Livallaryl group internal rotation functional molecule as well as preparation method and application thereof

Abstract

The invention provides a lily aldehyde group internal rotation functional molecule as well as a preparation method and application thereof, and belongs to the technical field of food gelling degree analysis and detection. The convallaria majalis aldehyde group internal rotation functional molecule is obtained through conjugate coupling of a post-synthesized convallaria majalis extract and a post-synthesized natural extract minoxidil. The lily aldehyde group internal rotation functional molecule (BPMPPO) provided by the invention has a conjugated single-double bond internal rotation structure, can present different rotation states in fluid atmospheres with different microcell viscosities, and is further converted into an optical signal to be released, so that rapid, efficient and visual detection of the food gelling degree is realized, and the detection sensitivity is high. The method is particularly suitable for detecting the gelling degree of fluid food containing a large number of pseudoplastic components, the gelling degree can be visually presented in situ according to the strength of surface sightseeing signals, and measurement can be completed without a mechanical shearing process.

Description

Technical Field

[0001] The present invention relates to the technical field of food gelation degree analysis and detection, in particular to a lilysinal-based internal rotation functional molecule and a preparation method and application thereof. Background Art

[0002] Food gum is a type of food thickener that not only stabilizes the physical structure of each component of food, but also has the effect of flocculation and emulsification. Various types of food gum are usually required in the processing process to enhance the viscosity and taste of food. Therefore, the degree of food gelation is an effective measure to evaluate the viscosity of food gum. Generally, food gum is a mixture of polysaccharides, proteins and natural plant extracts, and is widely used in the food industry. As a type of high-value-added functional additive for flowable foods, it is commonly found in flowing fluids. The relative viscosity of the main ingredients can be controlled by controlling the ratio of the main ingredients. The effect on the degree of gelation of food also varies greatly, thereby meeting the application needs of different occasions. Food glues with high viscosity are easier to bond and shape, and have a more significant body, which effectively improves their texture and taste. Overall, the degree of gelation of the food is higher, but their fluidity is poor, and their wettability and spreadability are also poor, and their solubility and permeability are also poor. In contrast, food glues with low viscosity have better fluidity, better spreadability and permeability, and strong wetting ability. However, their texture and taste may be slightly worse, their body may be lower, and their shaping ability is poor, resulting in a low degree of gelation of the food overall. In order to improve the formulation process of food glues in a more targeted manner, in order to meet customer needs for food glues with different micro-area viscosities and improve the degree of gelation of food, it is imperative to develop a measurement tool that can achieve rapid, in-situ, and visual measurement of its micro-area viscosity.

[0003] In the field of fluid food analysis and testing, photochemical technology can leverage molecular tools to perform real-time, in-situ, and visual measurements of micro-region viscosity in food gels. This static light response method effectively avoids the errors caused by traditional shear thinning and can effectively circumvent the consumption of large amounts of sample, simplifying testing procedures and saving testing time, thereby improving the control of the degree of gelation in fluid foods. Therefore, those skilled in the art urgently need to develop a molecular tool suitable for testing the degree of gelation in fluid foods. Summary of the Invention

[0004] The purpose of the present invention is to provide a lilysinal-based internal rotation functional molecule and its preparation method and application, so as to solve the technical problems of the existing method for detecting the degree of gelation of food, such as the high sample amount required and the complex detection method.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a lily of the valley aldehyde-based internal rotation functional molecule, named 2,6-bis((3-4-(tert-butyl)phenyl)-2-methylpropylene)amino-4-(piperidin-1-yl)pyrimidine-1-oxide;

[0007] Its structural formula is shown below:

[0008]

[0009] The present invention provides a method for preparing a lily of the valley aldehyde-based internal rotation functional molecule, comprising the following steps:

[0010] Step 1), mixing lily of the valley aldehyde and solvent 1 to obtain a lily of the valley aldehyde solution; mixing an organic base and solvent 2 to obtain an organic base solution; mixing minoxidil and solvent 3 to obtain a minoxidil solution;

[0011] Step 2), mixing the lilysinaldehyde solution and the organic base solution to obtain a mixed solution, adding the minoxidil solution, and then performing a conjugated coupling reaction to obtain a reaction solution containing a lilysinaldehyde internal rotation functional molecule;

[0012] Step 3) extracting, purifying, recrystallizing and drying the reaction solution containing the lily of the valley aldehyde internal rotation functional molecule in sequence to obtain the lily of the valley aldehyde internal rotation functional molecule.

[0013] Furthermore, in step 1), the concentration of the lilysaldehyde solution is 2-4 mol / L, the concentration of the organic base solution is 1-8 mol / L, and the concentration of the minoxidil solution is 1-3 mol / L.

[0014] Furthermore, in step 1), the organic base includes one or more of triethylamine, trimethylamine, N,N-diisopropylethylamine, pyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine, lithium diisopropylamide, sodium bis(trimethylsilyl)amide, sodium tert-butoxide, potassium tert-butoxide and N,N,N',N'-tetramethylethylenediamine;

[0015] The solvent 1 includes one or more of methanol, acetonitrile, tetrahydrofuran, ethanol, N,N-dimethylformamide, ethyl acetate and dimethyl sulfoxide;

[0016] The second solvent and the third solvent independently include one or more of methanol, ethanol, propylene glycol, ethylene glycol, isopropanol, n-butanol and cyclohexanol.

[0017] Furthermore, in step 1), when the lilysulphide and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 h;

[0018] When the organic base and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 h;

[0019] When the minoxidil and the second solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 hour.

[0020] Furthermore, the molar ratio of minoxidil to organic base is 1:2-8;

[0021] The molar ratio of minoxidil to lilyral is 1:2-4.

[0022] Furthermore, in step 2), the mixing temperature is 23 to 34° C., and the mixing time is 0.5 to 2 h;

[0023] The mixing is carried out under stirring conditions at a rate of 900 to 1800 rpm;

[0024] The minoxidil solution is added under heating conditions, the heating rate is 1 to 5°C / min, and the minoxidil solution is added at a rate of 5 to 20 mL / min;

[0025] The temperature of the conjugation coupling reaction is 70-110° C., and the time is 1-24 hours.

[0026] The present invention also provides an application of a lily of the valley aldehyde-based internal rotation functional molecule in detecting the degree of gelation of food. The lily of the valley aldehyde-based internal rotation functional molecule, a solvent, and a test sample are mixed to obtain a mixed solution. The intensity of the light signal released by the mixed solution at 420-750 nm is detected, and the degree of gelation of the food sample to be tested is calculated based on a standard curve of the light signal intensity and viscosity.

[0027] Furthermore, the usage ratio of the lily of the valley aldehyde internal rotation functional molecule, the solvent and the test sample is 1-100 μmol:1L:0.005L.

[0028] Furthermore, the solvent includes one or more of ethyl acetate, fructose and triacetin;

[0029] The sample to be tested includes one or more of glycerol, food gel, food jelly, fluid food and liquid food.

[0030] Beneficial effects of the present invention:

[0031] (1) The lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO) provided by the present invention is obtained by further conjugating and coupling a post-synthetic natural lily of the valley extract - lily of the valley aldehyde and a post-synthetic natural extract - minoxidil, thereby realizing the effective construction of an organic internal rotation functional molecule with a conjugated effect. The required raw materials are widely present in the plant kingdom and are abundant in source, which expands the application scope of traditional natural products in the field of internal rotation functional molecules and realizes high-value interdisciplinary and cross-field development and application. The overall application preparation cost is low, the amount used is at the milligram level, the application cost is low, and it has good sustainable green environmental protection characteristics. In addition, the preparation process adopts a one-step preparation method, which avoids the solvent consumption and yield reduction in the complicated preparation process, and meets the fast requirements of large-scale manufacturing.

[0032] (2) The lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO) provided by the present invention has a flexible conjugated internal rotation structure. It will show different degrees of internal rotation characteristics in different food gel micro-area environments. It can rotate freely in the test sample with low gelation degree, and the dissipation is mainly through mechanical rotation, and the light signal is weak. In contrast, the rotation is inhibited in the test sample with high gelation degree, and the excited state ability is mainly dissipated through radiation transition. Strong light signal is released. According to different light signal intensities, effective measurement of different food gelation degrees can be achieved. The specific luminescence principle is as follows: Figure 1 As shown in the figure, the lilysinaldehyde-based internal rotation functional molecule, as a molecular-level measurement tool, can produce optical signals of varying intensities depending on the viscosity of the microregion when added to food gels. This can be used to determine the degree of gelation in the food. Stronger optical signals indicate a higher degree of gelation and reduced fluidity. Weaker optical signals indicate a lower degree of gelation and increased fluidity. BPMPPO is highly sensitive to the degree of gelation in food microregions, with a very high sensitivity coefficient (x = 0.68). Its chemical structure is relatively stable, allowing it to persist in complex food environments for long periods. Its color peak wavelength is 513 nm, a typical bright green light with a strong visual effect. Furthermore, this molecular tool exhibits excellent pH and solvent polarity tolerance and good photostability. It also has a low detection limit (as low as 1.05 cP), making it suitable for sensing changes in food gelation under minimal perturbations.

[0033] (3) After the lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO) provided by the present invention is added, it can be used as a molecular tool to measure the degree of food gelation in situ. During the measurement process, there is no need to use rotation or shear stress to perceive the change in the degree of food gelation. It can also avoid the shear thinning phenomenon caused by the shearing process of gelled foods containing a large amount of pseudoplastic components. At the same time, it can avoid the adverse effects of the destruction and distortion of the food gel microenvironment caused by shearing. The entire process can be measured in a relatively static state. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a diagram showing the mechanism of using lily of the valley aldehyde internal rotation functional molecules for the measurement of food gelling agents;

[0035] Figure 2 This is a high-resolution mass spectrum of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1;

[0036] Figure 3 This is the nuclear magnetic resonance spectrum of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1;

[0037] Figure 4 Spectra of the lilysinaldehyde-based internal rotation functional molecule prepared in Example 1 in solutions of different viscosities;

[0038] Figure 5 This is a linear fitting graph between the optical signal intensity and solution viscosity of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1;

[0039] Figure 6 Spectra of the lilysinaldehyde-based internal rotation functional molecule prepared in Example 1 in solutions with different pH values;

[0040] Figure 7 The photostability test results of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1 in glycerol and purified water are shown;

[0041] Figure 8 The absorption spectra of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1 in different solvents;

[0042] Figure 9 This is a graph showing the lower limit of detection of the lily of the valley aldehyde internal rotation functional molecule prepared in Example 1;

[0043] Figure 10 These are emission spectra of the lily of the valley aldehyde-based internal rotation functional molecule prepared in Example 1 in different fluid foods. DETAILED DESCRIPTION

[0044] The present invention provides a lily of the valley aldehyde-based internal rotation functional molecule, named 2,6-bis((3-4-(tert-butyl)phenyl)-2-methylpropylene)amino-4-(piperidin-1-yl)pyrimidine-1-oxide;

[0045] Its structural formula is shown below:

[0046]

[0047] In the present invention, 2,6-bis((3-4-(tert-butyl)phenyl)-2-methylpropylidene)amino-4-(piperidin-1-yl)pyrimidine-1-oxide is referred to as BPMPPO, and its molecular formula is C 37 H 51 N5O, the theoretical relative molecular mass is 581.84.

[0048] The present invention provides a method for preparing a lily of the valley aldehyde-based internal rotation functional molecule, comprising the following steps:

[0049] Step 1), mixing lily of the valley aldehyde and solvent 1 to obtain a lily of the valley aldehyde solution; mixing an organic base and solvent 2 to obtain an organic base solution; mixing minoxidil and solvent 3 to obtain a minoxidil solution;

[0050] Step 2), mixing the lilysinaldehyde solution and the organic base solution to obtain a mixed solution, adding the minoxidil solution, and then performing a conjugated coupling reaction to obtain a reaction solution containing a lilysinaldehyde internal rotation functional molecule;

[0051] Step 3) extracting, purifying, recrystallizing and drying the reaction solution containing the lily of the valley aldehyde internal rotation functional molecule in sequence to obtain the lily of the valley aldehyde internal rotation functional molecule.

[0052] In the present invention, in step 1), the concentration of the lilysulphide solution is 2 to 4 mol / L, preferably 3 mol / L; the concentration of the organic base solution is 1 to 8 mol / L, preferably 2 to 6 mol / L, more preferably 3 mol / L; the concentration of the minoxidil solution is 1 to 3 mol / L, preferably 2 mol / L.

[0053] In the present invention, in step 1), the organic base includes one or more of triethylamine, trimethylamine, N,N-diisopropylethylamine, pyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine, lithium diisopropylamide, sodium bis(trimethylsilyl)amide, sodium tert-butoxide, potassium tert-butoxide and N,N,N',N'-tetramethylethylenediamine, preferably one or more of triethylamine, trimethylamine, N,N-diisopropylethylamine, pyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine, lithium diisopropylamide, sodium bis(trimethylsilyl)amide and sodium tert-butoxide, further preferably one or more of triethylamine, trimethylamine, N,N-diisopropylethylamine and pyridine;

[0054] The solvent 1 includes one or more of methanol, acetonitrile, tetrahydrofuran, ethanol, N,N-dimethylformamide, ethyl acetate and dimethyl sulfoxide, preferably one or more of methanol, acetonitrile, tetrahydrofuran, ethanol and N,N-dimethylformamide, more preferably one or more of methanol, acetonitrile and tetrahydrofuran;

[0055] The second solvent and the third solvent independently include one or more of methanol, ethanol, propylene glycol, ethylene glycol, isopropanol, n-butanol and cyclohexanol, preferably independently include one or more of methanol, ethanol, propylene glycol, ethylene glycol and isopropanol, and further preferably independently include one or more of methanol, ethanol and propylene glycol.

[0056] In the present invention, in step 1), when the lilysulphide and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., preferably 30 to 40° C., more preferably 35° C.; the stirring speed is 100 to 900 rpm, preferably 200 to 800 rpm, more preferably 500 rpm; the stirring time is 0.1 to 1 h, preferably 0.2 to 0.8 h, more preferably 0.5 h;

[0057] When the organic base and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., preferably 30 to 40° C., more preferably 35° C.; the stirring speed is 100 to 900 rpm, preferably 200 to 800 rpm, more preferably 500 rpm; the stirring time is 0.1 to 1 h, preferably 0.2 to 0.8 h, more preferably 0.5 h;

[0058] When the minoxidil and solvent 2 are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., preferably 30 to 40° C., and more preferably 35° C.; the stirring speed is 100 to 900 rpm, preferably 200 to 800 rpm, and more preferably 500 rpm; the stirring time is 0.1 to 1 h, preferably 0.2 to 0.8 h, and more preferably 0.5 h.

[0059] In the present invention, the molar ratio of minoxidil to organic base is 1:2-8, preferably 1:4-6; more preferably 1:5;

[0060] The molar ratio of minoxidil to lilyral is 1:2-4, preferably 1:3.

[0061] In the present invention, in step 2), the mixing temperature is 23 to 34° C., preferably 25° C.; the mixing time is 0.5 to 2 h, preferably 1 to 1.6 h, and more preferably 1.3 h;

[0062] The mixing is carried out under stirring conditions, and the stirring rate is 900-1800 rpm, preferably 1200-1500 rpm, and more preferably 1400 rpm;

[0063] The minoxidil solution is added under heating conditions, and the heating rate is 1-5°C / min, preferably 3°C / min; the minoxidil solution is added at a rate of 5-20 mL / min, preferably 8-15 mL / min, and more preferably 12 mL / min;

[0064] The conjugated coupling reaction temperature is 70-110° C., preferably 90° C.; the time is 1-24 h, preferably 3-20 h, more preferably 5-15 h, and more preferably 10 h.

[0065] In the present invention, in step 3), the reaction solution containing the lily of the valley aldehyde internal rotation functional molecule is preferably extracted after removing the solvent at a pressure of -0.09 MPa to -0.07 MPa;

[0066] In the present invention, the extraction solvent is preferably a mixed solution of ethyl acetate and purified water, and the volume ratio of ethyl acetate to purified water is 1 to 10:1, preferably 3 to 7:1, and more preferably 5:1; after extraction, the solvent is removed by vacuum filtration to obtain a crude product, and the pressure of the vacuum filtration is preferably -0.09 MPa to -0.07 MPa.

[0067] In the present invention, in step 3), the purification is to dissolve the crude product in a mixed solution and purify it by silica gel powder. The mixed solution is preferably a mixed solution of dichloromethane and methanol, and the volume ratio of dichloromethane to methanol is 10 to 30:1, more preferably 20:1; the silica gel powder is preferably chromatographic grade silica gel powder, and the particle size is preferably 300 to 600 mesh.

[0068] In the present invention, in step 3), the purified product is redispersed in a mixed solution of ethanol and purified water for recrystallization to precipitate crystalline powder to obtain a crystalline product;

[0069] The volume ratio of the ethanol to purified water is 1:2-15, preferably 1:5-10;

[0070] The solid content of the mixed solution is 1 to 100 mg / mL, preferably 20 to 80 mg / mL, and more preferably 50 mg / mL;

[0071] The recrystallization temperature is 1 to 10°C, more preferably 3 to 7°C.

[0072] In the present invention, in step 3), the drying is freeze-drying, the freeze-drying temperature is -50 to -5°C, more preferably -40 to -10°C, more preferably -30°C; the freeze-drying time is 12 to 28 hours, more preferably 15 to 24 hours, more preferably 20 hours.

[0073] The present invention also provides an application of a lily of the valley aldehyde-based internal rotation functional molecule in detecting the degree of gelation of food. The lily of the valley aldehyde-based internal rotation functional molecule, a solvent, and a test sample are mixed to obtain a mixed solution. The intensity of the light signal released by the mixed solution at 420-750 nm is detected, and the degree of gelation of the food sample to be tested is calculated based on a standard curve of the light signal intensity and viscosity.

[0074] In the present invention, the degree of gelation of the food is characterized by physical micro-domain viscosity.

[0075] In the present invention, the usage ratio of the lilysinaldehyde internal rotation functional molecule, the solvent and the test sample is 1-100 μmol:1L:0.005L, preferably 20-80 μmol:1L:0.005L, and more preferably 50 μmol:1L:0.005L;

[0076] In the present invention, the solvent comprises one or more of ethyl acetate, fructose and triacetin, preferably ethyl acetate and / or fructose;

[0077] The sample to be tested preferably includes one or more of glycerol, food gel, food jelly, fluid food and liquid food.

[0078] In the present invention, the detection is performed in a fluorescence detection device, and the excitation wavelength of the fluorescence detection device is 330 nm.

[0079] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0080] Example 1

[0081] Add 612.93 g (3 mol) of lilysaldehyde to tetrahydrofuran, and stir at 400 rpm at 35°C for 0.5 h to obtain a 3 M lilysaldehyde solution;

[0082] Dissolve 505.95 g (5 mol) of triethylamine organic base in ethanol and stir at 400 rpm at 35°C for 1.0 h to obtain a 5 M triethylamine organic base solution;

[0083] Add 209.25 g (1 mol) of minoxidil to methanol and stir at 400 rpm at 35°C for 1 h to obtain a 2 M minoxidil solution.

[0084] First, the lily of the valley aldehyde solution and the organic base solution were directly mixed at room temperature (25°C), the stirring rate was controlled to 1500 rpm, and the stirring time was 1.0 h. Then, the stirring rate was kept constant, and the minoxidil solution was added to the above-mentioned mixed solution at an addition rate of 10 mL / min during the heating process. The heating rate was 2°C / min until it rose to the target temperature of 90°C for conjugated coupling reaction. After 12 hours of reaction, a reaction solution containing a lily of the valley aldehyde internal rotation functional molecule was obtained.

[0085] After the reaction is completed, the reaction solution containing the lily of the valley aldehyde internal rotation functional molecule is sequentially extracted, purified, recrystallized and dried. The specific operation steps are as follows:

[0086] The reaction solution containing the lilysinaldehyde internal rotation functional molecule was subjected to solvent removal at -0.08 MPa, and then extracted with a mixed solution of ethyl acetate and purified water in a volume ratio of 5:1. The organic phase was collected and then decompressed to -0.08 MPa to remove the solvent to obtain a crude product. The crude product was dissolved in a mixed solution of dichloromethane and methanol, with the volume ratio of dichloromethane to methanol controlled at 20:1, and purified using chromatographic grade silica gel powder (500 mesh). The purified product was redispersed in a mixed solution of ethanol and purified water, with the solid content of the solution controlled at 50 mg. / mL, the volume ratio of ethanol and purified water is 1:8, and it is placed at a low temperature of 5°C for 6 hours to precipitate crystalline powder, and the crystalline powder is filtered using rapid filter paper, and the reduced pressure is controlled to be -0.08 MPa. During the filtration process, it is repeatedly rinsed with a mixed solution of ethanol and purified water, and the volume ratio of ethanol and purified water is controlled to be 1:10, and this is repeated twice; the filtered product is placed in a freeze drying oven and dried at -25°C for 20 hours to obtain a lily of the valley aldehyde-based internal rotation functional molecule, recorded as BPMPPO, with a yield of 536.46 g and a yield of 92.2%.

[0087] The relative molecular mass of the lily of the valley aldehyde internal rotation functional molecule BPMPPO obtained in Example 1 was analyzed by mass spectrometry. The results are as follows: Figure 2 As shown. Figure 2 It can be seen that the relative molecular mass of the lily of the valley aldehyde internal rotation functional molecule BPMPPO is 581.84914 [M] + , the molecular formula of formula 1 is C 37 H 51 The theoretical relative mass of N5O is estimated to be 581.84900. In terms of relative molecular mass, it can be found that the product obtained in Example 1 is consistent with the target product.

[0088] At the same time, the chemical structure of the obtained product was tested, and the nuclear magnetic resonance carbon spectrum was Figure 3 As shown. Figure 3 It can be seen that 13C NMR (101 MHz, DMSO-d6) δ163.71, 151.88, 150.45, 135.11, 128.42, 126.78, 121.81, 48.30, 43.90, 42.11, 33.92, 31.22, 24.51, 22.45, 16.89. The carbon skeleton displacement in its molecular structure was confirmed, and it was determined to be the target product, lily of the valley aldehyde-based internal rotation functional molecule BPMPPO.

[0089] Example 2

[0090] 408.62 g (2 mol) of lilysaldehyde was added to tetrahydrofuran, and the mixture was stirred at 500 rpm at 25°C for 1.0 h to obtain a 2 M lilysaldehyde solution;

[0091] Dissolve 202.4 g (2 mol) of triethylamine in ethanol and stir the mixture at 500 rpm at 25°C for 2 h to obtain a 2 M triethylamine solution.

[0092] Add 209.25 g (1 mol) of minoxidil to methanol and stir at 500 rpm at 25°C for 1.5 h to obtain a minoxidil solution with a concentration of 1 M.

[0093] First, the lily of the valley aldehyde solution and the organic base solution were directly mixed at room temperature (25°C), the stirring rate was controlled to 900 rpm, and the stirring time was 2.0 h. Then, the stirring rate was kept constant, and the minoxidil solution was added to the above-mentioned mixed solution at an addition rate of 5 mL / min during the heating process. The heating rate was 1°C / min until it reached the target temperature of 70°C for conjugated coupling reaction. After 24 hours of reaction, a reaction solution containing lily of the valley aldehyde internal rotation functional molecules was obtained.

[0094] The obtained reaction solution containing the lily of the valley aldehyde internal rotation functional molecule is sequentially subjected to extraction, purification, crystallization, centrifugation and drying. The specific operation steps are as follows:

[0095] The reaction solution containing the lily of the valley aldehyde internal rotation functional molecule was subjected to solvent removal at -0.09 MPa, and then extracted with a mixed solution of ethyl acetate and purified water in a volume ratio of 1:1. The organic phase was collected and then decompressed to -0.09 MPa to remove the solvent to obtain a crude product. The crude product was dissolved in a mixed solution of dichloromethane and methanol, with the volume ratio of dichloromethane to methanol being controlled to be 10:1, and purified using chromatographic grade silica gel powder (300 mesh). The purified product was redispersed in a mixed solution of ethanol and purified water, with the solid content of the solution being controlled to be 1m g / mL, the volume ratio of ethanol and purified water is 1:2, and it is placed at a low temperature of 1°C for 1 hour to precipitate crystalline powder. The crystalline powder is filtered using rapid filter paper, and the reduced pressure is controlled at -0.09 MPa. During the filtration process, it is repeatedly rinsed with a mixed solution of ethanol and purified water, and the volume ratio of ethanol and purified water is controlled at 1:5, and repeated 4 times; the filtered product is placed in a freeze drying oven and dried at -5°C for 28 hours to obtain a lily of the valley aldehyde-based internal rotation functional molecule, recorded as BPMPPO, with a yield of 502.13 g and a yield of 86.3%.

[0096] The high-resolution mass spectrometry results and nuclear magnetic resonance spectrum of the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO prepared in this example are consistent with the results obtained in Example 1.

[0097] Example 3

[0098] 817.24 g (4 mol) of lilysaldehyde was added to tetrahydrofuran, and the mixture was stirred at 300 rpm at 50° C. for 0.1 h to obtain a 4 M lilysaldehyde solution;

[0099] Dissolve 809.6 g (8 mol) of triethylamine organic base in ethanol and stir at 300 rpm at 50°C for 0.1 h to obtain an 8 M triethylamine organic base solution;

[0100] Add 209.25 g (1 mol) of minoxidil to methanol and stir at 300 rpm at 50°C for 0.1 h to obtain a 3 M minoxidil solution;

[0101] First, the lily of the valley aldehyde solution and the organic base solution were directly mixed at room temperature (25°C), the stirring rate was controlled to 1800 rpm, and the stirring time was 0.5 h. Then, the stirring rate was kept constant, and the minoxidil solution was added to the above-mentioned mixed solution at an addition rate of 20 mL / min during the heating process. The heating rate was 5°C / min until it rose to the target temperature of 110°C for conjugated coupling reaction. After the reaction for 1 h, a reaction solution containing a lily of the valley aldehyde internal rotation functional molecule was obtained.

[0102] The obtained reaction solution containing the lily of the valley aldehyde internal rotation functional molecule is sequentially subjected to extraction, purification, crystallization, centrifugation and drying. The specific operation steps are as follows:

[0103] The reaction solution containing the lilysinaldehyde internal rotation functional molecule was subjected to solvent removal at -0.07 MPa, and then extracted with a mixed solution of ethyl acetate and purified water in a volume ratio of 10:1. The organic phase was collected and then decompressed to -0.07 MPa to remove the solvent to obtain a crude product. The crude product was dissolved in a mixed solution of dichloromethane and methanol, with the volume ratio of dichloromethane to methanol controlled at 30:1, and purified using chromatographic grade silica gel powder (600 mesh). The purified product was redispersed in a mixed solution of ethanol and purified water, with the solid content of the solution controlled at 100 mg. / mL, the volume ratio of ethanol to purified water is 1:15, and it is placed at a low temperature of 10°C for 12 hours to precipitate crystalline powder, and the crystalline powder is filtered using rapid filter paper, and the reduced pressure is controlled to be -0.07 MPa. During the filtration process, it is repeatedly rinsed with a mixed solution of ethanol and purified water, and the volume ratio of ethanol to purified water is controlled to be 1:20, and this is repeated once; the filtered product is placed in a freeze drying oven and dried at -50°C for 12 hours to obtain a lily of the valley aldehyde-based internal rotation functional molecule, recorded as BPMPPO, with a yield of 489.91 g and a yield of 84.2%.

[0104] The high-resolution mass spectrometry results and nuclear magnetic resonance spectrum of the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO prepared in this example are consistent with the results obtained in Example 1.

[0105] Performance Testing

[0106] The lily of the valley aldehyde-based internal rotation functional molecule obtained in Example 1 was subjected to various spectroscopic tests.

[0107] 1) Viscosity sensitivity test

[0108] By mixing different proportions of glycerol and purified water to obtain solutions of different viscosities (1.0 cP to 956.0 cP), BPMPPO, a functional molecule of lily of the valley aldehyde, was added to each solution at a concentration of 10 μM. The excitation wavelength was controlled at 330 nm and the test was performed at room temperature. (The corresponding relationship between the viscosity of the solution and the glycerol content in the solution is shown in Table 1. The spectrum obtained by the test is shown in Figure 4 shown.

[0109] Table 1 Correspondence between solution viscosity and glycerol content

[0110] Viscosity (cP) 1.00 1.74 3.72 10.72 58.89 956.00 Glycerol volume percentage (%) 0 10 30 50 70 99

[0111] Combined with Table 1, Figure 4It can be seen that as the solution viscosity increases from 1.0 cP to 956.0 cP, the observable light signal intensity gradually increases, especially when the glycerol addition amount exceeds 50%, the released light signal intensity increases sharply. When in glycerol, the light signal intensity reaches its maximum value, which is about 80 times higher than the solution system with a glycerol volume fraction of 0% (purified water system).

[0112] In addition, the relationship between the optical signal intensity and the viscosity of the fluid micro-area was established, where the solution viscosity ranged from 1.00 to 956.00 cP. The optical signal intensity and the viscosity of the fluid micro-area were converted into logarithmic functions and fitted into a straight line, which was consistent with the results. Relational, Figure 5 is a linear fitting diagram between the light signal intensity and the solution viscosity, and Table 2 is the specific logarithmic function value.

[0113] Table 2 Correspondence between the logarithm of solution viscosity and the logarithm of fluorescence intensity

[0114]

[0115] Combine Figure 5 As shown in Table 2, the viscosity sensitivity coefficient of BPMPPO is 0.68, and the fitted coefficient of determination is 0.98, indicating that this internal rotation molecular tool exhibits high sensitivity to fluid micro-region viscosity. These results demonstrate that the lysinaldehyde-based internal rotation functional molecule BPMPPO provided by this invention can be used as a molecular tool to measure the degree of food gelation. The strength of the apparent light signal can be used to determine the degree of food gelation, providing data support and solutions for rapid, efficient, and visual modulation process optimization.

[0116] 2) pH stability test

[0117] 1.12 mg of the lily of the valley aldehyde internal rotation functional molecule BPMPPO prepared in Example 1 was dissolved in ethyl acetate, wherein the BPMPPO concentration was 2 mM. The BPMPPO was added to a buffer solution with a pH of 3.0 to 11.0 to make the BPMPPO concentration 10 μM. The change in the optical signal intensity was tested at room temperature. The test results are as follows: Figure 6 shown.

[0118] Depend on Figure 6 It can be seen that the fluorescence intensity of the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO shows a weak fluorescence signal release intensity in the pH range of 3.0 to 11.0, showing good light signal release stability, indicating that the internal rotation functional molecule has good pH tolerance and is not easily disturbed by pH.

[0119] 3) Light stability test

[0120] 1.75 mg of the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO prepared in Example 1 was dissolved in ethyl acetate to a BPMPPO concentration of 3 mM. The solution was then added to low-viscosity purified water (1.0 cP) and a high-viscosity 90% volume fraction glycerol solution (956.0 cP) to a BPMPPO concentration of 10 μM. The light signal intensity was tested for changes within 60 minutes under continuous irradiation with an external excitation light source at 330 nm. The test results are shown in FIG. Figure 7 The obtained data are shown in Table 3.

[0121] Table 3 Variation of optical signal intensity of BPMPPO obtained in Example 1 in purified water and glycerol

[0122] Time / min 0 10 20 30 60 Fluorescence intensity in purified water / au 45.1 44.6 44.3 44.1 43.8 Fluorescence intensity in glycerol / au 4056.2 4051.3 4048.2 4045.2 4036.4

[0123] Combined with Table 3 and Figure 7 It can be seen that the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO obtained in Example 1 can maintain good light stability in both high-viscosity glycerol and low-viscosity purified water, and still has good durability even under long-term irradiation.

[0124] 4) Polarity tolerance test

[0125] 2.33 mg of the lily of the valley aldehyde internal rotation functional molecule BPMPPO prepared in Example 1 was dissolved in ethyl acetate, wherein the concentration of BPMPPO was 4 mM, and the BPMPPO was added to a variety of conventional solvents of different polarities to make the concentration of BPMPPO 10 μM. The absorbance signal pattern under different polar solvent atmospheres was tested. The above test was carried out at room temperature. The results are as follows: Figure 8 shown.

[0126] Depend on Figure 8 The results show that in a variety of solvents (including dichloromethane, toluene, dimethyl sulfoxide, methanol, acetonitrile, and tetrahydrofuran), the absorbance of the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO is around 0.44, and the peak of its absorption spectrum is around 330nm. The overall results indicate that the molecular tool BPMPPO is insensitive to the polarity of the solvent and is suitable for use in food gels containing multiple polar components.

[0127] 5) Detection limit of BPMPPO

[0128] 2.91 mg of the lilysin-based internal rotation functional molecule BPMPPO prepared in Example 1 was dissolved in linoleic acid, and the concentration of BPMPPO was controlled to be 5 mmol / L. During the test, the concentration was diluted to 10 μmol / L, and the mixture was added to a mixed solution of water and glycerol with extremely low viscosity to test its detection sensitivity to the viscosity of the fluid micro-area. The above test was carried out at room temperature. Figure 9 The linear fitting diagram of the detection limit of BPMPPO obtained in Example 1 (I 513 Refers to the I value corresponding to the wavelength of 513nm). Figure 9 It can be seen that in food fluids with low gelation degree, the viscosity value of BPMPPO and the logarithm of the light signal release intensity have a good linear relationship (y=0.79x+1.70), and the fitting coefficient of determination is 0.99. Through this linear relationship, the detection limit of BPMPPO is 1.05cP, indicating that it is very sensitive to changes in micro-area viscosity and is suitable for regulating and monitoring changes in the viscosity of vegetable oils.

[0129] Application Example 1

[0130] 3.49 mg of the lily of the valley aldehyde internal rotation functional molecule BPMPPO prepared in Example 1 was dissolved in ethanol to obtain a BPMPPO solution with a concentration of 6 mmol / L, and then added to food pectin 1, food pectin 2 and food pectin 3, respectively, so that the concentration of BPMPPO was 10 μmol / L; then, the emission spectra of the three different food pectins added with BPMPPO were tested at room temperature, and the external excitation light source was 330 nm. The obtained emission spectra are shown in the figure below. Figure 10 The optical signal intensity and viscosity of different mixed solutions are shown in Table 4.

[0131] Table 4 Optical signal intensity and viscosity of pectin from different foods

[0132] Sample Optical signal strength Viscosity Food Pectin 1 1287.6 104.8cP Food Pectin 2 2817.6 323.8cP Food Pectin 3 4998.3 911.4cP

[0133] Combine Figure 10 As can be seen from the data obtained in Table 4, there are large differences in the degree of gelation of the three types of food pectins, which in turn leads to a certain degree of differentiation in the intensity of the light signal. Specifically, the light signal intensity of food pectin 1 is the lowest, indicating that its food gelation degree is low. The test data show that its micro-area viscosity is 104.8cP; the light signal of food pectin 2 is enhanced to a certain extent, indicating that its gelation is high, and the micro-area viscosity has increased to a certain extent. The test data show that its viscosity is 323.8cP; the light signal intensity of food pectin 3 further increases, indicating that the overall gelation degree further increases. The test data show that its micro-area viscosity is 911.4cP. It can be seen that the lily of the valley aldehyde-based internal rotation functional molecule BPMPPO provided by the present invention can present light signal intensities of different intensities to fluid foods of different gelation, and its release wavelength peak is 513nm, which is bright green light, with significant visualization effect, and has a significant advantage in in-situ measurement.

[0134] As can be seen from the above embodiments, the present invention provides a lily of the valley aldehyde-based internal rotation functional molecule and its preparation method and application. The lily of the valley aldehyde described in the present invention is obtained by further conjugating and coupling a post-synthetic lily of the valley extract with another post-synthetic natural extract, minoxidil. The preparation process is achieved by a one-step method to obtain a lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO). The lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO) provided by the present invention has an internal rotation structure of conjugated single and double bonds, and can exhibit different rotation states in fluid atmospheres with different micro-area viscosities, which are then converted into light signals and released to achieve rapid, efficient, and visual detection of the degree of gelation of food. It is particularly suitable for detecting the degree of gelation of fluid foods containing a large amount of pseudoplastic components. It can be more intuitively presented in situ through the strength of the apparent light signal, and the measurement can be completed without a mechanical shearing process. Various test results show that the lily of the valley aldehyde-based internal rotation functional molecule (BPMPPO) has a high micro-area viscosity sensitivity coefficient (x = 0.68), good pH tolerance and excellent light stability. Furthermore, this BPMPPO-based endo-rotation functionalized molecule exhibits strong tolerance to solvents of varying polarity, making it suitable for real-time viscosity measurement of micro-regions in fluidized foods. It also exhibits a low detection limit (as low as 1.05 cP). Furthermore, the preparation of this BPMPPO-based endo-rotation functionalized molecule is simple and environmentally friendly, with milligram-level usage. Both preparation and usage costs are very low, making it suitable for large-scale industrial production and widespread application.

[0135] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A lily of the valley aldehyde internal rotation functional molecule, characterized in that Designated as 2,6-bis((3-4-(tert-butyl)phenyl)-2-methylpropylidene)amino-4-(piperidin-1-yl)pyrimidine-1-oxide; Its structural formula is shown below:

2. The method for preparing a lilysinaldehyde-based internal rotation functional molecule according to claim 1, characterized in that: The following steps are involved: Step 1), mixing lily of the valley aldehyde and solvent 1 to obtain a lily of the valley aldehyde solution; mixing an organic base and solvent 2 to obtain an organic base solution; mixing minoxidil and solvent 3 to obtain a minoxidil solution; Step 2), mixing the lilysinaldehyde solution and the organic base solution to obtain a mixed solution, adding the minoxidil solution, and then performing a conjugated coupling reaction to obtain a reaction solution containing a lilysinaldehyde internal rotation functional molecule; Step 3) extracting, purifying, recrystallizing and drying the reaction solution containing the lily of the valley aldehyde internal rotation functional molecule in sequence to obtain the lily of the valley aldehyde internal rotation functional molecule.

3. The method for preparing a lilysinaldehyde-based internal rotation functional molecule according to claim 2, wherein: In step 1), the concentration of the lilysaldehyde solution is 2-4 mol / L, the concentration of the organic base solution is 1-8 mol / L, and the concentration of the minoxidil solution is 1-3 mol / L.

4. The method for preparing a lilysinal-based internal rotation functional molecule according to claim 2 or 3, characterized in that: In step 1), the organic base includes one or more of triethylamine, trimethylamine, N,N-diisopropylethylamine, pyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine, lithium diisopropylamide, sodium bis(trimethylsilyl)amide, sodium tert-butoxide, potassium tert-butoxide and N,N,N',N'-tetramethylethylenediamine; The solvent 1 includes one or more of methanol, acetonitrile, tetrahydrofuran, ethanol, N,N-dimethylformamide, ethyl acetate and dimethyl sulfoxide; The second solvent and the third solvent independently include one or more of methanol, ethanol, propylene glycol, ethylene glycol, isopropanol, n-butanol and cyclohexanol.

5. The method for preparing a lilysinal-based internal rotation functional molecule according to claim 4, characterized in that: In step 1), when the lilysulphide and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 h; When the organic base and the solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 h; When the minoxidil and the second solvent are mixed, the mixing is carried out under stirring conditions, the stirring temperature is 25 to 50° C., the stirring speed is 100 to 900 rpm, and the stirring time is 0.1 to 1 hour.

6. The method for preparing a lilysinal-based internal rotation functional molecule according to claim 2 or 5, characterized in that: The molar ratio of minoxidil to organic base is 1:2-8; The molar ratio of minoxidil to lilyral is 1:2-4.

7. The method for preparing a lilysinal-based internal rotation functional molecule according to claim 6, characterized in that: In step 2), the mixing temperature is 23 to 34° C., and the mixing time is 0.5 to 2 h; The mixing is carried out under stirring conditions at a rate of 900 to 1800 rpm; The minoxidil solution is added under heating conditions, the heating rate is 1 to 5°C / min, and the minoxidil solution is added at a rate of 5 to 20 mL / min; The temperature of the conjugation coupling reaction is 70-110° C., and the time is 1-24 hours.

8. The use of the lilysinal-based internal rotation functional molecule according to claim 1 in detecting the degree of gelation of food, characterized in that: The lily of the valley aldehyde internal rotation functional molecule, solvent and test sample are mixed to obtain a mixed solution. The intensity of the light signal released by the mixed solution at 420-750 nm is detected, and the degree of gelation of the food sample to be tested is calculated based on a standard curve of light signal intensity and viscosity.

9. The use of the lilysinal-based internal rotation functional molecule in the detection of food gelation degree according to claim 8, characterized in that: The usage ratio of the lily of the valley aldehyde internal rotation functional molecule, the solvent and the test sample is 1-100 μmol:1L:0.005L.

10. The use of the lilysulphide-based internal rotation functional molecule according to claim 8 or 9 in the detection of the degree of gelation of food, characterized in that: The solvent includes one or more of ethyl acetate, fructose and triacetin; The sample to be tested includes one or more of glycerol, food gel, food jelly, fluid food and liquid food.

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