A class of lipid vitamins based on amino acid structure and their synthesis methods

Abstract

This invention discloses a class of lipid vitamins based on amino acid structures and their synthesis method. The head of the lipid vitamin consists of one or more amino acids, and the tail consists of a hydrophobic vitamin and a fatty acid chain. The molecular weight of the amino acid lipid vitamin is 1000-2000 Da. The synthesis method is a solid-phase synthesis method based on peptide synthesis. First, the carbon terminus of the amino acid is linked to a 2-chlorotriphenylmethyl chloride resin. Then, a condensation-washing-deprotection-washing cycle is performed. Finally, the vitamin and fatty acid chain are coupled at the nitrogen terminus to obtain a class of lipid vitamins based on amino acid structures. The synthesized lipid vitamin is removed from the resin using a lysis buffer, and soluble byproducts in the organic solvent are removed using a non-polar solvent. This method is simple to operate, produces high-purity products, requires fewer complex control factors, and has strong reproducibility.

Description

Technical Field

[0001] This invention belongs to the field of nanomedicine, and specifically relates to a class of lipid vitamins and their synthesis methods. Background Technology

[0002] Vitamins are essential micronutrients for living organisms, playing a crucial role in regulating the normal physiological activities of tissues and cells. Their biological activities encompass multiple aspects, including cell proliferation and differentiation, growth and development, morphogenesis, metabolism, and the regulation of homeostasis. As a vital component of life, vitamins not only play a crucial role in the body's development but also participate in a complex regulatory network that maintains the overall health of the organism. By regulating the cell life cycle and influencing metabolic pathways, vitamins ensure that organisms can effectively adapt to and maintain internal and external balance under various environmental conditions.

[0003] However, the unsaturated bonds, relatively poor stability, large molecular weight, and relatively low bioavailability of fat-soluble vitamins pose challenges to their metabolism and utilization in the body. First, the presence of unsaturated bonds increases the chemical instability of vitamin molecules, making them more susceptible to environmental factors such as oxidation. Second, the relatively large molecular weight of fat-soluble vitamins affects their efficiency in absorption during the digestive tract. Because the absorption and transport of these molecules by the body is more complex, their bioavailability is relatively lower than that of water-soluble vitamins. This means that only a portion of ingested fat-soluble vitamins can be effectively absorbed and utilized, while the remainder is excreted or cannot fully participate in the body's metabolic processes.

[0004] Liposome drug delivery systems, with their phospholipid bimolecular structure highly similar to cell membranes, good stability, and biocompatibility, have been shown to enhance drug penetration into biological membranes and effectively load both hydrophobic and lipophilic drugs. To date, reported vitamin liposomes have primarily been liposome suspensions, which have some limitations. First, liposome suspensions are unstable during storage and transportation, making drug release and efficacy unpredictable. Second, for some highly sensitive vitamin drugs, the preparation process of liposome suspensions may lead to a decrease in drug activity. Therefore, we investigated a class of amino acid lipid vitamins synthesized using solid-phase peptides, characterized by controllable structure, uniform dispersion, and high loading capacity. Compared to traditional physically encapsulated vitamin liposomes, lipid vitamins utilize amino acids as a biological scaffold, increasing biocompatibility and colloidal stability while avoiding the uneven dispersion problems caused by hydrophobic structures. Summary of the Invention

[0005] The purpose of this invention is to provide a class of lipid vitamins based on amino acid structures;

[0006] Another object of the present invention is to provide a method for synthesizing lipid vitamins based on amino acid structures;

[0007] Amino acids, lipids, and vitamins have the following characteristics:

[0008] (1) The head is composed of hydrophilic amino acids, and the tail is composed of hydrophobic fatty acid chains and vitamins;

[0009] (2) It has a specific molecular weight range: 1000-2000 Da.

[0010] A method for synthesizing a class of lipid vitamins based on amino acid structures is characterized by the following steps: solid-phase polypeptide synthesis is employed, in which an amino acid at the carbon terminus is linked to a 2-chlorotriphenylmethyl chloride resin; the synthesis is carried out through a condensation-washing-deprotection-washing cycle, with the nitrogen terminus retained at the end providing a coupling site for the vitamin and the fatty acid chain; further, a hydrophobic lipid tail is coupled via an amide reaction to obtain a class of lipid vitamins based on amino acid structures; the synthesized lipid vitamins are cleaved from the resin using a lysis buffer, and soluble byproducts in the organic solvent are removed using a nonpolar solvent.

[0011] The synthesis method of lipid vitamins based on amino acid structure includes the following steps:

[0012] (1) Amino acid structure fixation: The resin was placed in a syringe reactor and pre-swollen in anhydrous dichloromethane (DCM) for 20-30 minutes. The reaction solution was discarded, and then the first amino acid reaction solution was added. The reaction was carried out at room temperature for 1-2 hours. The reaction solution was then removed and washed with N,N-dimethylformamide (DMF) and DCM to obtain the resin with fixed amino acid structure, namely resin-1.

[0013] (2) Blocking of active chlorine functional groups: The resin prepared in step (1) was reacted with a blocking solution containing methanol at room temperature for 30-40 minutes, washed with DMF and DCM, and then vacuum dried for 24-48 hours to obtain resin blocked with active chlorine functional groups, namely resin-2. The amino acid loading rate on resin-2 was measured.

[0014] (3) Amino acid structure expansion: The resin-2 prepared in step (2) was pre-swollen in anhydrous DCM. After discarding the reaction solution, the operation was repeated n times (1≤n≤20). The operation steps are as follows: add deprotection solution, react at room temperature for 10-20 minutes to remove the temporary protecting groups of amino acids, then add amino acid reaction solution, react at room temperature for 1-2 hours, then remove the reaction solution, wash with DMF and DCM, and finally obtain resin with n+1 fixed amino acid structures, i.e. resin-3;

[0015] (4) Fatty acid grafting: Mix resin-3 from step (3) with the deprotection solution and react at room temperature for 10-20 minutes. After discarding the reaction solution, add fatty acid reaction solution and react at room temperature for 24-36 hours to complete fatty acid grafting and obtain fatty acid grafted amino acid resin, i.e., resin-4.

[0016] (5) Vitamin grafting: Mix the resin from step (4) with the deprotecting solution of 2-acetyl dimethyl ketone (Dde) protecting group, react at room temperature for 2-3 minutes, repeat 10-20 times, discard the reaction solution, add vitamin reaction solution, react at room temperature in the dark for 4-12 hours, and then remove the reaction solution to complete the vitamin grafting and obtain vitamin grafted amino acid resin, namely resin-5.

[0017] (6) Separation of lipid vitamins: The resin from step (5) is mixed with the lysis solution pre-cooled at -10 to -20°C for 1-2 hours, and reacted at room temperature in the dark for 20-30 minutes. The reaction solution is collected to obtain a lipid vitamin solution.

[0018] (7) Collect the reaction solution from step (6), mix it with the precipitate, centrifuge at 0-4℃ under 4000-6000 rpm, collect the precipitate, and then freeze-dry it under vacuum for 24-48h to obtain lipid vitamins based on amino acid structure.

[0019] Wherein, the resin mentioned in step (1) is 2-chlorotrimethylyl chloride resin; the first amino acid reaction solution mentioned in step (1) is a mixture of amino acid protected by methoxycarbonyl (Fmoc), N,N-diisopropylethylamine (DIPEA) and DCM, the molar ratio of amino acid to DPEA is 1:2-3, the amount of amino acid used is 0.4-0.8 mmol / g compared with the resin in step (1), and the amount of DCM used is 8-12 mL / g;

[0020] The sealing solution in step (2) is a mixture of DCM, methanol and DIPEA in a volume ratio of 80-90:10-20:4-5. The amount of the mixture used is 8-12 mL / g compared with resin-1 in step (1). Following the above operation, the amino acid loading on resin-2 is 0.15-0.35 mmol / g.

[0021] The deprotection solution in step (3) is a mixture of piperidine and DCM, with a volume ratio of 1:3-6. The amount of the mixture used is 10-20 mL / g compared to resin-2 in step (2). The amino acid reaction solution in step (3) is a mixture of amino acids, DIPEA, hydroxybenzotriazole (HOBt), benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate (PyBop), DCM and DMF. The molar ratio of the amount of amino acids, DIPEA, HOBt, and PyBop to the amount of amino acids loaded on resin-2 is 2-3:4-5:2-3:2-3:0.5-1.5. The volume ratio of DCM and DMF is 1:1-3. The amount of DCM used is 10-20 mL / g.

[0022] The fatty acid reaction solution described in step (4) is a mixture of fatty acids, DCM, DIPEA, HOBt, PyBop, and DMF. The molar ratio of the amount of fatty acids, DIPEA, HOBt, and PyBop to the amino acids loaded on resin-2 is 2-3:4-5:2-3:2-3:0.5-1.5. The volume ratio of DCM to DMF is 1:1-3. The amount of DCM compared to resin-2 is 10-20 mL / g.

[0023] The Dde deprotection solution mentioned in step (5) is a mixture of hydrazine hydrate and DCM, with a volume ratio of 1:40-60, and the amount of the mixture used is 30-60 mL / g compared with resin-2 in step (2); the vitamin reaction solution mentioned in step (5) is a mixture of vitamins, DIPEA, HOBt, PyBop, DCM, and DMF, with a molar ratio of vitamins, DIPEA, HOBt, PyBop to amino acids loaded on resin-2 of 2-3:4-5:2-3:2-3:0.5-1.5, a volume ratio of DCM to DMF of 1:1-3, and the amount used is 10-20 mL / g compared with resin-2;

[0024] The lysis solution in step (6) is a mixture of trifluoroacetic acid, deionized water, and triisopropylsilane in a volume ratio of 90-95:2.5-5:2.5-5, and the amount of the mixture used is 80-120 mL / g compared to resin-5; the precipitate in step (7) is a mixture of methyl tert-butyl ether and n-hexane in a volume ratio of 1:1-3, and the amount of the mixture used is 200-400 mL / g compared to resin-5.

[0025] The discarded reaction liquid in the above steps is all solid-liquid separation using a syringe reactor. The room temperature condition mentioned refers to the ambient temperature, which is not controlled during the reaction.

[0026] Furthermore, the amino acid structure fixation involves attaching the carbon-terminal amino acid to the resin via a linker arm. Specifically, 0.5-1 g of 2-chlorotriphenylmethyl chloride resin is placed in a 5-15 mL syringe reactor and pre-swollen in anhydrous DCM for 30-60 minutes, after which the DCM is discarded. Then, the first Fmoc-protected amino acid reaction solution is added and incubated at room temperature for 1-2 hours. The components of the amino acid reaction solution include the Fmoc-protected amino acid (Fmoc-amino acid), DCM, and DIPEA (DIPEA). The reaction solution is removed and washed with DCM and DMF to obtain resin-1. The washing steps are: first wash with DMF 3-5 times, then wash with DCM 3-5 times.

[0027] Resin-1 was incubated with a blocking solution containing methanol (DCM, methanol, and DIPEA) at room temperature for 30-40 minutes to block residual active chlorine functional groups. The resin was then washed again and vacuum dried 3-5 times to obtain Resin-2. The amino acid loading on Resin-2 was measured.

[0028] Take 100-200 mg of resin-2 and add it to 5-8 mL of DCM for pre-swelling for 30-60 minutes, then discard the DCM. Repeat the following operation n (1≤n≤20) times: add Fmoc deprotection solution, react for 10-20 minutes, then discard the reaction solution. Repeat 3-5 times to remove the protecting group. The Fmoc deprotection solution is a 20% v / v piperidine DCM solution. Wash resin-2 and couple it with Fmoc-amino acid. Its components include Fmoc-amino acid, DCM, DIPEA, HOBt, PyBop, and DMF to obtain resin-3.

[0029] Subsequently, stearic acid, oleic acid, linoleic acid, linolenic acid, cholic acid, or hydroxy-modified stearic acid solution is added as the hydrophobic fatty tail of the lipid. Specifically, a fatty acid reaction solution is added, and the mixture is incubated at room temperature for 24-36 hours. After the reaction, the mixture is washed to remove the reaction solution, yielding resin-4. The fatty acid reaction solution consists of fatty acids, DCM, DIPEA, HOBt, PyBop, and DMF.

[0030] The semi-permanent protecting group Dde on the amino acid side chain was removed, and carboxylated vitamins were added. Specifically, the protecting group at the ε-amine of the carbon-terminal amino acid was removed by reacting with 8-10 mL of Dde deprotection solution for 2-3 minutes, repeated 15-20 times. The Dde deprotection solution was a 2% v / v hydrazine hydrate DCM solution. Then, vitamin reaction solution was added, and the reaction was carried out at room temperature in the dark for 4-12 hours. After the reaction was completed, the residue was washed again to remove the residual reaction solution, thus obtaining resin-5.

[0031] Finally, the lysis buffer was added and reacted in the dark for 20-30 minutes to remove the tert-butyloxycarbonyl (Boc) protecting group and remove the synthesized lipid vitamins from resin-5. Then, it was immediately added to the precipitation solution, which was a mixture of methyl tert-butyl ether and n-hexane. After centrifugation for 10-20 minutes, soluble reaction byproducts were removed, the precipitate was collected and freeze-dried under vacuum to obtain a series of lipid vitamins based on amino acid structures.

[0032] This invention is the first to synthesize a class of lipid vitamins based on amino acid structures, which exhibits better biocompatibility and colloidal stability (no significant change in particle size distribution within one week) compared to traditional physically encapsulated liposomes. Figure 4 Amino acid bioscaffolds, with various chemically modified structures, can achieve multiple special effects such as antibody conjugation, improving drug targeting in vivo. They also solve the problem of drug loading limitations, achieving efficient and controllable vitamin loading. Furthermore, by adjusting the lipid-vitamin ratio, the uneven dispersion problem caused by hydrophobic structures in physical encapsulation can be avoided. Attached Figure Description

[0033] Figure 1 : Chemical structure diagram of Example 1 of the present invention.

[0034] Figure 2 Mass spectrum of Example 1 of the present invention.

[0035] Figure 3 Transmission electron microscope images of liposomes (a) and vitamin liposomes (b) of Example 1 of the present invention.

[0036] Figure 4 Particle size tests (0, 3, and 7 days) of liposomes (a) and vitamin liposomes (b) synthesized in Example 1 of this invention. Detailed Implementation

[0037] Example 1

[0038] (1) 1 g of 2-chlorotriphenylmethyl chloride resin was placed in a 15 mL syringe reactor and pre-swollen in 5 mL of calcium chloride-dried DCM for 30 minutes, after which the DCM was discarded. 0.45 mmol of Boc-protected Fmoc-lysine (Fmoc-Lys(Boc)-OH) and 0.9 mmol of DIPEA were dissolved in 5 mL of DCM, drawn into a syringe, and incubated at room temperature for 1 h. Subsequently, the reaction solution was removed, and the resin was washed with DMF and DCM in the following order: three washes with DMF followed by three washes with DCM. 8 mL of DCM, 1.5 mL of methanol, and 0.5 mL of DIPEA were mixed, drawn into a syringe, and incubated at room temperature for 30 minutes. The resin was washed again with DMF and DCM and then vacuum dried. The amino acid loading on the resin was measured to be 0.3 mmol / g.

[0039] (2) Take 100 mg of the resin obtained in step (1), aspirate it into 5 mL of DCM for pre-swelling for 30 minutes, and discard the DCM. Take 20% v / v piperidine DCM solution, react for 15 minutes, and discard the reaction solution. Repeat 3 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0040] (3) Dissolve 0.12 mmol Dde-protected Fmoc-lysine Fmoc-Lys(Dde)-OH and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. After mixing, aspirate the solution into the syringe used in step (2). After reacting for 1 h, discard the reaction solution and wash the resin with DMF and DCM. Take 20% v / v piperidine DCM solution, react for 15 minutes, discard the reaction solution, and repeat 3 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0041] (4) Dissolve 0.12 mmol stearic acid and 0.24 mmol DIPEA in 1 mL DCM, and 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. Mix well and aspirate into the syringe used in step (3). After reacting for 24 h, discard the reaction solution and wash the resin with DMF and DCM. Take 5 mL of 2% v / v hydrazine hydrate DCM solution and react for 2 minutes. Remove the reaction solution and repeat 15 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0042] (5) Dissolve 0.12 mmol D-α-vitamin E succinate and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. After mixing, aspirate the solution into the syringe used in step (4). After reacting in the dark for 4 hours, discard the reaction solution and wash the resin with DMF and DCM.

[0043] (6) Mix 9.5 mL of trifluoroacetic acid, 0.25 mL of water, and 0.25 mL of triisopropylsilane, aspirate into a syringe, and react at room temperature in the dark for 20 minutes. Take 40 mL of a mixture of methyl tert-butyl ether and n-hexane pre-cooled at -20 °C for 1 h (volume ratio 1:1), centrifuge at 4 °C and 4000 rpm for 15 minutes, remove the supernatant, redissolve in water, and freeze under vacuum at -80 °C for 24 h to obtain lipid vitamins based on amino acid structure.

[0044] (7) Take the synthesized lipid vitamins and mix them with cholesterol in chloroform solvent. Remove the solvent by rotary evaporation at 60°C in a round-bottom flask, and vacuum dry overnight at room temperature. Then add PBS and treat under sonication for 30 min to obtain liposome solution (see attached). Figure 3And it can remain relatively stable within a week (see appendix) Figure 4 ).

[0045] Example 2

[0046] (1) 1 g of 2-chlorotriphenylmethyl chloride resin was placed in a 15 mL syringe reactor and pre-swollen in 5 mL of calcium chloride-dried DCM for 30 minutes, then the DCM was discarded. 0.45 mmol Fmoc-Lys(Dde)-OH and 0.9 mmol DIPEA were dissolved in 5 mL of DCM, drawn into a syringe, and incubated at room temperature for 1 h. Subsequently, the reaction solution was removed, and the resin was washed with DMF and DCM in the following order: three washes with DMF followed by three washes with DCM. 8 mL of DCM, 1.5 mL of methanol, and 0.5 mL of DIPEA were mixed, drawn into a syringe, and incubated at room temperature for 30 minutes. The resin was washed again with DMF and DCM and then vacuum dried. The amino acid loading on the resin was measured to be 0.3 mmol / g resin.

[0047] (2) Take 100 mg of the resin obtained in step (1), aspirate it into 5 mL of DCM for pre-swelling for 30 minutes, and discard the DCM. Take 20% v / v piperidine DCM solution, react for 15 minutes, and discard the reaction solution. Repeat 3 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0048] (3) Dissolve 0.12 mmol oleic acid and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. Mix well and aspirate into the syringe used in step (2). After reacting for 24 h, discard the reaction solution and wash the resin with DMF and DCM. Take 5 mL of 2% v / v hydrazine hydrate DCM solution and react for 2 minutes. Remove the reaction solution and repeat 15 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0049] (4) Dissolve 0.12 mmol L-L-threo-hex-2-eneic acid 1,4-lactone (carboxylated vitamin C) and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. After mixing, aspirate the solution into the syringe used in step (3). After reacting in the dark for 4 h, discard the reaction solution and wash the resin with DMF and DCM.

[0050] (5) Mix 9.5 mL of trifluoroacetic acid, 0.25 mL of water, and 0.25 mL of triisopropylsilane, aspirate into a syringe, and react at room temperature in the dark for 20 minutes. Take 40 mL of a mixture of methyl tert-butyl ether and n-hexane pre-cooled at -20 °C for 1 h (volume ratio 1:1), centrifuge at 4 °C and 4000 rpm for 15 minutes, remove the supernatant, redissolve in water, and freeze under vacuum at -80 °C for 24 h to obtain lipid vitamins based on amino acid structure.

[0051] Example 3

[0052] (1) 1 g of 2-chlorotriphenylmethyl chloride resin was placed in a 15 mL syringe reactor and pre-swollen in 5 mL of calcium chloride-dried DCM for 30 minutes, then the DCM was discarded. 0.45 mmol Fmoc-Lys(Dde)-OH and 0.9 mmol DIPEA were dissolved in 5 mL of DCM, drawn into a syringe, and incubated at room temperature for 1 h. Subsequently, the reaction solution was removed, and the resin was washed with DMF and DCM in the following order: three washes with DMF followed by three washes with DCM. 8 mL of DCM, 1.5 mL of methanol, and 0.5 mL of DIPEA were mixed, drawn into a syringe, and incubated at room temperature for 30 minutes. The resin was washed again with DMF and DCM and then vacuum dried. The amino acid loading on the resin was measured to be 0.3 mmol / g resin.

[0053] (2) Take 100 mg of the resin obtained in step (1), aspirate it into 5 mL of DCM for pre-swelling for 30 minutes, and discard the DCM. Take 20% v / v piperidine DCM solution, react for 15 minutes, and discard the reaction solution. Repeat 3 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0054] (3) Dissolve 0.12 mmol Fmoc-Lys(Boc)-OH and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. After mixing, aspirate the solution into the syringe used in step (2). After reacting for 1 h, discard the reaction solution and wash the resin with DMF and DCM. Take 20% v / v piperidine DCM solution, react for 15 minutes, then discard the reaction solution. Repeat 3 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0055] (4) Dissolve 0.12 mmol stearic acid and 0.24 mmol DIPEA in 1 mL DCM, and 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. Mix well and aspirate into the syringe used in step (3). After reacting for 24 h, discard the reaction solution and wash the resin with DMF and DCM. Take 5 mL of 2% v / v hydrazine hydrate DCM solution and react for 2 minutes. Remove the reaction solution and repeat 15 times. Remove the reaction solution and wash the resin with DMF and DCM.

[0056] (5) Dissolve 0.12 mmol retinoic acid (carboxylated vitamin A) and 0.24 mmol DIPEA in 1 mL DCM, and dissolve 0.12 mmol HOBt and 0.12 mmol PyBop in 1 mL DMF. After mixing, draw the solution into the syringe from step (4). After reacting in the dark for 4 hours, discard the reaction solution and wash the resin with DMF and DCM.

[0057] (6) Mix 9.5 mL of trifluoroacetic acid, 0.25 mL of water, and 0.25 mL of triisopropylsilane, aspirate into a syringe, and react at room temperature in the dark for 20 minutes. Take 40 mL of a mixture of methyl tert-butyl ether and n-hexane pre-cooled at -20 °C for 1 h (volume ratio 1:1), centrifuge at 4 °C and 4000 rpm for 15 minutes, remove the supernatant, redissolve in water, and freeze under vacuum at -80 °C for 24 h to obtain lipid vitamins based on amino acid structure.

[0058] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing lipid vitamins based on amino acid structures, characterized in that, The amino acid backbone is fixed with chlorinated resin, and then the residual active chlorinated functional groups are blocked with a blocking solution. After removing the protecting groups of the amino acid with a deprotecting solution, it is mixed with amino acid reaction solution, fatty acid reaction solution, and vitamin reaction solution respectively to obtain the expansion of the amino acid backbone and the grafting of vitamin and fatty acid chains. Then, the lipid vitamins and resin are separated using a lysis buffer. The specific conditions and steps are as follows: (1) Amino acid structure fixation: The resin was placed in a syringe reactor and pre-swollen in anhydrous dichloromethane for 20-30 minutes. The reaction solution was discarded, and then the first amino acid reaction solution was added. The reaction was carried out at room temperature for 1-2 hours. The reaction solution was then removed and washed with N,N-dimethylformamide and dichloromethane to obtain the resin with fixed amino acid structure, namely resin-1. (2) Blocking of active chlorine functional groups: The resin prepared in step (1) was reacted with a blocking solution containing methanol at room temperature for 30-40 minutes, washed with N,N-dimethylformamide and dichloromethane, and then vacuum dried for 24-48 hours to obtain resin blocked with active chlorine functional groups, namely resin-2, and the amino acid loading rate was measured. (3) Amino acid structure expansion: The resin-2 prepared in step (2) was pre-swollen in anhydrous dichloromethane. After discarding the reaction solution, the operation was repeated n times (1≤n≤20). The operation steps are as follows: add deprotection solution, react at room temperature for 10-20 minutes to remove the temporary protecting groups of amino acids, then add amino acid reaction solution, react at room temperature for 1-2 hours, then remove the reaction solution, wash with N,N-dimethylformamide and dichloromethane, and finally obtain resin with n+1 fixed amino acid structures, i.e. resin-3; (4) Fatty acid grafting: Mix resin-3 from step (3) with the deprotection solution and react at room temperature for 10-20 minutes. After discarding the reaction solution, add fatty acid reaction solution and react at room temperature for 24-36 hours to complete fatty acid grafting and obtain fatty acid grafted amino acid resin, i.e., resin-4. (5) Vitamin grafting: Mix the resin from step (4) with the 2-acetyl dimethyl ketone deprotecting solution, react at room temperature for 2-3 minutes, repeat 10-20 times, discard the reaction solution, add vitamin reaction solution, react at room temperature in the dark for 4-12 hours, and then remove the reaction solution to complete the vitamin grafting and obtain vitamin grafted amino acid resin, i.e., resin-5. (6) Separation of lipid vitamins: The resin from step (5) is mixed with the lysis solution pre-cooled at -10~-20℃ for 1-2 hours, and reacted at room temperature in the dark for 20-30 minutes. The reaction solution is collected to obtain a lipid vitamin solution. (7) Collect the reaction solution from step (6), mix it with the precipitate, centrifuge at 0-4℃ under 4000-6000 rpm, collect the precipitate, and then freeze-dry it under vacuum for 24-48h to obtain lipid vitamins based on amino acid structure. Wherein, the resin mentioned in step (1) is 2-chlorotrimethylyl chloride resin; the first amino acid reaction solution mentioned in step (1) is a mixture of amino acid, N,N-diisopropylethylamine and dichloromethane, the molar ratio of amino acid and N,N-diisopropylethylamine is 1:2-3, the amount of amino acid used is 0.4-0.8 mmol / g compared with the resin in step (1), and the amount of dichloromethane used is 8-12 mL / g; The sealing liquid in step (2) is a mixture of dichloromethane, methanol and N,N-diisopropylethylamine, with a volume ratio of 80-90:10-20:4-5. The amount of the mixture used is 8-12 mL / g compared with resin-1 in step (1). The deprotection solution in step (3) is a mixture of piperidine and dichloromethane, with a volume ratio of 1:3-6. The amount of the mixture is 10-20 mL / g compared to resin-2 in step (2). The amino acid reaction solution in step (3) is a mixture of amino acids, N,N-diisopropylethylamine, hydroxybenzotriazole, benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate, dichloromethane, and N,N-dimethylformamide. The molar ratio of the amount of amino acids, N,N-diisopropylethylamine, hydroxybenzotriazole, and benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate to the amount of amino acids loaded on resin-2 is 2-3:4-5:2-3:2-3:0.5-1.

5. The volume ratio of dichloromethane to N,N-dimethylformamide is 1:1-3. The amount of dichloromethane is 10-20 mL / g. The fatty acid reaction solution in step (4) is a mixture of fatty acids, dichloromethane, N,N-diisopropylethylamine, hydroxybenzotriazole, benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate, and N,N-dimethylformamide. The molar ratio of the amount of fatty acids, N,N-diisopropylethylamine, hydroxybenzotriazole, and benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate to the amino acids loaded on resin-2 is 2-3:4-5:2-3:2-3:0.5-1.

5. The volume ratio of dichloromethane to N,N-dimethylformamide is 1:1-3. The amount of dichloromethane is 10-20 mL / g compared to resin-2. The 2-acetyl dimethyl ketone deprotecting solution in step (5) is a mixture of hydrazine hydrate and dichloromethane in a volume ratio of 1:40-60, and the amount of the mixture used is 30-60 mL / g compared to resin-2 in step (2); the vitamin reaction solution in step (5) is vitamin, N,N-diisopropylethylamine, hydroxybenzotriazole, benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate, and dichloromethane. The molar ratio of vitamin, N,N-diisopropylethylamine, hydroxybenzotriazole, benzotriazole-1-yl-oxytripyrrolidinephosphonium-hexafluorophosphate and amino acids loaded on resin-2 is 2-3:4-5:2-3:2-3:0.5-1.5, and the volume ratio of dichloromethane and N,N-dimethylformamide is 1:1-3. The dosage is 10-20 mL / g compared with resin-2. The lysis solution in step (6) is a mixture of trifluoroacetic acid, deionized water, and triisopropylsilane in a volume ratio of 90-95:2.5-5:2.5-5, and the amount of the mixture used is 80-120 mL / g compared to resin-2; the precipitate in step (7) is a mixture of methyl tert-butyl ether and n-hexane in a volume ratio of 1:1-3, and the amount of the mixture used is 200-400 mL / g compared to resin-2. All the discarded reaction solutions mentioned in the above steps are solid-liquid separations performed using a syringe reactor, and the room temperature conditions mentioned are for reactions without temperature restrictions; the amino acid mentioned is lysine, the fatty acid is stearic acid, and the vitamin is D-α-vitamin E succinate.

2. The lipid vitamin prepared by the method of claim 1.

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