阅读说明：本技术 香豆素-噻唑酯类衍生物及其制备方法和应用 (Coumarin-thiazole ester derivatives, and preparation method and application thereof ) 是由 吕献海 刘浩 夏东国 程祥 巩杰秀 于 2019-09-30 设计创作，主要内容包括：本发明公开了一种香豆素-噻唑酯类衍生物及其制备方法与应用,属于生物化学技术领域,所述香豆素-噻唑酯类衍生物是以中间体4与中间体7为原料,加入催化量的DCC、DMAP,在0℃下反应10-15小时即可通过一步反应合成目标产物,该合成方法后处理过程简单,通过化学合成的方式合成了24种目标化合物,使得所制备的香豆素-噻唑酯类衍生物具有广谱的抗细菌活性。本申请为开发以香豆素-噻唑酯类衍生物为活性成分的新型抗细菌剂提供了基础。(The invention discloses a coumarin-thiazole ester derivative and a preparation method and application thereof, belonging to the technical field of biochemistry, wherein the coumarin-thiazole ester derivative takes an intermediate 4 and an intermediate 7 as raw materials, a catalytic amount of DCC and DMAP is added, and a target product can be synthesized through one-step reaction after reacting for 10-15 hours at 0 ℃. The application provides a foundation for developing a novel antibacterial agent taking coumarin-thiazole ester derivatives as active ingredients.)

1. The coumarin-thiazole ester derivative is characterized in that the structural formula is shown as the formula I:

wherein R is¹Is hydrogen or halogen; r²Is diethylamino; r³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl; when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The site is hydrogen.

2. A method for preparing coumarin-thiazole ester derivatives according to claim 1, which comprises the following steps:

dissolving the intermediate 4 and the intermediate 7, adding DCC and DMAP, reacting at 0 ℃ for 10-15 hours, and purifying to obtain coumarin-thiazole ester derivatives;

wherein R is¹Is hydrogen or halogen; r²Is diethylamino; r³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl; wherein when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The site is hydrogen.

3. The method for preparing coumarin-thiazole ester derivatives according to claim 2, wherein the intermediate 4 is prepared as follows:

after dissolving salicylaldehyde 1 and Meldrum's acid 2, adding pyridine and acetic acid, refluxing, waiting for crystallization of a crude product, and obtaining an intermediate 4 after suction filtration and alcohol washing, wherein the preparation process of the intermediate 4 is as follows:

wherein R is¹Is hydrogen or halogen; r²Is diethylamino; when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The position is hydrogen; a is piperidine, acetic acid and ethanol, and b is reflux for 2 h.

4. The method for preparing coumarin-thiazole ester derivatives according to claim 2, wherein the intermediate 7 is prepared as follows:

adding a compound 5 and ultra-dry tetrahydrofuran into a container filled with nitrogen, cooling to 78 ℃ below zero, then adding n-butyllithium, reacting for a period of time, adding a compound 6 into the container, continuing to react for a period of time, heating a reaction system to room temperature, continuing to react for a period of time, quenching the reaction with water after the reaction is finished, and purifying to obtain an intermediate 7, wherein the preparation process of the intermediate 7 is as follows:

wherein R is³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl.

5. The method of claim 2, wherein the molar ratio of intermediate 4 to intermediate 7 is 1.1: 1.

6. The method for preparing coumarin-thiazole ester derivatives according to claim 2, wherein the molar ratio of the DCC to DMAP is 1.5: 0.1.

7. The method for preparing coumarin-thiazole ester derivatives according to claim 3, wherein the molar ratio of salicylaldehyde 1 to mucic acid 2 is 1: 1.

8. The method for preparing coumarin-thiazole ester derivatives according to claim 3, wherein the molar ratio of pyridine to acetic acid is 4: 1.

9. The preparation method of the coumarin-thiazole ester derivative according to claim 4, wherein the molar ratio of the compound 5 to the compound 6 is 1:3, the reaction is carried out for 0.75h after n-butyllithium is added, the reaction is carried out for 1h after the compound 6 is added, and the reaction is carried out for 2h after the temperature is raised to room temperature.

10. Use of the coumarin-thiazole ester derivatives according to claim 1 as antibacterial agents.

Technical Field

The invention relates to the technical field of biochemistry, and particularly relates to a coumarin-thiazole ester derivative and a preparation method and application thereof.

Background

The spread of drug-resistant bacteria poses a significant threat to human health and increases morbidity and mortality. Microbial infections such as bacteria and fungi cause about one fifth of the total deaths in the world. With respect to antibiotic resistant bacteria, over the last two decades, the U.S. food and drug administration and the european drug administration have disclosed that only two new classes of antibiotics (lipopeptides and oxazolidinones) have been developed and approved.

As a basic ribozyme of cells, DNA topoisomerase (DNA Topo) is involved in life processes such as cell replication, transcription and mitosis. Bacterial topoisomerase II (DNA helicase) and topoisomerase iv (topo iv) are effective targets for the development of novel antibacterial agents. Topo II inhibitors have two main structural classes, namely quinolones and coumarins. However, mutation of the quinolone binding site of Topo II results in resistance to the quinolone. To address this problem, an effective approach is to retain the existing antibiotic core scaffold and continually change the new compounds without reducing their antibacterial activity.

The neomycin is one of representative drugs of coumarin antibiotics, and has a good inhibition effect on DNA topoisomerase. Coumarin is widely present in secondary plant metabolites. There have been and are described to date a number of 1800 different natural coumarins, many of which have high levels of biological activity, such as insecticidal, antioxidant, anticancer, anti-HIV, antifungal, antibacterial and antibiotic activity. Therefore, modification of the coumarin backbone to discover novel topoisomerase II inhibitors is feasible and of great significance to address existing bacterial resistance issues.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide a coumarin-thiazole ester derivative, and the invention provides 24 coumarin-thiazole ester derivatives, provides chemical structures thereof and verifies antibacterial activity thereof.

The invention also aims to provide a preparation method of the coumarin-thiazole ester derivatives, a series of coumarin-thiazole ester derivatives are prepared by taking thiazole and coumarin as raw materials and substituting different substituents, and the method and the used equipment are simple and easy to implement.

The invention also provides an application of the coumarin-thiazole ester derivatives, and the identification result shows that the coumarin-thiazole ester derivatives have obvious inhibition effects on staphylococcus aureus, listeria, escherichia coli and salmonella by applying a series of prepared coumarin-thiazole ester derivatives to different bacterial diseases.

To achieve these objects and other advantages in accordance with the present invention, there is provided a coumarin-thiazole ester derivative, represented by the following formula i:

wherein R is¹Is hydrogen or halogen; r²Is diethylamino; r³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl; when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The site is hydrogen.

The invention also provides a preparation method of the coumarin-thiazole ester derivative, which comprises the following steps:

and dissolving the intermediate 4 and the intermediate 7, adding DCC and DMAP, reacting at 0 ℃ for 10-15 hours, and purifying to obtain the coumarin-thiazole ester derivative.

Wherein R is¹Is hydrogen or halogen; r²Is diethylamino; r³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl; wherein when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The site is hydrogen.

Preferably, the preparation method of the intermediate 4 comprises the following steps:

dissolving salicylaldehyde 1 and Meldrum's acid 2, adding pyridine and acetic acid, refluxing, waiting for crude product crystallization, performing suction filtration, and washing with alcohol to obtain an intermediate 4, wherein the preparation process of the intermediate 4 is as follows, and in the process of preparing the intermediate 4 from the salicylaldehyde 1 and the Meldrum's acid 2, the intermediate 3 is a transition product:

wherein R is¹Is hydrogen or halogen; r²Is diethylamino; when R is¹When the position has a substituent, R²The position is hydrogen; when R is²When the position has a substituent, R¹The position is hydrogen, a is piperidine, acetic acid and ethanol, and b is reflux for 2 h.

Preferably, the preparation method of the intermediate 7 comprises the following steps:

adding the compound 5 and ultra-dry tetrahydrofuran into a container filled with nitrogen, cooling to 78 ℃ below zero, then adding n-butyllithium, reacting for a period of time, adding the compound 6 into the container, continuing to react for a period of time, heating the reaction to room temperature, continuing to react for a period of time, quenching the reaction with water after the reaction is finished, and purifying to obtain an intermediate 7, wherein the preparation process of the intermediate 7 is as follows:

wherein R is³Is phenyl, p-chlorophenyl, m-chlorophenyl, o-chlorophenyl, p-tolyl, isobutyl or naphthyl.

Preferably, the molar ratio of intermediate 4 to intermediate 7 is 1.1: 1.

Preferably, DCC and DMAP are added in a molar ratio of 1.5: 0.1.

Preferably, the molar ratio of salicylaldehyde 1 to mucic acid 2 is 1: 1.

Preferably, pyridine is added in a molar ratio of 4:1 to acetic acid.

Preferably, the molar ratio of compound 5 to compound 6 is 1: 3.

Preferably, n-butyllithium is added and the reaction is carried out for 0.75h, the compound 6 is added and the reaction is carried out for 1h, and the reaction is carried out for 2h after the temperature is raised to room temperature.

The invention also provides application of the coumarin-thiazole ester derivative in serving as an antibacterial agent.

The invention has at least the following beneficial effects:

the coumarin-thiazole ester derivative disclosed by the invention takes the intermediate 4 and the intermediate 7 as raw materials, a catalytic amount of DCC and DMAP is added, and the target product can be synthesized through one-step reaction after the reaction is carried out for 10-15 hours at the temperature of 0 ℃. The method of the invention prepares 24 different derivatives, provides the chemical structures of the derivatives and verifies the antibacterial activity of the derivatives, and the result shows that most compounds have general inhibition effect; compound 8p showed excellent antibacterial activity against 4 bacteria, IC₅₀The values were 21.386,17.142,28.401 and 15.971. mu.M, respectively. Of these compounds, 8i and 8v exhibited the best antibacterial activity against staphylococcus aureus, and 8x exhibited the best antibacterial activity against listeria. The application provides a foundation for developing a novel antibacterial agent taking coumarin-thiazole ester derivatives as active ingredients.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a synthetic route diagram of the present invention.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The specification and examples are exemplary only.