCN Melting point 126-127 in benzene Melting point 127129 from benzene 01 31 (:1 Cl 01 0'1 Cl-@811 c1sorn-soN Cl- SOz-CH2SCN C1 Cl 21 C1 Cl O] Melting point 125-126 in isopropanol Melting point 155-156 from isopropanol -s out-sort Melting point 78 in ethanol Melting point 176.5178 from methylethylketone Melting point 70.572 petroleumether Melting point 126-128 from ethanol and a small amount of benzene 3. Production of pentaehlorophenyl-rhodane methylsulphone.-14.2 g. (=0.05 mol) of pentachlorothiophenol were suspended in 175 ml. of acetonitrile. To the suspension were added 2.0 g. of sodium hydroxide in 4.9 ml. of water. By boiling, a clear solution was obtained, to which in one batch 8.6 g. (0.08 mol) of chloromethylrhodanide were added. Boiling was continued for half an hour, after which the solvent was partly distilled off. After dilution with water the precipitate was filtered oif, washed with water, dried and crystallized from isopropanol. Yield of pentachlorophenyl-rhodane methylsulphide 10.5 g. (61% Melting point 125-126 C.

This compound was oxidized with metachloroperbenzoic acid into pentachlorophenyl-rhodane methylsulphone as described in Example 2. Melting point after crystallization from isopropanol was 155156 C.

4. Production of 2,4,S-trichlorophenyl-rhodane methylsulphoxide.--1l4 g. 0.4 mol) of 2,4,5-trichlorophenylrhodanemethylsulphide, were suspended in 1 litre of chloroform and cooled at 7 C. At this temperature g. (0.52 mol) (80%) of m-chloroperbenzoic acid (MPB) were added spoonfuls, while stirring. The temperature was kept below +10 C. by cooling. After one night (15 hours) in the refrigerator, (5 C.) a thick precipitate had been formed. This precipitate was filtered ofl, washed with chloroform and dried; yield 146 g. Melting point about C.; (mixture of m-chlorobenzoic acid and 2,4,5-trichlorophenylrhodane methylsulphoxide). The crude product was suspended in 1 litre of 0.5N sodium hydroxide, stirred and filtered off after some time. The product was then washed on the filter with 400 ml. of 1N sodium hydroxide and water. Yield of pure product after drying was 110 g. (melting point 150 (Kofier)).

9 After recrystallization from (3 litres) of ethanol, 76 g. of the substance was obtained; melting point 148-150 (bath); 153 (K.). After recrystallization from ethanol the mother liquor yielded a further 20 g. (147149,

bath; 152 (K). Yield 96 g.=80%. Similarly the 2,4-dinitrophenyl rhodane methylsulphoxide (melting point 151 C. (from ethanol)) was produced from 2,4-d1n1-trophenyl rhodane methylsulphide.

5. Production of 2,4',5'-trichlorophenyl-2-rhodaneethyl-sulphone.--13.4 gs. (0.11 mol) of 2-chloroethylrhodanide were added to a warm solution of 21.4 gs. (0.1 mol) of 2,4,S-trichlorothiophenyl, 4.0 gs. (0.1 mol) of sodium hydroxide and 150 mls. of ethanol. The reaction mixture started boiling violently and a white precipitate of sodium chloride was formed: after boiling for half an hour the pH value was 7. The solvent was evaporated by half and after the addition of 150 mls. of water a solid substance was filtered off. The crude substance melted at 65 to 70. After recrystallisation from petroleum-ether (boiling range 60-80") yield: 15.2 gs. (51%), melting point 72.5-74. a

A solution of 11.3 gs. (0.0378 mol) of 2',4',5-tr1-= chlorophenyl-2-rhodaneethylsulphide in 300 mls. of chloroform was boiled for three hours with 17.3 gs. (0.1 mol (80%) m-chloroperbenzoic acid. After termination the chloroform was completely distilled off and 200 mls. of 5% sodium bicarbonate solution in water was added to the solid residue. After standing for a few hours, during which time the suspension was occasionally stirred, the crude sulphone Was filtered off and dried (melting point 75-85). After two recrystallisations from 75 mls.

, of ethanol the yield of 2',4',5'-trichlorophenyl-2-rhodaneethylsulphone was 7.0 gs. (56%). Melting point 111- 112.

6. Production of 4'-nitrophenyl-2-rhodane-ethylsulphone.-14.6 gs. (0.12'mol) of 2-chloroethylrhodanide were added in one batch to a warm solution of 15.5 gs. (0.10 mol) of 4-nitrothiophenol in 150 mls. of ethanol, containing 4.0 gs. (0.10 mol) of sodium hydroxide. The further process was similar to that of Example 5. A yellow substance was filtered 01f; melting point 109-110 C. After recrystallisation from 50 mls. of benzene the melting point was l25-126 C. Yield of 4'-nitrophenyl-2- rhodane-ethylsulphide 13.3 gs. of yellow substance (55% To a suspension of 9.4 gs. (0.0392 mol) of 4'-nitrophenyl-2-rhodane-ethylsulphide and 300 mls. of chloroform were added in spoonfuls at about C. 20.3 gs. (0.1178 mol) (80%) of m-chloroperbenzoic acid. The reaction mixture was boiled for three hours, after which the solvent was distilled off.

The residual solid substance was stirred with 11.8 gs. (0.142 mol) of sodium bicarbonate in 200 mls. of water. After some time the precipitate was filtered off, washed with water, dried and recrystallised from 100 mls. of ethanol.

iYield of 4'-nitrophenyl-2-rhodane-ethylsulphone 7.1 gs.

" (66.6%) of yellow substance; melting point 102- 7. Production of 2,4',5' trichlorophenyl-l-rhodaneethylsulphone.1-Chloroethylrhodanide and 2,4,5-trichlorophenol were reacted in the manner described in Example 3 for producing 2,4,5'-trichlorophenyl-1- rhodane-ethylsulphide. After crystallisation from petroleum-ether this compound had a melting point of 71- parts by weight of at-taclay, 25 parts by W ig of kaolin; 7 parts by weight of sodium lignine sulphonate and 3 parts by weight of sodium oleyl N-methyltaurate. parts by Weight of each of the resultant wettables were dispersed in 100 litres of water, the dispersions obtained being sprayed in an apple orchard, on a potato field and on a sugar-beet field. Spraying was carried out at a time when the plants did practically not yet exhibit infection by fungi. The results obtained showed an inhibition of the development of Venturia inequalis, Cercospora betico-la and Phytofthora infestans.

9. Production of 2,4,5 trichlorophenyl-rhodane-methyl sulphoxide.l4.25 gs. (0.05 mol) of 2,4,5-trichloro phenyl-rhodane-methylsulphide was suspended in 100 mls.. of glacial acetic acid containing 25 mls. of 30% hydrogen peroxide. After standing at room temperature for 18 hours and after heating at 40 C. for 4 to 5 hours the basic material had been converted substantially completely, as was shown by a thin-layer chromatogram, whilst a trace of the corresponding sulphone had been formed.

After dilution with water (3 00 mls.), sucking 01f, wash= ing with water and drying the crude product had a weight of 14.65 gs. Melting point 148-149. This substance was dissolved in 150 mls. of acetone and the solution was filtered and inspissated to 60 mls. 12 gs. (80%) of pure substance crystallised out. Melting point 153 (K); 152- 154 (bath); free of sulphide and sulphone.

10. By means of the rhodanides mentioned in Example 8 miscible oils were made by dissolving 25 parts by weight of one of the rhodanides together with 5 parts by weight of a mixture (1:1) of alkylphenol-polyglycolether and. calcium dodecylbenzene sulphonate in 70 parts by weight of xylene.

Test Methods The compounds according to the invention were ex= amined by the following methods.

For the spore germination and leaf tests 31 mgs. of the substance to be tested were ground with 3 mgs. of a surface-active substance in three drops of water in a glass mill for 15 minutes and then dissolved in 10 mls. of water. On the basis of this suspension the test suspensions were prepared in the relevant concentrations by dilution with water. The suspensions were sprayed by means of a fine paint sprayer on the leaves or plants. With the Piricularia test another form was used (see hereinafter).

With the seed disinfection tests 20 and 10 mgs.. of the substance respectively was rubbed to fineness in a mortar and diluted with 20 and 30 mgs. of talcum respectively.

With the soil disinfection tests (Rhizoctonia solani), like in the leaf tests, the substance was ground in a glass mill with Tween 20.

a. Spore germination test Drops of a series of test suspensions of the substance (concentration series increasing by 0.3 pC unit) mixed with conidea of Fusarium culmorum and Venturia inequalis were put on object glasses. Each object glass was put separately in a closed, moist space at a temperature of 23 C. After 24 hours it was assessed which was the minimum concentration of the substance at which the germination is still completely inhibited (MLD).

b. Phytofthora infestains Cut leaves of tomato plants of therace Bonnibest were sprayed with different concentrations of the suspension of the substance. For this purpose nine leaves were spread horizontally with the bottom side turned upwards on a piece of filtering paper of 1000 ems. and 5 mls. of the suspension was uniformly distributed on this surface by means of an atomizer. The leaves were then put with their stems in a flask containing water. When the sprayed liquid had dried, the leaves were infected with a suspen-= sion containing 100,000 200 spores of the fungus Phyt0f= thora infestans per ml. These 200 spores were obtained from a culture of this fungus on potatoes. The flasks with the leaves were put in a dark space having a relative humidity of 95 to 100% at a temperature of C. After 24 hours the space was illuminated by fluorescent lamps of the day-light type with a light intensity of 3000 to 6000 Lux at the level of the plants; the temperature thus rose to 18 C. After 3 to 4 days black spot had developed on the nontreated control leaves throughout the surface.

0. Cercospora beticola Beet pot plants of the race bison in the 4- to 5-leaf stage were covered by spraying with the test suspensions (5 mls. per 6 plants). After the sprayed liquid had dried, the plants were infected with a suspension of finely ground mycelium of Cercospora beticola cultivated on an agar nutrient (about 500,000 mycelium fragments per ml.). The incubation took place in a climatic room at 21 C., which was illuminated for 16 hours in 24 hours (like with the P. infestans). The relative humidity was raised to the maximum. After about a fortnight typical leaf spots had developed especially on the youngest leaves.

d. Septoria api'i' Cellery pot plants of the race Balder in the 5- to 6- leaf stage were covered by spraying with the test suspensions (5 mls. per 6 plants). After the sprayed liquid had dried, the plants were infected with spores obtained from infected leaves, sprayed in the form of a suspension with 150,000 spores/ml.

The incubation took place in a climatic room at 18 C., illuminated for 16 hours in 24 hours (like with P. infestans). The relative humidity was raised to the maxi= mum. After about a fortnight the typical symptoms of the leaf spot had developed.

f. Plasmopara viticola Small young hothouse-cultivated grape leaves (race Frankenthaler) were covered by half on the bottom side with test suspensions of the substances to be tested, dosage 5 mls./1000 cms.? When the sprayed liquid had dried, the leaves were put on moist paper in Petri dishes. Ten drops of a sporangial suspension of Plasmopara viticola were put on the sprayed and the non-sprayed halves of each leaf (100,000 zoo sporangial per ml.), from infected leaves of previous tests. The incubation took place in a climatic room at 24 C., illuminated for 16 hours in 24 hours (like with P. infestans). The drops were removed by means of filtering paper 24 hours after the application. Six days after the infection the number of downy mildew spots was counted.

g. Botrytis cinerea Salad leaves (dimensions about 4 x 6 cms.) of seedlings cultivated. in the hothouse (race Meikoningin) were covered by half on the bottom side with suspensions of the substances to be tested, dosage 5 mls./ 1000 cms. When the sprayed liquid had dried, the leaves were put on moist filtering paper in Petri dishes. Before the Petri dishes were closed, the leaves were infected with a suspension of finely ground mycelium of a Botrytis conerea, cultivated in a shaking culture.

The incubation took place in a climatic room at 21 C., illuminated for 16 hours in 24 hours (like with P. infestans). After three days necrotic spots had developed throughout the surface of the leaves.

h. Pirz'cularia oryzae Rice sown in pots (about 25 plants per pot of a diameter of 8 cms.) was covered by spraying in the second leaf stage with a test suspension to which 0.05% of Na-oleate and 0.25% of gelatin was added. After the sprayed liquid had dried, the plants were infected by spraying with a suspension of 200,000 spores/mL, obtained from a culture on an agar nutrient of Piricularia oryzae. The incubation took place at a high relative humidity at 23 to 26 C.,

whilst the plants were illuminated for 16 hours in 24 hours by fluorescent lamps. After about 5 days the plants showed the typical leaf blast symptoms.

1''. Venturia inequalis Apple seedlings of a height of about 15 cms. were covered by spraying with the test suspensions up to run off. After the sprayed liquid had dried, each plant was sprayed with 3 mls. of a spore suspension; this spore sus pension, to which a small supply of cherry extract had been added, contained 180,000 conidia per ml. from apple leaves affected by Venturia inequalis. The plants were then placed in the hot-house under a plastics hood and kept thoroughly wet for 48 hours. The hood was then removed. After about a fortnight the plants exhibited the typical scab symptoms.

1:. Duration of activity on tomato leaves The leaves of potted tomato plants of a height of 15 to 20 cms. of the race Bonnibest were sprayed on the top side with the test suspensions. The plants were put in a hot-house. After 96 and 168 hours a different group of plants was sprayed in the same manner with the same sub= stances. After the sprayed liquid had dried, the two groups of plants were infected with a suspension containing 100,= 000 zoo spores of the fungus Phytofthora infestans per ml.; each plant received 1.5 mls. thereof. The plants were placed under a plastics hood and kept wet. After 4 days the leaves not sufficiently protected by the chemical substance showed the typical phytofthora spots.

1. Seed disinfection of wheat grains infected with Fusarium 10 gs. of wheat grains infected by natural agency with Fusarium species was treated with a powder (see 2) of the test substance by rotating the grains and the powder in a. closed box for some time. The treated grains were then spread on moist filtering paper and then held at 10 C. and at 20 C. for three days each. The roots of the re sultant germs exhibited the typical symptoms of affection by Fusarium species.

In. Seed disinfection of beet seed infected by Phoma betea Treatment of 5 gs. of seed as the wheat. The treated seed was sown in troughs containing sterilised sand. The troughs were first kept for 12 days in a refrigerator at 10 C. and then for 9 to 12 days in a Wisconsin tank in a cupboard, the solid temperature being maintained at 10 C. The number of germs affected by Phoma betae was counted.

Soil disinfection The substance to be tested was mixed with nonsterilised soil and then the solid was infected with a quantity of a finely divided shaking culture of Rhizoctonia solani'. Lengths (about 5 cms.) of flax straw were inserted into the soil. After 24 hours these lengths of straw were rinsed in tap water and put horizontally on a 2%-Water agar ground. After 24 hours it was assessed whether round about the straw Rhizoctonia solani started growing.

What is claimed is:

1. A compound selected from the group consisting of the substituted alkylenerhodanides of the formulae @sm-cm-s on,

Kim-Q 3 Oz-C'Hr-S CN,

QSOrCHz-SCN,

(ll-GS 02-CHr-SCN,

l Cl

CN C1 HzC- SOPCHr-SCN and 2. As a substituted alkylenerhodanide of claim 1 a compound of the formula:

3, As a substituted alkylenerhodanide of claim l a compound of the formula:

4i. As a substituted alkyle nerhodanide of claim 1 a compound of the formula:

5 -As a substituted alkylererhodanide of claim 1 a compound of the formula:

14 6. As a substituted alkylererhodanide of claim 1 a compound of the formula:

S Oz-CHg-S CN '7. As a substituted alkylererhodanide of claim 1 a compound of the formula:

Cl SOr-CHz-S ON 8. As a substituted alkylererhodanide of claim 1 a compound of the formula:

CN Cl 9. As a substituted alkylererhodanide of claim 1 a compound of the formula:

Cl 10. As a substituted alkylererhodanide of claim 1 a compound of the formula:

HsCO -S 02-CHz-S CN 11. As a substituted alkylererhodanide of claim 1 a compound of the formula:

12. As a substituted alkylererhodanide of claim 1 a compound of the formula:

1 13. As a substituted alkylererhodanide of claim 1 a compound of the formula:

References Cited UNITED STATES PATENTS OTHER REFERENCES :Goerdeler (II),- Tetrahedron Letters 48, 3665-3666, 1964.

iiBurger, Medicinal Chemistry (Wiley-Interscience NY. 1951), pp. 72-76 C. M. S. JAISLE, Assistant Examiner 11.8. C1. X.R,

Claims (1)

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF THE SUBSTITUTED ALKYLENERHODANIDES OF THE FORMULAE