Method for the catalytic synthesis of a unique chiral 2-aryl-substituted nitrogenous heterocyclic derivative using an imine reductase and use thereof

Abstract

A method for the catalytic synthesis of a unique chiral 2-aryl-substituted nitrogen heterocyclic derivative using an imine reductase, and the use thereof, is disclosed. The method comprises converting, under the catalysis of an imine reductase, a compound represented by formula II into a unique chiral compound represented by formula I. In formulas I and II, each R is independently selected from hydrogen, fluorine, chlorine, bromine, C1–C6 alkyl, C1–C6 halogenated alkyl, C2–C6 alkenyl, C2–C6 alkynyl, cyano, nitro, or carboxyl; X is selected from –CH2– and –O–; and yn is an integer selected from 0 to 6.The imine reductase is selected from any of the following amino acid sequences or a combination of at least two of them: (1) an amino acid sequence as set out in any of the SEQ ID NOs: 2, 4, 6, 7 or 10; and (2) an amino acid sequence having imine reductase activity and having at least 90% identity with the sequence shown in any of the SEQ ID NOs: 2, 4, 6, 7 or 10.

Description

A method for synthesizing single chiral 2-aryl substituted nitrogen heterocyclic derivatives catalyzed by imine reductase and its application Technical Field

[0001] The present invention belongs to the field of biocatalytic synthesis, and particularly relates to a method for synthesizing single chiral 2-aryl-substituted nitrogen heterocyclic derivatives by using imine reductase as a catalyst and an application thereof. Background Art

[0002] Chiral drugs are pharmaceuticals composed of pharmacologically active chiral compounds. Different enantiomers of chiral drugs exhibit significant differences in pharmacology, pharmacokinetics, metabolism, toxicity, and immune responses. Fifty-six percent of currently used drugs are chiral molecules. Chiral amines and their derivatives are a key branch of chiral drugs, serving as building blocks for numerous pharmaceutical intermediates and agricultural chemicals. Chiral amines account for 40% of FDA-approved drugs, including neurological, antihypertensive, and cardiovascular medications.

[0003] Bioenzyme catalysts, characterized by mild reaction conditions, good specificity, high stereoselectivity, and optimized environments, are widely used in the synthesis of various chiral compounds, including chiral amines. Transaminases, for example, are used in drugs such as sitagliptin. However, due to the limitations of their reaction mechanism, transaminases are limited to the synthesis of chiral primary amines.

[0004] Imine reductase can catalyze the direct production of chiral secondary amines from imine compounds. It has the advantages of mild reaction conditions, good stereoselectivity, high conversion rate and low production cost, and has received increasing attention in recent years.

[0005] Chiral 2-aryl-nitrogen heterocycles are important building blocks, commonly found in natural products, pharmaceutical molecules, and synthetic intermediates. Functionalized chiral nitrogen heterocycles have recently been shown to possess diverse biological activities. However, chemical synthesis of chiral 2-aryl-nitrogen heterocycles requires multiple steps, involving the use of chiral derivatization reagents or metal catalysts. These methods are demanding, highly polluting, and difficult to achieve optical purity exceeding 98.0%. Yields are low, limiting practical large-scale production. Compared to traditional chemical synthesis, the use of imine reductases to catalyze the synthesis of chiral 2-aryl-nitrogen heterocycles offers advantages such as low production cost, a green process, and excellent atom economy. Recent studies, such as Bernhard et al. (Process Development of Enantioselective Imine Reductase-Catalyzed Syntheses of Pharmaceutically Relevant Pyrrolidines), have investigated the application of imine reductases in chiral 2-aryl-pyrrolidines. However, research on imine reductases in other structures, such as aromatic piperidines, is limited. Therefore, searching for and screening highly active and selective imine reductases for synthesizing chiral 2-aryl-nitrogen heterocycles including aromatic piperidines has research value and synthetic application prospects. Summary of the Invention

[0006] To address the shortcomings of the prior art, the present invention aims to provide a method for the synthesis of single-chiral 2-aryl-substituted nitrogen heterocycle derivatives catalyzed by imine reductase and its application. This invention utilizes a novel enzymatic catalysis technology to prepare single-chiral 2-aryl-nitrogen heterocycles, avoiding the problems of traditional chemical synthesis routes, such as the need for chiral derivatization reagents or metal catalysts, harsh reaction conditions, severe pollution, low chiral purity, and low yield.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for synthesizing a single chiral 2-aryl-substituted nitrogen heterocyclic derivative catalyzed by imine reductase, the method comprising:

[0009] The compound represented by formula II is converted into a single chiral compound represented by formula I under the catalysis of imine reductase;

[0010] In Formula I and Formula II, each R is independently selected from hydrogen, fluorine, chlorine, bromine, C1-C6 alkyl, halogenated C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, cyano, nitro or carboxyl;

[0011] X is selected from -CH2- or -O-;

[0012] n is selected from an integer between 0 and 6; n can be, for example, 0, 1, 2, 3, 4, 5 or 6. When n is 0, R does not exist;

[0013] The imine reductase is selected from the amino acid sequences shown in any one or a combination of at least two of the following:

[0014] (1) the amino acid sequence shown in any one of SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 6, SEQ ID NO: 7 or SEQ ID NO: 10;

[0015] (2) An amino acid sequence that is at least 90% identical to the sequence shown in any one of SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 6, SEQ ID NO: 7, or SEQ ID NO: 10 and has imine reductase activity.

[0016] In the present invention, the sources of the imine reductase include Myxococcus stipitatus, Mycolicibacterium mageritense, Burkholderia contaminans FFH2055, Paenibacillus mucilaginosus, and Luteolibacter luteus.

[0017] Preferably, the compound represented by Formula II is converted into the S-type compound represented by Formula I under the catalytic action of any one or a combination of at least two of the imine reductases represented by SEQ ID NO: 2, SEQ ID NO: 6 or SEQ ID NO: 10.

[0018] Preferably, the compound represented by Formula II is converted into the R-form compound represented by Formula I under the catalytic action of any one or a combination of the imine reductase represented by SEQ ID NO: 4 or SEQ ID NO: 8.

[0019] Preferably, the method for synthesizing a single chiral 2-aryl-substituted nitrogen heterocyclic derivative catalyzed by imine reductase comprises:

[0020] The compound represented by formula II, imine reductase powder and buffer solution are prepared into a reaction system, and a catalytic reaction is carried out to obtain the product represented by formula I;

[0021] Alternatively, the compound represented by formula II, cells containing imine reductase and a buffer solution are prepared into a reaction system, and a catalytic reaction is carried out to obtain the product represented by formula I.

[0022] Preferably, the reaction system further includes a coenzyme.

[0023] Preferably, the coenzyme is selected from NAD + , NADH, NADP + or NADPH, any one or a combination of at least two.

[0024] Preferably, the coenzyme is NADP + .

[0025] Preferably, the reaction starting concentration of the coenzyme is 0.02-0.4 g / L, for example, it can be 0.02 g / L, 0.05 g / L, 0.1 g / L, 0.15 g / L, 0.2 g / L, 0.25 g / L, 0.3 g / L, 0.35 g / L or 0.4 g / L, etc., preferably 0.05-0.1 g / L, for example, it can be 0.05 g / L, 0.06 g / L, 0.07 g / L, 0.08 g / L, 0.09 g / L or 0.1 g / L, etc.

[0026] Preferably, the reaction system further comprises a co-substrate, and the co-substrate is selected from any one or a combination of at least two of isopropanol, glucose or ammonium formate.

[0027] Preferably, the co-substrate is glucose.

[0028] Preferably, the reaction starting concentration of the co-substrate is 20-50 g / L, for example, 20 g / L, 25 g / L, 30 g / L, 35 g / L, 40 g / L, 45 g / L or 50 g / L, etc., preferably 30-40 g / L.

[0029] Preferably, the reaction system further comprises an enzyme for coenzyme regeneration, and the enzyme for coenzyme regeneration is selected from any one of alcohol dehydrogenase, formate dehydrogenase or glucose dehydrogenase, or a combination of at least two thereof.

[0030] Preferably, the enzyme for coenzyme regeneration is glucose dehydrogenase.

[0031] Preferably, the reaction starting concentration of the enzyme for coenzyme regeneration is 0.02-0.4 g / L, for example, it can be 0.02 g / L, 0.05 g / L, 0.1 g / L, 0.15 g / L, 0.2 g / L, 0.25 g / L, 0.3 g / L, 0.35 g / L or 0.4 g / L, etc., preferably 0.05-0.1 g / L.

[0032] Preferably, the reaction starting concentration of the compound represented by Formula II in the reaction system is 1-100 g / L, for example, it can be 1 g / L, 10 g / L, 20 g / L, 30 g / L, 40 g / L, 50 g / L, 60 g / L, 70 g / L, 80 g / L, 90 g / L or 100 g / L, etc., preferably 20-80 g / L, more preferably 30-50 g / L.

[0033] Preferably, the initial reaction concentration of the imine reductase powder in the reaction system is 1-20 g / L, for example, 1 g / L, 2 g / L, 4 g / L, 6 g / L, 8 g / L, 10 g / L, 12 g / L, 14 g / L, 16 g / L, 18 g / L or 20 g / L, etc., preferably 5-10 g / L.

[0034] Preferably, the initial reaction concentration of the cells containing imine reductase in the reaction system is 5-100 g / L, for example, 5 g / L, 10 g / L, 20 g / L, 30 g / L, 40 g / L, 50 g / L, 60 g / L, 70 g / L, 80 g / L, 90 g / L or 100 g / L, etc., preferably 20-80 g / L, more preferably 40-60 g / L.

[0035] In the present invention, the reaction system is a buffered saline solution system, and the pH of the reaction system is controlled by the buffer solution.

[0036] Preferably, the buffer is selected from any one or a combination of at least two of potassium phosphate buffer, Tris-hydrochloride buffer, ammonium chloride buffer, ammonium formate buffer or ammonium acetate buffer.

[0037] Commonly used buffers include, but are not limited to, potassium phosphate buffer, tris-hydrochloride (Tris-HCl), ammonium chloride (NH4Cl), ammonium formate (HCOONH4) or ammonium acetate (CH3COONH4) buffer.

[0038] Preferably, the buffer is potassium phosphate buffer.

[0039] Preferably, the concentration of potassium phosphate in the potassium phosphate buffer is 20-200 mM, for example, 20 mM, 25 mM, 50 mM, 75 mM, 100 mM, 125 mM, 150 mM, 175 mM or 200 mM, etc., preferably 90-100 mM.

[0040] Preferably, the reaction system further comprises a co-solvent, which is selected from any one or a combination of at least two of dimethyl sulfoxide, methanol, ethanol, isopropanol or acetone;

[0041] Preferably, the cosolvent is dimethyl sulfoxide.

[0042] In the present invention, the cosolvent used should be miscible with water to further increase the solubility of the substrate.

[0043] In a specific embodiment of the present invention, the technical solution adopted by the present invention is as follows:

[0044] Preferably, the reaction time of the catalytic reaction is 12-36 hours, for example, it can be 12, 16, 20, 24, 28, 32 or 36, etc., preferably 20-24 hours.

[0045] Preferably, the reaction temperature of the catalytic reaction is 25-40°C, for example, it can be 25°C, 27°C, 29°C, 31°C, 33°C, 35°C, 37°C, 39°C or 40°C, etc., preferably 30-37°C.

[0046] Preferably, the pH of the reaction system of the catalytic reaction is 6.0-8.0, for example, it can be 6.0, 6.5, 7.0, 7.5 or 8, etc., preferably 7.0-7.5.

[0047] Preferably, the imine reductase powder is obtained by fermentation of genetically engineered bacteria.

[0048] Preferably, the genetically engineered bacteria is genetically engineered Escherichia coli or yeast, preferably Escherichia coli.

[0049] Preferably, the genetic engineering modification comprises introducing a nucleotide encoding the imine reductase into Escherichia coli or yeast, and expressing the imine reductase in Escherichia coli or yeast.

[0050] Preferably, the nucleotide encoding the imine reductase is selected from the sequence shown in any one or a combination of at least two of the following:

[0051] (I) the nucleotide sequence shown in any one of SEQ ID NO: 1, SEQ ID NO: 3, SEQ ID NO: 5, SEQ ID NO: 7 or SEQ ID NO: 9;

[0052] (II) a nucleotide sequence that is at least 90% identical to the sequence shown in any one of SEQ ID NO: 1, SEQ ID NO: 3, SEQ ID NO: 5, SEQ ID NO: 7, or SEQ ID NO: 9 and encodes an imine reductase.

[0053] Taking (S)-2-(4-fluorophenyl)-piperidine 5(a) and (R)-3-(3-bromo-5-chlorophenyl)-morpholine 10(b) prepared by the present invention as examples, the conversion rate is not less than 99%, and the enantiomeric excess value is not less than 99.0%. The present invention uses a novel enzyme catalysis technology to achieve the preparation of a single chiral 2-aryl-nitrogen heterocycle. The catalytic reaction is carried out using an imine reductase with a specific amino acid sequence. A coenzyme can also be added to the reaction as an electron carrier, and glucose dehydrogenase can be used in combination to implement the coenzyme cycle. This technical route is simple, has a high conversion rate, good selectivity, is environmentally friendly, and has the potential for industrial production.

[0054] In a second aspect, the present invention provides the use of the method for synthesizing a single chiral 2-aryl-substituted nitrogen heterocyclic derivative catalyzed by imine reductase according to the first aspect in the preparation of chiral drugs.

[0055] The numerical range described in the present invention includes not only the point values ​​listed above, but also any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0056] Compared with the existing technology, the present invention has the following beneficial effects: through a new enzyme catalysis technology, a single chiral 2-aryl-nitrogen heterocycle can be prepared, avoiding the problems of traditional chemical synthesis routes such as the need to use chiral derivatization reagents or metal catalysts, harsh reaction conditions, serious pollution, low chiral purity, and low yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 is the NMR spectrum of compound 10(b). DETAILED DESCRIPTION

[0058] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0059] If no specific techniques or conditions are specified in the examples, the experiments were carried out according to the techniques or conditions described in the literature in the field or according to the product instructions. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0060] Example 1: Synthesis and expression of imine reductase

[0061] The wild-type imine reductase encoding genes from Luteolibacter luteus, Burkholderia contaminans FFH2055, Paenibacillus mucilaginosus, Mycolicibacterium mageritense, and Myxococcus stipitatus were codon-optimized, and the corresponding DNA sequences were synthesized.

[0062] SEQ ID NO: 1 is a nucleotide sequence encoding an imine reductase from Myxococcus stipitatus;

[0063] SEQ ID NO: 2 is the amino acid sequence of imine reductase from Myxococcus stipitatus;

[0064] SEQ ID NO: 3 is a nucleotide sequence encoding an imine reductase from Mycolicibacterium mageritense;

[0065] SEQ ID NO: 4 is the amino acid sequence of imine reductase from Mycolicibacterium mageritense;

[0066] SEQ ID NO: 5 is a nucleotide sequence encoding an imine reductase derived from Burkholderia contaminans FFH2055;

[0067] SEQ ID NO: 6 is the amino acid sequence of imine reductase from Burkholderia contaminans FFH2055;

[0068] SEQ ID NO: 7 is a nucleotide sequence encoding an imine reductase from Paenibacillus mucilaginosus;

[0069] SEQ ID NO: 8 is the amino acid sequence of imine reductase from Paenibacillus mucilaginosus;

[0070] SEQ ID NO: 9 is a nucleotide sequence encoding an imine reductase from Luteolibacter luteus;

[0071] SEQ ID NO: 10 is the amino acid sequence of imine reductase from Luteolibacter luteus.

[0072] Each gene fragment was ligated into the plasmid pET28a(+). The recombinant plasmid was then transformed into Escherichia coli BL21(DE3) via chemical or electroporation. The bacterial suspension was plated on LB agar plates containing 50 μg / mL kanamycin and incubated overnight at 37°C. Transformants were selected for sequencing verification, and the correct transformants were named LlIR, BcIR, PmIR, MmIR, and MsIR.

[0073] The recombinant bacteria were inoculated into 5 mL of LB liquid medium containing 50 μg / mL kanamycin and cultured overnight at 37°C. 2 mL of the bacterial suspension was inoculated into 200 mL of LB liquid medium containing 50 μg / mL kanamycin and cultured at 37°C, 200 rpm for 3 hours. IPTG was then added to a final concentration of 50 mM and induced at 25°C, 200 rpm for 16 hours. The cells were then centrifuged at 9000 rpm, 4°C for 10 minutes to obtain wet cells containing the corresponding imine reductases. The collected wet cells were freeze-dried at -80°C to obtain the corresponding imine reductase powders, designated as LlIR, BcIR, PmIR, MmIR, and MsIR.

[0074] Example 2: Synthesis of 6-(4-fluorophenyl)-2,3,4,5-tetrahydropyridine

[0075] In a four-necked flask with magnetic stirring, 5.97 g (30 mmol) of lactam 2 was dissolved in THF (100 mL). The temperature was cooled to -30°C, and 6.57 g (33 mmol) of Grignard reagent 1 was added dropwise. The mixture was stirred for 1 h. The reaction solution was quenched with 1 M HCl (100 mL) and extracted with MTBE (100 mL x 3). The organic phase was washed with saturated brine, dried over anhydrous MgSO4, filtered, and distilled under reduced pressure to obtain 7.96 g (27 mmol) of N-Boc aryl ketone 3. 7.96 g (27 mmol) of N-Boc aryl ketone 3 was dissolved in DCM (15 mL), cooled to 0°C, TFA (15 mL) was added dropwise, and the mixture was stirred for 2 h. 30% NaOH was added dropwise to adjust the pH to 10-11. MTBE was added for extraction (100 mL × 3). The organic phase was washed with saturated brine, dried over anhydrous MgSO4, filtered, and distilled under reduced pressure to obtain 4.3 g of aryl intracyclic imine 4 (yield 81%).

[0076] Example 3: 6-(4-fluorophenyl)-2,3,4,5-tetrahydropyridine pilot test

[0077] Weigh 10.0 mg of imine reductase powder (LlIR, BcIR, PmIR, MmIR, MsIR) into the corresponding 5 mL centrifuge tube, add 2 mg of GDH, 20 mg of glucose, 2 mg of NADP, respectively. + A solution of 20 mg of compound 4 (6-(4-fluorophenyl)-2,3,4,5-tetrahydropyridine) and 20 μL of DMSO was added to 0.1 M pH 7.0 phosphate buffer and the volume was adjusted to 1.0 mL. The mixture was shaken at 30°C for 24 hours and analyzed by UPLC and chiral HPLC. The conversion and ee values ​​are shown in Table 1 below.

[0078] Table 1

[0079] Example 4: 6-(4-Fluorophenyl)-2,3,4,5-tetrahydropyridine gram-scale experiment

[0080] 1.0 g of raw material 6-(4-fluorophenyl)-2,3,4,5-tetrahydropyridine and 2% vv -1 DMSO, NADP + 0.05 g of PEG-1, 0.05 g of GDH, 2.0 g of glucose, and 0.1 M pH 7.0 phosphate buffer were diluted to 30 mL and stirred to initiate the reaction. The temperature was controlled at 30°C in a constant temperature water bath. The pH was controlled at 7.0 using a titrator with 3 M sodium carbonate solution. Finally, 1.5 g of wet BcIR cells were added to the reaction system. After 24 hours, Conv (%) was >99.0% and ee >99.0% (S) were detected.

[0081] Example 5: Synthesis of 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine

[0082] In a four-necked flask with magnetic stirring, 6.03 g (30 mmol) of lactam 7 was dissolved in THF (100 mL). The temperature was cooled to -30°C, and 9.70 g (33 mmol) of Grignard reagent 6 was added dropwise. The mixture was stirred for 1 h. The reaction solution was quenched with 1 M HCl (100 mL) and extracted with MTBE (100 mL x 3). The organic phase was washed with saturated brine, dried over anhydrous MgSO4, filtered, and distilled under reduced pressure to obtain 9.97 g (25.5 mmol) of N-Boc aryl ketone 8. N-Boc aryl ketone 8, 9.97 g (25.5 mmol) was dissolved in DCM (15 mL), cooled to 0°C, TFA (15 mL) was added dropwise, and the mixture was stirred for 2 h. 30% NaOH was added dropwise to adjust the pH to 10-11. MTBE was added for extraction (100 mL × 3). The organic phase was washed with saturated brine, dried over anhydrous MgSO4, filtered, and distilled under reduced pressure to obtain aryl intracyclic imine 9, 5.57 g, with a yield of 68%.

[0083] Example 6: 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine pilot experiment

[0084] Weigh 10.0 mg of imine reductase (LlIR, BcIR, PmIR, MmIR, MsIR) into the corresponding 5 mL centrifuge tube, add 2 mg of GDH, 20 mg of glucose, 2 mg of NADP, respectively. + 20 mg of 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine and 20 μL of DMSO were added to a 0.1 M pH 7.0 phosphate buffer solution and the volume was adjusted to 1.0 mL. The mixture was then shaken at 30°C for 24 hours, and the conversion rate and chirality were measured. The results are shown in Table 2 below:

[0085] Table 2

[0086] Example 7: 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine gram scale experiment

[0087] To a 50 mL four-necked flask, 1.0 g of raw material 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine and 2% vv -1 DMSO, NADP + 0.05 g of PEG-1, 0.05 g of GDH, 2.0 g of glucose, and 0.1 M pH 7.0 phosphate buffer were diluted to 30 mL and stirred to start the reaction. The temperature was controlled at 30°C in a constant temperature water bath and the pH was controlled at 7.0 with a 3 M sodium carbonate solution in a titrator. Finally, 1.5 g of wet cells LlIR were added to the reaction system. After 24 hours, Conv (%) was >99.0% and ee >99.0% (R) were detected.

[0088] Example 8: Ten-gram experiment of 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine

[0089] To a 500 mL four-necked flask, 10.0 g of raw material 5-(3-bromo-5-chlorophenyl)-3,6-dihydro-1,4-oxazine and 2% vv -1 DMSO, NADP + 0.5 g of PEG-1, 0.5 g of GDH, 20.0 g of glucose, and 0.1 M pH 7.0 phosphate buffer were diluted to 300 mL and stirred to start the reaction. The temperature was controlled at 30°C in a constant temperature water bath and the pH was controlled at 7.0 with a 3 M sodium carbonate solution in a titrator. Finally, 15.0 g of wet cells LlIR were added to the reaction system. 24 hours later, Conv (%) was >99.0% and ee >99.0% (R) were detected.

[0090] The applicant declares that the above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention fall within the scope of protection and disclosure of the present invention.

Claims

1. A method for the catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase, characterized in that, The method includes: The compound shown in Formula II is converted into the compound shown in Formula I with a single chirality under the catalysis of imine reductase; In Formula I and Formula II, each R is independently selected from hydrogen, fluorine, chlorine, bromine, C1-C6 alkyl, halogenated C1-C6 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, cyano, nitro or carboxyl; X is selected from -CH2- or -O-; n is an integer between 0 and 6; The imine reductase is selected from the amino acid sequences shown by any one or a combination of at least two of the following: (1) The amino acid sequence shown by any one of SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:7 or SEQ ID NO:10; (2) An amino acid sequence having at least 90% identity with the sequence shown by any one of SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6, SEQ ID NO:7 or SEQ ID NO:10 and having imine reductase activity.

2. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to claim 1, wherein, The compound shown by Formula II is converted into the compound shown by Formula I in the S form under the catalysis of any one or a combination of at least two of the imine reductases shown by SEQ ID NO:2, SEQ ID NO:6 or SEQ ID NO:10; Preferably, the compound shown by Formula II is converted into the compound shown by Formula I in the R form under the catalysis of any one or a combination of two of the imine reductases shown by SEQ ID NO:4 or SEQ ID NO:

8.

3. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to claim 1 or 2, characterized in that, The method includes: Formulating the compound shown by Formula II, imine reductase enzyme powder and buffer solution into a reaction system, and performing a catalytic reaction to obtain the product shown by Formula I; Or, formulating the compound shown by Formula II, cells containing imine reductase and buffer solution into a reaction system, and performing a catalytic reaction to obtain the product shown by Formula I.

4. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacycle derivative by imine reductase according to claim 3, wherein, The reaction system further includes a coenzyme; Preferably, the coenzyme is selected from NAD + , NADH, NADP + or any combination of one or at least two of NADPH; Preferably, the coenzyme is NADP + ; Preferably, the starting reaction concentration of the coenzyme is 0.02 - 0.4 g / L, preferably 0.05 - 0.1 g / L.

5. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to claim 3 or 4, characterized in that, The reaction system further includes a cosubstrate, and the cosubstrate is selected from any one or a combination of at least two of isopropanol, glucose or ammonium formate; Preferably, the cosubstrate is glucose; Preferably, the starting reaction concentration of the cosubstrate is 20 - 50 g / L, preferably 30 - 40 g / L; Preferably, the reaction system further includes an enzyme for coenzyme regeneration, and the enzyme for coenzyme regeneration is selected from any one or a combination of at least two of alcohol dehydrogenase, formate dehydrogenase or glucose dehydrogenase; Preferably, the enzyme for coenzyme regeneration is glucose dehydrogenase; Preferably, the starting reaction concentration of the enzyme for coenzyme regeneration is 0.02 - 0.4 g / L, preferably 0.05 - 0.1 g / L.

6. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to any one of claims 3-5, characterized in that, The starting reaction concentration of the compound shown by Formula II in the reaction system is 1 - 100 g / L, preferably 20 - 80 g / L, and more preferably 30 - 50 g / L; Preferably, the starting reaction concentration of the imine reductase enzyme powder in the reaction system is 1 - 20 g / L, preferably 5 - 10 g / L; Preferably, the initial reaction concentration of the cells containing imine reductase in the reaction system is 5-100 g / L, preferably 20-80 g / L, and more preferably 40-60 g / L.

7. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to any one of claims 3-6, characterized in that, The buffer solution is selected from any one or a combination of at least two of potassium phosphate buffer solution, tris(hydroxymethyl)aminomethane-hydrochloride buffer solution, ammonium chloride buffer solution, ammonium formate buffer solution or ammonium acetate buffer solution; Preferably, the buffer solution is potassium phosphate buffer solution; Preferably, the concentration of potassium phosphate in the potassium phosphate buffer solution is 20-200 mM, preferably 90-100 mM; Preferably, the reaction system further includes a cosolvent, and the cosolvent is selected from any one or a combination of at least two of dimethyl sulfoxide, methanol, ethanol, isopropanol or acetone; Preferably, the cosolvent is dimethyl sulfoxide.

8. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to any one of claims 3-7, characterized in that, The reaction time of the catalytic reaction is 12-36 hours, preferably 20-24 hours; Preferably, the reaction temperature of the catalytic reaction is 25-40 °C, preferably 30-37 °C; Preferably, the pH of the reaction system of the catalytic reaction is 6.0-8.0, preferably 7.0-7.

5.

9. The method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by imine reductase according to any one of claims 3-8, characterized in that, The imine reductase enzyme powder is obtained by fermenting genetically engineered bacteria; Preferably, the genetically engineered bacteria are genetically engineered Escherichia coli or yeast, preferably Escherichia coli; Preferably, the genetic engineering transformation includes introducing the nucleotide encoding the imine reductase into Escherichia coli or yeast, and expressing the imine reductase in Escherichia coli or yeast; Preferably, the nucleotide encoding the imine reductase is selected from any one or a combination of at least two of the sequences shown in the following: (I) The nucleotide sequence shown in any one of SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7 or SEQ ID NO:9; (II) A nucleotide sequence having at least 90% identity with the sequence shown in any one of SEQ ID NO:1, SEQ ID NO:3, SEQ ID NO:5, SEQ ID NO:7 or SEQ ID NO:9 and encoding an imine reductase.

10. Use of the method for catalytic synthesis of a single chiral 2-aryl-substituted azacyclic derivative by the imine reductase according to any one of claims 1-9 in the preparation of chiral drugs.