CN109305938B

CN109305938B - Norfloxacin metal complex and preparation method and application thereof

Info

Publication number: CN109305938B
Application number: CN201710621874.2A
Authority: CN
Inventors: 高广刚; 刘红; 杨帆; 韩晓宁; 周淑晶; 汪思奇; 李香兰
Original assignee: University of Jinan
Current assignee: University of Jinan
Priority date: 2017-07-27
Filing date: 2017-07-27
Publication date: 2022-03-15
Anticipated expiration: 2037-07-27
Also published as: CN109305938A

Abstract

The invention provides a norfloxacin metal complex, which is prepared by compounding norfloxacin, a compound containing an accessory group metal element and a polyacid compound, and the preparation method comprises the following steps: mixing norfloxacin, a compound containing an accessory group metal element and a polyacid compound, adjusting the pH value, heating for reaction, and performing post-treatment to obtain the norfloxacin metal complex. The complex is applied to surface bacteriostasis of various daily utensils, surface antibiosis of medical instruments, bacteriostasis by adopting various medicament formulations and the like. In the preparation method provided by the invention, the reaction process is easy to control and operate, the raw materials are easy to obtain, the yield is high, and the purification is easy.

Description

Norfloxacin metal complex and preparation method and application thereof

Technical Field

The invention relates to the field of medicines, and particularly relates to a norfloxacin metal complex, and a preparation method and application thereof.

Background

Quinolone drugs are a class of artificially synthesized antibacterial drugs. Has the obvious advantages of high efficiency, broad spectrum and the like, and nearly one hundred thousand quinolone drugs and derivatives thereof have been synthesized so far. The third-generation quinolone drug is represented by Norfloxacin (Norfloxacin), which is a derivative with a modified 4-quinolone structure, and fluorine (F) is added to the 6 th position, so the third-generation quinolone drug is also called fluoroquinolones (fluoroquinolones), and the structure increases fat solubility and enhances the penetrating power to tissue cells, so the third-generation quinolone drug has good absorption, high tissue concentration and long half-life period, and the antibacterial spectrum and the bactericidal effect are greatly increased.

The use of norfloxacin is more and more extensive, the congenital drug resistance frequency of bacteria to norfloxacin is extremely low, but with the wide use, the drug resistance of bacteria is continuously improved. The norfloxacin has the advantages of quick antibacterial effect, wide antibacterial spectrum, more comprehensive product development, low price and suitability for mass consumption. Therefore, it is a problem to be solved to improve the biological activity and reduce the drug resistance of bacteria.

Partial research shows that after the medicine molecule with bioactivity forms a complex with metal ions, the bioactivity of the medicine can be obviously improved, and the drug resistance of bacteria to the medicine is further reduced. But only a few simple complexes are researched, so that the novel norfloxacin metal complex with a rich substance structure is prepared, the biological activity of the medicament is effectively improved, other treatment effects can be brought, and the norfloxacin metal complex is effectively applied to in vivo and in vitro antibiosis, and has important significance.

Disclosure of Invention

In order to solve the above problems, the present inventors have conducted intensive studies and, as a result, have found that: mixing norfloxacin, a compound containing an accessory group metal element and a polyacid compound, adjusting the pH value, heating for reaction, and performing post-treatment to obtain the norfloxacin metal complex. The complex has excellent biological activity, and the present invention has been completed.

The object of the present invention is to provide the following:

in a first aspect, the present invention provides a norfloxacin metal complex, which is prepared by combining norfloxacin, a compound containing a metal element of the subgroup and a polyacid compound, and the complex structure can be represented as follows: (Z)_z{X[MO(NF)_n]_mWherein Z represents a cation, X represents a polyacid anion, and M represents a subgroup metal element.

Preferably, the first and second electrodes are formed of a metal,

z is a metal cation or an ammonium ion,

x is polyacid anion containing transition metal element, preferably gamma polyacid anion, more preferably polyacid anion containing VIB group metal element, especially preferably one of polyacid anion containing chromium element, molybdenum element or tungsten element,

m is a VB group metal element, preferably one of vanadium element, niobium element and tantalum element,

z is 1 to 4, preferably 1 to 3, for example 2;

n is 1 to 4, preferably 1 to 3, for example 2;

m is 1 to 4, preferably 1 to 3, for example 2.

In a second aspect, the present invention provides a process for the preparation of a norfloxacin metal complex, the process comprising the steps of:

(1) mixing Norfloxacin (NF), a compound containing an accessory group metal element and a polyacid compound, and optionally stirring;

(2) adjusting the pH of the mixture or a solution thereof to acidity;

(3) heating to react;

(4) after the reaction is finished, post-treatment is carried out to obtain a target product.

In a third aspect, the norfloxacin metal complex according to the first aspect is used, especially for antibiosis, preferably daily ware surface bacteriostasis, medical device surface bacteriostasis and bacteriostasis by adopting a pharmaceutical dosage form.

The norfloxacin metal complex is compounded with the polyenol to form a membrane structure, and the structure is preferably as follows: (Z)_z{X[MO(NF)_n]_mP represents a polyalkenol, preferably polyvinyl alcohol (PVA).

The norfloxacin metal complex and the polyene alcohol complex are prepared by the following method:

(1) preparing a polyalkene alcohol solution;

(2) preparing norfloxacin metal complexes according to the second aspect, and solutions thereof;

(3) preparing the norfloxacin metal complex and the polyene alcohol complex.

The norfloxacin metal complex provided by the invention has the following beneficial effects:

(1) the norfloxacin metal complex provided by the invention is rich in material structure, and the norfloxacin bioactivity is enhanced through the synergistic effect of norfloxacin and metal elements, so that the drug resistance of bacteria to drugs is reduced.

(2) The norfloxacin metal complex can be applied to surface bacteriostasis of various daily utensils, surface antibiosis of medical instruments, bacteriostasis by adopting various medicament formulations and the like, and has wide application range.

(3) The norfloxacin metal complex is loaded on a high polymer material, particularly a polyene alcohol material, and can achieve the long-acting slow-release antibacterial effect through the action of hydrogen bonds;

(4) the preparation method is simple, the raw materials are easy to obtain, and the method is easy to operate and is beneficial to industrial popularization.

Drawings

FIG. 1 shows the infrared spectra of the starting material norfloxacin and example 1;

FIG. 2 shows UV absorption spectra of example 2, comparative example 1, comparative example 2 and comparative example 3 in a scan range of 200 to 400 nm;

FIG. 3 shows UV absorption spectra at an excitation wavelength of 275nm for example 2, comparative example 1, and comparative example 2;

FIG. 4a is a graph showing the sustained-release antibacterial effect against E.coli of example 2(S) and comparative example 2 (D);

FIG. 4b is a graph showing the sustained-release antibacterial effects against Staphylococcus aureus in example 2(S) and comparative example 2 (D).

Detailed Description

The features and advantages of the present invention will become more apparent and appreciated from the following detailed description of the invention.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

According to a first aspect of the present invention, there is provided a norfloxacin metal complex which is prepared by complexing norfloxacin with a compound containing a metal element of the subgroup and a polyacid compound,

the norfloxacin metal complex structure can be represented as follows: (Z)_z{X[MO(NF)_n]_m}，

Wherein Z represents a cation, X represents a polyacid anion, and M represents a subgroup metal element; z is 1 to 4, preferably 1 to 3, such as 2; n is 1 to 4, preferably 1 to 3, such as 2; m is 1 to 4, preferably 1 to 3, such as 2.

In a preferred embodiment, the polyacid anion is a polyacid anion containing a transition metal element, preferably a gamma polyacid anion, more preferably a polyacid anion containing a group VIB metal element, especially preferably one of polyacid anions containing a chromium element, a molybdenum element or a tungsten element, and further preferably a polyacid anion containing a molybdenum element, such as [ gamma-Mo [ ]₈O₂₆]^4-。

In a preferred embodiment, X is polyacid anion containing molybdenum element, and the molybdenum element has anti-tumor activity, low toxicity and multi-valence state change, so that the complex has a richer structure.

In a preferred embodiment, M is a group VB metal element, preferably one of vanadium, niobium, and tantalum, and more preferably vanadium.

In a preferred embodiment, M is vanadium, which has anti-inflammatory, bactericidal and other biological activities, the physiological effect and toxicity of vanadium compounds are related to the total amount, chemical property and form of vanadium, and the vanadium compounds have the function of promoting the physiological functions of animals in a reasonable dosage range, such as maintaining the growth of organisms, promoting the absorption of glucose, exhibiting insulin-like effect and the like, and also have better biological activities after forming complexes with drug molecules, and can be used for diagnosing and treating certain diseases. Vanadium plays an important role in regulating blood sugar metabolism, urinary metabolism, cardiovascular metabolism and the like of the body.

In a preferred embodiment, Z is a metal cation or an ammonium ion, more preferably an ammonium ion (NH)₄ ⁺)。

In a preferred embodiment, the norfloxacin metal complex has a structure in which a polyacid anion is centered and linked to a complex of norfloxacin and an element of the subgroup metal through a terminal oxygen.

In a preferred embodiment, the norfloxacin metal complex coordinates to the subgroup metal element by chelating coordination with norfloxacin as an organic ligand.

In a preferred embodiment, the carboxyl group and the ketocarbonyl group of the norfloxacin molecule coordinate to the metal element of the subgroup, wherein the carboxyl group coordinates to the metal element in a monodentate manner.

According to a second aspect of the present invention, there is provided a process for preparing the norfloxacin metal complex described above, which comprises the steps of:

mixing Norfloxacin (NF), a compound containing an accessory group metal element and a polyacid compound, and optionally stirring;

in a preferred embodiment, the polyacid compound is a compound containing a transition metal element in a polyacid anion, preferably a compound containing a group VIB metal element in a polyacid anion, more preferably one of compounds containing a chromium element, a molybdenum element or a tungsten element in a polyacid anion, and even more preferably a compound containing a molybdenum element in a polyacid anion, such as (NH)₄)₆Mo₇O₂₄·4H₂O。

In a preferred embodiment, the polyacid compound is a templating agent, and is further capable of forming a complex structure centered on a polyacid anion.

In the present invention, the compound containing a group VB metal element is preferably a compound containing a group VB metal element, more preferably one of compounds containing a vanadium element, a niobium element, or a tantalum element, and particularly preferably a compound containing a vanadium element.

In a preferred embodiment, the compound containing a group b metal element is an oxide containing a group b metal element, preferably an oxide containing a group VB metal element, more preferably one of oxides containing a vanadium element, a niobium element, or a tantalum element, and particularly preferably an oxide containing a vanadium element, such as vanadium pentoxide.

In a preferred embodiment, the compound containing the metal element of the subgroup can be obtained by purchase or experiment, preferably by experiment, and the purity of the product is higher, so that the formation of the norfloxacin metal complex is facilitated.

In a preferred embodiment, the compound containing a group metal element is an oxide containing a group metal element, which is obtained from a corresponding group metal element-containing oxoacid salt, which is one of group VB metal element-containing oxoacid salts, preferably vanadium element-, niobium element-or tantalum element-containing oxoacid salts, more preferably vanadium element-containing oxoacid salts, such as ammonium metavanadate,

adding oxysalt containing the subgroup metal element into an optional heatable container, heating, optionally stirring, cooling after the reaction is finished to obtain oxide containing the subgroup metal element for later use, wherein,

the heatable container is preferably an evaporation dish, the heating mode is preferably sand bath heating, water bath heating, heating jacket heating or electromagnetic oven heating, and the like, and the sand bath heating is more preferred;

preferably, the molar ratio of the compound containing the subgroup metal element to the norfloxacin and polyacid compound is 1: 0.5-0.9: 0.2-0.45, such as 1:0.7: 0.35.

In a preferred embodiment, a solvent is also added in step (1), said solvent being preferably water, an organic solvent or a combination of both, more preferably a combination of water and an organic solvent, wherein,

the organic solvent is preferably methanol, ethanol, isopropanol, acetone, or the like, and is preferably ethanol.

In the invention, when the solvent is a composition of an organic solvent and water, the volume ratio of the organic solvent to the water is 1: 1-4, preferably 1: 1.5-3, and more preferably 1: 2.

In the invention, the weight volume ratio of norfloxacin to added solvent is (0.12-0.30) parts by weight: (10-30) parts by volume, more preferably (0.15-0.25) parts by weight: (12 to 20) parts by volume, for example, 0.22 part by weight: 15 parts by volume, wherein 1 part by weight based on 1g and 1 part by volume based on 1 mL.

In a preferred embodiment, a salt strong electrolyte solution, preferably a KCl solution or a NaCl solution, etc., more preferably a KCl solution, is also added in step (1).

Preferably, the concentration of the salt strong electrolyte is 1-4 mol.L^-1More preferably 1.5 to 3 mol.L^-1Such as 3 mol. L^-1。

In the invention, salt strong electrolyte is added to balance various electrolytes in the solution and keep relatively stable.

Preferably, the weight volume ratio of the norfloxacin to the salt strong electrolyte solution is (0.12-0.30) parts by weight: (1.6-4), more preferably (0.15-0.25) parts by volume: (2 to 3.2) parts by volume, e.g., 0.22 part by weight: 3 parts by volume, wherein 1 part by weight based on 1g and 1 part by volume based on 1 mL.

In a preferred embodiment, the mixture or its solution in step (1) is reacted at a set temperature with stirring, wherein

The set temperature is 15-35 ℃, preferably 20-30 ℃, and more preferably 25 ℃;

the stirring time is 1-4 h, preferably 1.5-3 h, and more preferably 2 h.

Step (2), adjusting the pH of the mixture or the solution thereof in the step (1) to acidity;

in a preferred embodiment, the pH is adjusted by using a weak acid, the weak acid is formic acid, acetic acid, benzoic acid, oxalic acid, etc., preferably acetic acid, and the concentration of the weak acid is 1 to 4mol · L^-1Preferably 1.5 to 3 mol.L^-1Such as 2 mol. L^-1。

In a preferred embodiment, the pH of the mixture or the solution thereof is adjusted to 3.5 to 5.5, preferably, to 4.

The inventor finds that both the piperazinyl group and the carboxyl group of norfloxacin are protonated at pH < 3, both the piperazinyl group and the carboxyl group are deprotonated at pH > 10, and the N atom of the piperazinyl group can participate in coordination of metal under neutral and weakly alkaline conditions, but the N atom of the piperazinyl group cannot participate in coordination of metal under weak acid conditions, so that the pH is preferably adjusted to 3.5-5.5.

In a preferred embodiment, the solution in step (2) is stirred at 15-30 ℃ for 10-60 min, preferably, the temperature is controlled at 20-25 ℃ for 1-1.5 h, and further, at 25 ℃ for 30 min.

Step (3), heating for reaction;

in a preferred embodiment, the solution obtained in step (3) is transferred to a reaction vessel, preferably a polytetrafluoroethylene low-pressure reaction kettle, and the reaction is carried out at a constant temperature under heating conditions.

In a preferred embodiment, the heating temperature is 100 ℃ to 150 ℃, preferably 110 ℃ to 130 ℃, and more preferably 120 ℃.

In a preferred embodiment, the reaction time is 2 to 5 days, preferably 4 days.

And (4) after the reaction is finished, carrying out post-treatment to obtain a target product.

In a preferred embodiment, the temperature is reduced after the reaction is complete, and the material after the reaction is reduced to a temperature of from 10 ℃ to 50 ℃, preferably from 15 ℃ to 40 ℃, more preferably from 20 ℃ to 35 ℃, e.g. 25 ℃.

In the present invention, the cooling method may be natural cooling or programmed cooling, preferably programmed cooling, and further preferably 5 to 20 K.h^-1The temperature reduction speed is preferably 8-15 Kh^-1More preferably 10 Kh^-1。

In a preferred embodiment, the product obtained after the temperature reduction is washed to remove soluble impurities that may be attached to the surface, and the washing liquid used for washing the solid is preferably distilled water.

In a preferred embodiment, after the product after temperature reduction is washed, it is dried, preferably by vacuum drying, atmospheric heating, natural drying, etc., more preferably by vacuum drying, to obtain the object product of the present invention, i.e., the norfloxacin metal complex, whose structure can be represented as follows: (Z)_z{X[MO(NF)_n]_mAnd (c) the step of (c) in which,

z is 1 to 4, preferably 1 to 3, such as 2; n is 1 to 4, preferably 1 to 3, such as 2; m is 1 to 4, preferably 1 to 3, such as 2.

Z represents a cation, preferably a metal cation or an ammonium ion, more preferably an ammonium ion;

x represents a polyacid anion, preferably a polyacid anion containing a transition metal element, more preferably a gamma-type polyacid anion, particularly preferably a polyacid anion containing a group VIB metal element, even more preferably one of polyacid anions containing a chromium element, a molybdenum element or a tungsten element, and most preferably a polyacid anion containing a molybdenum element, such as (gamma-Mo)₈O₂₆)^4-；

M represents a metal element of a subgroup, preferably M is a metal element of a VB group, more preferably one of a vanadium element, a niobium element and a tantalum element, and particularly preferably a vanadium element;

infrared spectroscopic analysis shows that the absorption peaks of the complex and the ligand norfloxacin are different, and NF is 1730cm^-1The characteristic stretching vibration absorption peak (v) of carboxyl group appears_C＝O) After the complex is formed, the absorption peak disappears at 1556cm^-1、1393cm^-1Absorption peaks corresponding to asymmetric stretching vibration and symmetric stretching vibration of carboxyl group appeared, indicating that carboxyl group on carbostyril ring in NF coordinates with vanadium in monodentate manner, NF was in 1622cm^-1The absorption peak (C ═ O) appears in the position, and after the complex is formed, the absorption peak is red-shifted to 1630cm^-1Here, it is shown that the carbonyl group also participates in the coordination. Further, when X is (γ -Mo)₈O₂₆)^4-Then, the resulting complexThe infrared spectrum of the infrared spectrum is 945cm^-1、856cm^-1、791cm^-1Has a characteristic absorption peak which can be assigned as gamma-Mo₈O₂₆Vibration absorption peaks of ν (Mo ═ O) and ν (Mo-O-Mo) in the structure;

the complex is at 3440cm^-1Nearby also shows H₂Strong stretching vibration absorption peak of O

Therefore, the norfloxacin metal complex of the invention is 1556cm^-1、1393cm^-1、1630cm^-1、945cm^-1、856cm^-1、791cm^-1And 3440cm^-1There is an absorption peak.

In the invention, the norfloxacin and the metal ions have a synergistic effect, so that the antibacterial activity of the complex is stronger than that of norfloxacin, thereby remarkably improving the biological activity of the drug and further reducing the drug resistance of bacteria to the drug.

According to a third aspect of the present invention there is provided the use of a norfloxacin metal complex as described above, especially for antibacterial applications.

The antibacterial agent is preferably in vitro antibacterial, and is more preferably used for surface bacteriostasis of various daily utensils, surface antibiosis of medical instruments, bacteriostasis by adopting various medicament formulations and the like.

In application, the norfloxacin metal complex can also be compounded with polyenol to form a membrane structure.

The structure is preferably as follows: (Z)_z{X[MO(NF)_n]_m-P, wherein P represents a polyalkenol, preferably polyvinyl alcohol (PVA);

the above complex can be prepared according to the following method:

(1) preparation of Polyethanolic solution

Dissolving the polyenol in a solvent, preferably distilled water, heating while stirring to completely dissolve the polyenol, preferably at a temperature of 70-120 ℃, more preferably 80-100 ℃, such as 90 ℃.

In a preferred embodiment, the polyvinyl alcohol is preferably polyvinyl alcohol, which is a safe biodegradable high molecular organic substance, has no toxicity or side effect on human body, has good biocompatibility, good adhesive strength, easy film formation, and excellent mechanical properties of the film, and the tensile strength is enhanced along with the increase of polymerization degree and alcoholysis degree.

In a preferred embodiment, the weight/volume ratio of the above-mentioned polyenol to the solvent is (1 to 5 parts by weight), (10 to 50) parts by volume, more preferably (1.5 to 3) parts by weight, (15 to 30) parts by volume, such as 2 parts by weight: 20 parts by volume, wherein 1 part by weight is based on 1g and 1 part by volume is based on 1 mL.

In a preferred embodiment, the polyalkenol solution is treated with mechanical agitation or ultrasonic agitation, preferably ultrasonic agitation, to remove air bubbles from the solution, when the solution is in a gelatinous transparent state, as the polyalkenol is completely dissolved.

(2) Preparing a norfloxacin metal complex according to the second aspect described above, and a solution thereof;

in a preferred embodiment, the obtained norfloxacin metal complex is dissolved in a solvent, and the solvent is preferably distilled water and uniformly mixed;

in a preferred embodiment, the weight/volume ratio of the norfloxacin metal complex to the solvent is (0.0080-0.020) parts by volume (2-6), more preferably (0.0100-0.0015) parts by volume (2-4), such as 0.0126 part by volume to 3 parts by volume, wherein 1 part by weight is based on 1g and 1 part by volume is based on 1 mL.

Preferably, the solution is mixed well and uniformly by adopting a mechanical stirring mode or an ultrasonic oscillation mode, and more preferably, the ultrasonic oscillation mode is adopted

Preferably, the mixing time is preferably 1-5 h, more preferably 2-4 h, such as 3h, so that the norfloxacin metal complex is uniformly dispersed in the solvent;

(3) preparation of the Compound (Z)_z{X[MO(NF)_n]_m}-P

Mixing the solution prepared from the norfloxacin metal complex with a polyene alcohol solution;

in a preferred embodiment, the polyalkene alcohol solution prepared in the step (1) is added into the norfloxacin metal complex solution prepared in the step (2), and stirred, preferably vigorously stirred for 1-4 h, more preferably 1.5-3 h, such as 3h, so as to uniformly mix the two;

in a preferred embodiment, the volume ratio of the norfloxacin metal complex solution to the polyvinyl alcohol solution measured in the step (3) is 1 (0.5-2), and more preferably 1: (0.8-1.5), such as 1: 1;

in a preferred embodiment, the mixed solution of the norfloxacin metal complex solution and the polyvinyl alcohol solution is treated by a mechanical stirring method or an ultrasonic oscillation method, preferably an ultrasonic oscillation method, to remove air bubbles in the mixed solution.

In a preferred embodiment, the mixed solution is subjected to film formation;

in a preferred embodiment, the mixed solution obtained above is dried to form a film, preferably, the mixed solution is poured into a film forming container and then dried to form a film, and further, the drying treatment is performed by using a vacuum drying method, an atmospheric heating method, a natural drying method, or the like, and more preferably, a vacuum drying method is used.

In a preferred embodiment, the drying is performed at 40 ℃ to 80 ℃, more preferably at 45 ℃ to 60 ℃, such as 50 ℃, and further, the drying time is preferably 1 to 4 hours, more preferably 1.5 to 3 hours, such as 2 hours.

Further, the film forming container is preferably a glass container, a plastic container or the like, more preferably a plastic container such as a 96-well circular plate cap.

In a preferred embodiment, the dry formed composite film, which may be designated as (Z), is peeled off and collected for use_z{X[MO(NF)_n]_mP, as described above.

The composite membrane has a slow release effect, and can reduce the release rate of the norfloxacin metal complex, so that the drug release speed is stable, the drug effect is improved, and the drug administration times are reduced.

In the present invention, the inventors consider that (Z)_z{X[MO(NF)_n]_mNitrogen on the piperazinyl group of norfloxacin in the formula can form hydrogen bonds with hydroxyl groups on the surface of PVA, and polyacid anionsThe oxygen atom on the poly (vinyl alcohol) may form a hydrogen bond with a hydroxyl group on the surface of the poly (vinyl alcohol), and (Z) may be decreased_z{X[MO(NF)_n]_mThe release rate from the polyenol is increased, so that the sustained release effect is achieved.

Examples

Example 1

Adding 0.085mol of ammonium metavanadate solid into an evaporation dish, heating the evaporation dish on a sand bath, continuously stirring the mixture, and stopping heating until white solids are all changed into reddish brown solids to obtain a product vanadium pentoxide (V)₂O₅) And cooling for later use.

1.00mmol of the vanadium pentoxide obtained above, 0.70mmol of Norfloxacin (NF) and 0.35mmol of (NH)₄)₆Mo₇O₂₄·4H₂O, and 3ml KCl (3 mol. L) is added^-1) Adding 10mLH₂O and 5mL of ethanol, and stirred at room temperature for 2 h.

With 2 mol. L^-1The HAc solution was adjusted to pH 4.0 and stirring was continued at room temperature for 0.5h

And transferring the uniformly stirred turbid solution into a 25mL polytetrafluoroethylene low-pressure reaction kettle, and reacting at constant temperature of 120 ℃ for 4 days.

At 10 K.h^-1The temperature is reduced to room temperature in a programmed way. Green massive crystals were obtained. Washing with distilled water, and drying in vacuum drying oven to obtain product (NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂The complex, in 34% yield (in V), was diffracted by X-ray single crystal as described in experimental example 1.

Measurement using elemental Analyzer (NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂The C, H and N elements in the structure of the complex are measured as follows: c29.30, N7.41 and H2.98 are well matched with theoretical calculated values of C29.26, N7.47 and H2.92.

Measurement of norfloxacin starting Material and (NH) obtained in this example₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂Complex infrared spectrogram with measuring range of 4000～500cm^-1The results are shown in fig. 1, in which,

curve a shows the infrared spectrum of a sample prepared from the raw material norfloxacin;

curve b shows the infrared spectrum of the sample obtained in example 1.

As can be seen from fig. 1:

norfloxacin concentration at 1730cm^-1The characteristic stretching vibration absorption peak (v) of carboxyl group appears_C＝O) Disappeared in example 1;

and the vibration peaks of the carboxyl groups of the sample 1 are respectively positioned at 1556cm^-1And 1393cm^-1. The difference between the two is 163cm^-1Because the difference is less than 200cm^-1It is demonstrated that the carboxyl group on the quinolone ring in NF coordinates to vanadium in a monodentate manner;

NF raw material 1622cm^-1The 3-position carbonyl stretching vibration absorption peak (C ═ O) appeared in (A), and was red-shifted to 1630cm in example 1^-1Here, it is shown that the carbonyl group also participates in the coordination;

furthermore, example 1 is located at 945cm^-1、856cm^-1、791cm^-1The characteristic absorption peak of (A) can be assigned as gamma-Mo₈O₂₆Vibration absorption peaks of ν (Mo ═ O) and ν (Mo-O-Mo) in the structure; example 1 at 3440cm^-1Nearby also shows H₂A strong stretching vibration absorption peak of O;

the existence and the variation trend of the characteristic absorption peak of the infrared spectrum indicate that the metal complex with NF and the polyacid compound exist in the structure.

Example 2

2.0g of polyvinyl alcohol (PVA) was added to 20.0mL of distilled water, and the mixture was heated and stirred at 90 ℃ until the solid PVA was completely dissolved and the solution was in a gelatinous transparent state, and then all the air bubbles were removed by ultrasonic oscillation to form a polyvinyl alcohol solution. The concentration of the PVA solution obtained at this time was 10%.

0.0126g of (NH) prepared in example 1 are taken₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂Adding 3mL of distilled water, carrying out ultrasonic oscillation for 3h, and dispersing uniformly to form norfloxacin metal complex solution。

Adding 3mL of the prepared polyvinyl alcohol solution into the norfloxacin metal complex solution, stirring vigorously for 2h, and then performing ultrasonic oscillation to remove all bubbles in the mixed solution.

Using the round groove of 96-hole plate cover as template, injecting 30 mul of mixed solution into the groove, vacuum drying at 50 deg.C for 2h, taking out, and drying to obtain the final product ((NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂h-PVA) and then peeled off the well plate and collected for use.

Comparative example

Comparative example 1

2.0g of polyvinyl alcohol (PVA) is weighed, 20.0mL of distilled water is added, the mixture is heated and stirred at 90 ℃ until the solid PVA is completely dissolved, the solution is in a colloidal transparent state, and then all bubbles are removed by adopting an ultrasonic oscillation method, so that the polyvinyl alcohol solution is formed. The concentration of the PVA solution obtained at this time was 10%.

3mL of distilled water was weighed, 3mL of the polyvinyl alcohol solution prepared above was added, and the mixture was vigorously stirred for 2 hours, after the polyvinyl alcohol was uniformly dispersed, ultrasonic oscillation was performed to remove all air bubbles in the mixed solution.

And (3) taking a circular groove of a 96-hole plate cover as a template, injecting 30 mu l of mixed solution into the groove, carrying out vacuum drying at 50 ℃ for 2h, taking out, peeling the dried and formed polyvinyl alcohol film from the hole plate, and collecting for later use.

Comparative example 2

2.0g of polyvinyl alcohol (PVA) is weighed, 20.0mL of distilled water is added, the mixture is heated and stirred at 90 ℃ until the solid PVA is completely dissolved, the solution is in a colloidal transparent state, and then all bubbles are removed by adopting an ultrasonic oscillation method, so that the polyvinyl alcohol solution is formed. The polyvinyl alcohol solution thus obtained had a concentration of 10%.

Weighing 0.0066g of norfloxacin, adding 3mL of distilled water, and carrying out ultrasonic oscillation for 3h to uniformly disperse norfloxacin in the aqueous solution to form norfloxacin solution.

3mL of the polyvinyl alcohol solution prepared above was added to the norfloxacin solution prepared above, and stirred vigorously for 2 hours to ensure that the norfloxacin aqueous solution and PVA could be mixed uniformly, followed by ultrasonic oscillation to remove all air bubbles from the mixed solution.

And taking a circular groove of a 96-hole plate cover as a template, injecting 30 mu l of mixed solution into the groove, carrying out vacuum drying at 50 ℃ for 2h, taking out, stripping the dried and formed composite membrane (NF-PVA) from the hole plate, and collecting for later use.

Comparative example 3

The procedure was identical to that of comparative example 2, except that the starting material used was not norfloxacin but (NH)₄)₆Mo₇O₂₄·4H₂O, thereby obtaining (NH)₄)₆Mo₇O₂₄·4H₂O solution, and subsequent reaction to obtain Mo₈O₂₆]^4--a PVA composite film.

Examples of the experiments

X-ray single crystal diffraction of sample of Experimental example 1

The sample used in this example was the sample prepared in example 1.

The X-ray single crystal diffraction data of the sample is Mo Kalpha ray on Agilent Super Nova type CCD X-ray single crystal diffractometer with multilayer film

Diffraction data were collected as incident radiation at a temperature of 293K.

Collected data are corrected by LP factor and empirical absorption, the structure is analyzed by using a SHELXTL software package by adopting a direct method, the optimization is carried out by a full matrix least square method, and all non-hydrogen atom coordinates are corrected by adopting anisotropic thermal parameters. The hydrogen atom coordinates on the organic group are obtained by a geometric hydrogenation method, wherein,

the crystallographic data of the samples are shown in table 1:

TABLE 1

^aR₁＝Σ||F_o|-|F_c||/Σ|F_o|,^bwR₂＝[Σ[w(F_o ²-F_c ²)²]/Σw(F_o ²)²]

Bond length of sample

And key angle (°) are as shown in table 2:

TABLE 2

As can be seen from the analysis of tables 1 and 2,

EXAMPLE 1 Synthesis of 2 mononuclear vanadium complexes (V-NF for short)₂) 1 piece of [ gamma-Mo ]₈O₂₆]^4-(abbreviation of. gamma. -Mo)₈) Polyacid anion and 2 NH₄ ⁺And (3) cation composition.

In mononuclear vanadium complexes V-NF₂In the structure, V forms a twisted { VO with 2 norfloxacin 4-carbonyl oxygen and hydroxyl oxygen on 3-carboxylic acid respectively through chelating coordination₆Octahedra wherein V ═ O bonds have bond lengths of

And the bond length of the other V-O bond is located at a distance

Within the range.

Polyanion gamma-Mo₈Comprises six { MoO₆Octahedron and two { MoO }₅Tetragonal pyramid, in which the lattice structure is at { MoO }₆The distance of the Mo-O bond in the octahedral structure is located

In the meantime.

Two groups of { MoO₆The octahedron is respectively connected with two { MoO }₅The tetragonal pyramids are connected by common edges to form alternating six-membered rings. In the presence of gamma-Mo₈The unit contains 14 terminal oxygens (O)_t) 6 double bridge oxygen (. mu.) of₂-O), 4 triple-bridged oxygens (μ)₃-O) and 2 four-bridged oxygens (. mu.g)₄-O)。Mo-O_tHas an average bond length of

In the meantime. Mo-O_bHas an average bond length of

In the meantime. Gamma-Mo₈Respectively passing two mu atoms of vanadium through₂the-O bond constituted the unit structure of example 1 in which the bond angle of Mo-O-V was 147.3(5)^°. The overall structure of the complex is gamma- [ Mo₈O₂₆]^4-The two ends of the vanadium-norfloxacin complex are connected with vanadium atoms on two vanadium-norfloxacin complexes respectively through terminal oxygens at symmetrical positions to form a sandwich structure.

Each unit molecule of example 1 was purified by gamma-Mo₈The terminal oxygen forms a 1D organic supermolecule chain along the b axis in space through a hydrogen bond (O1-H.N 3, O17-H.N 6) formed by the terminal oxygen and a nitrogen atom on a norfloxacin molecular piperazine ring, and on the other hand, the 1D chain forms a pi.pi.pi.stacking effect between NF ligands, and the distance between the centers of two aromatic rings is equal to

A 2D molecular network structure is formed in space.

Experimental example 2 measurement of antibacterial Properties of samples

The samples used in this example were those prepared from example 1 and the starting material norfloxacin.

The antibacterial performance test of the sample adopts a paper method, the test method refers to the national standard test method, the bacteriostasis rates of the sample on escherichia coli and staphylococcus aureus are respectively measured, the results are shown in tables 3 and 4,

TABLE 3 example 1 and raw material NF bacteriostasis rate to E.coli

Table 4 example 1 and raw material NF bacteriostatic ratio against staphylococcus aureus

Sample (I)	1 st time	2 nd time	3 rd time	Average number of colonies	Rate of inhibition of bacteria
						Blank space	135	128	131	131	----
Feedstock NF	10	12	11	11	91.6
						Example 1	14	13	13	13	90.1

The inhibition rate is (number of blank colonies-number of experimental colonies)/(number of blank colonies).

It can be seen that the antibacterial activity of example 1 is similar to that of norfloxacin, but the complex prepared in example 1 has a richer structure.

Experimental example 3 ultraviolet-visible Spectroscopy of samples

The samples used in this experimental example were those prepared in example 2, comparative example 1, comparative example 2 and comparative example 3.

An UV2550 ultraviolet visible spectrophotometer is adopted, quartz is used as a substrate to measure the ultraviolet spectrum of the composite film, the scanning range is 200-400 nm, the result is shown in figure 2, wherein,

curve a shows the uv absorption spectrum of the sample obtained in example 2;

curve b shows the uv absorption spectrum of the sample prepared in comparative example 1;

curve c shows the uv absorption spectrum of the sample prepared in comparative example 2;

curve d shows the uv absorption spectrum of the sample prepared in comparative example 3.

As can be seen from the figure 3 of the drawings,

the main absorption bands of comparative example 2(NF-PVA composite film) were 321nm and 335nm for example 2 ((NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂} -PVA composite membranes), whether the position, intensity or shape of the maximum absorption peak is very similar to that of NF-PVA composite membranes, and obviously the absorption band should be assigned as the pi → pi + transition of NF;

compared with the comparative example 2, the maximum absorption of the example 2 is slightly purple shifted, and the inventor believes that the ligand NF is a macrocyclic molecule, and the ligand NF is coordinated with vanadium ions to ensure that the molecule is not positioned on the same plane, so that the flatness of the molecule is reduced, and the conjugation is reduced; meanwhile, vanadium ions have a certain attraction effect on large pi bonds, and after coordination, the electron cloud on the ring moves to the vanadium ions, so that the charge on the ring is unevenly distributed, the symmetry is reduced, the conjugation of the ring is correspondingly reduced, and the wavelength is subjected to purple shift;

in addition, example 2 exhibited a new characteristic absorption peak around 201nm, which is more consistent with the characteristic absorption of comparative example 3 at that point.

In conclusion, the raw materials Norfloxacin and (NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂Successfully loaded on the PVA film.

Experimental example 4 in vitro measurement of sustained Release behavior of sample

The samples used in this experimental example were those prepared in example 2, comparative example 1 and comparative example 2.

The sustained release effect of the composite membrane was monitored by measuring the cumulative amount of the compound released during each time period.

The operation method comprises the following steps: 10 samples prepared in example 2, comparative example 1 and comparative example 2 are respectively placed in a 20mL beaker, 10mL of distilled water is added, the membrane is taken out after being soaked for 3h at 37 ℃, the membrane is placed in a new 20mL beaker again, 10mL of distilled water is added, the membrane is taken out after being continuously soaked for 3h at 37 ℃, the operation is carried out once every 3h in the first 12h, and the sampling is repeated every 12h within 12 h-48 h. The sampled solutions were collected and subjected to uv absorbance test at an excitation wavelength of 275nm, and the results are shown in fig. 3, in which,

curve a shows the uv absorption spectrum of the sample obtained in example 2;

curve c shows the uv absorption spectrum of the sample prepared in comparative example 2.

As can be seen from the figure 3 of the drawings,

the cumulative release of comparative example 2 reached 91% within 0h to 9h, and after 9h, the release of NF in aqueous solution was almost unchanged, indicating that there was a burst release process of NF within the first 9h, during which the cumulative release of NF reached the maximum, and after 9h, the release of NF was close to zero;

the burst release process of example 2 is within 0h to 12h, the maximum release in the process is about 28%, and the cumulative release reaches 72%. A slow release process is carried out between 12h and 48h, the release cumulant is kept between 10 percent and 13 percent,

and in example 2, the activity is still maintained after 48 hours, and the bacteriostasis rate is maintained at 32%.

Example 2 has a slower release profile in aqueous solution than comparative example 2 (0h-48 h).

Overall, example 2 ((NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂} -PVA composite film) in an aqueous solution, the inventors believe, without being bound by any theory, that the structure of example 2 contains a polyacid group [ gamma-Mo ]₈O₂₆]^4-The polyacid surface contains a large number of oxygen atoms, which makes gamma-Mo₈Having an oxygen-rich structure, except for the nitrogen of the piperazinyl group of norfloxacin, gamma-Mo₈The oxygen atom on the PVA can also form a large number of hydrogen bonds with the oxygen atom on the surface of the PVA, and the (NH) is reduced₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂The rate of release from PVA such that (NH)₄)₂{(γ-Mo₈O₂₆)[VO(NF)₂]₂Significantly reduced solubility in aqueous solutionsLow, thereby achieving the slow release effect.

Experimental example 5 in vitro measurement of sustained-Release antibacterial Activity of sample

The samples used in this experimental example were those prepared in example 2 and comparative example 2.

The bacteriostatic activity test of the composite membrane adopts a paper sheet method, and the composite membrane replaces paper sheets to carry out experimental operation, wherein,

FIG. 4a shows the slow-release antibacterial effect against E.coli of example 2(S) and comparative example 2 (D);

FIG. 4b shows the sustained release antibacterial effects against Staphylococcus aureus in example 2(S) and comparative example 2 (D).

As can be seen from FIG. 4a, the bacteriostatic diameters of example 2 and comparative example 2 for E.coli were 25mm and 31mm, respectively (PVA film had no bacteriostatic effect, and the diameter after water-absorbing swelling was 11 mm).

To further compare the antibacterial activity of example 2 and comparative example 2, three cycles of testing were again performed.

As shown in FIG. 4 aII, in II, the inhibition diameters of example 2 and comparative example 2 for Escherichia coli are 29mm and 27mm respectively, compared with I, the inhibition diameter of comparative example 2 is reduced by 13%, and the inhibition diameter of example 2 is increased by 16%;

in III, the inhibiting diameter of the comparative example 2 for the escherichia coli is the same as that of the PVA film, namely zero, while the inhibiting diameter of the example 2 for the escherichia coli is reduced by 20% compared with II;

in IV, the inhibition diameter (14nm) of example 2 for Escherichia coli is reduced by 39% compared with III, and the reduction trend is relatively slow.

The invention has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to be construed in a limiting sense. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, which fall within the scope of the present invention. The scope of the invention is defined by the appended claims.

Claims

1. The norfloxacin metal complex is characterized by being prepared by compounding norfloxacin, a compound containing a subgroup metal element and a polyacid compound, and the complex structure is represented as follows: (Z)_z{X[MO(NF)_n]_mWherein Z is an ammonium ion and X represents a molybdenum-containing compoundγPoly (acid) anion [ alpha ], [ beta ], [ alpha ], [ beta ] or a mixture of thereofγ-Mo₈O₂₆]^4-M is vanadium, NF is norfloxacin, z is 2, n is 2, and M is 2.

2. A process for the preparation of norfloxacin metal complexes according to claim 1, characterized in that it comprises the steps of:

(1) mixing norfloxacin, a compound containing an accessory group metal element and a polyacid compound, and optionally stirring;

(2) adjusting the pH of the mixture or a solution thereof to acidity;

(3) heating to react;

3. The production method according to claim 2, characterized in that, in the step (1),

the compound containing the subgroup metal element is an oxide containing vanadium element,

the polyacid compound is polyacid anion containing molybdenum element,

the molar ratio of the compound containing the subgroup metal element to the norfloxacin and polyacid compound is 1: 0.5-0.9: 0.2-0.45.

4. The production method according to claim 3, characterized in that, in the step (1),

the compound containing the metal element of the secondary group is vanadium pentoxide;

the polyacid compound is (NH)₄)₆Mo₇O₂₄·4H₂O。

5. The production method according to claim 2,

in the step (1), the step (c),

adding salt strong electrolyte solution which is KCl solution or NaCl solution,

adding a solvent, wherein the solvent is a composition of water and an organic solvent, and the organic solvent is methanol, ethanol, isopropanol or acetone.

6. The production method according to claim 2,

in the step (2), the pH is adjusted by adopting weak acid, wherein the weak acid is formic acid, acetic acid, benzoic acid or oxalic acid, and the pH of the mixture or the solution thereof is adjusted to 3.5-5.5.

7. The production method according to claim 2,

and (4) cooling after the reaction is finished, and adopting natural cooling or programmed cooling.

8. The method according to claim 7, wherein the temperature is lowered by a programmed cooling process at 5-20 Kh in step (4)^-1The speed is programmed to reduce the temperature; cooling to 10-50 ℃.

9. The method according to claim 7, wherein the temperature is lowered by a programmed cooling process at 8-15 Kh in step (4)^-1The speed is programmed to reduce the temperature; cooling to 15-40 ℃.

10. The use of the norfloxacin metal complex of claim 1 for preparing an antibacterial agent for daily ware surface bacteriostasis, medical device surface bacteriostasis and in pharmaceutical dosage forms.

11. The use of claim 10, wherein the norfloxacin metal complex is complexed with a polyenol and has the structure: (Z)_z{X[MO(NF)_n]_m-P, P representing a polyenol.

12. Use according to claim 11, characterized in that the norfloxacin metal complex is complexed with a polyenol to form a film structure, P being a polyvinyl alcohol.

13. Use according to claim 11, characterized in that the norfloxacin metal complex and the polyenol complex are prepared as follows:

(1) preparing a polyalkene alcohol solution;

(2) preparation of norfloxacin metal complexes according to one of claims 2 to 9, and solutions thereof;

(3) preparing the norfloxacin metal complex and the polyene alcohol complex.