Preparation method and application of compound

Abstract

The present invention relates to the field of pigments, and discloses a compound preparation method, which is characterized by comprising: mixing a compound represented by a formula 1 and a compound represented by a formula 2, and carrying out a chemical reaction, wherein the concentration of the compound as shown in the formula 1 in a reaction system is 0.1-5mM; the temperature of the chemical reaction is 35-80 DEG C; the chemical reaction is carried out under the condition that the pH (Potential of Hydrogen) is 1.5 to 3.5. According to the method, specific synthesis conditions of catechol-based pyran dimethyl delphinidin-3-O-glucoside are provided, the specific synthesis conditions comprise the concentration of the raw material dimethyl delphinidin-3-O-glucoside in a reaction system, the reaction temperature, the reaction pH value and the like, the conversion rate of the raw material dimethyl delphinidin-3-O-glucoside can be increased to 26.11%, and the yield of the catechol-based pyran dimethyl delphinidin-3-O-glucoside can be increased to 26.11%. And the time for the reaction to reach the maximum conversion rate is shortened as much as possible. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the field of pigments, and particularly to a preparation method and application of a compound. Background Art

[0002] Anthocyanin is one of the most important pigments in nature. It belongs to flavonoid compounds and has a typical C6-C3-C6 backbone structure. Its basic structure is 3,5,7-trihydroxy-2-phenylbenzopyran, which is widely present in the leaves, stems, roots, flowers and fruits of plants and has significant biological activities. The basic structure of anthocyanin is Figure 1 the oxonium ion shown in. According to different substituents, the anthocyanidin types can be divided into 6 kinds, namely pelargonidin, cyanidin, delphinidin, peonidin, petunidin and malvidin. Pyranoanthocyanins are the main polyphenolic pigments formed during the aging and maturation of red wine. They are formed by the direct reaction of free anthocyanins with some yeast by-products, such as acetaldehyde, pyruvic acid, acetoacetic acid, vinyl phenol, etc. at the 4th and 5th positions of anthocyanins, and further cyclized to form another type of stable pigment. Generally speaking, pyranoanthocyanins are the most important class of anthocyanin-derived pigments naturally present in red wine. Pyranoanthocyanins are more stable than anthocyanins and exhibit different colors. However, so far, the reports on catechol-based pyrano malvidin-3-O-glucoside mostly focus on the identification of anthocyanins, and do not involve the specific synthesis conditions and conversion rates of catechol-based pyrano malvidin-3-O-glucoside. Therefore, a method for catechol-based pyrano malvidin-3-O-glucoside is needed to improve the conversion rate and save time. Summary of the Invention

[0003] The purpose of the present invention is to overcome the problem in the prior art that the specific synthesis conditions and conversion rates of catechol-based pyrano malvidin-3-O-glucoside are lacking, and to provide a preparation method and application of a compound.

[0004] To achieve the above purpose, the first aspect of the present invention provides a preparation method of a compound, which is characterized in that the method includes: mixing the compound shown in Formula 1 and the compound shown in Formula 2 and carrying out a chemical reaction;

[0005]

[0006] Among them, the two R1 in Formula 1 can be the same or different and are each independently selected from H, hydroxyl, C1-C4 alkyl or C1-C4 alkoxy; the seven R2 in Formulas 1 and 2 can be the same or different and are each independently selected from H or C1-C4 alkyl; R3 is selected from substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted heterocyclic group;

[0007] Among them, the concentration of the compound shown in Formula 1 in the reaction system is 0.1-5 mM; the temperature of the chemical reaction is 45-80 °C; the chemical reaction is carried out under the condition of pH 1.5-3.5.

[0008] The second aspect of the present invention provides the application of the method described in the first aspect of the present invention in improving the conversion rate of the compound shown in Formula 1 and shortening the time required to reach the conversion rate.

[0009] Through the above technical solutions, the preparation method of the compound of the present invention provides specific synthesis conditions for catechol-based pyranocyanidin-3-O-glucoside, including the concentration of the raw material cyanidin-3-O-glucoside in the reaction system, the reaction temperature, and the pH value of the reaction, etc., which can increase the conversion rate of the raw material cyanidin-3-O-glucoside to 26.11%, and shorten the time for the reaction to reach the maximum conversion rate as much as possible (which can reach about 16 days). Description of the Drawings

[0010] Figure 1 is the high-resolution mass spectrum of catechol-based pyranocyanidin-3-O-glucoside;

[0011] Figure 2 is the trend chart of the peak area of catechol-based pyranocyanidin-3-O-glucoside changing with time in each example and comparative example (wherein, black represents the concentration of the substrate cyanidin-3-O-glucoside fitted by the second-order polynomial, and red represents the concentration of the product catechol-based pyranocyanidin-3-O-glucoside fitted by the second-order polynomial). Detailed Embodiments

[0012] In the ranges disclosed herein, the endpoints and any values are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0013] As described above, the first aspect of the present invention provides a method for preparing a compound, characterized in that the method includes: mixing the compound shown in Formula 1 and the compound shown in Formula 2 and carrying out a chemical reaction;

[0014]

[0015] Among them, the two R1 in Formula 1 can be the same or different and are each independently selected from H, hydroxyl, C1-C4 alkyl, or C1-C4 alkoxy; the total of 7 R2 in Formula 1 and Formula 2 can be the same or different and are each independently selected from H or C1-C4 alkyl; R3 is selected from substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted heterocyclic group;

[0016] Among them, the concentration of the compound shown in Formula 1 in the reaction system is 0.1-5 mM (such as 0.1 mM, 0.4 mM, 0.6 mM, 0.8 mM, 1 mM, 1.2 mM, 1.5 mM, 2 mM, 3 mM, 4 mM, 5 mM, or any value between the above values); the temperature of the chemical reaction is 45-80 °C (such as 45 °C, 48 °C, 50 °C, 52 °C, 55 °C, 60 °C, 70 °C, 80 °C, or any value between the above values); the chemical reaction is carried out under the condition of pH 1.5-3.5 (such as 1.5, 2, 2.5, 3, 3.2, 3.5, or any value between the above values).

[0017] In some embodiments of the present invention, preferably, R1 is selected from H, hydroxyl, methyl, ethyl, methoxy.

[0018] In some embodiments of the present invention, preferably, R2 is selected from H, methyl, or ethyl.

[0019] In some embodiments of the present invention, preferably, R3 is selected from substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted glycosyl.

[0020] In some embodiments of the present invention, preferably, the concentration of the compound shown in Formula 1 in the mixed system formed by the auxiliary agent, the compound shown in Formula 1, and the compound shown in Formula 2 is 0.5-3 mM.

[0021] In some embodiments of the present invention, preferably, the temperature of the chemical reaction is 45-70 °C.

[0022] In some embodiments of the present invention, preferably, the chemical reaction is carried out under the condition of pH 2.5-3.5.

[0023] In some embodiments of the present invention, preferably, R1 is selected from H, hydroxyl, or methoxy.

[0024] In some embodiments of the present invention, preferably, R2 is selected from H or methyl.

[0025] In some embodiments of the present invention, preferably, R3 is selected from substituted or unsubstituted glycosyl.

[0026] In some embodiments of the present invention, preferably, the concentration of the compound represented by Formula 1 in the mixed system formed by the auxiliary agent, the compound represented by Formula 1 and the compound represented by Formula 2 is 1 - 2 mM.

[0027] In some embodiments of the present invention, preferably, the temperature of the chemical reaction is 45 - 55 °C.

[0028] In some embodiments of the present invention, preferably, R3 is selected from pyranosyl or furanosyl, preferably glucosyl, galactosyl, mannosyl, arabinosyl, xylosyl, ribosyl or fructosyl.

[0029] In some embodiments of the present invention, preferably, R1 is methoxy, R2 is H, and R3 is glucosyl.

[0030] In some embodiments of the present invention, preferably, the chemical structure of the compound is as shown in Formula 3:

[0031]

[0032] In some embodiments of the present invention, preferably, the chemical reaction is carried out in the presence of a buffer solution.

[0033] In some embodiments of the present invention, preferably, the acid in the buffer solution is selected from at least one of phosphoric acid, citric acid and tartaric acid, more preferably tartaric acid.

[0034] In some embodiments of the present invention, preferably, the concentration of the buffer solution is 3 - 7 g / L.

[0035] In some embodiments of the present invention, preferably, the molar ratio of the compound represented by Formula 1 to the compound represented by Formula 2 is 1:1 - 4, preferably 1:2 - 3.

[0036] In some embodiments of the present invention, preferably, the mass ratio of the buffer solution to the compound represented by Formula 1 is 200 - 10000:1, preferably 400 - 2000:1.

[0037] In some embodiments of the present invention, preferably, the time of the chemical reaction is 8 - 120 days, preferably 10 - 60 days, more preferably 13 - 30 days.

[0038] In the present invention, after the chemical reaction is completed, the reaction liquid is concentrated, purified and freeze-dried to obtain the compound shown in Formula 3.

[0039] In some embodiments of the present invention, preferably, the concentration method is solid-phase extraction (SPE).

[0040] In some embodiments of the present invention, preferably, the purification method is preparative liquid phase.

[0041] In some embodiments of the present invention, preferably, the temperature of freeze-drying is -80 to -40 °C, and the time is 10 - 15 h.

[0042] The second aspect of the present invention provides the application of the method described in the first aspect of the present invention in improving the conversion rate of the compound shown in Formula 1 and shortening the time required to reach the conversion rate.

[0043] The present invention will be described in detail below through examples. In the following examples, the peak area of catechol-pyranocyanidin-3-O-glucoside was measured by a high performance liquid chromatography tandem triple quadrupole mass spectrometer; the trend of the peak area of catechol-pyranocyanidin-3-O-glucoside changing with time was obtained by fitting with a second-order polynomial; the pH value of the reaction system was measured by a pH meter method; the cyanidin-3-O-glucoside raw material was extracted from grape skins in accordance with the method reported by Zhao et al. in the literature ZHAO X, et.al.An effective method for the semi-preparative isolation ofhigh-purity anthocyanin monomers from grape pomace[J].Food Chemistry,2020,310:125830. in this laboratory, and the spectral purity reached more than 90%.

[0044] Example 1

[0045] After mixing 1 mmol of cyanidin-3-O-glucoside (the compound shown in Formula 1-1) with 5 mmol of caffeic acid (the compound shown in Formula 2-1), it was added to 1000 g of a tartaric acid buffer solution with a concentration of 5 g / L to obtain a mixed system. The concentration of cyanidin-3-O-glucoside in the mixed system was 1 mM. The mixed system was maintained at 50 °C in a constant temperature incubator for reaction. The pH value of the reaction system was maintained at about 3.0. After the reaction liquid was concentrated by solid phase extraction (SPE), it was separated by preparative liquid phase, the fractions were collected, concentrated by rotary evaporation, and freeze-dried at -60 °C for 12 h to obtain catechol-pyranocyanidin-3-O-glucoside (Formula 3). Under these conditions, the highest conversion rate of catechol-pyranocyanidin-3-O-glucoside prepared could reach 26.11%, and it took 16.5 days for the reaction to reach the maximum conversion rate. The high-resolution mass spectrum of the catechol-pyranocyanidin-3-O-glucoside is as Figure 1As shown, the main mass spectrometry peak is located at 625.1566, which basically coincides with the relative molecular mass of the compound. Each hydrogen atom (except for active hydrogens such as -OH hydrogens) in the catechol-based pyranocyanidin-3-O-glucoside molecule can find corresponding absorption peaks in its nuclear magnetic resonance hydrogen spectrum. Therefore, the above mass spectrometry and nuclear magnetic resonance spectrum data can prove that the target product catechol-based pyranocyanidin-3-O-glucoside was prepared in this example.

[0046]

[0047] 1 H NMR(400MHz,MeOD)δ7.85(s,1H,H-9),7.70(s,2H,H-2’,6’),7.67(dd,J=8.6,2.3Hz,1H,H-6”’),7.59(d,J=2.3Hz,1H,H-2”’),7.11(s,1H,H-8),6.97(d,J=8.4Hz,1H,H-5”’),6.87(d,J=2.2Hz,1H,H-6),4.85(d,J=7.7Hz,1H,H-1”),3.97(s,6H,3’,5’-OCH3),3.67-3.23(m,6H,H-2”,3”,4”,5”,6”).

[0048]

[0049] Other examples and comparative examples were all carried out according to the method of Example 1, except that at least one reaction condition among the temperature maintained in the constant temperature incubator, the concentration, and the pH value of the reaction system was changed.

[0050] The changing trend of the peak area of catechol-based pyranocyanidin-3-O-glucoside with time in each example and comparative example is as Figure 2 shown. Data such as the maximum conversion rate of the raw material cyanidin-3-O-glucoside (Compound of Formula 1) and the time required to reach the maximum conversion rate in each example and comparative example are shown in Table 1.

[0051] Table 1

[0052]

[0053]

[0054] It can be seen from the data in Table 1 that compared with the comparative examples, the examples adopting the technical solution of the present invention have significantly better effects in terms of the conversion rate of the raw material cyanidin-3-O-glucoside and shortening the time for the reaction to reach the maximum conversion rate.

[0055] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including combinations of each technical feature in any other suitable manner. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A method for preparing a compound, characterized in that, The method includes: mixing the compound shown in Formula 1 and the compound shown in Formula 2 and carrying out a chemical reaction; wherein the two R1s in Formula 1 are the same or different and each independently selected from H, hydroxyl, C1-C4 alkyl or C1-C4 alkoxy; the seven R2s in Formula 1 and Formula 2 are the same or different and each independently selected from H or C1-C4 alkyl; R3 is selected from substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted heterocyclic group; wherein the concentration of the compound shown in Formula 1 in the reaction system is 0.1-5 mM; the temperature of the chemical reaction is 45-80 °C; the chemical reaction is carried out under the condition of pH 1.5-3.

5.

2. The method according to claim 1, wherein, R1 is selected from H, hydroxyl, methyl, ethyl, methoxy; and / or, R2 is selected from H, methyl or ethyl; and / or, R3 is selected from substituted or unsubstituted C3-C10 cycloalkyl, substituted or unsubstituted glycosyl; and / or, the concentration of the compound shown in Formula 1 in the reaction system is 0.5-3 mM; and / or, the temperature of the chemical reaction is 45-70 °C; and / or, the chemical reaction is carried out under the condition of pH 2.5-3.

5.

3. The method according to claim 2, wherein, R1 is selected from H, hydroxyl or methoxy; and / or, R2 is selected from H or methyl; and / or, R3 is selected from substituted or unsubstituted glycosyl; and / or, the concentration of the compound shown in Formula 1 in the reaction system is 1-2 mM; and / or, the temperature of the chemical reaction is 45-55 °C.

4. The method according to claim 3, wherein, R3 is selected from pyranosyl or furanosyl, preferably glucosyl, galactosyl, mannosyl, arabinosyl, xylosyl, ribosyl or fructosyl.

5. The method according to claim 3 or 4, wherein R1 is methoxy, R2 is H, R3 is glucosyl.

6. The method according to claim 5, wherein The chemical structure of the compound having a pigment function is shown in Formula 3:

7. The method according to any one of claims 1-6, wherein, The chemical reaction is carried out in the presence of a buffer solution; Preferably, the acid in the buffer solution is at least one of citric acid, phosphoric acid and tartaric acid, more preferably tartaric acid; Preferably, the concentration of the buffer solution is 3-7 g / L.

8. The method according to any one of claims 1-7, wherein, The molar ratio of the compound shown in Formula 1 to the compound shown in Formula 2 is 1:1-4, preferably 1:2-3; Preferably, the mass ratio of the buffer solution to the compound shown in Formula 1 is 200-10000:1, preferably 400-2000:

1.

9. The method according to any one of claims 1-8, wherein The time of the chemical reaction is 8-120 days, preferably 10-60 days, more preferably 13-30 days.

10. Use of the method according to any one of claims 1-9 in improving the conversion rate of the compound shown in Formula 1 and shortening the time required to reach the conversion rate.

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