Preparation method of amino acid derivative containing side chain amino protection
By adding alkali to THF solution and adding Ts-Cl in batches under low temperature conditions, combined with the extraction and crystallization steps, the problems of low purity and yield of Boc-His(Ts) were solved, and efficient and environmentally friendly amino acid derivatization was achieved. Product preparation, suitable for the fields of medicine and biochemistry.
Patent Information
- Application Number
- CN202411434872.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-15
- Publication Date
- 2025-01-14
AI Technical Summary
In the prior art, the amino acid derivative Boc-His(Ts) has low purity and low yield, and there is heavy metal ion wastewater pollution during the production process, resulting in increased environmental protection pressure and high production costs.
Add alkali to THF solution to adjust pH, and add Ts-Cl in batches at low temperature. Boc-His (Ts) is prepared by extraction, concentration, recrystallization and drying steps, avoiding the use of heavy metal ions and improving the purity and yield of the product. .
It achieves high purity (over 99%) and high yields of Boc-His(Ts), which reduces operating complexity and environmental pollution, is suitable for applications in the pharmaceutical and biochemical fields, and reduces production costs.
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Figure CN119306667A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of polypeptide synthesis, and in particular to a method for preparing an amino acid derivative containing protected side chain amino groups. Background Art
[0002] In the field of peptide synthesis, the artificial synthesis process of peptides is achieved by controlling different amino acids in a specific order. In this process, protecting amino acids plays an important role as an important component of the target product. However, the main challenge faced by this process is that the functional groups of amino acids easily react with peptide synthesis reagents, resulting in an increase in by-products and a decrease in synthesis efficiency.
[0003] At present, the large-scale production technology of amino acids with protected side chain amino groups mainly utilizes the reaction of amino acids with metal ion compounds (such as copper sulfate, copper sulfide, basic copper carbonate, etc.). After dissolving it in water and heating it, a metal ion chelate of the amino acid can be formed. Then, the excess metal ion compound is removed by suction filtration, and the metal ion chelate of the amino acid is protected, and finally the metal ion chelate of the protected amino acid is obtained. Then, after rejection filtration and purification, EDTA.2Na is used for decoppering, and the target product can be obtained after multiple decoppering.
[0004] The traditional technology for producing amino acid derivatives Boc-His(Ts) seems simple on the surface, but in fact the operation process is complicated, especially when separating the metal ion chelates that protect the amino acids. This step is particularly difficult and easily introduces impurities, resulting in impure final products and low yields. In addition, the traditional process will produce a large amount of heavy metal ion wastewater, which is difficult to treat and has high production costs. In the current context of increasing environmental pressure, this is undoubtedly not conducive to the country's green production concept. Summary of the invention
[0005] In view of the above technical problems, the present application solves the problems of low purity and low yield of the amino acid derivative Boc-His (Ts) produced in the prior art, as well as the problem of reducing pollution and harm to the environment during the production process.
[0006] In order to achieve the above object, the technical solution adopted in the present application is: a method for preparing an amino acid derivative containing a side chain amino group protection, wherein the amino acid derivative is Boc-His (Ts), and the preparation method comprises the following steps:
[0007] Step 1: Dissolve Boc-His in THF solution, add alkali to adjust the pH to alkaline, add Ts-Cl in batches at low temperature, and monitor the reaction progress by TCL until the reaction solution becomes clear.
[0008] Step 2: extracting, concentrating, recrystallizing, stirring, washing and drying the reaction solution to finally obtain the product Boc-His (Ts).
[0009] Preferably, the volume ratio of THF to water in the THF solvent is 2:1.
[0010] Preferably, the base is K2CO3, and the mixing ratio of Boc-His and K2CO3 is equimolar.
[0011] Preferably, the low temperature is between 0-10°C.
[0012] Preferably, the mixing ratio of Boc-His and Ts-Cl is equimolar.
[0013] Preferably, during the extraction, a certain volume of water and EA are added to the reaction solution to adjust the pH to alkaline to obtain a water layer, and then EA is added to adjust the pH to acidic to obtain an organic layer.
[0014] Preferably, during the concentration, THF and PET are added to the concentrated solution in a ratio of 1:3, and then the concentrated solution is allowed to stand overnight to obtain a pure Boc-His (Ts) product.
[0015] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:
[0016] 1. The present invention adopts a cheap starting material and prepares Boc-His (Ts) with a content of more than 99% through simple operation, with high yield and low production cost.
[0017] 2. The present invention can effectively separate and purify the target product through simple extraction, concentration and recrystallization steps combined with an alkaline-adjusted extraction method, thereby reducing operational complexity and improving production efficiency.
[0018] 3. The present invention adopts an equimolar ratio of reactants and a reasonable concentration method, and the final Boc-His (Ts) product obtained has a high yield and excellent purity, and is suitable for application in the fields of medicine and biochemistry.
[0019] 4. The process of the present invention does not involve heavy metal ions, is environmentally friendly, does not involve cumbersome handling, is simple to operate, and is safer and more effective. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 Flow chart for preparing Boc-His(Ts) for the present invention;
[0021] Figure 2 This is a schematic diagram of the HPLC test results of Example 2 of the present invention;
[0022] Figure 3 This is a schematic diagram of the HPLC test results of Example 3 of the present invention;
[0023] Figure 4 This is a schematic diagram of the HPLC test results of Example 4 of the present invention;
[0024] Figure 5 This is a schematic diagram of the HPLC test results of Example 5 of the present invention; DETAILED DESCRIPTION
[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0026] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0027] Embodiment 1:
[0028] The amino acid derivative involved in this patent is taken as Boc-His (Ts) as an example, and the protective reagent is taken as Ts-Cl as an example to illustrate this patent.
[0029] A method for preparing an amino acid derivative containing a protected side chain amino group, wherein the amino acid derivative is Boc-His (Ts), and the preparation method comprises the following steps:
[0030] Step 1: Dissolve Boc-His in THF solution, add alkali to adjust the pH to alkaline, add Ts-Cl in batches at low temperature, and monitor the reaction progress by TCL until the reaction solution becomes clear.
[0031] THF as a solvent has good dissolving ability and can effectively dissolve Boc-His and improve reaction efficiency; promoting the reaction of Ts-Cl by an alkaline environment can improve the selectivity and yield of the product; carrying out the reaction at a low temperature can reduce the occurrence of side reactions and ensure the purity of the product; using thin layer chromatography (TLC) to monitor the progress of the reaction is convenient for real-time evaluation of the completion of the reaction and optimization of the reaction time.
[0032] Step 2: extracting, concentrating, recrystallizing, stirring, washing and drying the reaction solution to finally obtain the product Boc-His (Ts).
[0033] The volume ratio of THF to water in the THF solvent is 2: 1. An appropriate amount of water can increase the polarity of the reaction system, help dissolve and stabilize certain intermediates, and this ratio can optimize the reaction conditions and improve the reaction efficiency and product selectivity.
[0034] The base is K2CO3, and the mixing ratio of Boc-His and K2CO3 is equimolar. K2CO3 is a mild base that can effectively promote the reaction without introducing too many side reactions. The equimolar ratio can ensure the completeness of the reaction and avoid the interruption of the reaction caused by insufficient base.
[0035] The low temperature is between 0-10° C. Low temperature can significantly reduce the side reactions caused by heat, ensure that the reaction is more selective, and the reaction intermediates are more stable at low temperature, thereby increasing the yield of the final product.
[0036] The mixing ratio of Boc-His and Ts-Cl is equimolar. The ratio helps to ensure complete reaction and avoid the presence of unreacted substances, thereby improving purity and yield.
[0037] During the extraction, a certain volume of water and EA are added to the reaction solution to adjust the pH to alkaline to obtain a water layer, and then EA is added to adjust the pH to acidic to obtain an organic layer. The use of EA can increase the solubility of the target product in the organic phase, thereby increasing the extraction rate. By adjusting the pH to allow different components to be distributed in the water layer and the organic layer, the target product can be efficiently separated.
[0038] During the concentration, THF and PET are added to the concentrate in a ratio of 1:3, and then the concentrate is allowed to stand overnight to obtain a pure Boc-His (Ts) product. The combination of THF and PET can optimize the crystallization conditions of the product, increase the yield of the pure product, and the long standing time facilitates more complete crystallization and improves the purity of the final product.
[0039] Embodiment 2:
[0040] Weigh 1.0 mol of Boc-His254.2g and dissolve it in 1L THF and 0.5L H2o, add K2CO3138.6g, control the temperature at 0-10°C under ice bath, add 1 mol of Ts-Cl190.7g in batches during stirring, restore to room temperature after addition, monitor the reaction progress by TLC, and obtain the target product Boc-His (Ts) after the reaction is complete; add 500ml of water and 500ml of EA solution to the Boc-His (Ts) solution, and adjust the pH to weak alkalinity. Extract and separate to obtain the water layer. Repeat three times, add EA to the aqueous phase, and adjust the pH to weak acidity to obtain the organic layer, and repeat three times. Concentrate the organic phase to a certain volume, add 100ml THF and 300ml PET, let it stand overnight, and obtain the pure Boc-His (Ts) by recrystallization, stirring, washing and suction filtration, and send the sample for detection after drying. 390.6 g of Boc-His (Ts) was obtained with a yield of 95.5%. Figure 2 As shown, the content was 99.65% by HPLC.
[0041] Embodiment 3:
[0042] Weigh 1.0 mol of Boc-His254.2g and dissolve it in 1L THF and 0.5L H2o, add Na2CO3105.9g, control the temperature at 0-10°C under ice bath, add 1 mol of Ts-Cl190.7g in batches during stirring, restore to room temperature after addition, monitor the reaction progress by TLC, and obtain the target product Boc-His (Ts) after the reaction is complete; add 500ml of water and 500ml of EA solution to the Boc-His (Ts) solution, and adjust the pH to weak alkalinity. Extract and separate to obtain the water layer. Repeat three times, add EA to the aqueous phase, and adjust the pH to weak acidity to obtain the organic layer, and repeat three times. Concentrate the organic phase to a certain volume, add 100ml THF and 300ml PET, let it stand overnight, and obtain the pure Boc-His (Ts) by recrystallization, stirring, washing and suction filtration, and send the sample for detection after drying. 369.3 g of Boc-His(Ts) was obtained with a yield of 90.3%. Figure 3 As shown, the content was 99.68% detected by HPLC.
[0043] Embodiment 4:
[0044] Weigh 1.0 mol of Boc-His254.2g and dissolve it in 1L THF and 0.5L H2o, add K2CO3105.9g, control the temperature at 0-10°C under ice bath, add 1.2 mol of Ts-Cl228.8g in batches during stirring, restore to room temperature after addition, monitor the reaction progress by TLC, and obtain the target product Boc-His (Ts) after the reaction is complete; add 500ml of water and 500ml of EA solution to the Boc-His (Ts) solution, and adjust the pH to weak alkalinity. Extract and separate to obtain the water layer. Repeat three times, add EA to the aqueous phase, and adjust the pH to weak acidity to obtain the organic layer, and repeat three times. Concentrate the organic phase to a certain volume, add 100ml THF and 300ml PET, let it stand overnight, and obtain the pure Boc-His (Ts) by recrystallization, stirring, washing and suction filtration, and send the sample for detection after drying. 372.6 g of Boc-His(Ts) was obtained with a yield of 91.1%. Figure 4 As shown, the content was 99.68% detected by HPLC.
[0045] Embodiment 5:
[0046] Weigh 1.0 mol of Boc-His254.2g and dissolve it in 1L THF and 0.5L H2o, add K2CO3105.9g, control the temperature at 0-10°C under ice bath, add 1.5 mol of Ts-Cl286.05g in batches during stirring, restore to room temperature after addition, monitor the reaction progress by TLC, and obtain the target product Boc-His (Ts) after the reaction is complete; add 500ml of water and 500ml of EA solution to the Boc-His (Ts) solution, and adjust the pH to weak alkalinity. Extract and separate to obtain the water layer. Repeat three times, add EA to the aqueous phase, and adjust the pH to weak acidity to obtain the organic layer, and repeat three times. Concentrate the organic phase to a certain volume, add 100ml THF and 300ml PET, let it stand overnight, and obtain the pure Boc-His (Ts) by recrystallization, stirring, washing and suction filtration, and send the sample for detection after drying. 362.1 g of Boc-His(Ts) was obtained with a yield of 88.5%. Figure 5 As shown, the content was 99.75% by HPLC.
[0047] The above description is only a preferred embodiment of the present application, and is only selected as a control condition. The impact on product yield and quality does not mean that this patent technology has only been verified by four experiments.
[0048] Comparing Example 2 with Example 3, during the experiment, alkaline hydrogenation with K2CO3 was the best compared with Na2CO3, which could achieve the highest yield and better product detection data.
[0049] Comparing Example 2, Example 4 and Example 5, the mixing ratio of Boc-His and Ts-Cl is equimolar, which is the optimal choice, reducing the loss of the product during the post-treatment process, while saving the cost of raw materials, making the product yield higher and the test data in various aspects better.
[0050] Through the analysis of the above comparative experiments, it is concluded that when K2CO3 is selected as the alkaline reagent and the mixing ratio of the raw materials Boc-His and Ts-Cl is equimolar, the yield of Boc-His (Ts) is higher and has a higher purity.
[0051] It is worth noting that Ts in the foregoing text and Tos in the accompanying drawings are abbreviations of the same substance, which does not affect the understanding of the synthesis method of the present invention by those skilled in the art.
[0052] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A method for preparing an amino acid derivative containing a protected side chain amino group, characterized in that: The amino acid derivative is Boc-His (Ts), and the preparation method comprises the following steps: Step 1: Dissolve Boc-His in THF solution, add alkali to adjust the pH to alkaline, add Ts-Cl in batches at low temperature, and monitor the reaction progress by TCL until the reaction solution becomes clear; Step 2: extracting, concentrating, recrystallizing, stirring, washing and drying the reaction solution to finally obtain the product Boc-His (Ts).
2. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: The volume ratio of THF to water in the THF solvent is 2:
1.
3. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: The base is K2CO3, and the mixing ratio of Boc-His and K2CO3 is equimolar.
4. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: The low temperature is between 0-10°C.
5. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: The mixing ratio of Boc-His and Ts-Cl is equimolar.
6. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: During the extraction, a certain volume of water and EA are added to the reaction solution to adjust the pH to alkaline to obtain a water layer, and then EA is added to adjust the pH to acidic to obtain an organic layer.
7. The method for preparing an amino acid derivative containing a protected side chain amino group according to claim 1, characterized in that: During the concentration, THF and PET were added to the concentrate in a ratio of 1:3, and then the concentrate was allowed to stand overnight to obtain a pure Boc-His (Ts) product.