Patent Publication Number: US-4481027-A

Title: Derivatives of tetrahydrobenzothiazole and herbicidal compositions _containing the same as an active ingredient

Description:
DETAILED EXPLANATION OF THE INVENTION 
     The present invention relates to a novel derivative of tetrahydrobenzothiazole represented by the general formula (I): ##STR4## wherein R 1  represents one of the following groups: ##STR5## wherein R 2  represents a hydrogen atom, methyl group, acetyl group, benzoyl group, phenoxycarbonyl group or 3-pyridylcarbonyl group and R 3  represents a hydrogen atom, hydroxy group, methoxy group or acetoxy group, ##STR6## and a herbicidal composition comprising as the active ingredient at least one of the derivatives of tetrahydrobenzothiazole. 
     As a result of studies on herbicidal composition, the present inventors have found that the derivative of tetrahydrobenzothiazole represented by the general formula (I) has an excellent practical herbicidal effect, and have attained the present invention based on the findings. 
     The compounds represented by the general formula (I) are novel compounds, and of course, the physiological properties of the compounds have never been known. According to the herbicidal tests consisting essentially of foliar application and soil treatment, the derivatives of tetrahydrobenzothiazole according to the present invention (hereinafter referred to as &#34;the present derivatives&#34;) shows an excellent herbicidal activity on broad-leaved weeds, for instance, Stellaria media, Cardamine flexuosa and Portulaca oleracea, Cyperaceous weeds, for instance, Cyperus Iria and Gramineous weeds, for instance, those belonging to the genus Echinochloa and Poa annua, and particularly shows strong herbicidal activity when applied on leaves and stems of these weeds. The application is carried out arable lands such as paddy fields, upland fields, orchards, etc. and non-arable lands. 
     In a first aspect of the present invention, there is provided a derivative of tetrahydrobenzothiazole represented by the general formula (I): ##STR7## wherein R 1  represents one of the following groups: ##STR8## wherein R 2  represents a hydrogen atom, methyl group, acetyl group, benzoyl group, phenoxycarbonyl group or 3-pyridylcarbonyl group and R 3  represents a hydrogen atom, hydroxy group, methoxy group or acetoxy group, ##STR9## 
     In a second aspect of the present invention, there is provided a herbicidal composition comprising as the active ingredient at least one derivative of tetrahydrobenzothiazole represented by the general formula (I): ##STR10## wherein R 1  represents one of the following groups: ##STR11## wherein R 2  represents a hydrogen atom, methyl group, acetyl group, benzoyl group, phenoxycarbonyl group or 3-pyridylcarbonyl group and R 3  represents a hydrogen atom, hydroxy group, methoxy group or acetoxy group, ##STR12## 
     The present derivatives having a herbicidal activity, represented by the general formula (I) are synthesized as follows. 
     Bromodimedone(2-bromo-5,5-dimethyl-1,3-cyclohexanedione) (V) is reacted with a derivative of thiourea, ##STR13## (wherein R 4  represents a hydrogen atom, methyl group or ethyl group), in ethanol under refluxing condition, or in acetic acid in the presence of sodium acetate at 80° to 90° C. to obtain the following intermediate compound (VI). ##STR14## The thus obtained intermediate compound (VI) is further reacted with phenyl chloroformate, ##STR15## to obtain an intermediate compound (VII). ##STR16## 
     In dimethylformamide solvent, phenyl 4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-2-benzothiazolylcarbamate (VII) which had been synthesized from bromodimedone and thiourea is reacted with methylaminoacetaldehyde dimethylacetal to obtain the intermediate compound (VIII) as follows. ##STR17## 
     Then, the thus obtained intermediate compound (VIII) is reacted with an alcohol, preferably ethanol in the presence of dilute inorganic acid as follows. ##STR18## 
     On the other hand, the compound (VI) wherein R 4  represents a hydrogen atom (2-amino-4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-benzothiazole) is reacted with methylisocyanate in dimethylformamide solvent to obtain the intermediate compound (X) as follows. ##STR19## 
     Then, the thus obtained intermediate compound (X) is reacted with glyoxal, OHC--CHO, as follows. ##STR20## 
     Also, the thus obtained intermediate compound (X) is reacted with oxalyl halide, X--CO--CO--X, as follows. ##STR21## 
     Furthermore, the compound (IX) is reacted with an organic acid chloride, ##STR22## (wherein R 5  represents methyl group, phenyl group or phenoxy group) in acetonitrile in the presence of acid-receptor such as tertiary amine, or in basic solvent such as pyridine as follows. ##STR23## 
     Also, the compound (IX) is reacted with methanol in the presence of catalytic amount of concentrated sulfuric acid as follows. ##STR24## 
     Further, the compound (IX) is reacted with alkyl chloride in basic solvent such as pyridine as follows. ##STR25## 
     The compound (XI) is reacted with methanol in the presence of catalytic amount of concentrated sulfuric acid as follows. ##STR26## 
     Also, the compound (XI) is reacted with acetyl chloride in basic solvent such as pyridine as follows. ##STR27## 
     The compound (XVI) is reacted with acetyl chloride in basic solvent such as pyridine as follows. ##STR28## 
     The present derivatives represented by the general formula (I): ##STR29## wherein R 1  represents one of the following groups: ##STR30## wherein R 2  represents a hydrogen atom, methyl group, acetyl group, benzoyl group, phenoxycarbonyl group or 3-pyridylcarbonyl group and R 3  represents a hydrogen atom, hydroxy group, methoxy group or acetoxy group, ##STR31## are concretely shown in Table 1 together with their respective melting points. 
     Infrared absorption spectra of the present derivatives Nos. 1 to 12 are shown respectively in FIGS. 1 to 12. 
     
                                           TABLE 1                                 
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Number of                  Elementary                                     
present                                                                   
      Substituent   Melting                                               
                           analysis                                       
derivative                                                                
      R.sup.1       point (°C.)                                    
                           C:H:N:S + O                                    
                                    IR                                    
__________________________________________________________________________
       ##STR32##    229-230 (with de- composi- tion)                      
                           Calculated 52.9:5.8:14.2:27.1 Found 52.9:5.8:14
                           .2:27.1  FIG. 1                                
2                                                                         
       ##STR33##    153-156                                               
                           Calculated 54.4:6.1:13.6:25.9 Found 53.4:5.6:12
                           .6:28.4  FIG. 2                                
3                                                                         
       ##STR34##    176-178                                               
                           Calculated 60.2:5.3:10.5:24.0 Found 60.2:5.3;10
                           .5:24.0  FIG. 3                                
4                                                                         
       ##STR35##    155-158                                               
                           Calculated 57.8:5.1:10.1:27.0 Found 57.8:5.0:10
                           .0:27.2  FIG. 4                                
5                                                                         
       ##STR36##    128-130 (with de- composition)                        
                           Calculated 54.4:6.1:13.6:25.9 Found 54.4:6.1:13
                           .6:25.9  FIG. 5                                
6                                                                         
       ##STR37##    165-166                                               
                           Calculated 56.3:5.4:15.2:23.1 Found 56.3:5.4:15
                           .2:23.1  FIG. 6                                
7                                                                         
       ##STR38##    216 (with de- composition)                            
                           Calculated 50.2:5.5:13.5:30.8 Found 50.0:5.5:13
                           .5:31.0  FIG. 7                                
8                                                                         
       ##STR39##    168-169                                               
                           Calculated 51.7:5.8:12.9:29.6 Found 51.7:5.8:13
                           .0:29.5  FIG. 8                                
9                                                                         
       ##STR40##    130-132                                               
                           Calculated 52.3:5.7:11.4:30.6 Found 52.3:5.7:11
                           .4:30.6  FIG. 9                                
10                                                                        
       ##STR41##    94-96 (with de- composition)                          
                           Calculated 51.6:5.3:10.6:32.5 Found 51.6:5.3:10
                           .6:32.5  FIG. 10                               
11                                                                        
       ##STR42##    164-165 (with de- composition)                        
                           Calculated 57.0:5.0:14.0:24.0 Found 56.9:5.0:14
                           .1:24.0  FIG. 11                               
12                                                                        
       ##STR43##    216-217                                               
                           Calculated 50.8:4.2:13.7:31.3 Found 50.8:4.3:13
                           .5:31.4  FIG. 12                               
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 Note:                                                                    
 The existence of sulfur was recognized since the present derivatives gave
 positive result when subjected to the sodium nitroprusside reaction.     
 
    
     The present invention will be more precisely explained while referring to Examples as follows. 
     However, the present invention is not restricted to Examples under mentioned. From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention, and without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions. 
    
    
     EXAMPLE 1 
     Synthesis of 1-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxobenzothiazol-2-yl)-3-methyl-5-hydroxy-1,3-imidazolidine-2-one (Present derivative 1) 
     Into a suspension of 28.8 g (0.09 mol) of phenyl 4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-benzothiazol-2-yl-carbamate (VII) in 150 ml of dimethylformamide, 16.3 g (0.136 mol) of dimethylacetal of methylaminoacetaldehyde was added, and the mixture was heated for 3 hours under stirring. 
     After distilling off the solvent, the residue was dissolved in chloroform, and the solution was washed with an aqueous 10% sodium carbonate solution and then with water, and dried on anhydrous sodium sulfate. By distilling off chloroform from the dried solution, 18 g of pale yellow crystals melting at 86°-89° C. were obtained in a yield of 60%. It was confirmed from the infrared absorption spectrum thereof that the crystals were dimethylacetal of 2-[1-methyl-3-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-benzothiazol-2-yl)-ureido]acetaldehyde (VIII). 
     Absorption maxia of infrared absorption spectrum of the product were as follows (KBr tablet): 
     
         νNH-3380, νNHCO-1670 and νCO-1630cm.sup.-1 
    
     Into a mixture of 112.5 ml of ethanol and 150 ml of aqueous 8.8% solution of hydrochloric acid, 18 g (0.053 mol) of the thus obtained compound was dissolved, and after heating the solution under refluxing condition for 30 min, the solution was left as it is in natural cooling to obtain crystals separated out. The crystals were collected by filtration and washed with water and then with warm acetone to be white crystals weighting 6 g and melting at 229° to 230° C. with decomposition. From the infrared absorption spectrum (hereinafter referred to as IR spectrum) and the nuclear magnetic resonance spectrum (hereinafter referred to as NMR spectrum), it was confirmed that the thus obtained compound was present derivative 1. 
     NMR spectrum (in CDCl 3  : δppm): 1.15 (6H, s: methyl at position 5), 2.47 (2H, s: hydrogen at position 4), 2.79 (2H, s: hydrogen at position 6), 3.01 (3H, s: N-methyl at position 3&#39;), 3.32 to 4.05 (2H, m: hydrogen at position 4&#39;), 4.9 (1H, d, J=2 Hz: hydroxyl at position 5&#39;) and 6.11 (1H, dd, J=2 Hz, 7 Hz: hydrogen at position 5&#39;), wherein s means singlet, d means doublet and m means multiplet. 
     In Examples 1-3, designation of protons appearing in nuclear magnetic resonance spectrum of each derivative was carried out as in the structural formula under-mentioned. ##STR44## 
     EXAMPLE 2 
     Synthesis of 1-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxobenzothiazol-2-yl)-3-methyl-5-benzoyloxy-1,3-imidazolidine-2-one (Present derivative 3) 
     Into a solution of 3 g (0.01 mole) of present derivative No. 1 obtained in Example 1 (represented by the formula (IX)) in 60 ml of pyridine, under ice-cooling, 1.7 g (0.012 mol) of benzoyl chloride was added drop by drop, and the mixture was stirred for 10 min. After removing the cooling medium and stirring the mixture for 2 hours, the reaction mixture was poured into 100 ml of water. The thus separated crystals were collected by filtration, washed with water and recrystallized from a mixture of benzene and hexane to be white crystals melting at 176° to 178° C. and weighing 1.8 g. 
     It was confirmed from IR spectrum and NMR spectrum thereof that the crystals were present derivative 3. 
     NMR spectrum (in CDCl 3  : δppm): 1.1 (6H, s: methyl at position 5), 2.47 (2H, s: hydrogen at position 4), 2.75 (2H, s: hydrogen at position 6), 3.11 (3H, s: N-methyl at position 3&#39;), 3.71 (1H, dd, J=2 Hz: hydrogen at position 4&#39;), 4.12 (1H, dd, J=7 Hz, 11 Hz: hydrogen at position 4&#39;), 7.41 (1H, dd, J=2 Hz, 7 Hz: hydrogen at position 5&#39;) and 7.49 to 8.31 (5H, m: aromatic protons) 
     EXAMPLE 3 
     Synthesis of 1-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxobenzothiazol-2-yl)-3-methyl-5-methoxy-1,3-imidazolidine-2-one (Present derivative 5) 
     After having a solution of 3 g (0.01 mol) of present derivative No. 1 (represented by the general formula (IX)) in 120 ml of anhydrous methanol under refluxing condition in the presence of a catalytic amount of concentrated sulfuric acid, the reaction mixture was left as it is to separate out crystals which were collected by filtration. The thus obtained white crystals showed a melting point of 128° to 130° C. with decomposition. The yield was 2.1 g. 
     It was confirmed from the IR spectrum and the NMR spectrum thereof that the thus obtained crytals were present derivative 5. 
     NMR spectrum (in CDCl 3  : δppm): 1.13 and 1.16 (6H, s: methyl at position 5), 2.47 (2H, s: hydrogen at position 4), 2.83 (2H, s: hydrogen at position 6), 3.0 (3H, s: N-methyl at position 3&#39;), 3.5 (1H, dd, J=2 Hz, 11 Hz: hydrogen at position 4&#39;), 3.59 (3H, s: O-methyl at position 5&#39;), 3.8 (1H, dd, J=7 Hz, 11 Hz: hydrogen at position 4&#39;) and 5.99 (1H, dd, J=2 Hz, 7 Hz: hydrogen at position 5&#39;). 
     EXAMPLE 4 
     Synthesis of 1-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-2-benzothiazol-2-yl)-3-methyl-4,5-dihydroxy-1,3-imidazolidine-2-one (present derivative 7) 
     Into 150 ml of ethanol, 5 g (0.02 mol) of N-methyl-N&#39;-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-2-benzothiazolyl)urea (represented by the formula (X)) was added under stirring to prepare a suspension, and an aqueous 40% solution of glyoxal adjusted to pH of 8 to 9 was added drop by drop to the suspension. After heating the mixture under refluxing condition for 7 hours, ethanol was distilled off from the reaction mixture and the residue was extracted with chloroform. By treating the chloroform-extract with a series of conventional procedures, white crystals melting at 216° C. with decomposition were obtained in an amount of 4.1 g, which was identified by IR spectrum and NMR spectrum thereof as present derivative 7. 
     NMR spectrum (DMSO-d 6 ): δppm are as follows: 1.06 (s, 6H: CH 3  at Position 5), 2.44 (s, 2H: H at Position 4), 2.83 (s, 2H: H at Position 6), 2.92 (s, 3H: N--CH 3  at Position 3&#39;), 4.86 (m, 1H: H at Position 4&#39;), 5.6 (m, 1H: H at Position 5&#39;), 6.77 (m, 1H: O--H at position 4&#39;) and 7.37 (m, 1H: O--H at Position 5&#39;). 
     EXAMPLE 5 
     Synthesis of 1-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-2-benzothiazol-2-yl)-3-methyl-1,3-imidazolidine-2,4,5-trione (present derivative 12) 
     Into 30 ml of chloroform, 2.1 g (0.0084 mol) of N-methyl-N&#39;-(4,5,6,7-tetrahydro-5,5-dimethyl-7-oxo-2-benzothiazolyl)urea (represented by the formula (X)) and 1.2 g (0.009 mol) of oxalyl chloride were added, and the mixture was heated under refluxing condition for 30 min. 
     After leaving the reaction mixture to cool, n-hexane was added to the reaction mixture to educe the crystals, which were collected by filteration and recrystallized from a mixed solvent consisting of dimthylformamide and ethanol to obtain 2.4 g of white crystals melting at 216° to 217° C. 
     The thus obtained product was identified as present derivative 12 from the IR spectrum and the NMR spectrum thereof. 
     NMR spectrum (DMSO-d 6 ): δppm are as follows: 1.1 (s, 6H: CH 3  at Position 5), 2.51 (s, 2H: H at Position 4), 2.93 (s, 2H: H at Position 6) and 3.11 (s, 3H: N--CH 3  at Position 38). 
     In the cases where the present derivative represented by the general formula (I) is used as a herbicide, the derivative itself or a composition thereof suitably diluted by a diluent may be applied by a means such as scattering, and also according to the necessity, a composition prepared by further admixing additives such as spreader, wetting agent, sticking agent, etc. may be applied. 
     In addition, there is no possibility of decomposition or denaturation of the present derivative by the other agricultural chemical(s) admixed there with, or decomposition or denaturation of the other agricultural chemicals by the present derivative admixed therewith, and accordingly, any other physiologically active agents, for instance, fungicide(s), insecticide(s), bactericide(s), herbicide(s), plant growth regulator(s), etc. or fertilizer(s) can be admixed therewith or can be used in combination in application. 
     The present invention will be further explained while referring to the preparation examples of the herbicidal compositions wherein the kinds of the active ingredients and additives and the mixing ratio in the composition can be selected from the broad range. 
     PREPARATION EXAMPLE 1 
     Preparation and use of a wettable powder 
     By mixing 50 parts by weight of present derivative 1, 5 parts by weight of a salt of ligninsulfonic acid, 3 parts by weight of a salt of alkylsulfonic acid and 42 parts by weight of diatomaceous earth and pulferizing the mixture, a wettable powder was prepared. 
     The thus prepared wettable powder is applied after diluting with water to a suitable concentration of present derivative 1 as the active ingredient. 
     PREPARATION EXAMPLE 2 
     Preparation and application of an emulsifiable concentrate 
     By uniformly mixing 25 parts by weight of present derivative 2, 65 parts by weight of xylene and 10 parts by weight of polyoxyethylenealkyl aryl ether, an emulsifiable concentrate was prepared. 
     The thus prepared emulsifiable concentrate is applied after diluting with water to a suitable concentration of the active ingredient. 
     PREPARATION EXAMPLE 3 
     Preparation and application of a granular composition 
     After uniformly mixing 8 parts by weight of present derivative 3, 40 parts by weight of bentonite, 45 parts by weight of clay and 7 parts by weight of a salt of ligninsulfonic acid, the mixture was kneaded with water and processed into granules by an extruding granulator. The granules were dried and sifted to be a product of granular composition which is directly applied. 
     The effectiveness of the present derivative is explained while referring to the herbicidal test examples as follows. 
     HERBICIDAL TEST EXAMPLE 1 
     Herbicidal test example by foliar application 
     To the follage of each of the following plants grown from their seeds under a management in a plastic planter of 180×580×150 mm in size filled with a soil collected from an actual crop field, each of the wettable powders prepared as in Preparation Example 1 and diluted respectively to 0.1 and 0.2% by weight of the active ingredient with water was sprayed by a small pressured-sprayer at a rate of 10 liters per are of the surface of the soil in the plastic planter kept in a glass house. 
     After 20 days of the treatment, the state of the plants was observed to assess the damage due to the application of each of the wettable powders to find out the herbicidal activity thereof according to the following criteria: 
     
         ______________________________________                                    
Criteria of herbicidal activity                                           
Index      Phytotoxicity                                                  
______________________________________                                    
0          none                                                           
1          minute                                                         
2          slight                                                         
3          medium                                                         
4          severe                                                         
5          very severe (withered)                                         
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Name of the plants tested                                                 
______________________________________                                    
1.   Echinochloa crus-galli                                               
                        2.     Digitaria ciliaris                         
3.   Poa annua          4.     Portulaca oleracea                         
5.   Chenopodium album  6.     Amaranthus lividus                         
7.   Polygonum longisetun                                                 
                        8.     Cardamine flexuosa                         
9.   Triticum aestivum (Wheat)                                            
                        10.    Zea mays (Maize)                           
11.  Gossypium arboreum (Cotton)                                          
______________________________________                                    
 
    
     The herbicidal activities of the present derivatives thus assessed are shown in Table 2. The growth state of the plants when the present wettable powders were applied was as follows. 
     
         ______________________________________                                    
Those in 2 to 3 leaf-stage:                                               
Echinochloa crus-galli                                                    
                      Digitaria ciliaris                                  
Poa annua             Portulaca oleracea                                  
Chenopodium album     Amaranthus lividus                                  
Polygonum longisetum                                                      
Triticum aestivum and Zea mays                                            
That in 3 to 4 leaf-stage:                                                
Cardamine flexuosa                                                        
That in the first true leaf-stage:                                        
Gossypium arboreum                                                        
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                                           TABLE 2                                 
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Herbicidal Activity                                                       
           Present derivative                                             
                                    Not                                   
           1    2   3   4   5   6   treated                               
           Concentration %                                                
Plant      0.1*                                                           
              0.2                                                         
                0.1                                                       
                  0.2                                                     
                    0.1                                                   
                      0.2                                                 
                        0.1                                               
                          0.2                                             
                            0.1                                           
                              0.2                                         
                                0.1                                       
                                  0.2                                     
                                    --                                    
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Echinochloa crus-galli                                                    
           1  3 4 4 1 2 0 2 2 3 1 3 0                                     
Digitaria ciliaris                                                        
           2  3 3 4 0 2 2 3 3 3 2 3 0                                     
Poa annua  3  4 4 5 1 3 1 3 3 4 1 3 0                                     
Portulaca oleracea                                                        
           3  4 4 5 0 1 4 5 3 5 2 4 0                                     
Chenoposium album                                                         
           5  5 5 5 2 3 2 4 5 5 3 4 0                                     
Amaranthus lividus                                                        
           5  5 5 5 2 2 3 4 5 5 3 4 0                                     
Polygonum longisetum                                                      
           5  5 5 5 0 2 3 4 5 5 3 4 0                                     
Cardamine flexuosa                                                        
           4  5 4 5 2 3 5 5 4 5 4 5 0                                     
Triticum aestivum                                                         
           3  4 4 4 0 0 0 0 2 4 3 3 0                                     
Zea mays   0  0 0 0 0 1 0 0 0 0 0 0 0                                     
Gossypium arboreum                                                        
           5  5 5 5 1 1 4 4 5 5 4 4 0                                     
__________________________________________________________________________
 Note:                                                                    
 Concentration, % by weight, of each active ingredient in the dilute      
 wettable power with water, applied to the plants.                        
 
    
     HERBICIDAL TEST EXAMPLE 2 
     Herbicidal tests by foliar application of the present compound 
     To the seedlings of the plants shown below respectively grown from the seeds sown in a soil collected from a field and packed in a planter of a size of 650×210×200 mm, under a growth management in a green house, an aqueous suspension containing 0.2% by weight of each of the present compound prepared by diluting each of the wettable powders (so-called wettable compositions) prepared as Preparation Example 1 was sprayed from a small sprayer at a rate of 10 liters per are of the soil surface to sufficiently wet the foliage of the plants. After 20 days of the treatment, the state of the plants was surveyed according to the following standard of phytotoxic symptoms. 
     For reference, the growth state of the respective plant species at the time of spraying was as follows. Growth state: 
     
         ______________________________________                                    
Species          State of growth                                          
______________________________________                                    
Echinochloa crus-galli                                                    
                 2-3 leaf stage                                           
Poa annua        2-3 leaf stage                                           
Stellaria media  5-6 leaf stage                                           
Portulaca oleracea                                                        
                 5-6 leaf stage                                           
Cardamine flexuosa                                                        
                 5-6 leaf stage                                           
Rice             2-3 leaf stage                                           
Wheat            2-3 leaf stage                                           
Maize            2-3 leaf stage                                           
Cucumber         2-3 leaf stage                                           
Tomato           2-3 leaf stage                                           
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Standard of recording phytotoxic symptoms.                                
Index      Phytotoxicity                                                  
______________________________________                                    
0          none                                                           
1          minute                                                         
2          slight                                                         
3          medium                                                         
4          severe                                                         
5          very severe (withered)                                         
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     The results of survey of phytotoxicity are shown in Table 3. 
     
                       TABLE 3                                                     
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Herbicidal Activity                                                       
           Present derivative No.                                         
                                            Not                           
Plant        7     8     9   10   11   12   treated                       
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Echinochloa crus-galli                                                    
             5     4     4   3    5    2    0                             
Poa annua    5     3     4   3    5    2    0                             
Stellaria media                                                           
             5     5     5   4    4    5    0                             
Portulaca oleracea                                                        
             5     5     5   4    3    5    0                             
Cardamine flexuosa                                                        
             5     5     5   4    5    5    0                             
Rice         5     4     5   3    4    5    0                             
Wheat        5     3     3   3    3    5    0                             
Maize        5     2     5   4    0    1    0                             
Cucumber     5     5     4   5    2    5    0                             
Tomato       5     5     5   5    5    5    0                             
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     HERBICIDAL TEST EXAMPLE 3 
     Herbicidal tests by foliar application of the present compound 
     To the seedlings of the plants shown below respectively grown from the seeds sown in a field (1 m×1 m), an aqueous suspension containing respective 0.5 and 0.1% by weight of each of the present compound prepared by diluting each of the wettable powders (so-called wettable compositions) prepared as Preparation Example 1 and alkylphenolpolyethylene glycolether as a spreader agent was sprayed from a small sprayer at a rate of 10 liters per are of the soil surface to sufficiently wet the foliage of the plants. After 20 days of the treatment, the plants of the remaining treated plants above ground were weight (without drying) and the value thereof represented by A g/unit area was compared with that of the untreated plants represented by B g/unit area. 
     The results are shown by A/B (%) in Table 4. 
     
                                           TABLE 4                                 
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            Present derivative No.                                        
            1     2      4    5      7    8    9    10   12               
            Concentration (%)                                             
Plant       0.05                                                          
                0.1                                                       
                  0.05                                                    
                      0.1                                                 
                         0.05                                             
                            0.1                                           
                              0.05                                        
                                 0.1 0.05                                 
                                        0.01                              
                                          0.05                            
                                             0.1                          
                                               0.05                       
                                                  0.1                     
                                                    0.05                  
                                                       0.1                
                                                         0.05             
                                                            0.1           
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Portulaca oleracea                                                        
            0    0                                                        
                  0   0  35  0                                            
                              33 0   0   0                                
                                           0  0                           
                                                0  0                      
                                                    19  0                 
                                                         0   0            
Amaranthus lividus                                                        
            0    0                                                        
                  0   0  87 55                                            
                              43 0   0   0                                
                                          11  0                           
                                               14  9                      
                                                    23  5                 
                                                         0   0            
Chenopodium album                                                         
            0    0                                                        
                  0   0  93 86                                            
                              45 0   0   0                                
                                          14  0                           
                                               17  0                      
                                                    13  7                 
                                                         0   0            
Glycine max (Soybean)                                                     
            98  96                                                        
                  109 97 96 96                                            
                              111                                         
                                 103 84 39                                
                                          93 91                           
                                               97 93                      
                                                    98 91                 
                                                         102              
                                                            100           
Glycine max (Soybean)                                                     
            115 97                                                        
                  93  95 97 94                                            
                              102                                         
                                 99  92 48                                
                                          99 97                           
                                               96 94                      
                                                    96 94                 
                                                         109              
                                                            98            
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