Preparation method of second-generation denitrified flavin TND1128

Abstract

The invention discloses a preparation method of second-generation denitrified flavin TND1128, which comprises the following steps: S1, by taking 1-methylbarbituric acid and o-aminobenzaldehyde as raw materials and a mixture of water and alcohol as a solvent, heating and reacting to generate an intermediate I; s2, taking the intermediate I as a raw material, and performing ethylation under the combined action of inorganic alkali and an ethylation reagent to generate a TND1128 crude product; s3, the TND1128 crude product is purified, and a TND1128 pure product is obtained; according to the invention, 1-methylbarbituric acid and 2-nitrobenzaldehyde are taken as raw materials for cyclization synthesis of an intermediate I, then ethylation and pulping purification are carried out under the combined action of inorganic base and an ethylation reagent, and high-purity TND1128 is synthesized in a high-yield, high-specificity and high-selectivity manner; the method has the advantages of simple process route, good reaction selectivity, high yield, cheap and easily available raw materials, low equipment requirement, easy realization of industrial production and the like.

Description

Technical Field

[0001] This invention relates to the field of organic chemical synthesis technology, and in particular to a method for preparing second-generation denitrifying flavin TND1128. Background Technology

[0002] With the rapid aging of the population worldwide, neurodegenerative diseases such as Alzheimer's, Parkinson's, and stroke are becoming increasingly prevalent, posing a pressing social problem that society urgently needs to address. One of the main causes of these diseases is the disruption of mitochondrial function. TND1128 (CAS No.: 59997-14-7) is a substance similar to NAD+ (nicotinamide adenine dinucleotide), possessing the same redox function as NAD+. Its anti-aging and other biological activities are dozens of times stronger than desoxyflavin, and it exhibits better stability. As a promising next-generation anti-aging health product, it can activate mitochondria and sirtuin genes, thus delaying aging and preventing the aforementioned neurodegenerative diseases. Simultaneously, TND1128 also enhances immunity, maintains eye health, and protects the skin and oral mucosa. Currently, there are few publicly disclosed preparation methods for TND1128, necessitating the development of new synthetic routes that are simple to operate and have high yields. Summary of the Invention

[0003] The technical problem to be solved by this invention is to provide a method for preparing second-generation denitrifying flavin TND1128, addressing the shortcomings of the prior art. This invention uses 1-methylbarbituric acid and o-aminobenzaldehyde as raw materials to cyclize intermediate I, followed by ethylation and pulping purification in three steps under the combined action of an inorganic base and an ethylating reagent, to synthesize high-purity TND1128 with high yield, high specificity, and selectivity.

[0004] To achieve the above objectives, the technical solution adopted by this invention is: a method for preparing second-generation denitrifying flavin TND1128, comprising the following steps:

[0005] S1. Using 1-methylbarbituric acid and o-aminobenzaldehyde as raw materials, and a mixture of water and alcohol as solvent, the reaction is heated to generate intermediate I;

[0006] S2. Using intermediate I as raw material, TND1128 crude product is generated by ethylation under the combined action of inorganic base and ethylating agent.

[0007] S3 and crude TND1128 were purified to obtain pure TND1128.

[0008] The preparation route is shown below:

[0009]

[0010] Preferably, the molar ratio of 1-methylbarbituric acid to o-aminobenzaldehyde in step S1 is 1 to 1.4:1, for example, the molar ratio is 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or any value formed by any two of them; more preferably, the ratio is 1.1:1.

[0011] Preferably, the volume ratio of water to alcohol is 1:3 to 3:1; for example, the volume ratio is 3:1, 2:1, 1:1, 1:2, 1:3 or any combination thereof; more preferably, the ratio is 1:1 in order to maintain good solubility of both 1-methylbarbituric acid and o-aminobenzaldehyde.

[0012] The total volume of the solvent used in step S1, expressed in mL and g, is in a mass ratio of 10 to 30:1 to o-aminobenzaldehyde. For example, the ratio can be 30, 25, 20, 15, 10, or any combination thereof; more preferably, the ratio is 20 to ensure thorough mixing of the raw material reaction system.

[0013] Preferably, the alcohol used in step S1 is at least one of methanol, ethanol, n-propanol, isopropanol, and n-butanol; more preferably, the alcohol used is ethanol.

[0014] Preferably, the reaction temperature in step S1 is 65 to 90°C, for example, 65, 70, 75, 80, 85, 90°C or any combination thereof; more preferably, the reaction temperature is 75°C, in order to ensure that the reaction proceeds quickly and reduce the occurrence of side reactions.

[0015] The reaction time in step S1 is 2 to 6 hours, for example, 2, 3, 4, 5, 6 hours or any combination thereof. The endpoint of the reaction is confirmed by TLC or HPLC to indicate that the o-aminobenzaldehyde has completely reacted.

[0016] Preferably, after the reaction is complete, step S1 further includes:

[0017] The reaction solution was cooled to room temperature, filtered, the filter cake was washed with water, the filter cake was recovered, and dried to obtain intermediate I.

[0018] Preferably, step S2 includes: mixing intermediate I and an organic solvent, adding an inorganic base in batches, stirring, adding an ethylating agent dropwise, heating to a certain temperature to react until intermediate I reacts completely, and obtaining crude TND1128.

[0019] Preferably, the ratio of the volume of the organic solvent to the mass of intermediate I in step S2 is 4 to 10:1, in volume units of mL and weight units of g; for example, the ratio is 4, 5, 6, 7, 8, 9, 10 or any value formed by any two of them, more preferably, the ratio is 6.

[0020] In step S2, the molar ratio of the inorganic base to intermediate I is 1.1 to 2.2:1, for example, the molar ratio is 1.1:1, 1.2:1, 1.5:1, 2.0:1, 2.2:1 or any value formed by any two of them, more preferably, the ratio is 1.5:1.

[0021] The molar ratio of the ethylating agent to intermediate I is 1.1 to 1.5:1, for example, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1 or any value formed by any two of them, more preferably, the ratio is 1.2:1.

[0022] Preferably, in step S2, the inorganic base is at least one of sodium carbonate, potassium carbonate, cesium carbonate, potassium tert-butoxide, sodium tert-butoxide, and sodium hydrogen hydride; more preferably, the inorganic base is any one of sodium carbonate, potassium carbonate, and potassium tert-butoxide.

[0023] Preferably, the ethylating agent is at least one of diethyl sulfate, iodoethane, ethyl p-toluenesulfonate, and bromoethane; more preferably, the ethylating agent is any one of diethyl sulfate, iodoethane, and bromoethane.

[0024] Preferably, the organic solvent is at least one of acetone, acetonitrile, tetrahydrofuran, methyltetrahydrofuran, DMF (N,N-dimethylformamide), and DMAc (N,N-dimethylacetamide); more preferably, the organic solvent is any one of acetone, tetrahydrofuran, and DMF.

[0025] Preferably, the reaction temperature in step S2 is 20, 40, 60, 80, or any value formed by any two of them; more preferably, the reaction temperature is 60°C.

[0026] Preferably, the reaction time in step S2 is 4, 6, 8, 10, 12 hours or any combination thereof, and the endpoint of the reaction is confirmed by TLC (thin-layer chromatography) or HPLC (high-performance liquid chromatography) as the standard for the complete reaction of intermediate I.

[0027] Preferably, after the reaction is complete, step S2 further includes:

[0028] The reaction solution was quenched with water, stirred, filtered, the filter cake was rinsed with water, collected, and dried to obtain crude TND1128.

[0029] Preferably, step S3 includes: mixing crude TND1128 with acetic acid, heating to a certain temperature and stirring for a period of time, cooling to room temperature, filtering, washing the filter cake, and drying to obtain pure TND1128.

[0030] Preferably, the ratio of the volume of acetic acid to the mass of TND1128 in step S3 is 4 to 10:1, in volume units of mL and weight units of g. For example, the ratio is 4, 6, 8, 10 or any value formed by any two of them. More preferably, the ratio is 6 to ensure sufficient stirring.

[0031] Preferably, the heating and stirring temperature in step S3 is 60, 70, 80, 90, 100°C or any value between any two of them, more preferably 80°C.

[0032] Preferably, the heating and stirring time in step S3 is 1, 2, 3, 4, 5 hours or any value formed by any two of them, more preferably 3 hours.

[0033] Preferably, the preparation method of the second-generation denitrifying flavin TND1128 includes the following steps:

[0034] S1. Add 1-methylbarbituric acid and o-aminobenzaldehyde to a mixture of ethanol and water, react at 65-90°C for 2-6 hours, cool to room temperature, filter, wash the filter cake, and dry to obtain intermediate I.

[0035] S2. Mix intermediate I with organic solvent, add inorganic base in batches, stir for 15-60 min, add ethylation reagent dropwise at room temperature, react at 20-80℃ for 4-12 h, quench with water, stir and filter, wash filter cake, dry to obtain crude TND1128.

[0036] The inorganic base is any one of sodium carbonate, potassium carbonate, and potassium tert-butoxide; the ethylating reagent is any one of diethyl sulfate, iodoethane, and bromoethane; and the organic solvent is any one of acetone, tetrahydrofuran, and DMF.

[0037] S3. Mix crude TND1128 with acetic acid, heat to 60-100℃ and stir for 1-5 hours, cool to room temperature, filter, wash the filter cake, and dry to obtain pure TND1128.

[0038] The beneficial effects of this invention are:

[0039] This invention uses 1-methylbarbituric acid and 2-nitrobenzaldehyde as raw materials to cyclize intermediate I, and then ethylates and purifies it in three steps under the combined action of inorganic base and ethylating reagent, to synthesize high-purity TND1128 with high yield, high specificity and selectivity. This method has the advantages of simple process route, good reaction selectivity, high yield, cheap and readily available raw materials, low equipment requirements and easy to realize industrial production. Attached Figure Description

[0040] Figure 1 The 1H NMR spectrum is shown for the pure TND1128 prepared in Example 1. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0042] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0043] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples are commercially available. For examples where specific conditions are not specified, conventional conditions or conditions recommended by the manufacturer are followed. For reagents or instruments whose manufacturers are not specified, they are all commercially available products.

[0044] Example 1:

[0045] A method for preparing second-generation denitrifying flavin TND1128 includes the following steps:

[0046] S1. In a 2L three-necked flask, add 50g (413mmol, 1.0eq) of o-aminobenzaldehyde, 64.52g (454mmol, 1.1eq) of 1-methylbarbituric acid, 500mL of water and 500mL of ethanol, and then slowly heat to 75℃ and react for 3h. After the reaction of o-aminobenzaldehyde is complete by TLC, the reaction solution is cooled to room temperature, filtered, and the filter cake is washed with water and ethanol successively. The filter cake is collected, dried, and 87.46g of yellowish-brown solid intermediate I is obtained, with a yield of 93.2%.

[0047] S2. In a 2L three-necked flask, add 87.46g (385mmol, 1.0eq) of intermediate I and 525mL of DMF, then add 79.7g (578mmol, 1.5eq) of potassium carbonate in portions. After stirring for 30min, add 71.2g (462mmol, 1.2eq) of diethyl sulfate dropwise, and then heat to 70℃ and react for 4h. When the TLC intermediate I is completely reacted, 1050mL of water is added to quench the reaction solution, and after stirring for 30min, filter. Wash the filter cake with water, collect and dry it to obtain 89.9g of crude TND1128, with a yield of 91.5%.

[0048] S3. Add 89.9g of crude TND1128 and 540mL of acetic acid to a 1L three-necked flask, heat to 80℃ and stir for 3h; then cool to room temperature, filter, wash the filter cake with acetic acid, collect the filter cake, and dry to obtain 85.6g of pure TND1128 in a bright yellow solid, with a yield of 95.2%.

[0049] The H NMR spectrum of the pure TND1128 prepared in this embodiment is as follows: Figure 1 As shown, the H NMR data are as follows:

[0050] 1 H NMR (400MHz, CDCl3): δ8.90(s,1H),7.94(dd,J=8.0,1.5Hz,1H),7.90(ddd,J=8.7,7.1,1.6Hz,1H ),7.72(d,J=8.8Hz,1H),7.50(t,J=7.5Hz,1H),4.87(s,2H),3.48(s,3H),1.49(t,J=7.1Hz,3H).

[0051] Example 2:

[0052] A method for preparing second-generation denitrifying flavin TND1128 includes the following steps:

[0053] S1. In a 2L three-necked flask, add 50g (413mmol, 1.0eq) of o-aminobenzaldehyde, 58.65g (413mmol, 1.0eq) of 1-methylbarbituric acid, 400mL of water and 600mL of ethanol, and then slowly heat to 70℃ and react for 3.5h. After the reaction of o-aminobenzaldehyde is complete by TLC, the reaction solution is cooled to room temperature, filtered, and the filter cake is washed with water and ethanol successively. The filter cake is collected, dried, and 86.9g of yellowish-brown solid intermediate I is obtained, with a yield of 92.6%.

[0054] S2. In a 2L three-necked flask, add 86.9g (382mmol, 1.0eq) of intermediate I and 695mL of acetone, then add 73.0g (688mmol, 1.8eq) of sodium carbonate in portions. After stirring for 30min, add 65.5g (420mmol, 1.1eq) of iodoethane dropwise, and then heat to 50℃ for 6h. When the reaction of TLC intermediate I is complete, quench the reaction solution with 1390mL of water, stir for 30min, filter, wash the filter cake with water, collect and dry to obtain 87.2g of crude TND1128, with a yield of 89.3%.

[0055] S3. Add 87.2g of crude TND1128 and 436mL of acetic acid to a 1L three-necked flask, heat to 70℃ and stir for 4h; then cool to room temperature, filter, wash the filter cake with acetic acid, collect the filter cake, and dry to obtain 83.5g of pure TND1128 in a bright yellow solid, with a yield of 95.7%.

[0056] Example 3:

[0057] A method for preparing second-generation denitrifying flavin TND1128 includes the following steps:

[0058] S1. In a 2L three-necked flask, add 50g (413mmol, 1.0eq) of o-aminobenzaldehyde, 70.43g (496mmol, 1.2eq) of 1-methylbarbituric acid, 700mL of water and 500mL of ethanol, and then slowly heat to 80℃ and react for 2.5h. After the reaction of o-aminobenzaldehyde is complete by TLC, the reaction solution is cooled to room temperature, filtered, and the filter cake is washed with water and ethanol successively. The filter cake is collected, dried, and 87.2g of yellowish-brown solid intermediate I is obtained, with a yield of 93.0%.

[0059] S2. In a 2L three-necked flask, add 87.2g (384mmol, 1.0eq) of intermediate I and 436mL of tetrahydrofuran, then add 51.7g (461mmol, 1.2eq) of potassium tert-butoxide in portions. After stirring for 30min, add 71.2g (462mmol, 1.1eq) of bromoethane dropwise, and continue the reaction at room temperature for 4h. When intermediate I of TLC is completely reacted, 872mL of water is added to quench the reaction solution, and after stirring for 30min, filter. Wash the filter cake with water, collect and dry it to obtain 89.1g of crude TND1128, with a yield of 90.9%.

[0060] S3. Add 89.1g of crude TND1128 and 624mL of acetic acid to a 1L three-necked flask, heat to 90℃ and stir for 2h; then cool to room temperature, filter, wash the filter cake with acetic acid, collect the filter cake, and dry to obtain 84.3g of pure TND1128 in a bright yellow solid, with a yield of 94.6%.

[0061] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details.

Claims

1. A method for preparing second-generation denitrifying flavin TND1128, characterized in that, Includes the following steps: S1. Using 1-methylbarbituric acid and o-aminobenzaldehyde as raw materials, and a mixture of water and alcohol as solvent, the reaction is heated to generate intermediate I; S2. Using intermediate I as raw material, TND1128 crude product is generated by ethylation under the combined action of inorganic base and ethylating agent. S3 and crude TND1128 were purified to obtain pure TND1128. The preparation route is shown below:

2. The preparation method of the second-generation denitrifying flavin TND1128 according to claim 1, characterized in that, In step S1, the molar ratio of 1-methylbarbituric acid to o-aminobenzaldehyde is 1 to 1.4:1, and the volume ratio of water to alcohol is 1 to 3:

1. The ratio of the total volume of the solvent used in step S1 to the mass of o-aminobenzaldehyde is 10 to 30:1, measured in mL and g respectively.

3. The preparation method of second-generation denitrifying flavin TND1128 according to claim 2, characterized in that, The alcohol used in step S1 is at least one of methanol, ethanol, n-propanol, isopropanol, and n-butanol.

4. The preparation method of the second-generation denitrifying flavin TND1128 according to claim 3, characterized in that, In step S1, the reaction temperature is 65–90℃ and the reaction time is 2–6 hours.

5. The preparation method of the second-generation denitrifying flavin TND1128 according to claim 1, characterized in that, Step S2 includes: mixing intermediate I and an organic solvent, adding an inorganic base in batches, stirring, adding an ethylating agent dropwise, and reacting at 20–80°C for 4–12 h to obtain crude TND1128.

6. The preparation method of the second-generation denitrifying flavin TND1128 according to claim 5, characterized in that, The ratio of the volume of the organic solvent to the mass of intermediate I in step S2 is 4 to 10:1, measured in mL and g respectively. In step S2, the molar ratio of inorganic base to intermediate I is 1.1 to 2.2:1, and the molar ratio of ethylating agent to intermediate I is 1.1 to 1.5:

1.

7. The preparation method of second-generation denitrifying flavin TND1128 according to claim 6, characterized in that, In step S2, the inorganic base is at least one of sodium carbonate, potassium carbonate, cesium carbonate, potassium tert-butoxide, sodium tert-butoxide, and sodium hydrogen hydride; the ethylating agent is at least one of diethyl sulfate, iodoethane, ethyl p-toluenesulfonate, and bromoethane; and the organic solvent is at least one of acetone, acetonitrile, tetrahydrofuran, methyltetrahydrofuran, DMF (N,N-dimethylformamide), and DMAc (N,N-dimethylacetamide).

8. The method for preparing second-generation denitrifying flavin TND1128 according to claim 1, characterized in that, Step S3 includes: mixing crude TND1128 with acetic acid, heating to 60-100℃ and stirring for 1-5 hours, cooling to room temperature, filtering, washing the filter cake, and drying to obtain pure TND1128.

9. The method for preparing second-generation denitrifying flavin TND1128 according to claim 8, characterized in that, In terms of volume (mL) and weight (g), the ratio of acetic acid volume to TND1128 mass in step S3 is 4–10:

1.

10. The method for preparing second-generation denitrifying flavin TND1128 according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Add 1-methylbarbituric acid and o-aminobenzaldehyde to a mixture of ethanol and water, react at 65-90°C for 2-6 hours, cool to room temperature, filter, wash the filter cake, and dry to obtain intermediate I. S2. Mix intermediate I with organic solvent, add inorganic base in batches, stir for 15-60 min, add ethylation reagent dropwise at room temperature, react at 20-80℃ for 4-12 h, quench with water, stir and filter, wash filter cake, dry to obtain crude TND1128. The inorganic base is any one of sodium carbonate, potassium carbonate, and potassium tert-butoxide; the ethylating reagent is any one of diethyl sulfate, iodoethane, and bromoethane; and the organic solvent is any one of acetone, tetrahydrofuran, and DMF. S3. Mix crude TND1128 with acetic acid, heat to 60-100℃ and stir for 1-5 hours, cool to room temperature, filter, wash the filter cake, and dry to obtain pure TND1128.

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