Pyridine type coumarin derivative as well as preparation method and application thereof

Abstract

The invention discloses a pyridine type coumarin derivative as well as a preparation method and application thereof. The pyridine type coumarin derivative disclosed by the invention is selected from a compound shown in the following structural general formula: # imgabs0 #. The novel pyridine type coumarin derivative is independently designed and synthesized; experimental results show that the pyridine type coumarin derivative has good antifungal activity on botrytis cinerea, alternaria solani, fusarium oxysporum and alternaria alternata, a new field is expanded for prevention and treatment of various plant fungal diseases, and the pyridine type coumarin derivative has wide development space, good development and application prospects and good application value.

Description

Technical Field

[0001] The present invention relates to the technical field of synthesis of coumarin derivatives, and more particularly to pyridine coumarin derivatives and preparation methods and applications thereof. Background Art

[0002] Plant pathogenic fungi are destructive parasites that secrete a large number of toxins and harmful metabolites, which can directly or indirectly lead to significant reductions in plant yield and quality. Therefore, the management of plant fungal diseases is crucial in agricultural production. In the past few decades, traditional chemical fungicides have been widely used to reduce the damage caused by plant pathogenic fungi. Unfortunately, many chemical fungicides are not only toxic to humans, but also to insects and microorganisms that are beneficial to plant growth. Therefore, the long-term use of traditional fungicides in agriculture has led to many problems, such as negative impacts on the environment due to slow degradation, harmful effects on non-target species, and fungicide resistance.

[0003] Therefore, the discovery and development of new, eco-friendly, and highly effective agricultural fungicides with novel mechanisms of action is an urgent research focus in this field. Natural products have always been a rich source for pesticide development because of their structural diversity and eco-friendly nature. Many natural products have been isolated from plants or microorganisms and have inspired the discovery of new fungicides. Natural products are secondary metabolites produced by plants that have good biocompatibility and biodegradability. In addition, they have the characteristics of structural diversity, good biological activity, and environmental compatibility. For these reasons, natural products have always been powerful raw materials in the discovery of pharmaceuticals and agrochemicals. In fact, the use of natural plant-derived products is an effective way to develop green and efficient fungicides.

[0004] Coumarin is a natural product. Due to its pharmacological diversity, it has anticoagulant, anticancer, antioxidant, antiviral, anti-inflammatory and antifungal effects. It has been recognized as a "privileged scaffold" for the application of phytomedicine and agrochemicals. As typical coumarin derivatives, the biological activities of warfarin and Cnidium monnieri have been reported in detail. Coumarin with structural diversity can be considered as an important candidate for the development of highly effective fungicides. Pyridine heterocycles are widely used as active groups in the structural optimization of agrochemical related compounds. Pyridine is a commonly used fungicide. Its mechanism of action is to destroy the cell membrane and cell wall of bacteria, thereby causing bacterial death. Pyridine can kill a variety of common pathogens and fungi, such as rot bacteria, Fusarium oxysporum, gray mold, black spot bacteria, etc., and has a significant effect on plant health.

[0005] Further modification of existing coumarin and pyridine compounds to improve the above-mentioned related properties. Summary of the invention

[0006] In order to solve the problems in the prior art, the present invention proposes pyridine coumarin derivatives and preparation methods and applications thereof. The present invention designs and synthesizes coumarin derivatives with new substituents, and preliminarily studies their inhibitory effects on four plant pathogens, namely, Botrytis cinerea, Alternaria solanacearum, Fusarium oxysporum and Alternaria alternata. The experimental results of the present invention show that the pyridine coumarin derivatives of the present invention have significant inhibitory effects on fungi and have significant effects on plant health care.

[0007] One of the purposes of the present invention is to provide a pyridine coumarin derivative, wherein the pyridine coumarin derivative is selected from the compounds represented by the following general structural formula:

[0008]

[0009] Wherein, R1, R2, and R3 are the same or different and are independently selected from Among them, R a is selected from alkenyl, substituted or unsubstituted aryl; and only one of the substituents appears at the same time in OR1, OR2, and OR3. The --- bond of the present invention means that the substituent connected by the bond may exist or not.

[0010] Among the pyridine coumarin derivatives of the present invention, preferably, the pyridine coumarin derivatives are selected from the compounds represented by the following general structural formula:

[0011]

[0012] Wherein, R1 in Formula 1 is selected from R 1a is selected from alkenyl, substituted or unsubstituted thienyl, substituted or unsubstituted phenyl;

[0013] Preferably, R 1a A phenyl group substituted with at least one substituent selected from C2-C8 alkenyl; halogen-substituted thienyl, thienyl; halogen, C1-C4 alkyl, fluoroalkyl;

[0014] More preferably, R 1a is selected from a C3-C8 alkenyl, a phenyl substituted by a halogen and a C1-C2 alkyl, a phenyl substituted by a fluoroalkyl, a phenyl substituted by a fluoroalkyl and a halogen, a thienyl substituted by a halogen, and a thienyl;

[0015] More preferably, the formula 1 is selected from the following compounds:

[0016]

[0017] Among the pyridine coumarin derivatives of the present invention, preferably, the pyridine coumarin derivatives are selected from the following structural formulas:

[0018]

[0019] R2 in Formula 2 is selected from Among them, R 2a is selected from substituted or unsubstituted thienyl

[0020] Preferably, R 2a is selected from halogen-substituted thienyl, thienyl;

[0021] More preferably, R 2a is selected from a halogen-substituted thienyl, thienyl;

[0022] More preferably, the formula 2 is selected from the following compounds:

[0023]

[0024] Among the pyridine coumarin derivatives of the present invention, preferably, the pyridine coumarin derivatives are selected from the following structural formulas:

[0025]

[0026] R3 in Formula 3 is selected from Among them, R 3a is selected from alkenyl, substituted or unsubstituted thienyl, substituted or unsubstituted phenyl;

[0027] Preferably, R 3a A phenyl group substituted with at least one substituent selected from C2-C8 alkenyl; halogen-substituted thienyl, thienyl; halogen, C1-C4 alkyl, fluoroalkyl;

[0028] More preferably, R 3a A phenyl group selected from the group consisting of a C3-C8 alkenyl group, a phenyl group substituted by a halogen and a C1-C2 alkyl group, a phenyl group substituted by a fluoroalkyl group, a phenyl group substituted by a fluoroalkyl group and a halogen, a thienyl group substituted by a halogen, and a thienyl group;

[0029] More preferably, the formula 3 is selected from the following compounds:

[0030]

[0031] The second object of the present invention is to provide a method for preparing pyridine coumarin derivatives, comprising the following steps:

[0032] reacting substrate 1 with substrate 2, a condensing agent, and a basic catalyst in a solvent to obtain the pyridine-type pyridine-type coumarin derivative;

[0033] Wherein, substrate 1 is selected from the following structural formula:

[0034]

[0035] Among them, only one of the three hydroxyl groups in formula B exists at the same time;

[0036] Substrate 2 is selected from At least one of R a R according to any one of the objects of the present invention a The corresponding same.

[0037] In the method for preparing pyridine coumarin derivatives of the present invention, preferably,

[0038] The substrate 1 is selected from one of the following compounds:

[0039]

[0040] Substrate 2 is selected from At least one of R 1a , R 2a , R 3a R according to any one of the objects of the present invention 1a , R 2a , R 3a The corresponding same.

[0041] In the method for preparing pyridine coumarin derivatives of the present invention, preferably,

[0042] The condensing agent is selected from at least one of EDC (1-ethyl-3-(3-dimethylaminopropyl) carbodiimide) or DCC (N,N-dicyclohexylcarbodiimide); and / or,

[0043] The alkaline catalyst is selected from at least one of 4-dimethylaminopyridine (DMAP) and 1-hydroxybenzotriazole (HOBT); and / or,

[0044] The solvent is selected from at least one of dichloromethane or a mixture of petroleum ether and ethyl acetate; preferably, in the mixture of petroleum ether and ethyl acetate, the volume ratio of petroleum ether to ethyl acetate is 15-10:1.

[0045] In the method for preparing pyridine coumarin derivatives of the present invention, preferably,

[0046] The molar ratio of substrate 2 to substrate 1 is (2-4):1; for example, 2:1, 3:1, 4:1; and / or,

[0047] The molar ratio of the condensing agent to the substrate 1 is (3-6):1; for example: 3:1, 4:1, 5:1, 6:1; and / or,

[0048] The molar ratio of the condensing agent to the alkaline catalyst is (5-8):1; for example, 5:1, 6:1, 7:1, 8:1; and / or,

[0049] The mass volume ratio of the condensing agent to the solvent is (2-20) mg:1 mL; for example, 2 mg:1 mL, 5 mg:1 mL, 10 mg:1 mL, 15 mg:1 mL, 20 mg:1 mL; and / or,

[0050] The reaction time is 6-10 hours; for example, 6, 7, 8, 9, 10 hours.

[0051] The third object of the present invention is to provide a use of the pyridine coumarin derivatives as described in one of the objects of the present invention in at least one of antifungal, antiviral, anti-inflammatory or antitumor applications.

[0052] In the application described herein, preferably, the pyridine coumarin derivative is used to inhibit at least one fungus selected from Botrytis cinerea, Alternaria solani, Fusarium oxysporum or Alternaria alternata.

[0053] The substances and parameters not limited in the present invention can be selected according to the existing technology and belong to the conventional technical means in this field.

[0054] The endpoints and any values ​​of the scope disclosed in the present invention are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, the endpoint values ​​of each scope, the endpoint values ​​of each scope and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be regarded as specifically disclosed in this article.

[0055] Compared with the prior art, the present invention has at least the following advantages:

[0056] The pyridine coumarin derivatives of the present invention have good application value in resisting plant-derived fungi. In particular, the fungi targeted are Botrytis cinerea, which causes gray mold of strawberries and tomatoes, Altemaria solani, which causes early blight of tomatoes, Fusarium oxysporum, which causes crop wilt, and Alternaria alternata, which causes black mold of tomatoes. The fungicidal effects are good inhibitory activity against four common basic fungi of plants, and can be used as lead compounds for creating new agricultural fungicides for the treatment or prevention of plant fungal infectious diseases. Therefore, the pyridine coumarin derivatives of the present invention can be used in the preparation of antifungal drugs, especially in the preparation of antifungal botanical drugs. DETAILED DESCRIPTION

[0057] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0058] It should also be noted that the various specific technical features described in the following specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0059] In addition, the various embodiments of the present invention may be arbitrarily combined as long as they do not violate the concept of the present invention. The technical solutions thus formed belong to part of the original disclosure of this specification and also fall within the protection scope of the present invention.

[0060] The raw materials used in the examples and comparative examples, unless otherwise specified, are disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0061] Example 1

[0062] Synthesis of compound 1a

[0063]

[0064] 3-Chloro-4-methylbenzoic acid (102.4 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 1 (this compound 1 is the same substance as compound 1 in the specification of the present invention) (58.7 mg, 1 mmol) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1a.

[0065] Example 2

[0066] Synthesis of compound 1b

[0067]

[0068] 2-Trifluoromethylbenzoic acid (114.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1b.

[0069] Example 3

[0070] Synthesis of compound 1c

[0071]

[0072] 4-Trifluoromethylbenzoic acid (114.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1c.

[0073] Example 4

[0074] Synthesis of compound 1d

[0075]

[0076] 3-Bromo-4-trifluoromethylbenzoic acid (161.5 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1d.

[0077] Example 5

[0078] Synthesis of compound 1e

[0079]

[0080] (E)-2-methyl-2-butenoic acid (60.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 1 (58.7 mg, 1 mmol) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1e.

[0081] Example 6

[0082] Synthesis of compound 1f

[0083]

[0084] 3-Bromothiophene-2-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1f.

[0085] Example 7

[0086] Synthesis of compound 1g

[0087]

[0088] 3-Chlorothiophene-2-carboxylic acid (97.6 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain 1 g of the target compound.

[0089] Example 8

[0090] Synthesis of compound 1h

[0091]

[0092] 5-Bromothiophene-3-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 1 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1h.

[0093] Example 9

[0094] Synthesis of compound 1i

[0095]

[0096] 3-Thiophenecarboxylic acid (77.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 1 (58.7 mg, 1 mmol) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 1i.

[0097] Example 10

[0098] Synthesis of compound 2a

[0099]

[0100] 3-Bromothiophene-2-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 2 (58.7 mg, 1 mmol) (compound 2 here has the same structure as compound 2 of the present invention) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 2a.

[0101] Embodiment 11

[0102] Synthesis of compound 2b

[0103]

[0104] 3-Chlorothiophene-2-carboxylic acid (97.6 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 2 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 2b.

[0105] Example 12

[0106] Synthesis of compound 2c

[0107]

[0108] 5-Bromothiophene-3-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 2 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 2c.

[0109] Embodiment 13

[0110] Synthesis of compound 2d

[0111]

[0112] 3-Thiophenecarboxylic acid (77.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 2 (58.7 mg, 1 mmol) was weighed and added to the reaction bottle and stirred at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 2d.

[0113] Embodiment 14

[0114] Synthesis of compound 3a

[0115]

[0116] 3-Chloro-4-methylbenzoic acid (102.4 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 3 (58.7 mg, 1 mmol) (compound 3 here has the same structure as compound 3 of the present invention) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3a.

[0117] Embodiment 15

[0118] Synthesis of compound 3b

[0119]

[0120] 2-Trifluoromethylbenzoic acid (114.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 3 (58.7 mg, 1 mmol) was weighed and added to the reaction bottle and stirred at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3b.

[0121] Example 16

[0122] Synthesis of compound 3c

[0123]

[0124] Weigh p-bromo-o-methylbenzoic acid (129.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) into a 50 mL round-bottom flask, add dichloromethane (20 mL) and stir at room temperature for 20 min. Then weigh compound 3 (58.7 mg, 1 mmol) and add it into the reaction bottle, stir and react at 25°C for 6 h, and monitor the reaction by TLC. After the reaction is completed, evaporate the reaction solution under reduced pressure, and purify the crude product by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3c.

[0125] Embodiment 17

[0126] Synthesis of compound 3d

[0127]

[0128] 3-Bromo-4-trifluoromethylbenzoic acid (161.5 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 3 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3d.

[0129] Embodiment 18

[0130] Synthesis of compound 3e

[0131]

[0132] (E)-2-methyl-2-butenoic acid (60.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 3 (58.7 mg, 1 mmol) was weighed and added to the reaction bottle, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3e.

[0133] Embodiment 19

[0134] Synthesis of compound 3f

[0135]

[0136] (E)-2-methyl-2-pentenoic acid (68.5 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Then compound 3 (58.7 mg, 1 mmol) was weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3f.

[0137] Embodiment 20

[0138] Synthesis of compound 3g

[0139]

[0140] 3-Bromothiophene-2-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 3 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain 3 g of the target compound.

[0141] Embodiment 21

[0142] Synthesis of compound 3h

[0143]

[0144] 3-Chlorothiophene-2-carboxylic acid (97.6 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 3 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3h.

[0145] Embodiment 22

[0146] Synthesis of compound 3i

[0147]

[0148] 5-Bromothiophene-3-carboxylic acid (124.2 mg, 3.00 mmol), EDC (93.0 mg g, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 3 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25 ° C for 6 h, and the reaction was detected by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3i.

[0149] Embodiment 23

[0150] Synthesis of compound 3j

[0151]

[0152] 3-Thiophenecarboxylic acid (77.0 mg, 3.00 mmol), EDC (93.0 mg, 3.00 mmol) and DMAP (9.8 mg, 0.4 mmol) were weighed and added to a 50 mL round-bottom flask, and dichloromethane (20 mL) was added and stirred at room temperature for 20 min. Compound 3 (58.7 mg, 1 mmol) was then weighed and added to the reaction flask, stirred and reacted at 25°C for 6 h, and the reaction was monitored by TLC. After the reaction was completed, the reaction solution was evaporated under reduced pressure, and the crude product was purified by silica gel column chromatography (eluent: petroleum ether / ethyl acetate = 15-10 / 1, V / V) to obtain the target compound 3j.

[0153] The structural characterization results of the target compounds prepared in the above Examples 1-23 are as follows:

[0154] 1. Compound 1a

[0155]

[0156] White solid, yield 50.6%. 1 H NMR (600MHz, CDCl3) δ8.55(dd,J=7.9,1.7Hz,1H),8.24(d,J=1.8Hz,1H),8.05(dd,J=7.9,1.8Hz,1H),7.45(dd,J =7.9,1.6Hz,1H),7.40(t,J=7.9Hz,2H),4.48(q,J=7.1Hz,2H),2.77(s,3H),2.70(s,3H),1.44(t,J=7.1Hz,4H).

[0157] 13 C NMR (150MHz, CDCl3) δ168.07,163.55,160.93,158.99,152.14,150.18,144.85,142.89,137.94,135.00,132.17 ,131.31,131.16,128.81,128.03,125.85,124.37,123.35,120.81,114.03,62.25,23.94,20.69,19.55,14.32.

[0158] 2. Compound 1b

[0159]

[0160] White solid, yield 56.8%. 1 H NMR (600MHz, CDCl3) δ8.56(dd,J=8.0,1.5Hz,1H),8.22(d,J=8.8Hz,1H),7.86(d,J=7.6Hz,1H ),7.78–7.70(m,2H),4.49(q,J=7.1Hz,2H),2.79(s,3H),2.70(s,3H),1.44(t,J=7.2Hz,3H).

[0161] 13 C NMR (150MHz, CDCl3) δ168.06,164.37,161.00,158.93,152.12,150.21,144.76,137.59,132.21,131.26,12 9.60(d,J=18.5Hz),127.08,125.58,124.47,123.63,122.55,120.84,114.08,62.27,23.95,19.56,14.32.

[0162] 3. Compound 1c

[0163]

[0164] Pale yellow solid, yield 33.4%. 1H NMR (600MHz, CDCl3) δ8.57(dd,J=8.0,1.6Hz,1H),8.40(d,J=8.0Hz,2H),7.82(d,J=8.1Hz,2H),7.47(dd,J=7 .9,1.6Hz,1H),7.42(t,J=7.9Hz,1H),4.49(q,J=7.1Hz,2H),2.77(s,3H),2.70(s,3H),1.44(t,J=7.1Hz,3H).

[0165] 13 C NMR (150MHz, CDCl3) δ168.04,163.43,161.02,158.93,152.08,150.22,144.73,137.77,135.57,135.36,132. 19(d,J=19.1Hz),131.09,125.78(d,J=21.8Hz),124.41,123.57,120.90,114.04,62.28,23.94,19.55,14.32.

[0166] 4. Compound 1d

[0167]

[0168] White solid, yield 32.3%. 1 H NMR (600MHz, CDCl3) δ8.70(d,J=8.5Hz,1H),8.55(d,J=1.8Hz,1H),8.24(s,1H),7.87(d,J=8.3Hz ,1H),7.29–7.23(m,2H),4.49(q,J=7.2Hz,2H),2.81(s,3H),2.70(s,3H),1.45(t,J=7.2Hz,3H).

[0169] 13 C NMR (150MHz, CDCl3) δ168.07, 162.34, 161.05, 159.95, 153.30 (d, J = 6.0Hz), 151.86, 150.23, 136.56, 135.05, 133. 50,132.07,129.09,128.38,127.13,121.62,120.76,118.34,117.58,113.68,110.15,62.29,23.95,19.55,14.33.

[0170] 5. Compound 1e

[0171]

[0172] White solid, yield 47.3%. 1 H NMR (600MHz, CDCl3) δ8.64–8.59(m,1H),7.19–7.12(m,3H),4.48(q,J=7.1Hz,2H),2.79(s ,3H),2.68(s,3H),1.99–1.96(m,3H),1.91(dd,J=7.1,1.3Hz,3H),1.44(t,J=7.1Hz,3H).

[0173] 13 C NMR (150MHz, CDCl3) δ168.17,165.96,160.89,160.18,154.39,153.25,152.14,150.13,140.69,13 1.78,127.91,126.70,118.81,116.75,113.47,110.25,62.21,23.93,19.54,14.91,14.32,12.32.

[0174] 6. Compound 1f

[0175]

[0176] Yellow solid, yield 26.5%. 1 H NMR (600MHz, CDCl3) δ8.55(dd,J=8.0,1.7Hz,1H),7.63(d,J=5.7Hz,1H),7.47(dd,J=7.9,1.7Hz,1H),7.39(t ,J=8.0Hz,1H),7.21(d,J=5.3Hz,1H),4.48(q,J=7.1Hz,2H),2.77(s,3H),2.70(s,3H),1.44(t,J=7.1Hz,3H).

[0177] 13 C NMR (150MHz, CDCl3) δ168.05,160.93,158.94,152.08,150.24,137.35,133.54,133.07 ,132.21,126.00,124.31,123.55,120.78,119.80,114.09,62.25,23.91,19.55,14.32.

[0178] 7. Compound 1g

[0179]

[0180] White solid, yield 33.4%. 1 H NMR (600MHz, CDCl3) δ8.55(dd,J=8.0,1.6Hz,1H),7.64(d,J=5.3Hz,1H),7.47(dd,J=7.9,1.6Hz,1 H),7.39(t,J=7.9Hz,1H),4.49(q,J=7.1Hz,2H),2.77(s,3H),2.69(s,3H),1.44(t,J=7.2Hz,3H).

[0181] 13 C NMR (150MHz, CDCl3) δ168.08,160.94,158.96,158.21,152.09,150.19,144.89,137.32,134.21 ,132.18,130.71,125.97,124.31,124.02,123.52,120.79,114.06,62.25,23.94,19.55,14.32.

[0182] 8. Compound 1h

[0183]

[0184] White solid, yield 75.1%. 1 H NMR (600MHz, CDCl3) δ8.54(dd,J=7.8,1.9Hz,1H),8.29(d,J=1.6Hz,1H),7.67(d,J=1.5Hz,1H ),7.46–7.36(m,2H),4.48(q,J=7.1Hz,2H),2.77(s,3H),2.69(s,3H),1.44(t,J=7.1Hz,3H).

[0185] 13 C NMR (150MHz, CDCl3) δ168.04, 160.96, 159.06 (d, J = 14.5Hz), 152.12, 150.20, 144.81, 137.61 (d, J = 1.9Hz), 136. 18,132.27(d,J=11.8Hz),130.79,125.79,124.35,123.41,120.83,114.04,113.66,62.25,23.95,19.55,14.32.

[0186] 9. Compound 1i

[0187]

[0188] White solid, yield 66.4%. 1 H NMR (600MHz, CDCl3) δ8.54(dd,J=7.9,1.8Hz,1H),8.41(d,J=3.1Hz,1H),7.72(d,J=5.1Hz,1H ),7.49–7.31(m,3H),4.48(q,J=7.1Hz,2H),2.77(s,3H),2.70(s,3H),1.44(t,J=7.1Hz,3H).

[0189] 13 C NMR (150MHz, CDCl3) δ168.08,160.91,160.30,159.08,152.19,150.18,144.95,137.86,135.01,132 .15,132.03,128.57,126.61,125.97,124.34,123.24,120.78,114.04,62.24,23.94,19.54,14.31.

[0190] 10. Compound 2a

[0191]

[0192] White solid, yield 45.7%. 1 H NMR (600MHz, CDCl3) δ8.68–8.64(m,1H),7.63(d,J=5.3Hz,1H),7.31–7.27(m,2H),7.21( d,J=5.3Hz,1H),4.49(q,J=7.1Hz,2H),2.80(s,3H),2.69(s,3H),1.44(t,J=7.1Hz,3H).

[0193] 13 C NMR (150MHz, CDCl3) δ168.12,160.97,160.04,158.52,153.22,151.98,150.19,133.67,133.05 ,131.95,126.87,126.06,119.64,118.58,117.28,113.62,110.22,62.24,23.94,19.55,14.33.

[0194] 11. Compound 2b

[0195]

[0196] Pale yellow solid, yield 46.5%. 1 H NMR (600MHz, CDCl3) δ8.68–8.64(m,1H),7.63(d,J=5.3Hz,1H),7.30–7.25(m,2H),7.13( d,J=5.3Hz,1H),4.49(q,J=7.2Hz,2H),2.80(s,3H),2.69(s,3H),1.44(t,J=7.2Hz,3H).

[0197] 13 C NMR (150MHz, CDCl3) δ168.12,160.96,160.04,158.33,153.22,151.98,150.18,134.06,132.18 ,131.94,130.83,126.86,124.32,118.58,117.27,113.61,110.22,62.24,23.93,19.55,14.32.

[0198] 12. Compound 2c

[0199]

[0200] White solid, yield 55.7%. 1 H NMR (600MHz, CDCl3) δ8.68–8.64(m,1H),8.24(d,J=1.5Hz,1H),7.64(d,J=1.5Hz,1H),7. 24–7.20(m,2H),4.49(q,J=7.2Hz,2H),2.80(s,3H),2.69(s,3H),1.44(t,J=7.1Hz,3H).

[0201] 13 C NMR (150MHz, CDCl3) δ168.11,160.98,160.04,159.27,153.49,153.25,151.98,150.18,135.96,132 .62,131.94,130.56,126.94,118.53,117.22,113.81,113.58,110.18,62.25,23.94,19.54,14.33.

[0202] 13. Compound 2d

[0203]

[0204] White solid, yield 35.7%. 1H NMR (600MHz, CDCl3) δ8.68–8.64(m,1H),8.36(dd,J=3.1,1.3Hz,1H),7.68(dd,J=5.1,1.2Hz,1H),7.42(dd,J =5.1,3.0Hz,1H),7.27–7.22(m,2H),4.49(q,J=7.1Hz,2H),2.80(s,3H),2.69(s,3H),1.44(t,J=7.1Hz,3H).

[0205] 13 C NMR (150MHz, CDCl3) δ168.15,160.94,160.46,160.12,153.75,153.24,152.04,150.16,134.82,132.2 8,131.86,128.34,126.83(d,J=6.5Hz),118.72,117.05,113.52,110.29,62.25,23.95,19.58,14.33.

[0206] 14. Compound 3a

[0207]

[0208] White solid, yield 25.7%. 1 H NMR (600MHz, CDCl3) δ8.55(dd,J=7.9,1.8Hz,1H),8.24(d,J=1.9Hz,1H),8.05(dd,J=7.9,1.9Hz ,1H),7.48–7.35(m,3H),4.48(q,J=7.1Hz,2H),2.77(s,3H),2.70(s,3H),1.44(t,J=7.1Hz,3H).

[0209] 13 C NMR (150MHz, CDCl3) δ168.04,163.54,160.92,158.97,152.12,150.24,144.86,142.88,137.96,135.00,132.20,1 31.23(d,J=13.0Hz),128.82,128.05,125.87,124.38,123.37,120.78,114.05,62.25,23.91,19.54,18.57,14.31.

[0210] 15. Compound 3b

[0211]

[0212] White solid, yield 25.6%. 1 H NMR(600MHz, CDCl3)δ8.48(d,J=2.7Hz,1H),8.07–8.03(m,1H),7.89–7.84(m,1H),7.76–7.69(m ,2H),7.48–7.39(m,2H),4.49(q,J=7.2Hz,2H),2.82(s,3H),2.69(s,3H),1.44(t,J=7.2Hz,3H).

[0213] 13 C NMR (150MHz, CDCl3) δ168.06,165.29,160.96,160.00,151.75,150.55,150.18,147.13,132.35,132.2 0,130.99,130.08,127.18(d,J=5.4Hz),125.85,120.24,118.15,113.98,62.29,23.88,19.57,14.32.

[0214] 16. Compound 3c

[0215]

[0216] White solid, yield 65.7%. 1 H NMR (600MHz, CDCl3) δ8.44–8.41(m,1H),8.08(d,J=8.4Hz,1H),7.53–7.47(m,2H),7.40( d,J=1.3Hz,2H),4.49(q,J=7.1Hz,2H),2.81(s,3H),2.67(s,6H),1.44(t,J=7.2Hz,3H).

[0217] 13 C NMR (150MHz, CDCl3) δ168.05,165.17,160.89,160.00,151.80,150.37,150.20,147.29,143.84,135.11,132.87 ,132.31,129.43,128.10,127.01,126.32,120.20,118.42,117.99,113.98,62.28,23.86,22.02,19.56,14.32.

[0218] 17. Compound 3d

[0219]

[0220] White solid, yield 23.7%. 1 H NMR (600MHz, CDCl3) δ8.56(d,J=1.8Hz,1H),8.46(dd,J=2.0,1.4Hz,1H),8.25(s,1H),7.87(d,J=8. 3Hz,1H),7.44–7.41(m,2H),4.49(q,J=7.1Hz,2H),2.82(s,3H),2.67(s,3H),1.44(t,J=7.1Hz,3H).

[0221] 13 C NMR (150MHz, CDCl3) δ168.00,162.97,160.98,159.90,151.66,150.61,150.26,146.99,136.51,133.73 ,132.44,129.02,128.35,125.85,123.46,120.71,120.35,118.24,114.06,62.31,23.87,19.55,14.32.

[0222] 18. Compound 3e

[0223]

[0224] Pale yellow solid, yield 35.7%. 1 H NMR (600MHz, CDCl3) δ8.33(d,J=2.8Hz,1H),7.35(d,J=8.8Hz,1H),7.31(dd,J=8.9,2.8Hz,1H),7.17(d,J=8.4,7.1,5.7,1.5H z,1H),4.48(q,J=7.1Hz,2H),2.80(s,3H),2.66(s,3H),2.00–1.97(m,3H),1.91(dd,J=7.1,1.2Hz,3H),1.44(t,J=7.2Hz,3H).

[0225] 13 C NMR (150MHz, CDCl3) δ168.10,166.67,160.81,160.11,151.93,150.13,147.77,140.21,132.1 8,128.04,126.37,120.03,118.37,117.79,113.91,62.24,23.84,19.55,14.87,14.31,12.33.

[0226] 19. Compound 3f

[0227]

[0228] White solid, yield 33.5%. 1 H NMR (600MHz, CDCl3) δ8.34(d,J=2.6Hz,1H),7.38–7.29(m,2H),7.06(td,J=7.4,1.5Hz,1H),4.48(q,J=7.1Hz,2H),2.80(s, 3H), 2.66 (s, 3H), 2.34–2.18 (m, 4H), 1.97 (d, J = 1.4Hz, 3H), 1.88 (d, J = 1.5Hz, 2H), 1.44 (t, J = 7.2Hz, 3H), 1.15–1.03 (m, 6H).

[0229] 13 C NMR (150MHz, CDCl3) δ168.13,166.87,160.81,160.14,151.95,150.15,148.58,147.79,146.96,132.1 9,127.21,126.40,120.04,118.39,117.81,113.93,62.26,23.86,22.48,19.58,14.32,13.12,12.51.

[0230] 20. Compound 3g

[0231]

[0232] White solid, yield 23.5%. 1 H NMR (600MHz, CDCl3) δ8.47(d,J=2.7Hz,1H),7.62(d,J=5.3Hz,1H),7.46–7.37( m,2H),4.49(q,J=7.1Hz,2H),2.81(s,3H),2.67(s,3H),1.44(t,J=7.1Hz,3H).

[0233] 13 C NMR (150MHz, CDCl3) δ168.06,160.92,160.00,159.23,151.78,150.48,150.18,146.80,133.59,132.8 4,132.33,126.20(d,J=10.4Hz),120.17,119.37,118.47,117.95,114.00,62.28,23.86,19.56,14.32.

[0234] 21. Compound 3h

[0235]

[0236] White solid, yield 24.8%. 1 H NMR (600MHz, CDCl3) δ8.47(d,J=2.5Hz,1H),7.63(d,J=5.4Hz,1H),7.46–7.37( m,2H),4.49(q,J=7.2Hz,2H),2.81(s,3H),2.67(s,3H),1.44(t,J=7.1Hz,3H).

[0237] 13 C NMR (150MHz, CDCl3) δ168.06,160.92,160.00,159.05,151.78,150.47,150.18,146.79,133.80,132 .32,131.96,130.76,126.16,124.51,120.16,118.47,117.95,113.99,62.27,23.85,19.55,14.32.

[0238] 22. Compound 3i

[0239]

[0240] White solid, yield 73.5%. 1 H NMR (600MHz, CDCl3) δ8.42(t,J=1.7Hz,1H),8.24(d,J=1.5Hz,1H),7.65(d,J=1.5Hz,1H),7. 39(d,J=1.6Hz,2H),4.49(q,J=7.2Hz,2H),2.81(s,3H),2.67(s,3H),1.44(t,J=7.1Hz,3H).

[0241] 13 C NMR (150MHz, CDCl3) δ168.06,160.92,160.01,151.78,150.42,150.20,147.06,135.69,132.86 ,132.33,130.59,126.09,120.21,118.34,118.01,113.99,113.71,62.29,23.86,19.55,14.32.

[0242] 23. Compound 3j

[0243]

[0244] White solid, yield 73.5%. 1 H NMR (600MHz, CDCl3) δ8.44 (dd, J=2.6, 0.7Hz, 1H), 8.36 (dd, J=3.1, 1.2Hz, 1H), 7.69 (dd, J=5.1, 1.2 Hz,1H),7.44–7.37(m,3H),4.49(q,J=7.2Hz,2H),2.81(s,3H),2.66(s,3H),1.44(t,J=7.1Hz,3H).

[0245] 13 C NMR (150MHz, CDCl3) δ168.08,161.18,160.88,160.06,151.86,150.34,150.17,147.28,134.53,132 .57,132.27,128.35,126.71,126.27,120.16,118.44,117.93,113.97,62.26,23.86,19.55,14.32.

[0246] Comparative Example 1

[0247] The preparation method is basically the same as that of Example 2, except that the substrate 2 used is The structure of the compound prepared by the above method is: Embodiment 24

[0248] Performance Test:

[0249] First, a preliminary in vitro antibacterial activity test was conducted on the 23 synthesized compounds. The test bacteria and experimental process are as follows:

[0250] 1. Test bacteria used in the experiment

[0251] Table 1

[0252]

[0253] The above four standard strains were used in this part of the experiment. The strains were provided by the Chemical Ecology Laboratory of the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, and can also be purchased directly through Gary Chemical Network, Shanghai Bo Ke Biotechnology Co., Ltd., etc.

[0254] 2. Preparation of PDA medium

[0255] (1) Weighing and boiling: Calculate the total amount of culture medium required based on the requirement of 10 mL of PDA culture medium for each culture dish. Weigh a certain amount of peeled potatoes, cut them into small pieces and put them into a pot. Add 1000 mL of water and heat the pot until the potatoes are soft but not mushy. Filter them while hot with 6-8 layers of gauze and discard the residue. Add water to the filtrate to 1000 mL.

[0256] (2) Heat to dissolve: Place the filtrate in a pot and add glucose (20 g / 1000 mL distilled water) and agar powder (18 g / 1000 mL distilled water). Heat over low heat and stir constantly with a glass rod to prevent the agar powder from sticking to the bottom or overflowing. After the agar is completely dissolved, add water to the required amount.

[0257] (3) Packaging and autoclaving: Pack the prepared culture medium into 500 ml conical flasks. It is best to pack no more than half of the conical flask’s volume, seal it with sealing film, and sterilize it in an autoclave for later use.

[0258] 3. Solution preparation of synthesized coumarin-pyridine derivatives

[0259] The compound solution was prepared at a concentration of 100 μg / mL, that is, 10 mg of the compound was accurately weighed and placed in a centrifuge tube, 1000 μL of dimethyl sulfoxide (DMSO) was added using a pipette, and ultrasonic vibration was applied to completely dissolve the compound solution, and the compound solution was prepared and sterilized under a UV sterilizer for 30 minutes.

[0260] 4. Experimental Procedure

[0261] Take 10mL of PDA culture medium and place it in a culture dish, then add 100μL of compound solution, shake gently, mark it, place it horizontally to cool (drug concentration is 100μg / mL), use 100μL of dimethyl sulfoxide (DMSO) as a blank control, and conduct 3 parallel experiments. Use commercially available drugs carbendazim and thiophanate-methyl as positive controls. Use a 0.7cm diameter puncher to take a lush bacterial cake and punch holes in concentric circles. Then inoculate it into the center of the new culture medium and invert it in a 25℃ constant temperature incubator. Use the cross method to measure the diameter of the colony at 96h, calculate the average diameter size, and calculate the compound inhibition rate.

[0262] The calculation formula of antibacterial rate is: I = [(D0-D t ) / (D0-0.7)]×100%

[0263] (I: mycelial growth inhibition rate, D0: blank colony diameter, D t : Colony diameter after drug treatment)

[0264] 5. Measurement results

[0265] The above-mentioned mycelium growth rate method was used to determine the inhibitory activity of synthetic pyridine coumarin derivative compounds against four common plant pathogens, namely, Botrytis cinerea, Alternaria solani, Fusarium oxysporum and Alternaria alternata. The experimental results are shown in Table 2.

[0266] Table 2

[0267]

[0268]

[0269] Note: In Table 2, higher values ​​represent higher antibacterial activity, and negative values ​​represent that the compounds have a growth-promoting effect on fungi.

[0270] Then, based on the above results, we selected 1a, 1b, 1c, 1d, 1i, 2d, 3b, 3c, and 3j with better antibacterial activity for EC 50 Test. The test method is the colony diameter method, PDA culture medium. The test concentrations of the compounds are: 100μg / mL, 50μg / mL, 25μg / mL, 12.5μg / mL, 6.25μg / mL. The test concentrations of the commercial drugs Cnidium monnieri and Azoxystrobin for comparison test compounds are: 100μg / mL, 50μg / mL, 25μg / mL, 12.5μg / mL, 6.25μg / mL. The test data are shown in Table 3:

[0271] Table 3

[0272]

[0273] The smaller the EC50 value, the lower the concentration of the drug, which can achieve 50% of the maximum effect, which means that the drug is more potent.

[0274] From EC 50 According to the test results, among these compounds, the EC values ​​of compounds 1d, 1i, and 3b for Alternaria alternata are 50 The values ​​were 30.957 μg / mL, 28.523 μg / mL, and 37.537 μg / mL, respectively, which showed comparable inhibitory activity to the positive controls of Cnidium monnieri and azoxystrobin. For Alternaria alternata, compounds 1a, 1b, and 1c showed good antibacterial activity, and their EC 50 The values ​​were 16.119μg / mL, 15.722μg / mL, and 17.738μg / mL, respectively, which were significantly better than the inhibitory activity of the two positive controls of Cnidium monnieri and azoxystrobin. For Fusarium oxysporum, compound 1b showed relatively good inhibitory activity, and its EC 50 The value was 21.784 μg / mL, which was much greater than the efficacy of Cnidium monnieri and Azoxystrobin. In addition, the EC 50 Value of R2 All of them are greater than 0.9, indicating that there is a good correlation between concentration and antibacterial effect. Overall, this series of compounds has a wide bactericidal spectrum and generally good activity. The compounds are particularly outstanding in inhibiting tomato early blight and crop wilt, and may become the leading compound molecules for the development and creation of green pesticides.

[0275] The same test method was used to test the half-inhibitory concentration (EC 50 ) The results are as follows.

[0276] Table 4

[0277]

[0278] It can be seen from Table 4 that the structures of the compounds of Comparative Example 1 in Table 4 and Compound 1b of the present invention are similar, and the main difference is the substituent on C-7. The substituent used in Comparative Example 1 in Table 4 is a straight-chain acid, and the substituent of Compound 1b of the present invention is 2-trifluoromethylbenzoic acid. By comparing the results, it can be seen that the EC of Compound 1b of the present invention is 50 The EC value (15.722 μg / mL) was significantly better than that of Comparative Example 1. 50 This indicates that when the substituent contains trifluoromethyl (-CF3) or halogen (-F, Cl, Br), the antifungal activity of the compound will be significantly improved on the previous antifungal activity.

[0279] It can be seen from the above results that the pyridine coumarin derivatives of the present invention have a good application value in resisting plant-derived fungi. In particular, the fungi targeted are Botrytis cinerea, which causes gray mold of strawberries and tomatoes, Altemaria solani, which causes early blight of tomatoes, Fusarium oxysporum, which causes crop wilt, and Alternaria alternata, which causes black mold of tomatoes. The fungicidal effect has good inhibitory activity against four common basic fungi of plants, and can be used as a lead compound for creating new agricultural fungicides for the treatment or prevention of plant fungal infectious diseases. Therefore, the pyridine coumarin derivatives of the present invention can be used in the preparation of antifungal drugs, especially in the preparation of antifungal drugs. The effect is obvious.

[0280] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0281] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0282] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0283] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

Claims

1. A pyridine coumarin derivative, characterized in that , the pyridine coumarin derivative is selected from the compounds represented by the following structural formula: Wherein, R1, R2, and R3 are the same or different and are independently selected from Among them, R a is selected from alkenyl, substituted or unsubstituted aryl; and only one of the substituents appears at the same time in OR1, OR2, and OR3;.

2. The pyridine coumarin derivative according to claim 1, characterized in that: The pyridine coumarin derivatives are selected from the compounds represented by the following general structural formula: Wherein, R1 in Formula 1 is selected from R 1a is selected from alkenyl, substituted or unsubstituted thienyl, substituted or unsubstituted phenyl; Preferably, R 1a A phenyl group substituted with at least one substituent selected from C2-C8 alkenyl; halogen-substituted thienyl, thienyl; halogen, C1-C4 alkyl, fluoroalkyl; More preferably, R 1a is selected from a C3-C8 alkenyl, a phenyl substituted by a halogen and a C1-C2 alkyl, a phenyl substituted by a fluoroalkyl, a phenyl substituted by a fluoroalkyl and a halogen, a thienyl substituted by a halogen, and a thienyl; More preferably, the formula 1 is selected from the following compounds:

3. The pyridine coumarin derivative according to claim 1, characterized in that: The pyridine coumarin derivatives are selected from the following structural formulas: R2 in Formula 2 is selected from Among them, R 2a is selected from substituted or unsubstituted thienyl; Preferably, R 2a is selected from halogen-substituted thienyl, thienyl; More preferably, R 2a is selected from a halogen-substituted thienyl, thienyl; More preferably, the formula 2 is selected from the following compounds:

4. The pyridine coumarin derivative according to claim 1, characterized in that: The pyridine coumarin derivatives are selected from the following structural formulas: R3 in Formula 3 is selected from Among them, R 3a is selected from alkenyl, substituted or unsubstituted thienyl, substituted or unsubstituted phenyl; Preferably, R 3a A phenyl group substituted with at least one substituent selected from C2-C8 alkenyl; halogen-substituted thienyl, thienyl; halogen, C1-C4 alkyl, fluoroalkyl; More preferably, R 3a A phenyl group selected from the group consisting of a C3-C8 alkenyl group, a phenyl group substituted by a halogen and a C1-C2 alkyl group, a phenyl group substituted by a fluoroalkyl group, a phenyl group substituted by a fluoroalkyl group and a halogen, a thienyl group substituted by a halogen, and a thienyl group; More preferably, the formula 3 is selected from the following compounds:

5. A method for preparing a pyridine coumarin derivative, characterized in that: The following steps are involved: reacting substrate 1 with substrate 2, a condensing agent, and a basic catalyst in a solvent to obtain the pyridine-type pyridine-type coumarin derivative; Wherein, substrate 1 is selected from the following structural formula: Among them, only one of the three hydroxyl groups in formula B exists at the same time; Substrate 2 is selected from At least one of R a R according to any one of claims 1 to 4 a The corresponding same; The pyridine coumarin derivative according to any one of claims 1 to 4 is preferably prepared by the method.

6. The method for preparing the pyridine coumarin derivatives according to claim 5, characterized in that: The substrate 1 is selected from one of the following compounds: Substrate 2 is selected from At least one of R 1a , R 2a , R 3a R according to any one of claims 1 to 4 1a , R 2a , R 3a The corresponding same.

7. The method for preparing the pyridine coumarin derivatives according to claim 5, characterized in that: The condensing agent is selected from at least one of EDC and DCC; and / or, The alkaline catalyst is selected from at least one of 4-dimethylaminopyridine and 1-hydroxybenzotriazole; and / or, The solvent is selected from at least one of dichloromethane or a mixture of petroleum ether and ethyl acetate.

8. The method for preparing the pyridine coumarin derivatives according to claim 5, characterized in that: The molar ratio of substrate 2 to substrate 1 is (2-4):1; and / or, The molar ratio of the condensing agent to the substrate 1 is (3-6):1; and / or, The molar ratio of the condensing agent to the alkaline catalyst is (5-8):1; and / or, The mass volume ratio of the condensing agent to the solvent is (2-20) mg: 1 mL; and / or, The reaction time is 6-10h.

9. Use of the pyridine coumarin derivative according to any one of claims 1 to 4 in at least one of antifungal, antiviral, anti-inflammatory or antitumor activities.

10. The use according to claim 9, wherein the pyridine coumarin derivative is used for inhibiting at least one of Botrytis cinerea, Alternaria solani, Fusarium oxysporum or Alternaria alternata.

Images