Preparation and application of pyridine compounds containing 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime units

Abstract

The present invention relates to the preparation and application of a pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-formaldehyde oxime unit. The pyridine compound is obtained by condensing 1,3-dimethyl-5-aryloxypyrazole-4-formaldehyde oxime with substituted pyridine methyl chloride. The pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-formaldehyde oxime unit shows a good control effect on harmful insects, and the compound is used to prepare insecticides in the fields of agriculture, gardening, etc.

Description

Technical Field

[0001] The invention relates to the field of chemical pesticides, and in particular to the preparation and application of a pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit. Background Art

[0002] Pest control is an important research topic in the field of plant protection. Pesticides can effectively control pests. However, in recent years, some pests have developed resistance to traditional pesticides. Therefore, researchers need to continuously develop new and efficient pesticides.

[0003] The pyridine ring is an important active fragment of drug molecules, and its pyridine compounds play an important role in agricultural production.

[0004] As a common active unit of pesticide molecules, pyrazole oxime also has excellent insecticidal effects in the pesticide field.

[0005] Therefore, in order to continue to search for new compounds with good insecticidal activity from pyridine derivatives, the pyrazole oxime unit structure and the substituted pyridine fragment are organically connected together. The present invention discloses a pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit with agricultural insecticidal application value. Summary of the invention

[0006] The purpose of the present invention is to provide a pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit which has good insecticidal effect on pests such as armyworms and mites and is highly effective, so as to meet the demand for highly effective insecticides in crop protection.

[0007] Another object of the present invention is to provide the use of the above compounds in preparing insecticides.

[0008] Another object of the present invention is to provide a method for preparing the above compound.

[0009] In order to solve the above technical problems, the first aspect of the present invention provides a pyridine compound containing a 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit, having the following structure:

[0010]

[0011]

[0012] The second aspect of the present invention provides a method for preparing the pyridine compound containing the 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit, which comprises the following reaction steps:

[0013]

[0014]

[0015] Among them, the synthesis of 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime intermediate and substituted pyridylmethyl chloride intermediate are prepared by conventional synthesis methods.

[0016] The compounds of the present invention show good insecticidal effects on insect pests such as armyworms and mites, so the compounds of the present invention can be used to prepare insecticides to protect agricultural and horticultural plants. Of course, the pests that can be controlled by the compounds of the present invention are not limited to the above examples.

[0017] When the compounds of the present invention are used as pesticides in the fields of agriculture, horticulture, etc., they can be used alone or in the form of insecticide compositions, such as using the compounds of the present invention as active ingredients and adding pesticide adjuvants commonly used in the art to process them into aqueous emulsions, suspensions, water-dispersible granules, emulsifiable concentrates, etc.

[0018] Commonly used pesticide adjuvants include: liquid carriers, such as water; organic solvents such as toluene, xylene, cyclohexanol, methanol, butanol, ethylene glycol, acetone, dimethylformamide, acetic acid, dimethyl sulfoxide, animal and vegetable oils and fatty acids; commonly used surfactants such as emulsifiers and dispersants, including anionic surfactants, cationic surfactants, nonionic surfactants and amphoteric surfactants; other adjuvants, such as wetting agents, thickeners, etc.

[0019] When the compound of the present invention is used as an active ingredient in an insecticide, the content in the insecticide is selected within the range of 0.1% to 99.5%, and the appropriate active ingredient content can be determined according to the formulation form and the application method. Usually, the active ingredient is contained in an aqueous emulsion at 5% to 50% (weight percentage, the same below), preferably 10% to 40%; the active ingredient is contained in a suspension at 5% to 50%, preferably 5% to 40%.

[0020] For the use of the pesticide of the present invention, commonly used application methods can be selected, such as stem and leaf spraying, water surface application, soil treatment and seed treatment, etc. For example, when stem and leaf spraying is adopted, the compound as the active ingredient can be used in a concentration range of 1 to 1000 μg / mL of aqueous emulsion, suspension, water dispersible granule, emulsifiable concentrate, preferably in a concentration range of 1 to 500 μg / mL.

[0021] The pyridine compound containing 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit disclosed in the present invention has good insecticidal effect on insect pests such as armyworms and mites, and can therefore be used to prepare insecticides for use in agriculture, horticulture and other fields. DETAILED DESCRIPTION

[0022] The above scheme is further described below in conjunction with specific examples. These examples are used to illustrate the present invention but are not limited to the scope of the present invention. The implementation conditions used in the examples can be further adjusted according to the conditions of the specific manufacturer, and the unspecified implementation conditions are usually the conditions in conventional experiments.

[0023] Embodiment 1:

[0024]

[0025] Dissolve 4 mmol of intermediate IIIa in 50 mL of 2-butanone, then add 8 mmol of potassium carbonate and 3 mmol of intermediate IIa. Heat the reaction solution under reflux for 8 hours. Stop the reaction, remove the solvent, and separate the crude product by column chromatography to obtain compound Ia; 1 H NMR (400MHz, CDCl3) δ8.35(d,J=2.30Hz,1H),7.74(s,1H),7.57(d,J=6.20Hz,2H),7.39(d,J=6.20Hz,4H),7.36(s,1H ),7.31(d,J=8.30Hz,1H),6.82(d,J=8.30Hz,1H),6.74(d,J=8.40Hz,2H),4.87(s,2H),3.57(s,3H),2.31(s,3H).HRMS calcd for C 24 H 22 BrN4O2S[M+H] + 509.0647, found 509.0650.

[0026] Embodiment 2:

[0027]

[0028] Dissolve 5 mmol of intermediate IIIa in 55 mL of acetonitrile, then add 12 mmol of 4-dimethylaminopyridine (DMAP) and 4 mmol of intermediate IIb. Heat the reaction solution under reflux for 11 hours. Stop the reaction, remove the solvent, and separate the crude product by column chromatography to obtain compound Ib; 1H NMR (400MHz, CDCl3) δ8.32(d,J=2.30Hz,1H),7.75(s,1H),7.52~7.61(m,2H),7.40(t,J=2.80Hz,3H),7.29~7.32(m,1H),7.18(t HRMS calcd for C 24 H 22 ClN4O2S[M+H] + 465.1152, found 465.1155.

[0029] Embodiment 3:

[0030]

[0031] Dissolve 5 mmol of intermediate IIIa in 65 mL of DMF, then add 10 mmol of potassium carbonate and 5.5 mmol of intermediate IIc. Heat the reaction solution to 55°C and stir for 6 hours. Stop the reaction, remove the solvent, and separate the crude product by column chromatography to obtain compound Ic; 1 H NMR (400MHz, CDCl3) δ8.33 (d, J = 2.20Hz, 1H), 7.72 (s, 1H), 7.54~7.56 (m, 2H), 7.35~7.42 (m, 3H), 7. 32~7.34(m,1H),6.91~6.99(m,2H),6.74~6.83(m,3H),4.87(s,2H),3.56(s,3H),2.30(s,3H).HRMS calcd for C 24 H 22 FN4O2S[M+H] + 449.1447, found 449.1452.

[0032] Embodiment 4:

[0033]

[0034] Dissolve 3 mmol of intermediate IIIa in 50 mL of N,N-dimethylacetamide (DMA), then add 9 mmol of sodium acetate and 3 mmol of intermediate IId. Heat the reaction solution to 80°C and stir for 10 hours. Stop the reaction, remove the solvent, and separate the crude product by column chromatography to obtain compound Id; 1H NMR (400MHz, CDCl3) δ8.35(d,J=2.20Hz,1H),7.67(s,1H),7.56~7.59(m,2H),7.38~7.41(m,3H),7.32~7.34(m,1H),7.00(s ,1H),6.77~6.86(m,2H),6.38(d,J=8.30Hz,1H),4.90(s,2H),3.57(s,3H),2.31(d,J=7.50Hz,6H),2.24(s,3H).HRMScalcd for C 26 H 27 N4O2S[M+H] + 459.1855, found 459.1858.

[0035] Embodiment 5:

[0036]

[0037] Dissolve 8 mmol of intermediate IIIb in 60 mL of DMF, then add 15 mmol of sodium carbonate and 6 mmol of intermediate IIa. Heat the reaction solution to 80°C and stir for 12 hours. Stop the reaction, remove the solvent, and separate the crude product by column chromatography to obtain compound Ie; 1 H NMR (400MHz, CDCl3) δ8.31(d,J=2.30Hz,1H),7.72(s,1H),7.45(d,J=8.20Hz,2H),7.29~7.38(m, 5H),6.85(d,J=8.20Hz,1H),6.72(d,J=8.50Hz,2H),4.86(s,2H),3.55(s,3H),2.29(s,3H).HRMS calcd for C 24 H 21 BrClN4O2S[M+H] + 543.0257, found 543.0256.

[0038] Embodiment 6:

[0039] Insecticidal activity test of samples against armyworms

[0040] The leaf dipping method proposed by the International Resistance Action Committee (IRAC) was used: the target for the test was armyworm. An appropriate amount of corn leaves were fully soaked in the prepared solution and then dried naturally in the shade. They were placed in a culture dish lined with filter paper, and the 3rd instar larvae of armyworm were inoculated. The leaves were placed in an observation room at 25°C and cultured. The results were investigated after 48 hours. The insect body was touched with a brush, and no reaction was considered dead. The test concentration was 500μg / mL (other concentrations of the solution can be obtained by diluting the 500μg / mL solution).

[0041] Embodiment 7:

[0042] Insecticidal activity test of samples against mites

[0043] The spray method proposed by the International Resistance Action Committee (IRAC) was used: the target was Tetranychus cinnabarinus, and broad bean leaves infested with Tetranychus cinnabarinus were sprayed under a Potter spray tower. After treatment, the Tetranychus cinnabarinus was cultured in a 25°C observation room, and the results were investigated 48 hours later. The insect body was touched with a brush, and no reaction was considered dead. The test concentration was 500μg / mL (other concentrations of the solution can be obtained by diluting the 500μg / mL solution).

[0044] The insecticidal activity test results (Table 1) show that when the test concentration is 500 μg / mL, the killing effects of compounds Ⅰa~Ⅰe on armyworms are all 100%, and at 100 μg / mL, the killing activities of compounds Ⅰa~Ⅰe on armyworms are 100%, 60%, 100%, 50% and 60%, respectively; when the test concentration is 500 μg / mL, the killing effects of compounds Ⅰa~Ⅰe on cinnabarinus spider mites are 100%, 60%, 100%, 100% and 80%, respectively, and at 100 μg / mL, the inhibitory activities of compounds Ⅰa, Ⅰc and Ⅰd on cinnabarinus spider mites are 40%, 50% and 50%, respectively.

[0045] Table 1. Preliminary insecticidal activity data of Ia~Ie

[0046]

[0047] The above experimental data show that the new compound obtained by organically linking the pyrazole oxime unit structure with the substituted pyridine fragment has good insecticidal activity.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above examples. The above examples and descriptions are only for explaining the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A pyridine compound (I) containing a 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit, characterized in that The structure is:

2. The method for preparing the pyridine compound (I) containing 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit according to claim 1, characterized in that Here’s how:

3. Use of the pyridine compound (I) containing 1,3-dimethyl-5-aryloxypyrazole-4-carbaldehyde oxime unit as claimed in claim 1 in the preparation of an insecticide.

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