2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid and preparation method and application thereof

Abstract

The invention discloses 2-amino-6-[(2-hydroxypropionyl) amino] hexanoic acid and a preparation method and application thereof, and belongs to the technical field of synthesis and utilization of small molecular compounds, methyl lactate and lysine are used as raw materials and react at the temperature of 15-35 DEG C, after the reaction is finished, a mixture is subjected to solid-liquid centrifugal separation, lower-layer solids are taken and washed with ethyl acetate, and the 2-amino-6-[(2-hydroxypropionyl) amino] hexanoic acid is obtained. And repeatedly centrifuging for three times, and drying at low temperature to obtain a milk white product 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid. According to the 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid as well as the preparation method and the application thereof, methyl lactate and lysine are subjected to direct acylation reaction at room temperature to synthesize the 2-amino-6-[(2-hydroxy propionyl) amino] hexanoic acid, and the obtained product simultaneously contains a methyl lactate structure and a lysine structure; the product is a key product of histone lysine milk acylation modification, and can be used for cardiovascular disease treatment and green chemical intermediates.

Description

Technical Field

[0001] This invention relates to the field of small molecule compound synthesis and utilization technology, and in particular to 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method and application. Background Technology

[0002] Methyl lactate is a fine chemical of significant economic value, appearing as a colorless, transparent liquid at room temperature. As a biomass-based, non-toxic, and environmentally friendly chemical, methyl lactate has wide applications in the chemical, pharmaceutical, and cosmetic industries, serving as a fragrance, coating, emulsifier, and cleaning agent. It is also an organic solvent. Furthermore, methyl lactate is non-toxic, has low volatility, and is readily biodegradable, making it suitable for use as a common green organic solvent.

[0003] Lysine is an essential amino acid for normal animal growth, playing a vital role in promoting bone growth, maintaining metabolic balance, enhancing immunity, and alleviating anxiety. Lysine has high amino reactivity and can undergo amidation reactions with carboxylic acid derivatives.

[0004] The lactylated product 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, formed by the reaction of lysine and methyl lactate, is a novel small molecule containing both methyl lactate and lysine structures. It is also a key product of histone lysine lactylation modification. For example, CHEN et al., in *Front Immunol* (Vol. 12, 2021, No. 688910), emphasized the relationship between lactate metabolism and function, as well as the evidence and importance of lactate-derived lactylation, and also discussed the therapeutic potential of lactylation, providing direction for future research. ZHANG et al., in *Nature* (Vol. 574, No. 7779, 2019, pp. 575-580), revealed the important role of histone lactylation in gene expression and metabolic regulation, providing a new perspective for understanding the function of lactate under various physiological and pathological conditions. In recent years, the role of lysine lactylation modification has attracted increasing attention, playing a crucial role in the treatment of cardiovascular diseases such as atherosclerosis, myocardial infarction, and pulmonary hypertension, and possessing enormous potential application value. Yang Yiqing et al. reviewed the research progress of lactic acid and lactation modification in cardiovascular diseases in the *Chinese Journal of Arteriosclerosis* (Vol. 33, No. 8, 2025, pp. 645-654). However, currently, there are almost no commercially available technologies for the in vitro synthesis of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid molecules. Therefore, the artificial synthesis of this lysine lactylated product is essential for exploring this field. Based on its aforementioned characteristics, 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid has a potential market in the pharmaceutical and chemical industries.

[0005] CN120172912A reports a method for preparing dual-labeled diagnostic molecules by reacting lysine with activated esters (such as acridine sulfonamide-NHS) under alkaline conditions. However, this method uses expensive activated ester raw materials, requires the introduction of an inorganic base into the reaction system, and the products are specifically designed for chemiluminescence detection with complex molecular structures. In contrast, developing a method to synthesize small molecules with nutritional and health-promoting functions by reacting inexpensive and readily available common esters (such as methyl lactate) with amino acids under milder and simpler conditions is of great significance and has broad market prospects. Summary of the Invention

[0006] The purpose of this invention is to provide 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its applications. This invention represents the first successful direct acylation reaction of methyl lactate and lysine at room temperature, synthesizing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid in a one-step reaction. This method is energy-efficient, has a short process, and is more suitable for the preparation of heat-sensitive compounds and green industrial production. The resulting product contains both methyl lactate and lysine structures, making it a key product for histone lysine lactylation modification. It can be used in the treatment of cardiovascular diseases and as a green chemical intermediate, showing broad prospects for pharmaceutical and industrial applications.

[0007] To achieve the above objective, the present invention provides a method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, comprising the following steps:

[0008] S1. Place methyl lactate and lysine in a reaction vessel and stir to react;

[0009] S2. After the reaction is complete, the mixture obtained from the reaction is subjected to solid-liquid centrifugation.

[0010] S3. After purifying the separated solid, a milky white solid 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid is obtained.

[0011] Preferably, in S1, the mass ratio of methyl lactate to lysine is (5-15):1.

[0012] Preferably, in S1, the stirring speed is 200-300 rpm, the reaction time is 0.5-12 h, and the reaction temperature is 15-35℃.

[0013] Preferably, the specific operation of solid-liquid separation in S2 is as follows: the mixture obtained from the reaction is transferred to a centrifuge bottle and solid-liquid separation is carried out by high-speed centrifugation.

[0014] Preferably, in S2, the centrifugation speed is 4000-9000 rpm and the centrifugation time is 10-30 min.

[0015] Preferably, in S3, the specific operation for purifying the separated solid is as follows: the separated solid is washed with solvent by stirring, centrifuged at high speed, and the lower layer of solid is taken off. The washing and centrifugation process is repeated three times and then dried to obtain the milky white product 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0016] Preferably, in S3, the solvent is ethyl acetate, the amount of ethyl acetate is 60-80 mL, the high-speed centrifugation speed is 3000-7000 rpm, and the drying temperature is 30-40℃.

[0017] The present invention also provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, which is prepared by the above-described method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid. The prepared 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid contains a methyl lactate structure and a lysine structure.

[0018] Preferably, the structural formula of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid is:

[0019]

[0020] This invention also provides an application of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid in the pharmaceutical and chemical fields.

[0021] The amidation reaction between esters and acids often requires heating to facilitate the reaction. Heating not only provides energy to overcome the activation energy but also increases the reaction rate. Without heating to assist the reaction, it may be difficult for the reaction to occur or the reaction rate may be extremely slow, often requiring several days. The reaction of this invention does not require heating and has a fast reaction rate, achieving efficient conversion in 0.5-12 hours at room temperature.

[0022] Therefore, the present invention employs the above-mentioned 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application, which have the following beneficial effects:

[0023] (1) Using methyl lactate and lysine as raw materials, 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid can be obtained in one step at room temperature of 15-35℃ without heating, catalyst or organic base. Mild conditions can also prevent lysine from racemizing and degrading.

[0024] (2) 2-Amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, as a lactylated product of lysine in histones, was synthesized in vitro at room temperature for the first time. It can also play an important role in the treatment of cardiovascular diseases and has great potential application value.

[0025] (3) The technology of this invention is green and environmentally friendly, low cost, low energy consumption, and more suitable for the preparation of heat-sensitive compounds and green industrial production.

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0027] Figure 1 This is a physical image of the product obtained in Example 1 of the present invention, which describes a 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application.

[0028] Figure 2 This is a high-resolution analytical spectrum of the product obtained in Example 1 of the present invention, which describes a 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application.

[0029] Figure 3 This is an infrared spectrum of the reaction raw materials and the obtained product in Example 1 of the present invention, which describes a 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application.

[0030] Figure 4 This is a hydrogen nuclear magnetic resonance spectrum of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and the product obtained in Example 1 of this invention;

[0031] Figure 5 This is the carbon NMR spectrum of a product obtained from Example 1 of the present invention, namely, 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application. Detailed Implementation

[0032] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0034] In this invention, unless otherwise specified, all other test materials and instruments are conventional test materials in the field and can be purchased through commercial channels.

[0035] Example 1

[0036] This invention provides a 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the structural formula of which is:

[0037] The prepared 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid contains a methyl lactate structure and a lysine structure. Its preparation method includes the following steps:

[0038] (1) Add 60g of methyl lactate and 10g of lysine to a 100mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 30℃ for 6h. After the reaction is complete, transfer the mixture to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (4000rpm, 25min).

[0039] (2) The solid product obtained from the solid-liquid separation in step (1) was thoroughly washed with 30 mL of ethyl acetate, and then centrifuged to obtain the washed solid product; the washed solid product was further washed with 60 mL of ethyl acetate (divided into two portions of 30 mL each), centrifuged, and then dried in an oven at 35 °C to obtain 12.6 g of milky white solid (e.g. Figure 1 (As shown).

[0040] (3) The white solid is readily soluble in water. When the aqueous solution is diluted to 1 ppm and analyzed by high-resolution liquid chromatography-mass spectrometry, only one major product peak is found, and the molecular weight of the product is 218 (recommended molecular formula is C9H). 18 N2O4)(as Figure 2 As shown, Figure 2 (a) in the figure is a chromatogram. Figure 2 (b) is the mass spectrum), which was further analyzed by infrared spectroscopy comparison (infrared spectral analysis of the reactants and the resulting products, such as...). Figure 3 As shown in the figure, the product obtained from the reaction showed a peak with a newly added amide functional group (3308 cm⁻¹). -1 1644cm -1 ); after analyzing the proton nuclear magnetic resonance spectrum (e.g. Figure 4 (as shown) and carbon spectroscopy analysis (such as) Figure 5 Analysis of the sample (as shown) revealed the presence of functional groups including carboxyl, hydroxyl, peptide bonds, methyl, and amino groups. Based on the structural characteristics of the reactants methyl lactate and lysine, and combined with high-resolution liquid chromatography-mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance analysis, the product was identified as 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0041] Example 2

[0042] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0043] (1) Add 20g of methyl lactate and 4g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 25℃ for 10h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (5000rpm, 20min).

[0044] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 5.6 g of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0045] Example 3

[0046] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0047] (1) Add 30g of methyl lactate and 3g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 35℃ for 3h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (6000rpm, 15min).

[0048] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 4.5 g of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0049] Example 4

[0050] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0051] (1) Add 30g of methyl lactate and 6g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 20℃ for 12h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (5500rpm, 22min).

[0052] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 8 g of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0053] Example 5

[0054] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0055] (1) Add 16g of methyl lactate and 2g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 15℃ for 6h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (7500rpm, 12min).

[0056] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0057] Example 6

[0058] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0059] (1) Add 18g of methyl lactate and 3g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 23℃ for 7h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (8500rpm, 10min).

[0060] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0061] Example 7

[0062] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0063] (1) Add 15g of methyl lactate and 5g of lysine to a 50mL reactor, control the mechanical stirring speed to 250rpm, and keep the reactor temperature at 32℃ for 1h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (9000rpm, 10min).

[0064] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0065] Example 8

[0066] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0067] (1) Add 21g of methyl lactate and 3g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 18℃ for 9h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (4500rpm, 30min).

[0068] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0069] Example 9

[0070] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0071] (1) Add 27g of methyl lactate and 3g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 27℃ for 8h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (7000rpm, 18min).

[0072] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0073] Example 10

[0074] This invention provides 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, the preparation method of which includes the following steps:

[0075] (1) Add 21g of methyl lactate and 4g of lysine to a 50mL reactor, control the mechanical stirring speed at 250rpm, and keep the reactor temperature at 17℃ for 4h. After the reaction is complete, transfer the product to a centrifuge bottle and separate the solid and liquid by high-speed centrifugation (8000rpm, 21min).

[0076] (2) The solid product obtained in step (1) was thoroughly washed with 20 mL of ethyl acetate and then centrifuged to obtain the washed solid product. The washed solid product was further washed with 40 mL of ethyl acetate (divided into two portions of 20 mL each time), centrifuged, and then dried in an oven at 35 °C to obtain 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

[0077] Therefore, this invention utilizes the aforementioned 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, its preparation method, and its application to achieve for the first time the direct acylation reaction of methyl lactate and lysine at room temperature. This one-step synthesis of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid is energy-efficient, has a short process, and is more suitable for the preparation of heat-sensitive compounds and green industrial production. The resulting product contains both methyl lactate and lysine structures, making it a key product for histone lysine lactylation modification. It can be used in the treatment of cardiovascular diseases and as a green chemical intermediate, showing broad prospects for pharmaceutical and industrial applications.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, characterized in that: Includes the following steps: S1. Place methyl lactate and lysine in a reaction vessel, stir, and react at 15-35℃; S2. After the reaction is complete, the mixture obtained from the reaction is subjected to solid-liquid centrifugation. S3. After purifying the separated solid, a milky white solid 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid is obtained.

2. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 1, characterized in that: In S1, the mass ratio of methyl lactate to lysine is (5-15):

1.

3. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 1, characterized in that: In S1, the stirring speed is 200-300 rpm and the reaction time is 0.5-12 h.

4. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 1, characterized in that: The specific operation for solid-liquid separation in S2 is as follows: the mixture obtained from the reaction is transferred to a centrifuge bottle and solid-liquid separation is carried out by high-speed centrifugation.

5. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 4, characterized in that: In S2, the centrifugation speed is 4000-9000 rpm and the centrifugation time is 10-30 min.

6. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 1, characterized in that: In S3, the specific operation for purifying the separated solid is as follows: the separated solid is stirred and washed with solvent, centrifuged at high speed, and the lower layer of solid is taken off. The washing and centrifugation process is repeated three times and then dried to obtain the milky white product 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid.

7. The method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 6, characterized in that: In S3, the solvent is ethyl acetate, the amount of ethyl acetate used is 60-80 mL, the high-speed centrifugation speed is 3000-7000 rpm, and the drying temperature is 30-40℃.

8. A 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid, characterized in that: It was prepared by the method for preparing 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to any one of claims 1-7.

9. The 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid according to claim 8, characterized in that: The structural formula of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid is:

10. The application of 2-amino-6-[(2-hydroxypropionyl)amino]hexanoic acid as described in any one of claims 8-9 in the pharmaceutical and chemical fields.

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