An aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and its preparation method and application

Abstract

The present invention provides an aminohydantoin Schiff base 4-pyridine quaternary ammonium salt precursor compound and its preparation method and application, which belongs to the synthesis and application technical field of quaternary ammonium salt Schiff base halamine high-efficiency composite antibacterial agent. Aminohydantoin hydrochloride, 4-pyridine formaldehyde and propylene bromide are used as raw materials to prepare an aminohydantoin Schiff base 4-pyridine quaternary ammonium salt precursor compound. And, the application process of the precursor compound is to pretreat the fiber or fabric with 3-mercaptopropyltriethoxysilane, then arrange it with the precursor compound, and finally halogenate it to obtain an antibacterial material. The method of the present invention has mild reaction conditions, simple process and good antibacterial effect. The 1-ADPAH-R antibacterial agent synthesized by the method and its halamine precursor combine the advantages of multiple antibacterial structures, so that the antibacterial agent has water solubility, is easy to operate when preparing the antibacterial material, and can prepare an antibacterial material with excellent antibacterial properties.

Description

Technical Field

[0001] The invention specifically relates to an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and a preparation method and application thereof, and belongs to the technical field of synthesis and application of quaternary ammonium salt Schiff base halogenamine high-efficiency composite antibacterial agents. Background Art

[0002] Cotton fabrics have good moisture absorption and air permeability and have many gaps inside, which provide a suitable environment for the growth and reproduction of microorganisms, leading to the generation of odor, skin allergies, cross-infection in hospitals, etc., affecting the health of users. With the continuous improvement of public health awareness and the frequent occurrence of infectious diseases, the demand for antibacterial textiles is increasing significantly. In addition, due to the uncontrolled abuse of antibiotics, corresponding drug-resistant bacteria have appeared in a short time after the development of antibacterial agents, which brings huge challenges to the medical and health field. Therefore, we urgently need to develop new and efficient antibacterial agents, as well as more efficient and quicker finishing methods.

[0003] Pyridine quaternary ammonium salt is a new type of quaternary ammonium salt. Since the drug resistance of some drug-resistant strains is caused by the reduction of cell membrane permeability, it has great potential in controlling bacterial infection and inhibiting drug resistance. The positive charge on pyridine quaternary ammonium salt is more concentrated, and it has stronger bactericidal ability. In addition, it has stronger hydrophilicity. N-halamine has the advantages of high bactericidal efficiency, regeneration and lower corrosivity than free halogens. Schiff base not only has antibacterial properties, but also has excellent stability. However, the use of only a single antibacterial agent has shortcomings, such as: the antibacterial property of quaternary ammonium salt is related to the permeability of bacterial cell membrane, so it cannot effectively kill Gram-negative bacteria with thick cell walls; N-halamine is relatively hydrophobic and cannot fully contact with bacterial suspension. In addition, N-halamine will be consumed during use, the antibacterial effect is not long-lasting, and it is easy to dissolve.

[0004] Although the prior art CN201510252801.1 "Pyridine quaternary ammonium salt type halamine antibacterial agent and its preparation method" discloses that the synergistic effect of pyridine quaternary ammonium salt and halamine solves the problem of poor water solubility of the antibacterial agent, the pyridine quaternary ammonium salt lacks reactive active groups (such as hydroxyl groups, alkenyl groups, etc.) and is a non-permanent fixative or reactive antibacterial agent. It can only enter the fabric, fiber and / or yarn through methods such as adhesive coating, and it is difficult to fix on the adhesive, fiber, yarn and / or fabric; CN202011576326.0 "A method for biological antibacterial finishing of protein fibers" discloses that plasma amine oxidase is used to catalyze the oxidative deamination reaction of the primary amine groups in wool protein to form highly reactive aldehyde groups, and the generated aldehyde groups can react with the natural antibacterial agent chitosan amino group to form Schiff bases, A series of oxidative deamination reactions such as aldol condensation with the aldehyde group of another molecule or acetal reaction with the hydroxyl group can cross-link the two, which can improve the durability of chitosan on wool antibacterial finishing to a certain extent. However, there are fewer amino groups in the protein and the accessibility is low, so the reaction is uncontrollable, resulting in a small amount of chitosan grafted or cross-linked on the wool protein and it is difficult to control; and "Research on Antibacterial Functional Finishing of Cotton Fabrics Based on Schiff Base-Halamine Compounds, Wen Wen, Southwest University" disclosed: Among the current antibacterial finishing agents, halamine antibacterial agents have been widely studied due to their unique structure and ability to kill bacteria efficiently and quickly, but they are severely affected by ultraviolet rays and their antibacterial properties are not long-lasting; Schiff base compounds have a unique chemical structure and are a new type of antibacterial agent with broad-spectrum biological activity, and their antibacterial effect is not affected by ultraviolet rays. Summary of the invention

[0005] The inventors found in long-term research that pyridinium quaternary ammonium salt, N-halamine and Schiff base have complementary properties, and there is a strengthening synergistic effect between the three. Among them, pyridinium quaternary ammonium salt effectively compensates for the hydrophobicity of N-halamine; quaternary ammonium salt can attract anionic bacteria to the N-halamine site through electrostatic attraction and be quickly killed, thereby effectively improving its antibacterial activity; the presence of Schiff base structure can effectively improve the stability and durability of antibacterial agents. Based on this, antibacterial functional groups with different advantages are combined, and a highly efficient composite antibacterial agent with a reactive group (such as olefin) is synthesized through a simple synthesis method to compensate for the deficiency of a single antibacterial agent. But at the same time, in this synthesis method, the inventors also found that after the reaction, there are many side reactions and low yield, which does not meet the high yield target required by the process. For this reason, the control conditions in the antibacterial agent synthesis method are specially limited to achieve an increase in the yield of the antibacterial agent to meet actual needs.

[0006] In order to achieve the above technical objectives, the following technical solutions are proposed:

[0007] The first purpose of the present invention is to provide an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, which is prepared using aminohydantoin hydrochloride, 4-pyridinecarboxaldehyde and propylene bromide as raw materials;

[0008] The aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is 1-(4-methyliminopyridine-1-allyl bromide)hydantoin, also known as 1-(4-aldimine pridine-1-allyl bromine)hydantoin, referred to as 1-ADPAH, and has the following chemical structure:

[0009]

[0010] In addition, the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is halogenated to obtain an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent, referred to as 1-ADPAH-R. The chemical structure of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent is as follows:

[0011]

[0012] Wherein, R represents a halogen group, R = Cl or Br.

[0013] The second object of the present invention is to provide a method for preparing an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, comprising the following steps:

[0014] 1) putting aminohydantoin hydrochloride into a container filled with water, adding sodium hydroxide powder to adjust the pH value of the solution to neutral, and then, drying the water therein to obtain a mixture A comprising aminohydantoin and sodium chloride; wherein aminohydantoin hydrochloride reacts with sodium hydroxide in an aqueous solution to obtain 1-aminohydantoin;

[0015] 2) dissolving the mixture A in hot ethanol, removing insoluble sodium chloride by suction filtration, and obtaining a mixed solution B comprising 1-aminohydantoin and ethanol; wherein the mixture A is dissolved in hot ethanol to increase the solubility of 1-aminohydantoin in the mixture A in ethanol, thereby facilitating subsequent filtration to remove the sodium chloride produced in the reaction of step 1), thereby improving the yield; and, “hot ethanol” may be “ethanol at a temperature of 70-80° C.”;

[0016] 3) adding an acidic solution and 4-pyridinecarboxaldehyde to the mixed solution B, and refluxing the mixture with ethanol at 60-80° C. for 18 h to obtain a mixed solution C containing aminohydantoin pyridine Schiff base and ethanol;

[0017] The ethanol and unreacted 4-pyridinecarboxaldehyde in the mixed solution C are removed by vacuum filtration to obtain compound D (i.e., aminohydantoin pyridine Schiff base);

[0018] 4) Add compound D and allyl bromide to dimethyl sulfoxide, react at 60-85° C. for 24 hours to obtain a mixture E including 1-(4-methyliminopyridine-1-allyl bromide) hydantoin and allyl bromide, then wash the dimethyl sulfoxide and unreacted allyl bromide with ethanol or ethyl acetate, filter and dry, and use deionized water as solvent to recrystallize the precipitated product: 1-(4-methyliminopyridine-1-allyl bromide) hydantoin, to obtain an aminohydantoin Schiff base 4-pyridine quaternary ammonium salt precursor compound;

[0019] The reaction process involved is as follows:

[0020]

[0021] Preferably, in step 1), the molar ratio of aminohydantoin hydrochloride to sodium hydroxide is 1:1, and the pH value is adjusted to 6-7.

[0022] Preferably, in step 3), the molar ratio of the added 4-pyridinecarboxaldehyde to aminohydantoin hydrochloride is 1:1.1-1.2; and, since the Schiff base structure is easily decomposed in an overly acidic environment, the acidity of the acidic solution cannot be too strong, and for this reason, glacial acetic acid solution is preferred.

[0023] Preferably, in step 4), the molar ratio of aminohydantoin pyridine Schiff base to allyl bromide is 1:1.2. In addition, the amount of dimethyl sulfoxide used should not be too much, and it is sufficient to dissolve part of the aminohydantoin pyridine Schiff base. For this reason, the molar concentration of aminohydantoin pyridine Schiff base is limited to 0.5-2 mol / L.

[0024] The third purpose of the present invention is to apply the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound to the preparation of antibacterial materials, wherein 3-mercaptopropyltriethoxysilane (MPTES) is subjected to a hydrolysis reaction, and the siloxy group is hydrolyzed into a hydroxyl group, which condenses with the hydroxyl group on the material to be treated to form an ether bond structure, that is, MPTES is grafted onto the fiber surface; then, the prepared halamine precursor compound is grafted onto the fiber surface through a mercapto-ene free radical addition reaction, and finally, the final antibacterial product is obtained through a halogenation treatment. The steps include:

[0025] (1) Immerse the material to be treated in the pretreatment solution for 5 minutes, take it out, place it in an oven at 120-140°C for 5 minutes, repeat 3 times, and dry it to obtain a pretreated material;

[0026] (2) immersing the pretreated material in an antimicrobial treatment solution, placing it under an ultraviolet lamp (120W), irradiating it on one side at room temperature for 60 minutes, taking it out, washing the textile thoroughly with laundry detergent and deionized water, and drying it in a constant temperature oven at 50°C to obtain an antimicrobial finishing material;

[0027] (3) Immersing the antibacterial finishing material in the halogenation reaction solution, sealing, reacting for 20 minutes, taking it out, washing it thoroughly with detergent and deionized water, and drying it in a constant temperature oven at 50° C. to obtain the final antibacterial material.

[0028] Furthermore, the material to be treated includes various natural fibers or synthetic cellulose textiles.

[0029] Furthermore, in step (1), the bath ratio of the material to be treated and the pretreatment liquid is 1:30, wherein the preparation method of the pretreatment liquid comprises: mixing ethanol and pure water in a volume ratio of 4:1, adding 3-mercaptopropyltriethoxysilane in an amount of 5%; then, adjusting the pH to 3.5 with glacial acetic acid, and stirring with a magnetic stirrer for 30 minutes to prepare the pretreatment liquid.

[0030] Furthermore, in step (2), the bath ratio of the pretreatment material to the antibacterial treatment liquid is 1:20-100, preferably, the bath ratio is 1:50. The preparation method of the antibacterial treatment liquid comprises: dissolving the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and the water-soluble photoinitiator 2,2-dihydroxymethyl propionic acid in water to form an aqueous solution, wherein the content of the photoinitiator in the aqueous solution is 1wt%.

[0031] Furthermore, in step (3), the bath ratio of the antibacterial finishing material to the reaction liquid is 1:30, wherein the preparation method of the halogenated reaction liquid comprises: adding glacial acetic acid to a sodium hypochlorite solution or a sodium hypobromite solution with a mass fraction of 10wt%, and adjusting the pH to neutral to prepare the solution.

[0032] In the specific application of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, the textile material can be treated with the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and then subjected to a halogenation reaction to finally obtain the antibacterial material; or the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound can be first halogenated to prepare the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halamine antibacterial agent, and then the textile material is directly treated to obtain the antibacterial material, that is, the choice is made according to actual needs.

[0033] In the method of preparing antibacterial materials, a chemical grafting method based on the mercapto-ene click reaction is combined with existing mature technology (impregnation-curing treatment) to ensure that the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is stably and efficiently grafted to the fiber surface, ultimately forming an antibacterial product.

[0034] In the preparation method of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound of the present technical solution, a cyclic N-halamine with better stability is selected; and the presence of the olefin structure allows the final high-efficiency composite antibacterial agent to be grafted and cross-linked on the target product in a variety of ways to form a permanent fixation; in addition, the water-soluble antibacterial agent has better prospects in practical applications.

[0035] The dissolution-type antibacterial agents in the prior art are slowly released into the environment during use, which not only reduces their antibacterial effect, but also causes certain pollution to the environment. The high-efficiency composite antibacterial agent containing olefin groups of the present invention can be firmly bonded to cotton fabrics by chemical grafting, thereby achieving durable antibacterial; in addition, (3-mercaptopropyl) triethoxysilane (MPTES) is used as a grafting medium, and after a hydrolysis reaction, it can condense with the hydroxyl groups on the cotton fabric to form an ether bond structure, thereby grafting MPTES to the surface of the cotton fabric. Thiol-ene click chemistry is a type of click chemistry reaction. In the presence of ultraviolet light, molecules containing olefin groups can be covalently linked to thiol-containing MPTES through a thiol-ene click reaction. The thiol-ene click reaction is used for functional finishing of cotton fabrics, which is not only simple in method, but also has a long-lasting finishing effect.

[0036] The beneficial technical effects brought about by adopting this technical solution are:

[0037] 1. The present invention combines the advantages of pyridinium quaternary ammonium salt, N-halamine and Schiff base, overcomes the problems of low preparation yield, low water solubility in application and poor antibacterial performance in the complementary process of pyridinium quaternary ammonium salt, N-halamine and Schiff base, and makes the antibacterial agent of aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound halogenated to achieve high-efficiency antibacterial regeneration and long-lasting non-leaching effects. It solves the problems of the existing halamine antibacterial agents such as short-lasting antibacterial efficacy and easy dissolution;

[0038] Second, in the present invention, the hydrophilicity of the halamine precursor decreases after halogenation, which is not conducive to contact with microorganisms, thereby causing its antibacterial performance to decrease. For this reason, the introduction of pyridinium quaternary ammonium salt into the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound can improve the hydrophilicity of the antibacterial agent;

[0039] 3. In the present invention, the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is used to perform antibacterial finishing on fibers or fabrics, 3-mercaptopropyltriethoxysilane is subjected to a hydrolysis condensation reaction with the hydroxyl groups on the surface of the fibers or fabrics, 3-mercaptopropyltriethoxysilane can be grafted onto the surface of the fibers or fabrics, and then the prepared halamine precursor compound is bonded to the surface of the fibers or fabrics through a mercapto-ene click reaction, thereby improving the stability and washability of the finished fibers or fabrics;

[0040] Fourth, in the present invention, the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is used to prepare antibacterial materials. After antibacterial tests, the obtained antibacterial materials have excellent antibacterial properties (up to 100%) and high antibacterial efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a synthetic route diagram of 1-ADPAH in Example 5 of the present invention;

[0042] Figure 2 is the nuclear magnetic resonance image of 1-ADPAH in Example 5 of the present invention;

[0043] Figure 3 is a Fourier transform infrared spectrum of 1-ADPAH in Example 5 of the present invention;

[0044] Figure 4 This is a schematic diagram of the process of antibacterial finishing of cotton fabrics by 1-ADPAH in Application Example 1 of the present invention;

[0045] Figure 5 This is a scanning electron microscope image of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention;

[0046] Figure 6 This is the X-ray energy spectrum of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention;

[0047] Figure 7 This is a Fourier infrared spectrum of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention;

[0048] Figure 8 Schematic diagram of the antibacterial performance of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention (I);

[0049] Fig. 9 Schematic diagram of the antibacterial performance of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention (II);

[0050] Fig.10 Schematic diagram of the antibacterial performance of cotton fabric treated with 1-ADPAH-Cl in Application Example 1 of the present invention (III). DETAILED DESCRIPTION

[0051] The following is a clear and complete description of 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 of 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.

[0052] Example 1

[0053] This embodiment provides: a precursor compound of aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt is proposed, which is prepared using aminohydantoin hydrochloride, 4-pyridinecarboxaldehyde and allyl bromide as raw materials;

[0054] The aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is 1-(4-methyliminopyridine-1-allyl bromide)hydantoin, also known as 1-(4-aldimine pridine-1-allyl bromine)hydantoin, referred to as 1-ADPAH, and has the following chemical structure:

[0055]

[0056] In addition, the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is halogenated to obtain an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent, referred to as 1-ADPAH-R. The chemical structure of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent is as follows:

[0057]

[0058] Wherein, R represents a halogen group, R = Cl or Br.

[0059] Example 2

[0060] Based on Example 1, this example provides a method for preparing a corresponding aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, comprising the following steps:

[0061] 1) adding aminohydantoin hydrochloride into water, adjusting the pH value to 7, and drying the water in a rotary evaporator to obtain a mixture A;

[0062] 2) Dissolve the mixture A in hot ethanol and filter to obtain a mixture B;

[0063] 3) adding an acidic solution and 4-pyridinecarboxaldehyde to the mixed solution B, and refluxing with ethanol to obtain a mixed solution C; then, filtering to obtain a compound D, which is aminohydantoin pyridine Schiff base;

[0064] The amount of 4-pyridinecarboxaldehyde added is based on a molar ratio of 4-pyridinecarboxaldehyde to aminohydantoin hydrochloride of 1:1.1;

[0065] 4) adding aminohydantoin pyridine Schiff base and allyl bromide to dimethyl sulfoxide, controlling the molar concentration of aminohydantoin pyridine Schiff base to 1.5 mol / L, reacting to obtain a mixture E; then, washing with ethanol or ethyl acetate, filtering, and drying; using deionized water as a solvent, recrystallizing to precipitate the final product 1-(4-methyliminopyridine-1-allyl bromide)hydantoin, and obtaining aminohydantoin Schiff base 4-pyridine quaternary ammonium salt halamine antibacterial agent;

[0066] The amount of allyl bromide added is calculated based on a molar ratio of aminohydantoin pyridine Schiff base to allyl bromide of 1:1.2;

[0067] The reaction process in the preparation method is as follows:

[0068]

[0069] In addition, the preparation method of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent includes: halogenating the obtained aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound to obtain the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halogenamine antibacterial agent.

[0070] Example 3

[0071] On the basis of Example 2, this example further defines the conditions in the preparation method of the final product, aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, to further improve the stability and sustainability of the preparation method, while reducing costs and increasing the yield of the product. Among them:

[0072] In step 1), sodium hydroxide is used to adjust the pH value, and the molar ratio of aminohydantoin hydrochloride to sodium hydroxide is 1:1.

[0073] In step 3), the acidic solution is a weak acid solution, preferably a glacial acetic acid solution; and ethanol is refluxed at 70° C. for 18 hours.

[0074] In step 4), the reaction is carried out at 75° C. for 24 h.

[0075] Example 4

[0076] This embodiment takes the production of antibacterial materials as an example, and uses the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound to prepare the antibacterial material.

[0077] The preparation method of the antibacterial material comprises:

[0078] (1) Soaking the material to be treated (various natural fibers or synthetic cellulose textiles) in the pretreatment solution at a bath ratio of 1:30 between the material to be treated and the pretreatment solution, and drying to obtain the pretreated material;

[0079] The preparation method of the pretreatment liquid includes: mixing ethanol and pure water at a volume ratio of 4:1, adding 5% 3-mercaptopropyltriethoxysilane; then adjusting the pH to 3.5 with glacial acetic acid, stirring with a magnetic stirrer for 30 minutes

[0080] (2) immersing the pretreated material in the antibacterial treatment solution at a bath ratio of 1:50, irradiating with ultraviolet light, washing, and drying to obtain an antibacterial finishing material;

[0081] The preparation method of the antibacterial treatment liquid comprises: dissolving the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt halamine antibacterial agent and the water-soluble photoinitiator 2,2-dihydroxymethyl propionic acid in water to form an aqueous solution, wherein the content of the photoinitiator in the aqueous solution is 1wt%;

[0082] (3) With the bath ratio of the antibacterial finishing material to the reaction liquid being 1:30, the antibacterial finishing material is immersed in the halogenation reaction liquid, reacted, washed, and dried to obtain the antibacterial material.

[0083] The preparation method of the halogenation reaction liquid comprises: adding glacial acetic acid to a sodium hypochlorite solution (or sodium hypobromite solution) with a mass fraction of 10 wt %, and adjusting the pH to neutral.

[0084] Example 5

[0085] This embodiment provides: a method for preparing an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, specifically comprising:

[0086] (1) 1 mol of aminohydantoin hydrochloride is placed in a round-bottom flask containing 100 ml of water, sodium hydroxide is added to adjust the pH of the solution to neutral, and then the water is evaporated by rotary evaporation to obtain a mixture of 1-aminohydantoin and sodium chloride, which is a light yellow powder;

[0087] (2) dissolving the mixture obtained in step (1) in hot ethanol, filtering and removing insoluble sodium chloride to obtain a mixture of 1-aminohydantoin and ethanol;

[0088] (3) adding 1 mL of glacial acetic acid and 0.1 mol of 4-pyridinecarboxaldehyde to the mixed solution of 1-aminohydantoin and ethanol obtained in step (2), refluxing in ethanol at 80° C. for 18 hours, and filtering to obtain aminohydantoin pyridine Schiff base in the form of a white powder;

[0089] (4) adding 1.2 mol of allyl bromide and DMSO to the aminohydantoin pyridine Schiff base obtained in step (3), reacting at 85° C. for 24 hours to obtain a mixture containing aminohydantoin pyridine allyl bromide; then, washing away DMSO and unreacted allyl bromide with ethanol, filtering, and washing with a large amount of hot water to dissolve the product in hot water, evaporating the water, dissolving it with hot water again, and cooling and crystallizing to obtain the final product.

[0090] Among them, the synthetic route of 1-ADPAH is as follows Figure 1As shown, after desalting, aminohydantoin hydrochloride reacts with 4-pyridine carboxaldehyde under neutral conditions to form a Schiff base structure. The introduction of 1-ADPAH-R generated by pyridinium quaternary ammonium salt into the halamine antibacterial agent can improve the hydrophilicity of the antibacterial agent. From the perspective of operation and practicality, the synthesized 1-ADPAH antibacterial agent with pyridinium quaternary ammonium salt structure has stronger hydrophilicity and is more convenient for antibacterial finishing with textiles.

[0091] In addition, the obtained 1-ADPAH was subjected to nuclear magnetic resonance analysis (nuclear magnetic resonance instrument, WNMR-I-400MHz, Wuhan Zhongke Oxford Spectroscopy Technology Co., Ltd.) and infrared spectroscopy analysis (Fourier transform infrared spectrometer, Nicolet iS10, ThermoFisher), and the results are as follows: Figure 2-3 As shown, it can be seen from the signal in the nuclear magnetic resonance image that the structure of the target synthetic compound corresponds one-to-one with the peak in the 1HNMR spectrum, so it can be determined that the synthetic product is the target synthetic compound 1-ADPAH; and the peak signal in the Fourier infrared spectrum can prove that the product is the target compound.

[0092] Application Example 1

[0093] This application example proposes to use the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound obtained in Example 5 for antibacterial finishing of cotton fabrics, specifically including:

[0094] (1) 3-mercaptopropyltriethoxysilane pretreatment of desized cotton fabric: The desized cotton fabric was pretreated with 3-mercaptopropyltriethoxysilane, the bath ratio of the pretreatment solution was 1:30, the ratio of ethanol to pure water was 4:1, the amount of MPTES added was 5%, the pH of the treatment solution was adjusted to 3.5 with glacial acetic acid and stirred with a magnetic stirrer for 30 minutes. Then, the desized cotton fabric was immersed in the pretreatment solution for 5 minutes, taken out and placed in an oven at 120 degrees for 5 minutes, and the drying was repeated 3 times to obtain the pretreated cotton fabric;

[0095] (2) Antimicrobial treatment of cotton fabric: prepare an antimicrobial treatment solution containing a certain proportion of aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and a water-soluble photoinitiator 2,2-dimethylol propionic acid at a bath ratio of 1:50. Immerse the pretreated cotton fabric in the antimicrobial treatment solution and irradiate it on one side under an ultraviolet lamp (120W) at room temperature for 60 minutes. Take out the fabric and wash it thoroughly with washing powder and deionized water, and dry it in a constant temperature oven at 50°C to obtain an antimicrobial treated cotton fabric.

[0096] (3) Halogenation treatment of antibacterial finished cotton fabric: a reaction solution with a bath ratio of 1:30 was prepared, the amount of sodium hypochlorite solution added was 10 wt%, the reaction solution was adjusted to neutral with glacial acetic acid, the antibacterial treated fabric was immersed in the reaction solution, sealed with plastic wrap, reacted for 20 min, the fabric was taken out, washed thoroughly with washing powder and deionized water, and dried in a constant temperature oven at 50°C to obtain the final antibacterial cotton fabric.

[0097] Among them, the process of antibacterial finishing of cotton fabrics with 1-ADPAH is as follows: Figure 4 The structure of the cotton fabrics before and after treatment was characterized by electron scanning (scanning electron microscope, Phenom Pro, Phenom World), X-ray spectroscopy (Thermo Scientific K-Alpha) and Fourier transform infrared spectroscopy (Nicolet iS10, ThermoFisher). Figure 5-7 As shown, the characterization results show that 1-ADPAH was successfully grafted onto cotton fabric.

[0098] In addition, the antibacterial properties of the obtained antibacterial cotton fabric were tested, and the results were as follows Figure 8-10 As shown. In the blank control, bacteria grew normally, indicating that the experiment was effective. After the cotton fabrics were treated with different concentrations of 1-ADPAH-Cl, the number of colonies in the culture dish decreased as the concentration of 1-ADPAH-Cl increased. When the concentration of 1-ADPAH-Cl reached 1%, the inhibition rate of Escherichia coli and Staphylococcus aureus could reach 100%. The results showed that it had an inhibitory effect on the growth of bacteria.

[0099] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent substitution and inclusion made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. An aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, characterized in that: It is prepared using aminohydantoin hydrochloride, 4-pyridinecarboxaldehyde and allyl bromide as raw materials; The chemical structural formula of the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound is as follows: 。 2. A method for preparing an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound, characterized in that: The steps include: 1) Add aminohydantoin hydrochloride Add into water, adjust pH value to 6-7, spin dry to obtain mixture A; 2) Dissolve mixture A in hot ethanol and filter to obtain mixture B; 3) Add acidic solution and 4-pyridinecarboxaldehyde to mixed solution B , reflux with ethanol to obtain a mixed solution C; then, filter and obtain compound D, which is aminohydantoin pyridine Schiff base ; The amount of 4-pyridinecarboxaldehyde added is calculated based on a molar ratio of 4-pyridinecarboxaldehyde to aminohydantoin hydrochloride of 1:1.1-1.2; 4) Add aminohydantoin pyridine Schiff base and allyl bromide to dimethyl sulfoxide , controlling the molar concentration of aminohydantoin pyridine Schiff base to 0.5-2 mol / L, reacting to obtain a mixture E; then, washing with ethanol or ethyl acetate, filtering, and drying; using deionized water as a solvent, recrystallizing to precipitate the product 1-(4-methyliminopyridine-1-allyl bromide)hydantoin, thereby obtaining an aminohydantoin Schiff base 4-pyridine quaternary ammonium salt precursor compound. ; The amount of allyl bromide added is based on a molar ratio of aminohydantoin pyridine Schiff base to allyl bromide of 1:1.

2.

3. The method for preparing the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound according to claim 2, characterized in that: In step 1), sodium hydroxide is used to adjust the pH value, and the molar ratio of aminohydantoin hydrochloride to sodium hydroxide is 1:

1.

4. The method for preparing the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound according to claim 2, characterized in that: In step 3), the acidic solution is a weak acid solution.

5. The method for preparing the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound according to claim 4, characterized in that: In step 3), ethanol is refluxed at 60-80° C. for 18 h.

6. The method for preparing the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound according to claim 2, characterized in that: In step 4), the reaction is carried out at 60-85° C. for 24 h.

7. The aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound as claimed in claim 1 or the aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound synthesized by the preparation method as claimed in any one of claims 2 to 6 is used for preparing antibacterial materials.

8. The use according to claim 7, characterized in that: The preparation method of the antibacterial material comprises: (1) Soaking the material to be treated in the pretreatment liquid and drying it to obtain the pretreated material; (2) immersing the pretreated material in the antibacterial treatment solution at a bath ratio of 1:20-100, irradiating with ultraviolet light, washing, and drying to obtain an antibacterial finishing material; The preparation method of the antibacterial treatment liquid includes: dissolving an aminohydantoin Schiff base 4-pyridinium quaternary ammonium salt precursor compound and a water-soluble photoinitiator 2,2-dihydroxymethyl propionic acid in water to form an aqueous solution, wherein the content of the photoinitiator in the aqueous solution is 1wt%; (3) Immersing the antibacterial finishing material in a halogenation reaction solution, reacting, washing, and drying to obtain an antibacterial material.

9. The use according to claim 8, characterized in that: The preparation method of the pretreatment liquid comprises: mixing ethanol and pure water at a volume ratio of 4:1, adding 3-mercaptopropyltriethoxysilane in an amount of 5%; then, adjusting the pH to 3.5 with glacial acetic acid, and stirring with a magnetic stirrer for 30 minutes.

10. The use according to claim 8, characterized in that: The preparation method of the halogenation reaction liquid comprises: adding glacial acetic acid to a sodium hypochlorite solution or a sodium hypobromite solution with a mass fraction of 10 wt %, and adjusting the pH to be neutral.

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