5H-[1, 2, 4] triazinyl [5, 6-b] indole derivatives containing disulfide structure, and preparation method and application thereof

Abstract

The invention discloses a series of disulfide structure-containing 5H-[1, 2, 4] triazinyl [5, 6-b] indole derivatives which are synthesized by taking a 5H-[1, 2, 4] triazinyl [5, 6-b] indole-3-thioketone structure as a lead compound and thiol containing alkyl or aryl as a linking group and grafting different pharmacophores on the basis of the linking group, and a preparation method of the disulfide structure-containing 5H-[1, 2, 4] triazinyl [5, 6-b] indole derivatives comprises the following steps: synthesizing a series of disulfide structure-containing 5H-[1, 2, 4] triazinyl [5, 6-b] indole derivatives; the compound has an excellent inhibition effect on plant pathogenic bacteria such as Xanthomonas oryzae pv. Oryzae and Xanthomonas citri pv. Citri. Part of the compounds show excellent inhibitory activity on Xanthomonas oryzae pv. Oryzae, and EC50 of the compounds can reach 0.77-0.85 [mu] g / mL; part of the compounds show excellent inhibitory activity on citrus canker pathogen, and EC50 of the compounds is 2.62 mu g / mL; the disulfide structure 5H-[1, 2, 4] triazinyl [5, 6-b] indole derivative disclosed by the invention can be used for preparing pesticides for resisting plant pathogenic bacteria and fungi, and has extremely high research value.

Description

Technical Field

[0001] The present invention relates to the technical field of pharmaceutical chemistry, and in particular to 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure, and preparation methods and applications thereof. Background Art

[0002] Plant bacterial diseases are one of the most destructive plant diseases, which not only affect the healthy and stable development of agriculture, but also pose a major threat to food safety. Among them, bacterial diseases caused by Xanthomonas oryzae pv. Oryzae (Xoo), Xanthomonas axonopodis pv. Citri (Xac), and Pseudomonas syringae pv. Actinidiae (Psa) cause agricultural losses of hundreds of millions of dollars each year.

[0003] The application of chemical pesticides has always been the main measure for preventing and controlling bacterial diseases of plants. It has the advantages of a wide spectrum of fungicides, rapid effects, and low costs. However, the long-term application of chemical pesticides inevitably leads to pesticide residues and environmental pollution, which poses great challenges to human health and ecological balance. In addition, many commercial pesticides have developed resistance problems to varying degrees. Therefore, it is urgent to find highly active, low-resistance compounds for resisting plant pathogenic bacteria, and on this basis, create new green pesticides with independent intellectual property rights to provide candidate drugs for the prevention and control of bacterial diseases of crops.

[0004] There are a large number of studies on the biological activity of 5H-[1,2,4]triazine[5,6-b]indole compounds and nitrogen-containing heterocyclic compounds. Therefore, how to continue to use the 5H-[1,2,4]triazine[5,6-b]indole structure as a lead compound and use disulfide groups for skeleton transition to find active target compounds with high bactericidal efficiency is an urgent problem to be solved. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a triazine compound containing a disulfide structure and a preparation method and application thereof. Taking 5H-[1,2,4]triazine[5,6-b]indole-3-thione as the parent structure and utilizing the skeleton transition method, a series of triazine compounds containing a disulfide structure are synthesized, and their biological activities are investigated, thereby providing an important scientific basis for the research and development and creation of new pesticides.

[0006] To achieve the above purpose, the present invention is implemented through the following technical solutions:

[0007] The present invention discloses a triazine compound containing a disulfide structure, the general structural formula of which is shown in the following formula (I):

[0008]

[0009] Wherein, R1 is selected from any substituted or unsubstituted alkyl, any substituted or unsubstituted cycloalkyl and any substituted or unsubstituted aryl or benzyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

[0010] Preferably, R1 is selected from C2-C8 alkyl, substituted or unsubstituted C6-C7 aryl, substituted or unsubstituted benzyl, wherein the substitution refers to one or more substitutions of halogen, methyl, methoxy, trifluoromethyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

[0011] Preferably, R1 is selected from ethyl, propyl, allyl, n-butyl, n-hexyl, n-heptyl, octyl, deoxynyl, dodecyl, substituted or unsubstituted phenyl, substituted or unsubstituted benzyl, wherein the substitution refers to one or more substitutions selected from methyl, methoxy, halogen, trifluoromethyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

[0012] The present invention discloses a triazine compound containing a disulfide structure, specifically comprising the following compounds:

[0013]

[0014] The preparation method of the triazine compound containing a disulfide structure of the present invention comprises the following steps:

[0015] (1) Dissolving isotonic acid and potassium carbonate in water by stirring, then slowly adding thiosemicarbazide, and reacting by reflux and stirring at 100° C. After the reaction is completed, filtering is performed, and the pH of the obtained liquid is adjusted with acetic acid. Solids precipitate, and are filtered again by suction, and washed with a large amount of water to obtain a compound;

[0016] (2) Dissolve the compound obtained in step (1) in dimethyl sulfoxide, add it to a dichloromethane solution, stir evenly, slowly add 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and stir the reaction in an ice bath; after the reaction is completed, filter and separate to obtain the target compound. The chemical formula is as follows:

[0017]

[0018] A composition, comprising the compound represented by the above formula (I) or its stereoisomer, or its salt or solvate, or the prepared compound represented by the formula (I) or its stereoisomer, or its salt or solvate, and agricultural adjuvant, fungicide, insecticide or herbicide; the dosage form of the composition is selected from: emulsifiable concentrate (EC), dust (DP), wettable powder (WP), granule (GR), aqueous solution (AS), suspension (SC), ultra low volume spray (ULV), soluble powder (SP), microcapsule (MC), smoke agent (FU), emulsion in water (EW) or water dispersible granule (WG) One or more.

[0019] The compound represented by formula (I) or the prepared compound represented by formula (I) or the composition is used in preventing and controlling agricultural pests and diseases. The agricultural pests and diseases are plant bacterial diseases and fungal diseases. The agricultural pests and diseases include plant pathogenic bacteria such as rice bacterial blight pathogenic bacteria, Xanthomonas oryzae pv. oryzae, carpet Xanthomonas, campestris pv. rapeseed, Pseudomonas syringae tomato leaf spot pathogenic type, Pseudomonas syringae kiwifruit pv., Ralstonia solanacearum, Pseudomonas syringae cucumber angular spot pathogenic type, Pseudomonas solanacearum, Xanthomonas solanacearum soybean pv. or Corynebacterium michiganensis ulcer pathogenic bacteria, and plant pathogenic fungi such as Botrytis cinerea, Fusarium oxysporum, Colletotrichum solani, Colletotrichum gloeosporioides, Colletotrichum sorghum and so on.

[0020] Preferably, the bacterial disease is any one of rice bacterial blight, citrus canker, and kiwi canker. Preferably, the fungal disease is any one of Botrytis cinerea, Gibberella fusca, and Rhizoctonia solani.

[0021] The present invention also provides a method for controlling agricultural pests and diseases using the triazine compound containing a disulfide structure and the composition, comprising allowing the triazine compound containing a disulfide structure or its salt or solvate, or the composition to act on harmful substances or their living environment.

[0022] The term "alkyl" used herein includes straight chain saturated or unsaturated hydrocarbon groups having a specific number of carbon atoms. For example, "C2-8 alkyl" (or allyl) refers to C2, C3, C4, C5, C6, C7, C8 alkyl.

[0023] The term "substituted" as used herein refers to the replacement of any one or more hydrogen atoms on a designated atom or group with a selected designated group, provided that the general valence of the designated atom is not exceeded. If not otherwise specified, the substituents are named to the central structure. For example, it is understood that when (cycloalkyl) alkyl is a possible substituent, the point of attachment of the substituent to the central structure is in the alkyl portion. A ring double bond as used herein is a double bond formed between two adjacent ring atoms (such as C=C, C=N or N=N). When referring to substitution, especially polysubstitution, it is meant that multiple substituents are substituted at various positions on the designated group, such as dichlorophenyl refers to 1,2-dichlorophenyl, 1,3-dichlorophenyl and 1,4-dichlorophenyl.

[0024] Combinations of substituents and or variables are permitted only if these combinations result in stable compounds or useful synthetic intermediates. A stable compound or stable structure implies that the compound is sufficiently stable when isolated from a reaction mixture in a useful purity and then formulated to form an effective therapeutic agent. Preferably, the present compound does not contain -F / -Cl halogen, N-CH3, allyl, aromatic, benzyl or C3-C8 alkane chains.

[0025] The term "aryl" refers to a monocyclic aromatic hydrocarbon group having 6 or 7 carbon atoms in the ring portion, such as phenyl and benzyl.

[0026] The term "halogen" or "halogen atom" refers to chlorine and fluorine.

[0027] If not otherwise specified, the compounds of the present invention are understood to include free states and salts thereof. The term "salt" means acidic and / or basic salts formed with inorganic and / or organic acids and bases. In addition, the term "salt" may include zwitterions (inner salts), such as when the compound of formula I contains a basic fragment such as an amine or a pyridine or imidazole ring, and an acidic fragment such as a carboxylic acid. Pharmaceutically acceptable (i.e., non-toxic, physiologically acceptable) salts are preferred, such as acceptable metal and amine salts, in which the cation does not significantly contribute to the toxicity or biological activity of the salt. However, other salts may be useful, such as separation or purification steps used in the preparation process, and are therefore also included in the scope of the present invention.

[0028] Compared with the prior art, the present invention has the following beneficial effects: the present invention uses a 5H-[1,2,4]triazine[5,6-b]indole-3-thione structure as a lead compound, and then uses an alkyl or aryl thiol as a linker, and on this basis connects different pharmacophores. A series of 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure are synthesized, and the compounds have excellent inhibitory effects on plant pathogenic bacteria such as rice bacterial blight and citrus canker.

[0029] (1) In the in vitro test, the target compounds showed good antibacterial activity against Xanthomonas oryzae pv.oryzae (Xoo) and Xanthomonas oryzae pv.oryzae (Xoo). 50 The compound 1 showed excellent inhibitory activity against Xanthomonas axonopodispv. citri (Xac), and its EC 50 It is 2.62μg / mL, and can be used to prepare pesticides against plant pathogenic bacteria.

[0030] (2) The target compounds showed good inhibitory activity against plant pathogenic bacteria such as Xanthoceras oryzae. Most of the compounds containing ethyl groups in their structures showed good inhibitory activity against Xanthoceras oryzae. 50 All of them were within 10, especially the EC value of compound 1 against Xanthomonas oryzae 50 The EC value of compound 16 against Xanthomonas citri ulcerans was 0.77 μg / mL. 50 The EC value of compound 6 against kiwifruit canker pathogen was 3.43 μg / mL. 50 The target compounds also showed certain inhibitory activity against plant pathogenic fungi. At a concentration of 50 μg / mL, all target compounds had good biological activity against Rhizoctonia solani. Among them, compound 33 had excellent inhibitory activity against Rhizoctonia solani, Botrytis cinerea and Gibberella fusca, with inhibition rates of 92.35%, 75.81% and 61.33%, respectively. Therefore, it can be seen that such compounds can be used as new anti-plant pathogenic bacteria and fungal pesticides, and have extremely high research value. It provides an important scientific basis for the research and development and creation of new pesticides. DETAILED DESCRIPTION

[0031] The following will be clearly and completely described in conjunction with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise specified, the technical means used in the implementation examples are conventional means well known to those skilled in the art.

[0032] Example 1

[0033] (1) Preparation of intermediate 5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0034]

[0035] In a 250mL round-bottom flask, add the compound isatin (3.00g, 20mmol) and potassium carbonate (4.23g, 30mmol), add water and stir, then add thiosemicarbazide (1.86g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 46.50%. Its NMR data are: 1 H NMR (400MHz, DMSO-d6) δ13.48(s,1H,-NH),13.10(s,1H,-NH),7.32(dd,J=7.8,1.6Hz,1H,Ar-H),7.09(ddd ,J=8.6,7.1,1.6Hz,1H,Ar-H),6.68(dd,J=8.2,1.2Hz,1H,Ar-H),6.53(ddd,J=8.1,7.2,1.2Hz,1H,Ar-H); 13 C NMR(101MHz,DMSO-d6)δ173.41,153.33,148.17,147.74,131.03,130.80,115.89,115.29,115.22; HRMS(ESI)[M+H] + calcd for C9H7N4S:203.0386,found:203.0378.

[0036] (2) Preparation of intermediate 5-methyl-5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0037]

[0038] In a 250mL round-bottom flask, add compound 1-methyl isatin (3.00g, 20mmol) and potassium carbonate (3.90g, 30mmol), add water and stir, then add thiosemicarbazide (1.71g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 5-methyl-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 32.70%. Its NMR data is: 1 H NMR (600MHz, DMSO-d6) δ8.12–7.95(m,1H,Ar-H),7.78–7.59(m,2H,Ar-H),7.48–7.33(m,1H,Ar-H),3.65(s,3H,-CH3). 13C NMR(151MHz,DMSO-d6)δ179.51,148.69,144.82,135.81,132.30,124.00,122.20,117.85,112.09,27.98.HRMS(ESI)[M+H] + Calculate for C 10 H9N4S:217.0542,found:217.0535.

[0039] (3) Preparation of intermediate 6-methyl-5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0040]

[0041] In a 250mL round-bottom flask, add compound 7-methyl isatin (3.00g, 20mmol) and potassium carbonate (3.90g, 30mmol), add water and stir, then add thiosemicarbazide (1.71, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 6-methyl-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 33.50%. Its NMR data are: 1 H NMR (600MHz, DMSO-d6) δ12.45(s,1H,-NH),7.34(d,J=114.6Hz,1H,Ar-H),7.05(d,J=44.8Hz,2H,Ar-H),6.49(s,1H,Ar-H),2.09(s,3H,-CH3); 13 C NMR(151MHz,DMSO-d6)δ173.65,153.45,148.84,145.57,131.74,128.86,123.59,122.54,119.70,115.28,18.45.HRMS(ESI)[M+H] + Calculate for C 10 H9N4S:217.0542,found:217.0533.

[0042] (4) Preparation of intermediate 6-fluoro-5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0043]

[0044] In a 250mL round-bottom flask, add compound 7-fluoroindigo red (3.00g, 20mmol) and potassium carbonate (3.80g, 30mmol), add water and stir, then add thiosemicarbazide (1.67g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 6-fluoro-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 40.00%. Its NMR data are: 1 H NMR (600MHz, DMSO-d6) δ7.82 (d, J=7.8Hz, 1H, Ar-H), 7.53 (dd, J=10.9, 8.2Hz, 1H, Ar-H), 7.32 (td, J=8.2, 4.6Hz, 1H, Ar-H). 13 C NMR(151MHz,DMSO-d6)δ179.93,150.16(d, 1 J C-F =228.5Hz),148.21,135.87,130.96(d, 2 J C-F =14.5Hz),124.43(d, 3 J C-F =6.2Hz),121.59(d, 3 J C-F =5.9Hz),118.42(d, 4 J C-F =3.7Hz),118.26(d, 2 J C-F =17.1Hz). 19 F NMR(565MHz,DMSO-d6)δ-131.09.HRMS(ESI)[M+H] + calcd for C9H6N4FS:221.0292,found:221.0284.

[0045] (5) Preparation of intermediate 7-fluoro-5H-[1,2,4]triazine[5,6-b]indole indole-3-thione:

[0046]

[0047] In a 250mL round-bottom flask, add compound 6-fluoroindigo red (3.00g, 20mmol) and potassium carbonate (3.80g, 30mmol), add water and stir, then add thiosemicarbazide (1.67g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 7-fluoro-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 49.80%. Its NMR data is: 1 H NMR (500MHz, Trifluoroacetic Acid-d) δ8.78–8.68(m,1H,Ar-H),7.87(dd,J=8.1,2.2Hz,1H,Ar-H),7.80–7.72(m,1H,Ar-H). 13 C NMR(126MHz,Trifluoroacetic Acid-d)δ168.88,166.07(d, 1 J C-F =236.8Hz),147.58,144.68(d, 3 J C-F =13.1Hz),140.29,126.36(d, 4 J C-F =3.2Hz),115.24(d, 2 J C-F =24.9Hz),113.00(d, 3 J C-F =11.2Hz),102.80(d, 2 J C-F =28.7Hz). 19 FNMR(471MHz,Trifluoroacetic Acid-d)δ-77.53.HRMS(ESI)[M+H] + calcd for C9H6N4FS:221.0292,found:221.0284.

[0048] (6) Preparation of intermediate 8-fluoro-5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0049]

[0050] In a 250mL round-bottom flask, add compound 6-fluoroindigo red (3.00g, 20mmol) and potassium carbonate (3.80g, 30mmol), add water and stir, then add thiosemicarbazide (1.67g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with water. Dry to obtain the intermediate 7-fluoro-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 55.50%. Its NMR data is: 1 H NMR (600MHz, DMSO-d6) δ7.25 (dd, J=10.3, 2.9Hz, 1H, Ar-H), 6.99 (td, J=8.7, 3.3Hz, 1H, Ar-H), 6.68 (dd, J=9.0, 4.9Hz, 1H, Ar-H). 13 C NMR(151MHz,DMSO-d6)δ173.56,154.24,153.01(d, 1 J C-F =238.5Hz),146.96,144.55(d, 4 J C-F =4.6Hz),117.91(d, 2 J C-F =22.5Hz),116.97(d, 3 J C-F =8.3Hz),116.73(d, 2 J C-F =23.6Hz),115.24(d, 3 J C-F =7.5Hz); 19 F NMR(565MHz,DMSO-d6)δ-130.32.HRMS(ESI)[M+H] + calcd for C9H6N4FS:221.0292,found:221.0283.

[0051] (7) Preparation of intermediate 9-chloro-5H-[1,2,4]triazine[5,6-b]indole-3-thione:

[0052]

[0053] In a 250mL round-bottom flask, add compound 4-chloroindigo red (3.00g, 20mmol) and potassium carbonate (3.46g, 30mmol), add water and stir, then add thiosemicarbazide (1.52g, 20mmol), reflux and stir at 100℃, and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter and wash with a large amount of water. Dry to obtain the orange-red intermediate 9-chloro-5H-[1,2,4]triazine[5,6-b]indole-3-thione, with a yield of 25.90%. Its NMR data are: 1 H NMR (600MHz, DMSO-d6) δ7.60 (t, J = 7.9 Hz, 1H, Ar-H), 7.39 (t, J = 8.0 Hz, 2H, Ar-H). 13 C NMR(151MHz,DMSO-d6)δ179.65,149.60,144.82,135.25,133.17,128.79,123.98,116.18,112.25.HRMS(ESI)[M+H] + calcd for C9H6ClS:236.9996,found:236.9985.

[0054] (8) Preparation of target compound 1:

[0055]

[0056] In a 50 mL round-bottom flask, first add the intermediate (1) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (47.00 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (113.38 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 1 with a yield of 87.90%.

[0057] (9) Preparation of target compound 2:

[0058]

[0059] In a 50 mL round-bottom flask, first add the intermediate (1) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add propylthiol (57.64 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (113.38 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 2 with a yield of 90.14%.

[0060] (10) Preparation of target compound 3:

[0061]

[0062] In a 50 mL round-bottom flask, first add intermediate (1) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add propanethiol (109.98 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (113.38 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 3 with a yield of 92.67%.

[0063] (11) Preparation of target compound 31:

[0064]

[0065] In a 50 mL round-bottom flask, first add intermediate (2) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (43.97 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (106.03 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 31 with a yield of 75.45%.

[0066] (12) Preparation of target compound 32:

[0067]

[0068] In a 50 mL round-bottom flask, first add the intermediate (3) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (43.97 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (106.03 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 32 with a yield of 89.32%.

[0069] (13) Preparation of target compound 33:

[0070]

[0071] In a 50 mL round-bottom flask, first add the intermediate (4) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (43.18 mg, 1.5 mmol), stir at 0°C for 5 min, and finally slowly add DDQ (104.12 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 33, with a yield of 78.89%.

[0072] (14) Preparation of target compound 34:

[0073]

[0074] In a 50 mL round-bottom flask, first add the intermediate (5) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (43.18 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (104.12 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 34 with a yield of 88.65%.

[0075] (15) Preparation of target compound 35:

[0076]

[0077] In a 50 mL round-bottom flask, first add the intermediate (6) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (43.18 mg, 1.5 mmol), stir at 0°C for 5 min, finally slowly add DDQ (104.12 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 35 with a yield of 90.65%.

[0078] (16) Preparation of target compound 36:

[0079]

[0080] In a 50 mL round-bottom flask, first add the intermediate (7) (100.00 mg, 1 mmol), then add dichloromethane and stir, then add ethanethiol (40.18 mg, 1.5 mmol), stir at 0°C for 5 min, and finally slowly add DDQ (96.88 mg, 1 mmol), and track the reaction by TLC. After the reaction is completed, separate the solid and liquid, filter, and wash with a large amount of dichloromethane. Dry to obtain the light yellow target compound 36 with a yield of 56.78%.

[0081] The structure of the disulfide-containing compound synthesized above and its H NMR and C NMR data are shown in Table 1, and its physicochemical properties are shown in Table 2.

[0082] Table 1: H NMR, C NMR and high resolution mass spectrometry data of the compounds

[0083]

[0084]

[0085]

[0086]

[0087]

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098] Table 2: Physicochemical properties of target compounds

[0099]

[0100]

[0101] Example 2

[0102] EC 50Median effective concentration (MEC) is an important indicator for evaluating the sensitivity of plant pathogens to compounds. It is also an important parameter for setting compound concentration when studying the mechanism of action of target compounds. In the concentration gradient experiment, the two-fold dilution method was used to set 5 appropriate concentrations. Finally, the inhibition rate of the agent on plant pathogens and the concentration of the agent were converted into logarithmic values. The toxicity curve was obtained through regression analysis using SPSS software, and the EC was calculated. 50 .

[0103] The effective medium concentration EC of the target compound against plant pathogens was tested by turbidity method. 50 The test subjects were Xanthoceras oryzae (Xoo), Xanthoceras citri citri (Xac) and Psa. DMSO was dissolved in the culture medium as a blank control. Xanthoceras oryzae (Xac) was placed in NB culture medium, and cultured in a constant temperature shaker at 28°C and 180rpm until the logarithmic growth phase for later use; Xanthoceras citri citri (on M210 solid culture medium) was placed in NB culture medium; Psa oryzae spp. (on M210 solid culture medium) was placed in NB culture medium, and cultured in a constant temperature shaker at 28°C and 180rpm until the logarithmic growth phase for later use. 5 mL of toxic NB liquid medium containing different concentrations (e.g., 100, 50, 25, 1 2.5, 6.25 μg / mL) of the agent (compound) was added to the test tube, and 40 μL of NB liquid medium containing plant pathogenic bacteria was added respectively, and the mixture was shaken in a constant temperature shaker at 28-30°C and 180 rpm, wherein the rice bacterial leaf blight pathogen was cultured for 48 hours, the citrus canker pathogen was cultured for 48 hours, and the rice bacterial leaf streak pathogen was cultured for 36 hours. The OD595 value of the bacterial solution of each concentration was measured on an ELISA instrument, and the OD595 value of the toxic sterile NB liquid medium of the corresponding concentration was also measured.

[0104] Corrected OD value = OD value of bacterial culture medium - OD value of sterile culture medium

[0105] Inhibition rate % = [(corrected control culture medium bacterial solution OD value - corrected toxic culture medium OD value) / corrected control culture medium bacterial solution OD value] × 100

[0106] The examples of the present invention are used to illustrate the technical solutions of the present invention, but the contents of the examples are not limited thereto. The experimental results of the target compounds are shown in Table 3.

[0107] Table 3: EC values ​​of disulfide-substituted unsaturated nitrogen-containing heterocyclic compounds against plant pathogenic bacteria 50

[0108]

[0109]

[0110] As can be seen from Table 3, in the in vitro test, the target compounds showed good antibacterial activity against Xanthomonas oryzae and Xanthomonas oryzae. Compounds 1 and 33 showed excellent inhibitory activity against Xanthomonas oryzae (Xoo), with EC 50 The compound 1 showed excellent inhibitory activity against Xanthomonas axonopodis pv.citri (Xac), and its EC 50 It is 2.62μg / mL.

[0111] Example 3

[0112] Inhibitory activity of compounds against plant pathogenic fungi (50 μg / mL)

[0113] The mycelial growth rate method, also known as the toxic medium method, is one of the conventional methods for determining the toxicity of fungicides. The main principle is to mix the test agent with the culture medium, and measure the toxicity of the agent by the growth rate of the colonies on the toxic medium. In this example, Botrytis cinerea, Rhizoctonia solani, and Gibberella zeae were used as test objects, and DMSO was used as a blank control. The specific operation is as follows: 1) according to the test concentration, weigh an appropriate amount of drug, dissolve it with DMSO (the amount should not exceed 1% of the final poisonous medium), then add 0.1% Tween 20 solution to make the volume 10mL, pour into 90mL melted PDA medium, mix well and pour into 9 culture dishes for later use; 2) burn and sterilize the puncher (with an inner diameter of 5mm), after cooling, punch the hyphae at the edge of the pre-activated strain, and use an inoculation needle to stick its hyphae surface to the center of the poisonous medium, and after the treatment is completed, place it uniformly at 25°C for culture; 3) after the colony diameter of the control group grows to 5.5-6.6cm, the colony diameter of the control group and each drug treatment group is determined by the cross method; 4) the inhibition rate (%) is calculated using the following formula: inhibition rate % = (CT) / (C-0.5) × 100; wherein C is the colony diameter of the control group, T is the colony diameter of the drug treatment group, and 0.5 is the diameter of the inoculated cake. According to the above method, the experimental results of the target compounds in Table 1 are shown in Table 4.

[0114] Table 4: Inhibitory activity of compounds against plant pathogenic fungi (50 μg / mL)

[0115]

[0116] In summary, it can be seen from Table 3 that in the in vitro test, the target compounds showed good inhibitory activity against plant pathogenic bacteria such as Xanthoceras oryzae. Among them, most compounds containing ethyl in their structures had an EC of 1. 50 All of them were within 10, especially the EC value of compound 1 against Xanthomonas oryzae 50 The EC value of compound 16 against Xanthomonas citri ulcerans was 0.77 μg / mL. 50 The EC value of compound 6 against kiwifruit canker pathogen was 3.43 μg / mL. 50 It is 2.86 μg / mL. As can be seen from Table 4, the target compounds also show certain inhibitory activity against plant pathogenic fungi. At a concentration of 50 μg / mL, all target compounds have good biological activity against Rhizoctonia solani. Among them, compound 33 has excellent inhibitory activity against Rhizoctonia solani, Botrytis cinerea and Gibberella fusca, with inhibition rates of 92.35%, 75.81% and 61.33%, respectively. Therefore, it can be seen that this type of compound can be used as a new type of pesticide against plant pathogenic bacteria and fungi, and has extremely high research value.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention. The scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A class of 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure, characterized in that : The compound has a structure as shown in the general formula (I): Wherein, R1 is selected from any substituted or unsubstituted alkyl, any substituted or unsubstituted cycloalkyl and any substituted or unsubstituted aryl or benzyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

2. The 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure according to claim 1, characterized in that: R1 is selected from C2-C8 alkyl, substituted or unsubstituted C6-C7 aryl, substituted or unsubstituted benzyl, wherein the substitution refers to one or more substitutions by halogen, methyl, methoxy, trifluoromethyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

3. The 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure according to claim 2, characterized in that: R1 is selected from ethyl, propyl, allyl, n-butyl, n-hexyl, n-heptyl, octyl, decanyl, dodecyl, substituted or unsubstituted phenyl, substituted or unsubstituted benzyl, wherein the substitution refers to one or more substitutions selected from methyl, methoxy, halogen, trifluoromethyl; R2 is selected from methyl; R3 is selected from methyl or fluorine; R4, R5 and R6 are each independently selected from fluorine or chlorine.

4. The 5H-[1,2,4]triazine[5,6-b]indole derivatives containing a disulfide structure according to claim 3, characterized in that: Includes the following compounds:

5. The method for preparing the 5H-[1,2,4]triazine[5,6-b]indole derivative containing a disulfide structure according to any one of claims 1 to 4, characterized in that: The preparation method comprises the following steps:

6. A composition characterized in that Contains the compound according to any one of claims 1 to 4, and an adjuvant or fungicide for agricultural use.

7. Use of the compound according to any one of claims 1 to 4, or the composition according to claim 6, in the preparation of a medicament for preventing and controlling plant bacterial diseases.

8. The use according to claim 7, characterized in that :The agricultural pests and diseases are plant bacterial diseases.

9. The use according to claim 7, characterized in that :The agricultural pests and diseases are plant leaf blight and plant canker.

10. The use according to claim 7, characterized in that :The agricultural pests and diseases are any one of rice bacterial blight, citrus canker, and kiwi fruit canker.

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