WO2021092919A1 - Nicotinamide mononucleotide intermediate and method for synthesizing nicotinamide mononucleotide - Google Patents

Abstract

Disclosed are a nicotinamide mononucleotide intermediate and a method for synthesizing nicotinamide mononucleotide, and the present invention belongs to the field of chemical synthesis. Provided is a method for synthesizing a nicotinamide mononucleotide intermediate as represented by formula III, wherein the nicotinamide mononucleotide intermediate is obtained by reacting compounds I and II under the action of a Lewis acid. Further provided is a method for preparing nicotinamide mononucleotide, the method involving: first synthesizing nicotinamide mononucleotide intermediate III, then removing a protection group, and then performing phosphorylation. The synthesis method has the advantages of a high stereoselectivity, a low cost and being environmentally friendly.

Description

Nicotinamide mononucleotide intermediate and synthesis method of nicotinamide mononucleotide Technical field

The invention relates to a nicotinamide mononucleotide intermediate and a method for synthesizing nicotinamide mononucleotide, and belongs to the field of chemical synthesis.

Background technique

Nicotinamide mononucleotide (β-NMN) is the ^{precursor of nicotinamide adenine dinucleotide (NAD +} ). NAD ⁺ helps cell metabolism, mitochondrial function and energy production, and β-NMN stimulates cell DNA repair. Therefore, β-NMN has the effect of exercise recovery and restoring the vitality of muscle tissue and other cells. In view of the important potential of β-NMN as a dietary supplement to bring health benefits, it is necessary to develop an efficient and large-scale production of β-NMN preparation process.

Currently, β-NMN is mainly prepared by three methods: 1. Ethyl nicotinate is used as a synthetic raw material (see: Tianle Yang, Noel Yan-Ki Chan, and Anthony A. Sauve. Synthesis of Nicotinamide Riboside and Derivatives: Effective Agents for Increasing Nicotinamide Adenine Dinucleotide Concentrations in Mammalian Cells. J. Med. Chem. 2007, 50, 6458-6461); 2. Using halogen-substituted tetraacetylated ribose as the synthetic raw material (see: Jaemoon Lee, Hywyn Chuurchil, Woo-Baeg Choi, Joseph E, Lynch, F, e. Roberts, RPVolante and Paul J. Reider. A chemical synthesis of nicotinamide adenine dinucleotide (NAD+). Chem. Commun., 1999, 729-730); 3. Tetraacetylated ribose Nicotinamide and disilylated nicotinamide are prepared by glycosylation reaction (see: Palmaris Franchetti, Michela Pasqualini, Riccardo Petrelli, Massimo Ricciutelli, Patrizia Vita and Loredana Cappellacci. Stereoselective Synthesis and Biopharmaceutical Chemicalside Medicine and Biopharmaceutical Analysis & Biopharmaceutical Analysis .2004, 14(18): 4655-4658).

The raw material ethyl nicotinate used in the first method mentioned above cannot meet the market demand commercially, and the price is very expensive. The main disadvantage of the second method is the poor selectivity of the glycosylation step (β-isomer vs α-isomer), which leads to indispensable subsequent purification operations and difficulties in scale-up production. The synthesis raw materials of the third method are easily available, the price is relatively low, and the stereoselectivity of the reaction is better. Compared with the other two preparation methods, it has obvious advantages; however, the synthesis process requires a large excess of silyl groups. Chemical reagents (such as TMSCl) and glycosylation reagents (TMSOTf), resulting in the ineffective reduction of production costs.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. For this reason, the purpose of the present invention is to provide a method for synthesizing nicotinamide mononucleotide intermediates. Another object of the present invention is to provide a method for preparing nicotinamide mononucleotide.

The present invention provides a method for synthesizing a nicotinamide mononucleotide intermediate represented by formula III: Compound I and II are reacted under the action of Lewis acid to obtain;

Wherein, R ₁ , R ₂ , and R _{3 are} independently selected from acetyl or benzoyl.

Further, the Lewis acid is selected from at least one of TMSOTf, ZnCl ₂ , TiCl ₄ , Ti(OiPr) ₂ , AlCl ₃ , SnCl ₂ , and BF ₃ .

Further, the feeding amount of compound II is 1 eq., and the feeding amount of TMSOTf is 0.5 to 2.5 eq.

Preferably, the feeding amount of compound II is 1 eq., and the feeding amount of TMSOTf is 1.6 eq.

Further, the reaction solvent is selected from at least one of dichloromethane, dichloroethane, and acetonitrile.

Further, the reaction is carried out under a protective atmosphere.

Preferably, the protective atmosphere is a nitrogen atmosphere.

Further, the reaction temperature is 0-10°C.

Further, the feeding amount of compound II is 1 eq., and the feeding amount of compound I is 1.0-1.1 eq.

Further, compound II is prepared by the following method: the raw material SM-1 reacts with the silylation reagent to obtain:

Further, the feeding amount of the raw material SM-1 is 1 eq., and the feeding amount of the silylation reagent is 1.2 eq.

Further, the silylation reagent is selected from at least one of TMSF, TMSCl, TMSBr, TMSI, and TMSOTf.

Further, the reaction solvent is hexamethyldisilazane.

Further, the reaction temperature is 100 to 150°C.

The present invention provides a preparation method of nicotinamide mononucleotide, which comprises the following steps:

a. Obtain Intermediate Ⅲ according to the synthetic method as described above;

b. Intermediate III removes the protective group to obtain Intermediate IV:

c. Phosphorylation of intermediate IV to obtain nicotinamide mononucleotide:

Further, in step b, the intermediate III is placed in a base alcohol solution to react to remove the protective group.

Further, the base is selected from at least one of NH ₃ , triethylamine, diisopropylethylamine, NaOH, LiOH, KOH, NaOEt, and KOEt.

Further, the alcohol is selected from at least one of ^{MeOH, EtOH, n} PrOH, ⁱ PrOH, ⁿ BuOH, ⁱ BuOH, and ^{t BuOH.}

Further, the reaction temperature in step b is -10 to 0°C.

Further, step c uses at least one of the following phosphorylation reagents: POCl ₃ , POCl(OEt) ₂ , POCl(OMe) ₂ , POCl(OBn) ₂ .

Further, the reaction solvent in step c is selected from at least one of _{PO(OEt) 3} , PO(OMe) _{3 and MeCN.}

Further, the reaction temperature in step c is -10 to 0°C.

In the present invention, the abbreviation TMSOTf stands for trimethylsilyl trifluoromethanesulfonate; TMSF stands for trimethylfluorosilane; TMSCl stands for trimethylchlorosilane; TMSBr stands for trimethylbromosilane; TMSI stands for trimethylsilyl iodide .

The present invention provides a method for synthesizing nicotinamide mononucleotide intermediate, and further provides a method for preparing nicotinamide mononucleotide based on this. Compared with the prior art, the synthesis method of the present invention mainly has the following advantages:

1. The present invention creatively uses monosilylated nicotinamide as the raw material for the glycosylation reaction. Compared with the prior art method using disilylated nicotinamide, the amount of silylation reagent is reduced by half, and at the same time it can Ensure the stereoselectivity of the glycosylation reaction, and obtain the β-isomer with a high degree of stereoselectivity.

2. The reaction of ribose and monosilylated nicotinamide only requires a catalytic amount of glycosylation reagent. Taking TMSOTf as an example, the dosage of 0.5 to 2.5 eq. can complete the reaction. Compared with direct glycosylation of nicotinamide or disilylated nicotinamide glycosylation, 5 to 8 eq. is required. The amount of reagent is obtained. Significantly reduced (see: Shinji Tanimori, Takeshi Ohta and Misunori Kirihata. An Efficient Chemical Synthesis of Nicotinaminde Riboside (NAR) and Analogues. Bioorganic & Medicinal Chemistry Letters 12 (2002) 1135-1137).

3. The synthesis method of the present invention is convenient and efficient, does not require HPLC purification treatment, has less sewage discharge, and is more environmentally friendly.

Detailed ways

The solution of the present invention will be explained below in conjunction with examples. Those skilled in the art will understand that the following embodiments are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the examples, it shall be carried out in accordance with the techniques or conditions described in the literature in the field or in accordance with the product specification. The reagents or instruments used without the manufacturer's indication are all conventional products that can be purchased on the market.

Example 1 Preparation of nicotinamide mononucleotide using the method of the present invention

The synthetic route is as follows:

Step 1: Preparation of monosilylated nicotinamide 2

Prepare a clean, dry, 500 mL autoclave reactor filled with magnetic particles. Nicotinamide (50g, 0.41mol, 1.0eq) was added at 20～30℃, followed by HMDS (150mL) and TMSCl (53.4g, 0.49mol, 1.2eq.), the reaction temperature was raised to 100～150℃ and stirred for 16h. Then the reactants were transferred to a single-necked flask, and the remaining reactants in the reactor were transferred to a 1L single-necked flask with 50 mL of HMDS. The reactants were combined and distilled at 60-70°C under high vacuum conditions until no more distillate was observed to obtain 70 g of light yellow solid with a yield of 82% and an HPLC purity of 99%.

Step 2: Preparation of compound 4

Prepare a clean and dry 500mL four-neck round bottom flask (RBF), equipped with a mechanical stirrer, thermometer and dropping funnel. Under the protection of nitrogen, add 150 mL of dichloroethane (DCE) at 20-30°C, and then cool the clear solution to 0-10°C. Under the protection of nitrogen, TMSOTf (74.5mL, 0.41mol, 1.6eq) was added at 0～10℃. Then slowly add 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose (compound 3,90g, 0.28mol, 1.1eq) dissolved in 150mL DCE solution and compound 2 (50g, 0.26mol, 1.0 eq). The reaction was maintained at 0-10°C and stirred for 2h. Then the reactant was transferred to a 1L single-port RBF, and concentrated under vacuum at 30-40°C until no more distillate was observed, and a light brown viscous substance was obtained.

Add 200 mL of acetonitrile to the viscous crude product at 20-30°C to obtain a homogeneous reactant. Add 30g NaHCO _{3 at} 20-30°C. The reactant was stirred for 1 hour, and then concentrated under vacuum at 30-40°C to completely remove the acetonitrile to obtain a light orange suspended viscous substance. Then 100mL methanol and 300mL dichloromethane were added at 20～30℃, the reactant was stirred for 20min, filtered through a sintered glass funnel, and concentrated under vacuum at 30～40℃ to remove the mixed solvent, to obtain 160g of light brown transparent viscous substance, crude The yield was 116%, and the HPLC purity was 95% (the α-isomer of compound 4 was not detected).

Step 3: Preparation of compound 5

Prepare clean and dry 2L three-port RBF, equipped with mechanical stirrer and thermometer. Under the protection of nitrogen, compound 4 (170 g, 0.32 mol, 1.0 eq.) and 150 mL of methanol were added at 20 to 30°C, and the reaction solution was cooled to -10 to -5°C. Then slowly add 490mL (1.0M) ammonia water. The reaction solution was heated to -5 to 0°C and stirred for 14 hours. According to the NMR results, 230 mL (2.8M) ammonia water was added within 30 min at -10 to -5°C and stirred for 10 h. The reaction mixture was concentrated under reduced pressure at 30-40°C to obtain a crude product. Then, 100 mL of water was added to the crude reaction product at 20-30° C. to obtain a suspension, and then it was passed through a suction filtration silica gel column containing 100 g of activated carbon to elute the product with approximately 1.5 L of water. According to the results of thin-layer chromatography (TLC), the high-concentration eluent was collected and distilled at 30-35°C until no more distillate was observed. Add n-heptane to the residue, and then concentrate under vacuum to remove water to obtain 86 g of crude product with a yield of 66% and an HPLC purity of 99.9%.

Step 4: Preparation of β-NMN (Compound 6)

Prepare a clean and dry 500mL three-port RBF, equipped with a mechanical stirrer and a thermometer. Compound 5 (40 g, 0.1 mol, 1.0 eq.) was added under nitrogen protection, and then PO(OMe) ₃ (120 mL, 3v) was added. The reactants are stirred at 20 to 30°C to make them homogeneous, and then cooled to -10 to 0°C with a refrigerator. _{Then, POCl 3} (68.3 g, 0.45 mol, 4.5 eq.) was slowly added within 30 min at -10 to 0°C, and the reaction solution was heated to 0°C and stirred for 24 hours. HPLC monitored until the reaction was complete, the reaction was washed with MTBE at 20-30°C, and the reaction was quenched with cold water at 20-30°C.

Prepare clean and dry 2L three-port RBF, equipped with mechanical stirrer and thermometer. Add the quenched reactant under an open atmosphere, and then add alkaline resin (D301) to adjust the pH to 6. The reactant is filtered, and the filter residue is washed with deionized water at 20-30°C. The filtrate was concentrated at 30-35°C to obtain 27 g of compound 6 with a yield of 82% and an HPLC purity of 99.9%.

It should be noted that the specific features, structures, materials or characteristics described in this specification can be combined in any one or more embodiments in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments and the features of the different embodiments described in this specification without contradicting each other.

Claims (20)

1. The method for synthesizing nicotinamide mononucleotide intermediate shown in formula III is characterized in that: compounds I and II are reacted under the action of Lewis acid to obtain;

   

   Wherein, R ₁ , R ₂ , and R _{3 are} independently selected from acetyl or benzoyl.
2. The synthesis method according to claim 1, wherein the Lewis acid is selected from at least one of TMSOTf, ZnCl ₂ , TiCl ₄ , Ti(OiPr) ₂ , AlCl ₃ , SnCl ₂ , and BF ₃ .
3. The synthesis method according to claim 2, characterized in that the feeding amount of compound II is 1 eq., and the feeding amount of TMSOTf is 0.5 to 2.5 eq.; preferably, the feeding amount of TMSOTf is 1.6 eq.
4. The synthesis method according to claim 1, wherein the reaction solvent is selected from at least one of methylene chloride, dichloroethane, and acetonitrile.
5. The synthesis method according to claim 1, wherein the reaction is carried out under a protective atmosphere; preferably, the protective atmosphere is a nitrogen atmosphere.
6. The synthesis method according to claim 1, wherein the reaction temperature is 0-10°C.
7. The synthesis method according to claim 1, characterized in that the feeding amount of compound II is 1 eq., and the feeding amount of compound I is 1.0 to 1.1 eq.
8. The synthesis method according to any one of claims 1-7, characterized in that: compound II is prepared by the following method: the raw material SM-1 reacts with the silylation reagent to obtain:

   
9. The synthesis method according to claim 8, characterized in that the feed amount of the raw material SM-1 is 1 eq., and the feed amount of the silylation reagent is 1.2 eq.
10. The synthesis method according to claim 8 or 9, wherein the silylation reagent is selected from at least one of TMSF, TMSCl, TMSBr, TMSI, and TMSOTf.
11. The synthesis method according to claim 8, wherein the reaction solvent is hexamethyldisilazane.
12. The synthesis method according to claim 8, wherein the reaction temperature is 100-150°C.
13. The preparation method of nicotinamide mononucleotide is characterized in that it comprises the following steps:

    a. The intermediate Ⅲ is obtained according to the synthetic method of any one of claims 1-12;

    b. Intermediate III removes the protective group to obtain Intermediate IV:

    

    c. Phosphorylation of intermediate IV to obtain nicotinamide mononucleotide:

    
14. The preparation method according to claim 13, characterized in that: in step b, the intermediate III is placed in a base alcohol solution to react to remove the protective group.
15. The preparation method according to claim 14, wherein the base is selected from at least one of NH ₃ , triethylamine, diisopropylethylamine, NaOH, LiOH, KOH, NaOEt, and KOEt.
16. The preparation method according to claim 14, wherein the alcohol is selected from at least one of ^{MeOH, EtOH, n} PrOH, ⁱ PrOH, ⁿ BuOH, ⁱ BuOH, and ^{t BuOH.}
17. The preparation method according to claim 13, wherein the reaction temperature in step b is -10 to 0°C.
18. The preparation method according to claim 13, characterized in that: step c uses at least one of the following phosphorylation reagents: POCl ₃ , POCl(OEt) ₂ , POCl(OMe) ₂ , POCl(OBn) ₂ .
19. The preparation method according to claim 13, wherein the reaction solvent in step c is selected from at least one of _{PO(OEt) 3} , PO(OMe) _{3 and MeCN.}
20. The preparation method according to claim 13, wherein the reaction temperature in step c is -10 to 0°C.