Preparation method of eribulin intermediate

Abstract

The invention provides a preparation method of a compound as shown in a formula I. The preparation method comprises the following steps: starting from a compound 3A or a compound 3B, carrying out selective acylation by a biological enzyme A or selective hydrolysis by a biological enzyme B, reacting hydroxyl with a required configuration with acid anhydride under the action of organic alkali and a catalyst by using acid anhydride to obtain a compound 5, increasing the water solubility of an intermediate product, and carrying out extraction separation to obtain a compound 5; the separation of two configurations is realized, the ee value can reach 99% or above, and the preparation method is simple to operate, high in conversion rate, good in selectivity, low in cost and beneficial to industrial large-scale production.

Description

A preparation method of eribulin intermediate

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on July 29, 2022, with application number 202210904052.6 and invention name “A method for preparing an eribulin intermediate”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention belongs to the field of pharmaceutical chemistry, and in particular relates to a method for preparing an eribulin intermediate. Background Art

[0003] Eribulin mesylate is a synthetic analog of halichondrin B, sharing the biologically active macrocyclic moiety of halichondrin B. Halichondrin B is a polyether macrolide that exhibits potent anticancer effects in both cell and animal models. Eribulin mesylate inhibits mitotic tubulin production, leading to irreversible G2 / M cell cycle arrest and mitotic spindle fragmentation. Prolonged mitotic arrest is followed by apoptosis and suppressed cell proliferation. Eribulin mesylate injection, developed by Eisai Inc., was approved by the US FDA in November 2010 for marketing in the United States under the trade name Halaven. It is indicated for patients with metastatic breast cancer who have received at least two prior treatment regimens for metastatic cancer. Subset analysis has shown that eribulin mesylate is effective in treating triple-negative metastatic breast cancer, an aggressive form of breast cancer with a poor prognosis. In many countries, eribulin mesylate was once considered a third-line or even later-line treatment for metastatic breast cancer. However, it remains the only chemotherapy agent that can effectively improve patient survival. Currently, eribulin mesylate is the only drug in this field with promising clinical and market prospects.

[0004] The structure of the early intermediate of Eribulin is shown in Formula I below:

[0005]

[0006] The prior art method for synthesizing the compound represented by formula I is as follows:

[0007] The process route for the synthesis of the early intermediate I of Eisai, the original research manufacturer, for the raw material of eribulin is as follows:

[0008]

[0009] Among them, TBDPS is tert-butyldiphenylsilyl.

[0010] The hydroxyl carbon protected by the p-toluenesulfonyl group in compound I is chiral, and a racemate is initially obtained during the synthesis process. Literature reports (Synlett (2013), 24(3), 327-332, WO2005118565, etc.) have reported that a single configuration was obtained by preparing and separating the compound of formula 3 using a chiral simulated moving bed (SMB). This preparation is inefficient and costly, making it difficult to scale up production. In addition, a literature report (Org. Lett., Vol. 10, No. 14, 2008) has reported that a single configuration product was obtained under the catalysis of a chiral ligand and metallic chromium, but the cost is high.

[0011] Summary of the Invention

[0012] The technical problem to be solved by the present invention is to provide a method for preparing the compound represented by formula I, which is completely different from the prior art. The reaction conditions involved are mild and environmentally friendly, the route is novel, and the post-treatment and purification are simple. The prepared compound represented by formula I has high purity, and the preparation method is simple to operate, has a high conversion rate, good selectivity, and low cost, which is conducive to industrial scale-up production. The compound represented by formula I can be used in the preparation of eribulin drugs.

[0013] In a first aspect, the present invention provides a method for preparing a chiral compound I by an enzymatic method, comprising the following steps:

[0014] Method 1:

[0015]

[0016] The first method uses the compound shown in Formula 3A as a raw material, undergoes an acylation reaction with an acylating agent under the action of a biological enzyme A to obtain compound 4 and compound 1, and selectively separates the mixture of compound 4 and compound 1;

[0017] Method 2:

[0018]

[0019] The second method is to use the compound shown in Formula 3B as a raw material, hydrolyze it under the action of biological enzyme B and alkali to obtain compound 4 and compound 1, and selectively separate the mixture of compound 4 and compound 1;

[0020] Wherein, R1 is C1-C substituted or unsubstituted by Ra 12 Straight chain or branched chain acyl, benzoyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra; the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C18 The heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl, more preferably acetyl, propionyl, butyryl, benzoyl or acryloyl.

[0021] As a further improvement of the present invention, the biological enzyme A is a lipase or an esterase, and the biological enzyme A is selected from lipase AK (Lipase AK "Amano"), lipase from Pseudomonas fluorescens (Amano Lipase from pseudomonas fluorescens), Antarctic Candida lipase B immobilized on acrylic resin (CAL-B lipase immobilized on acrylic resin (Novozym 435)), lipase AS (Lipase AS "Amano"), lipase PS (Lipase PS "Amano" SD), lipase from Thermomyces lanuginosus, lipase from Candida Rugosa, lipase AYS (Lipase AYS "Amano"), triacylglycerol lipase, lipase from Mucor miehei or lipase from Rhizopus oryzae any one of Rhizopus oryzae, lipase B Candida antarctica immobilized on Immobead 150, recombinant from Aspergillus oryzae; and biological enzyme A is preferably lipase AK (Lipase AK "Amano"), lipase from Pseudomonas fluorescens (Amano Lipase from pseudomonas fluorescens), or CAL-B lipase (Novozym 435) immobilized on acrylic resin.

[0022] As a further improvement of the present invention, the biological enzyme B of method 2 is a lipase, an esterase or a hydrolase, such as lipase TL, lipase PS-30 from Pseudomonas cepacia, lipase QLM, lipase from Thermomyces lanuginosus, lipase P2 from Pseudomonas cepacia, lipase PS from Pseudomonas stutzeri, lipase RS from Rhizopus sp., lipase PS from Pseudomonas cepacia, lipase AN from Aspergillus niger, lipase A from Achromobacter sp., lipase AS1 from Alcaligenes sp., lipase AS2 from Alcaligenes sp., lipase AS3 from Candida cylindrica. cylindracea, lipase C2 from Candida cylindracea, lipase C1 from Candida cylindracea, lipase lipozym TL 1M, lipase lipozym TL 100L, Candida antarctica lipase B (CALB), CHIRAZYME E-1 pig liver esterase, lipase from Pseudomonas sp. L-6, Candida antarctica lipase A (CALA), Candida rugosa lipase (L-3), or pancreatic lipase USP Grade.

[0023] As a further improvement of the present invention, the acylating agent of method 1 is selected from vinyl ester or isopropenyl ester, wherein the vinyl ester is selected from C1-C 12 Straight chain or branched chain vinyl ester, vinyl benzoate, C3-C6 straight chain or branched chain vinyl ester substituted or unsubstituted by Rc; the isopropenyl ester is selected from C1-C6 substituted or unsubstituted by Rc 12 isopropenyl benzoate, isopropenyl benzoate, isopropenyl alkene acid substituted or unsubstituted by Rc. The substituent Rc of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 The heterocyclic aromatic group comprises a heteroatom selected from O, N or S.

[0024] As a further improvement of the present invention, the acylating agent of method 1 is preferably vinyl acetate, isopropylene acetate, vinyl propionate, isopropylene propionate, vinyl butyrate, isopropylene butyrate, vinyl isobutylate, isopropylene isobutylate, 2-methylvinyl butyrate, isopropylene 2-methylbutyrate, 3-methylvinyl butyrate, isopropylene 3-methylbutyrate, vinyl pivalate, isopropylene pivalate, vinyl 2-methylvalerate, isopropylene 2-methylvalerate, 3-methylvinyl valerate Ester, 3-methylisopropyl pentanoate, 4-methylvinyl pentanoate, 4-methylisopropyl pentanoate, vinyl hexanoate, isopropyl hexanoate, vinyl laurate, isopropyl laurate, vinyl benzoate, isopropyl benzoate, vinyl acrylate or isopropyl acrylate, more preferably vinyl acetate, isopropyl acetate, vinyl propionate, isopropyl propionate, vinyl butyrate, isopropyl butyrate, vinyl benzoate, isopropyl benzoate, vinyl acrylate or isopropyl acrylate.

[0025] The enzyme A of method 1 provided herein selectively acylates the alcohol of formula 3A to produce an acylated compound of formula 4 as a single isomer; the compound of formula 1 can then be conveniently separated from the compound of formula 4. The acylation reaction can be carried out in an organic solvent. The enantiomeric excess of the product of formula 1 is preferably at least 96% ee, more preferably at least 99% ee. The enzyme can be immobilized on a carrier to facilitate enzyme recovery and post-reaction processing. The enzyme exhibits high selectivity, good stability, high enzymatic activity, and low cost.

[0026] As a further improvement of the present invention, the acylation reaction of method 1 is carried out in an organic solvent A, which is selected from one or any combination of alkanes, aromatic hydrocarbons, chloroalkanes, nitriles or ether solvents; for example, alkanes are selected from one or any combination of n-hexane, cyclohexane, n-pentane, cyclopentane or n-heptane; aromatic hydrocarbons are selected from one or any combination of toluene, xylene or chlorobenzene; chloroalkanes are selected from dichloromethane and chloroform; nitriles are selected from one or any combination of acetonitrile, propionitrile or benzonitrile; ethers are selected from one or any combination of petroleum ether, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether or methyl tert-butyl ether (MTBE); organic solvent A is preferably one or any combination of petroleum ether, diethyl ether, methyl tert-butyl ether, dichloromethane, n-hexane, cyclohexane, n-pentane, cyclopentane, n-heptane, toluene or acetonitrile; more preferably one or any combination of n-hexane or n-heptane.

[0027] As a further improvement of the present invention, the mass volume ratio of compound 3A to organic solvent A in method 1 is 1 g:1-15 mL, more preferably 1 g:5-8 mL.

[0028] As a further improvement of the present invention, the acylation reaction temperature in method 1 is 30-80° C., preferably 55-60° C.; in this temperature range, the enzyme has good activity, fast reaction rate and high efficiency.

[0029] As a further improvement of the present invention, the mass ratio of compound 3A to biological enzyme A in method 1 is 1:0.005-0.3, preferably 1:0.01-0.3, and more preferably 1:0.05-0.2.

[0030] As a further improvement of the present invention, the molar ratio of compound 3A to the acylating agent in method 1 is 1:1 to 20, preferably 1:2 to 10, and more preferably 1:3 to 6; the acylating agent of the present invention is used in combination with a biological enzyme to selectively acylate the S-configured compound in the racemic compound 3A to obtain compound 4, with high reaction yield and good isomer purity.

[0031] As a further improvement of the present invention, the product obtained by the enantioselective acylation of the present invention comprises a mixture of the R-form of the compound of Formula I and the S-form of the compound of Formula 4. Similarly, enantioselective enzymatic hydrolysis can produce a mixture comprising the R-form of the compound of Formula I and the S-form of the compound of Formula 4. The optical purity of the compound of Formula I obtained by the optical resolution method of the present invention is generally at least 96% ee, preferably at least 97% ee, more preferably at least 98% ee, and most preferably at least 99% ee.

[0032] As a further improvement of the present invention, the hydrolysis reaction of method 2 is carried out in water and an organic solvent B, wherein the organic solvent B comprises one or any combination selected from alkanes, aromatic hydrocarbons, chlorinated alkanes, nitrile solvents or ether solvents; for example, alkanes are selected from one or any combination of n-hexane, cyclohexane, n-pentane, cyclopentane or n-heptane; aromatic hydrocarbons are selected from one or any combination of toluene, xylene or chlorobenzene; chlorinated alkanes are selected from one or any combination of dichloromethane or chloroform; nitriles are selected from one or any combination of acetonitrile, propionitrile or benzonitrile; ethers are selected from one or any combination of petroleum ether, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether or methyl tert-butyl ether (MTBE); and organic solvent B is preferably selected from one or any combination of toluene, xylene, methyl tert-butyl ether or acetonitrile.

[0033] As a further improvement of the present invention, the base is selected from an organic base or an inorganic base, the organic base is selected from one or any combination of diethylamine, triethylamine (TEA), diisopropylamine, morpholine, N-methylmorpholine, piperazine or N-methylpiperazine; the inorganic base comprises, for example, one or any combination of alkali metal hydroxides, carbonates or bicarbonates or alkaline earth metal hydroxides. Preferably, the base is an alkali metal hydroxide, an alkali metal carbonate or an alkali metal bicarbonate or any combination thereof, more preferably, the base is an alkali metal carbonate. The base is preferably selected from one or any combination of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium bicarbonate, sodium bicarbonate or potassium carbonate; most preferably, one or any combination of sodium carbonate or potassium carbonate. The base of the present invention is used in combination with biological enzyme B to selectively hydrolyze the R configuration in the racemic compound 3B to obtain compound I, with high reaction yield and good isomer purity.

[0034] As a further improvement of the present invention, the mass ratio of compound 3B to biological enzyme B in method 2 is 1:0.005-0.3, preferably 1:0.01-0.3, and more preferably 1:0.05-0.2.

[0035] As a further improvement of the present invention, the molar ratio of compound 3B to the base in method 2 is 1:1-10, preferably 1:1-8, and more preferably 1:1-4.

[0036] As a further improvement of the present invention, the mass volume ratio of compound 3B to organic solvent B in method 2 is 1 g:1-15 mL, more preferably 1 g:3-8 mL.

[0037] As a further improvement of the present invention, the hydrolysis reaction temperature in method 2 is 30-80° C., preferably 35-40° C.; in this temperature range, the enzyme has good activity, fast reaction rate and high efficiency.

[0038] As a further improvement of the present invention, the method for selectively separating the mixture of compound 4 and compound 1 comprises:

[0039] 1) separating the mixture of compound 4 and compound 1 by column chromatography to obtain compound 1; or

[0040] 2) Step a: In the presence of a catalyst and an organic base, compound I in the mixture of compound 4 and compound I selectively undergoes an esterification reaction with an acid anhydride to separate compound 4 and compound 5. Step b: Compound 5 is hydrolyzed to obtain compound I. The reaction formula is as follows:

[0041]

[0042] Wherein, R1 is C1-C substituted or unsubstituted by Ra 12Straight chain or branched chain acyl, benzoyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 Heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl; R2 is selected from

[0043] As a further improvement of the present invention, the column chromatography separation condition is to use petroleum ether:ethyl acetate with a volume ratio of 20:1 to 5:1 as the eluent for silica gel column chromatography separation.

[0044] As a further improvement of the present invention, in step a, the catalyst is selected from 4-dimethylaminopyridine (DMAP).

[0045] As a further improvement of the present invention, the molar ratio of compound I to catalyst in step a is 1:0.1-0.5, preferably 1:0.2-0.3.

[0046] As a further improvement of the present invention, the organic base in step a is selected from one of diethylamine, triethylamine, diisopropylamine, pyridine, α-picoline, 1,2-lutidine, 4-hydroxy-2-picoline, γ-collidine, quinoline or dimethylquinoline, or any combination thereof, and the organic base in step a is preferably selected from one of triethylamine, diisopropylamine, pyridine or α-picoline, or any combination thereof; the molar ratio of compound I to the organic base in step a is 1:1 to 10, preferably 1:1 to 5, more preferably 1:3 to 5; the temperature of the esterification reaction is 0 to 50°C, preferably 10 to 30°C.

[0047] As a further improvement of the present invention, the anhydride in step a is selected from The molar ratio of the compound I to the acid anhydride is 1:1-10, preferably 1:1-5, and more preferably 1:1.1-1.8.

[0048] As a further improvement of the present invention, the esterification reaction in step a is carried out in a reaction solvent C, which is selected from one or any combination of aromatic hydrocarbons, chlorinated alkanes, nitrile solvents or ether solvents; for example, aromatic hydrocarbons are selected from one or any combination of toluene, xylene or chlorobenzene; chlorinated alkanes are selected from one or any combination of dichloromethane or chloroform; nitriles are selected from one or any combination of acetonitrile, propionitrile or benzonitrile; ethers are selected from one or any combination of petroleum ether, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether or methyl tert-butyl ether; reaction solvent C is preferably selected from one or any combination of toluene, xylene, methyl tert-butyl ether or acetonitrile.

[0049] As a further improvement of the present invention, the separation in step a includes conventional separation steps, such as liquid separation, extraction, water washing or concentration. The present invention has no particular limitation on the solvent for liquid separation or extraction, and one or any combination of alkane, chlorinated alkane or ether solvents can be used; for example, the alkane is selected from one or any combination of n-hexane, cyclohexane, n-pentane, cyclopentane or n-heptane; the chlorinated alkane is selected from one or any combination of dichloromethane or chloroform; the ether is selected from one or any combination of petroleum ether, tetrahydrofuran, 1,4-dioxane, diethyl ether, diisopropyl ether or methyl tert-butyl ether (MTBE).

[0050] As a further improvement of the present invention, the hydrolysis in step b is carried out in water and an organic solvent D. Any organic solvent that does not produce negative effects is suitable for the hydrolysis reaction, and the organic solvent D is selected from an organic solvent that does not produce negative effects; the organic solvent D is preferably selected from the reaction solvent C in the above step a. Preferably, the hydrolysis is carried out in water and acetonitrile; the reaction temperature is preferably room temperature.

[0051] As a further improvement of the present invention, the hydrolysis in step b is carried out in an inorganic base, and the inorganic base is selected from one or any combination of alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates, or alkaline earth metal hydroxides. Preferably, the base is selected from one or any combination of alkali metal hydroxides or alkaline earth metal hydroxides, more preferably, the base is an alkali metal hydroxide. The base is preferably selected from one or any combination of lithium hydroxide, sodium hydroxide, potassium hydroxide, or barium hydroxide; more preferably, it is one or any combination of sodium hydroxide or potassium hydroxide.

[0052] As a further improvement of the present invention, the molar ratio of compound 5 to the inorganic base in step b is 1:1-20, preferably 1:1-4.

[0053] In a second aspect, the present invention provides a method for preparing a chiral compound I, comprising the step of separating a mixture of compound 4 and compound I, wherein the separation method comprises:

[0054] 3) separating the mixture of compound 4 and compound 1 by column chromatography to obtain compound 1; or

[0055] 4) Step a: In the presence of a catalyst and an organic base, compound I in the mixture of compound 4 and compound I selectively undergoes an esterification reaction with an acid anhydride to separate compound 4 and compound 5; Step b: Compound 5 is hydrolyzed to obtain compound I, as shown in the following reaction formula:

[0056]

[0057] Wherein, R1 is C1-C substituted or unsubstituted by Ra 12 A straight-chain or branched acyl group, a benzoyl group, a substituted or unsubstituted C3-C6 straight-chain or branched alkenoyl group, a substituent Ra of each group is independently selected from a C1-C6 straight-chain or branched alkyl group, a C1-C6 straight-chain or branched alkoxy group, a hydroxyl group, an amino group, a halogen group, a nitro group, a cyano group, a C1-C6 amide group, a C3-C6 cycloalkyl group, a C1-C6 sulfanyl group, a C1-C6 amide group, a C3-C6 cycloalkyl group, a phenyl group or a C3-C 18 Heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl; R2 is selected from

[0058] As a further improvement of the present invention, the reaction conditions of each step of compound I in the second aspect can refer to the reaction condition parameters of each step in the first aspect of the present invention mentioned above; when continuously feeding, whether it is through the acylation reaction of compound 3A in biological enzyme A or the hydrolysis reaction of compound 3B in biological enzyme B to obtain a mixture of compound I and compound 4, the feed can be accurately fed according to the theoretical yield of 50% or the amount detected by reference to high performance liquid chromatography (HPLC), without affecting the next step reaction with the anhydride step a.

[0059] As a further improvement of the present invention, compound 4 can be directly converted to compound I by hydrolysis with reference to the method in Synlett (2013), 24(3), 327-332 (the entire text of which is incorporated herein by reference).

[0060] As a further improvement of the present invention, the preparation of the mixture of compound 4 and compound 1 includes: subjecting compound 3A or compound 3B to selective acylation or hydrolysis under the action of biological enzyme A or biological enzyme B, respectively, to obtain a mixture of compound 4 and compound 1. The reaction formula is as follows:

[0061]

[0062] As a further improvement of the present invention, the reaction conditions in the preparation of the mixture of compound 4 and compound 1 in the second aspect can refer to the reaction conditions of each step in the first aspect of the present invention.

[0063] In a third aspect, the present invention provides a key intermediate for preparing compound I. In certain embodiments, the key intermediate compound C is represented as follows:

[0064] * represents chiral carbon; R is selected from C1-C 12 Straight chain or branched chain acyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra,

[0065] , wherein the substituents Ra of each group are independently selected from C1-C6 straight or branched alkyl, C1-C6 straight or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 The heterocyclic aromatic group comprises a heteroatom selected from O, N or S.

[0066] Preferably, when the chiral carbon represented by * is in S configuration, the structure is:

[0067]

[0068] Wherein: R1 is C1-C substituted or unsubstituted by Ra 12 A straight chain or branched chain acyl group, a C3-C6 straight chain or branched chain alkenoyl group which is substituted or unsubstituted by Ra, wherein the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide group, C3-C6 cycloalkyl group, C1-C6 sulfanyl group, C1-C6 amide group, C3-C6 cycloalkyl group, phenyl group or C3-C 18 A heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl or acryloyl.

[0069] As a further improvement of the present invention, the key intermediate compound is non-restrictively selected from the following compounds:

[0070]

[0071] When * indicates that the chiral carbon is in R configuration, the structure is:

[0072]

[0073] Wherein: R2 is selected from

[0074] As a further improvement of the present invention, the key intermediate compound is non-restrictively selected from the following compounds:

[0075]

[0076] In a third aspect, the present application provides a method for preparing an eribulin drug, which includes the method provided in the first aspect of the present application or the method provided in the second aspect of the present application.

[0077] Compared with the prior art, the present invention provides a novel method for preparing the compound represented by Formula I. The reaction conditions involved are mild and environmentally friendly, the route is novel, and the post-treatment and purification are simple. The prepared compound represented by Formula I has high purity, and the preparation method is simple to operate, has a high conversion rate, good selectivity, low cost, and is conducive to industrial scale-up production. The compound represented by Formula I can be used in the preparation of eribulin drugs. The advantages of the method for preparing Compound I are:

[0078] 1) The racemic compound 3 (including 3A or 3B) of the present invention does not require a high-cost SMB operation or the catalytic effect of a chiral ligand and metallic chromium. Instead, the compound 3 of the present invention can be selectively resolved by a screened biological enzyme (A or B) by column chromatography purification. Separation can be achieved by conventional filtration. Compared with the SMB chromatography method, the method is simple to operate, easy to scale up, and reduces the production cycle, thereby increasing production capacity.

[0079] 2) The biological enzyme screened by the present invention has the characteristics of high selectivity, good stability, high enzyme activity, recyclability and low cost.

[0080] 3) The present invention uses selective acylation by biological enzymes and finds that the racemic compound can be resolved by utilizing polarity differences. The yield of compound I is greater than 93% and the ee value is greater than 99%.

[0081] 4) The present invention more specifically adopts a bio-enzymatic resolution method to selectively protect the unwanted configuration with an acyl group, thereby reducing the polarity of the intermediate product. The desired configuration hydroxyl group is reacted with the acid anhydride in the presence of an organic base and a catalyst to increase the water solubility of the intermediate product. The unwanted configuration (the product protected by the acyl group) is extracted and removed by a low-polarity solvent. The two configurations can be separated without column chromatography purification, and the ee value can reach more than 99%. DETAILED DESCRIPTION

[0082] To facilitate understanding of the present invention by those skilled in the art, the technical solutions of the present invention will be further described below in conjunction with specific examples. However, the following does not limit the scope and spirit of the claims. Unless otherwise specified, all raw materials, reagents, or solvents used in the present invention were purchased from commercial channels. Experimental methods without specific conditions were carried out under conventional operating conditions in the art.

[0083] In the present invention, yield refers to the molar percentage of the actual yield of a product to the theoretical yield. "W" is the mass ratio. For example, 0.2w of enzyme means that the mass ratio of the enzyme to the raw materials (Compound 3A / Compound 3B) is 0.2.

[0084] Example 1

[0085]

[0086] Compound 3A (20.0 g, 44.70 mmol) was dissolved in 120 mL of n-heptane, and vinyl acetate (15.4 g, 223.48 mmol) and the enzyme Lipase AK "Amano" (4.0 g, 0.2 w) were added. Under nitrogen, the internal temperature was raised to 55-60°C and maintained at 55-60°C until the ee value of Compound I, as determined by HPLC, was ≥99%, indicating completion. The reaction solution was directly filtered, the filter cake was recovered, and the filtrate was concentrated to obtain the crude product, which was separated by silica gel column chromatography, distilled under reduced pressure, and concentrated to dryness to obtain 10.5 g of Compound 4-1 (48.0% yield) and 9.44 g of Compound I (47.2% yield, 99.8% ee).

[0087] Compound 4-1 1 H-NMR (400MHz, CDCl3): δ=7.68-7.65(m,4H),7.45-7.37(m,6H),5.62(s,1H),5.48(s,1H),5.22-5.16(m,1H),3.72-3.63(m ,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),2.03(s,3H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 25 H 33 BrO3Si] + 490.3,found 490.3.

[0088] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0089] Example 2

[0090] Except for following the following synthesis route and adjusting the parameters according to Table 1, the rest is the same as Example 1, and the NMR of the obtained product is as follows.

[0091]

[0092] Compound 4-2 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),5.61(s,1H),5.47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.6 7(m,1H)2.61-2.56(m,1H),2.38-2.29(m,2H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.13(t,3H,J=12.0Hz),1.05(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 35 BrO3Si] + 504.5,found 504.5.

[0093] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0094] Example 3

[0095] Except for following the following synthesis route and adjusting the parameters according to Table 1, the rest is the same as Example 1. The NMR of the obtained product is as follows.

[0096]

[0097] Compound 4-3 1 H-NMR (400MHz, CDCl3): δ = 8.07 (d, 2H, J = 9.2Hz), 7.70-7.67 (m, 4H), 7.55-7.31 (m, 9H), 5.63 (s, 1H), 5.49 (s, 1H), 5.23-5.17 (m, 1H),3.72-3.63(m,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 30 H 35 BrO3Si] + 552.4,found 552.4.

[0098] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63–1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C23 H 31 BrO2Si] + 448.2,found 448.2.

[0099] Example 4

[0100] Except for following the following synthesis route and adjusting the parameters according to Table 1, the rest is the same as Example 1, and the NMR of the obtained product is as follows.

[0101]

[0102] Compound 4-4 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),6.27(dd,1H,10.1Hz,4.4 Hz),6.05(dd,1H,9.8Hz,7.6Hz),5.61-5.59(m,2H),(s,1H),5.47(s,1H),5.21-5.15(m,1H ),3.71-3.62(m,2H),2.74-2.67(m,1H)2.61-2.56(m,1H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.07(s,9H).LC-MS(ESI):m / z calcd for[1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for C 26 H 33 BrO3Si] + 504.5,found 504.5.

[0103] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0104] Example 5

[0105]

[0106] Compound I (2.0 g, 4.47 mmol) was dissolved in 20 mL of acetonitrile, and pyridine (1.06 g, 13.41 mmol), 4-dimethylaminopyridine (DMAP) (0.11 g, 0.894 mmol), and succinic anhydride (0.67 g, 6.705 mmol) were added. Under nitrogen, the mixture was allowed to react at room temperature until the starting material spot disappeared as observed by thin-layer chromatography (TLC), indicating completion. The reaction solution was concentrated to obtain a light yellow oil, which was separated by silica gel column chromatography and evaporated under reduced pressure to dryness to obtain 2.35 g of compound 5-1 as a light yellow oil, with a yield of 96.0%.

[0107] 1 H-NMR (400MHz, CDCl3): δ = 10.98 (s, 1H), 7.67-7.65 (m, 4H), 7.43-7.37 (m, 6H), 5.61 (s, 1H), 5.48 (s, 1H), 5.24-5.1 8(m,1H),3.70-3.63(m,2H),2.74-2.54(m,6H),1.79-1.72(m,1H),1.69-1.52(m,3H),1.05(s,9H),LC-MS(ESI):m / z calcd for[C 27 H 35 BrO5Si] + 548.3,found 548.3.

[0108] Example 6

[0109] Except for following the following synthesis route and adjusting the parameters according to Table 2, the rest is the same as Example 5. The NMR of the obtained product is as follows.

[0110]

[0111] 1 H-NMR (400MHz, CDCl3): δ = 10.98 (s, 1H), 7.67-7.65 (m, 4H), 7.43-7.37 (m, 6H), 6.30 (dd, 2H, J = 21.4, 15.1Hz), 5.61 (s, 1H), 5.49 (s ,1H),5.24-5.18(m,1H),3.70-3.63(m,2H),2.59-2.56(m,2H),1.79-1.72(m,1H),1.69-1.52(m,3H),1.05(s,9H),LC-MS(ESI):m / z calcd for[C 27 H33 BrO5Si] + 546.4,found 546.4.

[0112] Example 7

[0113] Except for following the following synthesis route and adjusting the parameters according to Table 2, the rest is the same as Example 5. The NMR of the obtained product is as follows.

[0114]

[0115] 1 H-NMR (400MHz, CDCl3): δ = 10.98 (s, 1H), 8.33-8.29 (m, 2H), 7.91-7.87 (m, 2H), 7.67-7.65 (m, 4H), 7.43-7.37 (m, 6H), 5.61 (s, 1H), 5.4 9(s,1H),5.24-5.18(m,1H),3.70-3.63(m,2H),2.59-2.56(m,2H),1.79-1.72(m,1H),1.69-1.52(m,3H),1.05(s,9H),LC-MS(ESI):m / z calcd for[C 31 H 35 BrO5Si] + 596.2,found 596.2.

[0116] Example 8

[0117]

[0118] Compound 3B-1 (10.0 g, 20.43 mmol) was dissolved in 50 mL of toluene. Sodium carbonate (2.17 g, 20.43 mmol), lipase TL (1.0 g, 0.1 w), and water (1.5 g, 0.1 w) were added. Under nitrogen, the reaction was stirred at 35-40°C until the ee value of compound I, as determined by HPLC, was ≥99%, indicating completion. The reaction solution was directly filtered, the filter cake recovered, and the filtrate washed with saturated brine. The organic phase was concentrated to obtain a crude product, which was separated by silica gel column chromatography to obtain 4.81 g of compound 4-1 (48.1% yield) and 4.37 g of compound I (47.8% yield, 99.8% ee).

[0119] Compound 4-1 1H-NMR (400MHz, CDCl3): δ=7.68-7.65(m,4H),7.45-7.37(m,6H),5.62(s,1H),5.48(s,1H),5.22-5.16(m,1H),3.72-3.63(m ,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),2.03(s,3H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 25 H 33 BrO3Si] + 490.3,found 490.3.

[0120] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0121] Example 9

[0122] Except for following the following synthesis route and adjusting the parameters according to Table 3, the rest is the same as Example 8. The NMR of the obtained product is as follows.

[0123]

[0124] Compound 4-2 1H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),5.61(s,1H),5.47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2. 74-2.67(m,1H)2.61-2.56(m,1H),2.38-2.29(m,2H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.13(t,3H,J=12.0Hz).LC-MS(ESI):m / z calcd for[C 26 H 35 BrO3Si] + 504.5,found 504.5

[0125] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0126] Example 10

[0127] Except for following the following synthesis route and adjusting the parameters according to Table 3, the rest is the same as Example 8. The NMR of the obtained product is as follows.

[0128]

[0129] Compound 4-3 1H-NMR (400MHz, CDCl3): δ = 8.07 (d, 2H, J = 9.2Hz), 7.70-7.67 (m, 4H), 7.55-7.31 (m, 9H), 5.63 (s, 1H), 5.49 (s, 1H), 5.23-5.17 (m, 1H),3.72-3.63(m,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 30 H 35 BrO3Si] + 552.4,found 552.4;

[0130] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0131] Example 11

[0132] Except for following the following synthesis route and adjusting the parameters according to Table 3, the rest is the same as Example 8. The NMR of the obtained product is as follows.

[0133]

[0134] Compound 4-4 1H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),6.27(dd,1H ,10.1Hz,4.4Hz),6.05(dd,1H,9.8Hz,7.6Hz),5.61-5.59(m,2H),(s,1H),5. 47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.67(m,1H)2.61-2.5 6(m,1H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 33 BrO3Si] + 502.5,found 502.5.

[0135] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0136] Example 12

[0137]

[0138] Dissolve (20.0 g, 44.70 mmol) of compound 3A in 100 mL of n-hexane, add (19.24 g, 223.48 mmol) of vinyl acetate and (4.0 g, 0.2 w) of bioenzyme Lipase AK "Amano", and under nitrogen protection, raise the internal temperature to 55-60 ° C. Maintain the internal temperature at 55-60 ° C. and react until the HPLC detection of compound I ee value ≥99%, indicating the reaction is complete. The reaction solution was directly filtered, the filter cake was recovered, and the filtrate was concentrated to obtain a crude product. The crude product was dissolved in 40 mL of acetonitrile, and (7.92 g, 78.23 mmol) of triethylamine (TEA), (0.55 g, 4.47 mmol) of DMAP, and (3.35 g, 33.53 mmol) of succinic anhydride were added. The reaction was allowed to proceed at room temperature until the raw material spots disappeared as observed by TLC. After the reaction was completed, n-heptane and water were added to the reaction solution. The n-heptane phase was collected, and the acetonitrile aqueous phase was extracted with n-heptane. The n-heptane phases were combined and the n-heptane phase was concentrated under reduced pressure at 35-40°C to give 10.4 g of compound 4-1, with a yield of 47.6%.

[0139] To the acetonitrile-water phase was added (3.58 g, 89.40 mmol) of solid sodium hydroxide, and the reaction was carried out at room temperature until the raw material spot disappeared as observed by TLC. The layers were separated, and the acetonitrile phase was collected and concentrated under reduced pressure at 35-40°C to dryness to obtain 9.26 g of compound I with a yield of 46.3% and an ee value of 99.7%.

[0140] Compound 4-1 1 H-NMR (400MHz, CDCl3): δ=7.68-7.65(m,4H),7.45-7.37(m,6H),5.62(s,1H),5.48(s,1H),5.22-5.16(m,1H),3.72-3.63(m ,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),2.03(s,3H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 25 H 33 BrO3Si] + 490.3, found 490.3.

[0141] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0142] Example 13

[0143] Except for following the following synthesis route and adjusting the parameters according to Table 4, the rest is the same as Example 12. The NMR of the obtained product is as follows.

[0144]

[0145] Compound 4-2 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),5.61(s,1H),5.47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.6 7(m,1H)2.61-2.56(m,1H),2.38-2.29(m,2H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.13(t,3H,J=12.0Hz),1.05(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 35 BrO3Si] + 504.5,found 504.5.

[0146] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0147] Example 14

[0148] Except for following the following synthesis route and adjusting the parameters according to Table 4, the rest is the same as Example 12. The NMR of the obtained product is as follows.

[0149]

[0150] Compound 4-3 1 H-NMR (400MHz, CDCl3): δ = 8.07 (d, 2H, J = 9.2Hz), 7.70-7.67 (m, 4H), 7.55-7.31 (m, 9H), 5.63 (s, 1H), 5.49 (s, 1H), 5.23-5.17 (m, 1H),3.72-3.63(m,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 30 H 35 BrO3Si] + 552.4,found 552.4.

[0151] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C23 H 31 BrO2Si] + 448.2,found 448.2.

[0152] Example 15

[0153] Except for following the following synthesis route and adjusting the parameters according to Table 4, the rest is the same as Example 12. The NMR of the obtained product is as follows.

[0154]

[0155] Compound 4-4 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),6.27(dd,1H ,10.1Hz,4.4Hz),6.05(dd,1H,9.8Hz,7.6Hz),5.61-5.59(m,2H),(s,1H),5. 47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.67(m,1H)2.61-2.5 6(m,1H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 33 BrO3Si] + 504.5,found 504.5.

[0156] Compound I 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63–1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0157] Example 16

[0158]

[0159] Compound 3A (20.0 g, 44.69 mmol) was dissolved in 100 mL of dichloromethane (DCM), and triethylamine (13.57 g, 134.07 mmol), DMAP (2.73 g, 22.34 mmol), and acetic anhydride (6.84 g, 67.035 mmol) were added. The mixture was reacted at room temperature under nitrogen until the starting material spot disappeared as observed by TLC, indicating completion of the reaction. 50 mL of saturated brine was added to the reaction solution, stirred, and separated. The organic phase was concentrated to give the crude product as a light yellow oil, which was slurried with 100 mL of n-heptane, filtered, and the filtrate was concentrated to give 21.34 g of compound 3B-1 as a light yellow oil, with a yield of 97.53%.

[0160] H-NMR (400 MHz, CDCl3) of compound 3B-1: δ = 7.68-7.65 (m, 4H), 7.45-7.37 (m, 6H), 5.62 (s, 1H), 5.48 (s, 1H), 5.22-5.16 (m, 1H), 3.72-3.63 (m, 2H), 2.75-2.68 (m, 1H), 2.62-2.57 (m, 1H), 2.03 (s, 3H), 1.81-1.72 (m, 1H), 1.69-1.55 (m, 3H) 1.06 (s, 9H). LC-MS (ESI): m / z calcd for [C 25 H 33 BrO3Si] + 490.3,found 490.3.

[0161] Example 17

[0162]

[0163] Dissolve (10.0 g, 20.43 mmol) of compound 3B-1 in 50 mL of toluene, add (2.17 g, 20.43 mmol) of sodium carbonate, (1.0 g, 0.1 w) of lipase PS-30 from Pseudomonas cepacia, and (1.0 g, 0.1 w) of water, and stir under nitrogen at 35-40 ° C until the HPLC detection of the compound 5ee value is ≥99%, indicating the reaction is complete. The reaction solution was directly filtered, the filter cake was recovered, and the filtrate was washed once with 10 mL of saturated brine. The organic phase was concentrated to obtain a crude product, which was dissolved in 20 mL of acetonitrile, and (3.62 g, 35.75 mmol) of TEA, (0.25 g, 2.043 mmol) of DMAP, and (1.50 g, 15.32 mmol) of maleic anhydride were added. The reaction was allowed to proceed at room temperature until the raw material spots disappeared as observed by TLC. After the reaction was completed, 20 mL of n-heptane and 25 mL of water were added to the reaction solution. The n-heptane phase was collected, and the acetonitrile aqueous phase was extracted with n-heptane. The n-heptane phases were combined and the n-heptane phase was concentrated under reduced pressure at 35-40 ° C to give 4.79 g of compound 4-1, with a yield of 47.9%.

[0164] To the acetonitrile-water phase was added solid sodium hydroxide (1.63 g, 40.86 mmol), and the mixture was reacted at room temperature until the raw material spot disappeared as observed by TLC. The layers were separated, and the acetonitrile phase was collected and concentrated under reduced pressure at 35-40°C to dryness to obtain 4.39 g of compound I with a yield of 48.1% and an ee value of 99.8%.

[0165] Compound 4-1 1 H-NMR (400MHz, CDCl3): δ=7.68-7.65(m,4H),7.45-7.37(m,6H),5.62(s,1H),5.48(s,1H),5.22-5.16(m,1H),3.72-3.63(m ,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),2.03(s,3H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 25 H 33 BrO3Si] + 490.3,found 490.3.

[0166] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0167] Example 18

[0168] Except for following the following synthesis route and adjusting the parameters according to Table 5, the rest is the same as Example 16. The NMR of the obtained product is as follows.

[0169]

[0170] Compound 3B-2 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),5.61(s,1H),5.47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2. 74-2.67(m,1H)2.61-2.56(m,1H),2.38-2.29(m,2H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.13(t,3H,J=12.0Hz).LC-MS(ESI):m / z calcd for[C 26 H 35 BrO3Si] + 504.5,found 504.5.

[0171] Example 19

[0172] Except for following the following synthesis route and adjusting the parameters according to Table 6, the rest is the same as Example 17. The NMR of the obtained product is as follows.

[0173]

[0174] Compound 4-2 1H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),5.61(s,1H),5.47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2. 74-2.67(m,1H)2.61-2.56(m,1H),2.38-2.29(m,2H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.13(t,3H,J=12.0Hz).LC-MS(ESI):m / z calcd for[C 26 H 35 BrO3Si] + 504.5,found 504.5.

[0175] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63–1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0176] Example 20

[0177] Except for following the following synthesis route and adjusting the parameters according to Table 5, the rest is the same as Example 16. The NMR of the obtained product is as follows.

[0178]

[0179] Compound 3B-3 1H-NMR (400MHz, CDCl3): δ = 8.07 (d, 2H, J = 9.2Hz), 7.70-7.67 (m, 4H), 7.55-7.31 (m, 9H), 5.63 (s, 1H), 5.49 (s, 1H), 5.23-5.17 (m, 1H),3.72-3.63(m,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 30 H 35 BrO3Si] + 552.4,found 552.4.

[0180] Example 21

[0181] Except for following the following synthesis route and adjusting the parameters according to Table 6, the rest is the same as Example 17. The NMR of the obtained product is as follows.

[0182]

[0183] Compound 4-3 1 H-NMR (400MHz, CDCl3): δ = 8.07 (d, 2H, J = 9.2Hz), 7.70-7.67 (m, 4H), 7.55-7.31 (m, 9H), 5.63 (s, 1H), 5.49 (s, 1H), 5.23-5.17 (m, 1H),3.72-3.63(m,2H),2.75-2.68(m,1H),2.62-2.57(m,1H),1.81-1.72(m,1H),1.69-1.55(m,3H)1.06(s,9H).LC-MS(ESI):m / z calcd for[C 30 H 35 BrO3Si] + 552.4,found 552.4.

[0184] Compound Ⅰ 1H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63–1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2

[0185] Example 22

[0186] Except for following the following synthesis route and adjusting the parameters according to Table 5, the rest is the same as Example 16. The NMR of the obtained product is as follows.

[0187]

[0188] Compound 3B-4 1 H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),6.27(dd,1H ,10.1Hz,4.4Hz),6.05(dd,1H,9.8Hz,7.6Hz),5.61-5.59(m,2H),(s,1H),5. 47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.67(m,1H)2.61-2.5 6(m,1H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 33 BrO3Si] + 502.5,found 502.5.

[0189] Example 23

[0190] Except for following the following synthesis route and adjusting the parameters according to Table 6, the rest is the same as Example 17. The NMR of the obtained product is as follows.

[0191]

[0192] Compound 4-4 1H-NMR (400MHz, CDCl3): δ=7.67-7.64(m,4H),7.45-7.37(m,6H),6.27(dd,1H ,10.1Hz,4.4Hz),6.05(dd,1H,9.8Hz,7.6Hz),5.61-5.59(m,2H),(s,1H),5. 47(s,1H),5.21-5.15(m,1H),3.71-3.62(m,2H),2.74-2.67(m,1H)2.61-2.5 6(m,1H),1.80-1.72(m,1H),1.68-1.54(m,3H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 26 H 33 BrO3Si] + 502.5,found 502.5.

[0193] Compound Ⅰ 1 H-NMR (400MHz, CDCl3): δ=7.70-7.67(m,4H),7.46-7.38(m,6H),5.70(s,1H),5.54(s,1H),4.01-3.99(m,1H),3.7 4-3.71(m,2H),2.62-2.52(m,2H),2.37(s,1H)1.76-1.65(m,3H),1.63-1.53(m,1H),1.07(s,9H).LC-MS(ESI):m / z calcd for[C 23 H 31 BrO2Si] + 448.2,found 448.2.

[0194] The relevant parameters in the above-mentioned Examples 1 to 23 are shown in Tables 1 to 6.

[0195] Table 1

[0196]

[0197] Table 2

[0198]

[0199] Table 3

[0200]

[0201]

[0202] Table 4

[0203]

[0204] Table 5

[0205]

[0206]

[0207] Table 6

[0208]

Claims

1. A method for preparing a chiral compound I by an enzymatic method, comprising the following steps: Method 1: The first method uses the compound shown in Formula 3A as a raw material, undergoes an acylation reaction with an acylating agent under the action of a biological enzyme A to obtain compound 4 and compound 1, and selectively separates the mixture of compound 4 and compound 1; Method 2: The second method uses the compound shown in Formula 3B as a raw material, hydrolyzes it under the action of biological enzyme B and alkali to obtain the compound 4 and the compound 1, and selectively separates the mixture of the compound 4 and the compound 1; in, R1 is C1-C substituted or unsubstituted by Ra 12 Straight chain or branched chain acyl, benzoyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 A heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl, more preferably acetyl, propionyl, butyryl, benzoyl or acryloyl; The biological enzyme A is a lipase or an esterase, and the biological enzyme A is selected from lipase AK, lipase from Pseudomonas fluorescens, lipase B from Candida antarctica, Candida antarctica lipase B immobilized on acrylic resin, lipase AS, lipase PS, lipase from thermophilic mold, lipase from Candida, lipase AYS, triacylglycerol lipase, lipase from Mucor miehei or lipase from Rhizopus oryzae, Candida antarctica lipase B immobilized on Immobead 150, or recombinant Aspergillus oryzae; the biological enzyme A is preferably lipase AK, lipase from Pseudomonas fluorescens or Candida antarctica lipase B immobilized on acrylic resin Novozym 435; The biological enzyme B is a lipase, an esterase or a hydrolase, and the biological enzyme B is selected from lipase TL, lipase PS-30 from Pseudomonas cepacia, lipase QLM, lipase from Thermomyces lanuginosus, lipase P2 from Pseudomonas cepacia, lipase PS from Pseudomonas stutzeri, lipase RS from Koji enzyme, lipase PS from Pseudomonas cepacia, lipase AN from Aspergillus niger, lipase A from Achromatosis, lipase AS1 from Alcaligenes, lipase AS2 from Alcaligenes, lipase C2 from Candida cylindrica, lipase C1 from Candida cylindrica, lipase TL IM, lipase TL 100L, Candida antarctica lipase B, CHIRAZYME E-1 pig liver esterase, lipase from Pseudomonas L-6, Candida antarctica lipase A, Candida rugosa lipase L-3 or pancreatic lipase, the biological enzyme B is preferably lipase TL or lipase PS-30 from Pseudomonas cepacia.

2. The method according to claim 1, wherein: The acylating agent of the method 1 is selected from vinyl ester or isopropenyl ester, wherein the vinyl ester is selected from C1-C 12 Straight chain or branched chain vinyl ester, vinyl benzoate, C3-C6 straight chain or branched chain vinyl ester substituted or unsubstituted by Rc; the isopropenyl ester is selected from C1-C6 substituted or unsubstituted by Rc 12 isopropenyl benzoate, isopropenyl benzoate, isopropenyl alkene acid substituted or unsubstituted by Rc; the substituent Rc of each group is independently selected from C1-C6 straight chain or branched alkyl, C1-C6 straight chain or branched alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 Heterocyclic aromatic group, wherein the heteroatom of the heterocyclic aromatic group is selected from O, N or S; The acylating agent is preferably vinyl acetate, isopropylene acetate, vinyl propionate, isopropylene propionate, vinyl butyrate, isopropylene butyrate, vinyl isobutylate, isopropylene isobutylate, vinyl 2-methylbutyrate, isopropylene 2-methylbutyrate, vinyl 3-methylbutyrate, isopropylene 3-methylbutyrate, vinyl pivalate, isopropylene pivalate, vinyl 2-methylvalerate, isopropylene 2-methylvalerate, vinyl 3-methylvalerate, isopropylene 3-methylvalerate, 4-methylpentylene, isopropylene 4-methylpentylene, vinyl hexanoate, isopropylene hexanoate, vinyl laurate, isopropylene laurate, vinyl benzoate, isopropylene benzoate, vinyl acrylate or isopropylene acrylate, more preferably vinyl acetate, isopropylene acetate, vinyl propionate, isopropylene propionate, vinyl butyrate, isopropylene butyrate, vinyl benzoate, isopropylene benzoate, vinyl acrylate or isopropylene acrylate.

3. The method according to claim 1, wherein: The acylation reaction of the method 1 is carried out in an organic solvent A, wherein the organic solvent A is selected from one or any combination of alkanes, aromatic hydrocarbons, chloroalkanes, nitriles or ether solvents; the organic solvent A is preferably one or any combination of petroleum ether, ethyl ether, methyl tert-butyl ether, dichloromethane, n-hexane, cyclohexane, n-pentane, cyclopentane, n-heptane, toluene or acetonitrile; more preferably one or any combination of n-hexane or n-heptane; And / or in the method 1, the mass volume ratio of compound 3A to the organic solvent A is 1 g:1-15 mL, more preferably 1 g:5-8 mL; and / or the acylation reaction temperature in the method 1 is 30-80° C., preferably 55-60° C.; And / or in the method 1, the mass ratio of compound 3A to the biological enzyme A is 1:0.005-0.3, preferably 1:0.01-0.3, more preferably 1:0.05-0.2; And / or in the method 1, the molar ratio of compound 3A to the acylating agent is 1:1-20, preferably 1:2-10, and more preferably 1:3-6.

4. The method according to claim 1, wherein: The hydrolysis reaction of the second method is carried out in water and an organic solvent B, wherein the organic solvent B is selected from one or any combination of alkanes, aromatic hydrocarbons, chloroalkanes, nitrile solvents or ether solvents; the organic solvent B is preferably selected from one or any combination of toluene, xylene, methyl tert-butyl ether or acetonitrile; and / or the base is selected from an organic base or an inorganic base, the organic base is selected from one or any combination of diethylamine, triethylamine, diisopropylamine, morpholine, N-methylmorpholine, piperazine or N-methylpiperazine; the inorganic base is selected from one or any combination of alkali metal hydroxides, carbonates or bicarbonates or alkaline earth metal hydroxides; the base is preferably one or any combination of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium bicarbonate, sodium bicarbonate or potassium carbonate; most preferably one or any combination of sodium carbonate or potassium carbonate; And / or in method 2, the mass ratio of compound 3B to the biological enzyme B is 1:0.005-0.3, preferably 1:0.01-0.3, more preferably 1:0.05-0.2; and / or in method 2, the molar ratio of compound 3B to the base is 1:1-10, preferably 1:1-8, more preferably 1:1-4; And / or in method 2, the mass volume ratio of compound 3B to the organic solvent B is 1 g:1-15 mL, more preferably 1 g:3-8 mL. And / or the hydrolysis reaction temperature in method 2 is 30-80°C, preferably 35-40°C.

5. The method according to claim 1, wherein The method for selectively separating the mixture of compound 4 and compound 1 comprises: 1) separating the mixture of compound 4 and compound 1 by column chromatography to obtain compound 1; or 2) Step a: In the presence of a catalyst and an organic base, compound I in the mixture of compound 4 and compound I selectively undergoes an esterification reaction with an acid anhydride to separate compound 4 and compound 5; Step b: Compound 5 is hydrolyzed to obtain compound I, as shown in the following reaction formula: Wherein, R1 is C1-C substituted or unsubstituted by Ra 12 Straight chain or branched chain acyl, benzoyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 Heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl; R2 is selected from 6. A method for preparing a chiral compound I, comprising the step of separating a mixture of compound 4 and compound I, wherein the separation method comprises: 3) separating the mixture of compound 4 and compound 1 by column chromatography to obtain compound 1; or 4) Step a: In the presence of a catalyst and an organic base, compound I in the mixture of compound 4 and compound I selectively undergoes an esterification reaction with an acid anhydride to separate compound 4 and compound 5; Step b: Compound 5 is hydrolyzed to obtain compound I, as shown in the following reaction formula: Wherein, R1 is C1-C substituted or unsubstituted by Ra 12 Straight chain or branched chain acyl, benzoyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 Heterocyclic aromatic group, wherein the heteroatoms on the heterocyclic aromatic group are selected from O, N or S; R1 is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl; R2 is selected from 7. The method according to claim 5 or 6, characterized in that: The column chromatography separation method uses petroleum ether:ethyl acetate with a volume ratio of 20:1 to 5:1 as an eluent for silica gel column chromatography separation.

8. The method according to claim 5 or 6, characterized in that: In step a, the catalyst is selected from 4-dimethylaminopyridine; and / or the molar ratio of compound I to the catalyst in step a is 1:0.1-0.5, preferably 1:0.2-0.3; and / or the organic base in step a is selected from one or any combination of diethylamine, triethylamine, diisopropylamine, pyridine, α-picoline, 1,2-lutidine, 4-hydroxy-2-picoline, γ-collidine, quinoline or dimethylquinoline, preferably selected from one or any combination of triethylamine, diisopropylamine, pyridine or α-picoline; and / or the molar ratio of compound I to the organic base in step a is 1:1-10, preferably 1:1-5, more preferably 1:3-5; the temperature of the esterification reaction is 0-50° C., preferably 10-30° C.; And / or the anhydride in step a is selected from The molar ratio of the compound I to the acid anhydride is 1:1 to 10, preferably 1:1 to 5, more preferably 1:1.1 to 1.8; And / or the esterification reaction in step a is carried out in a reaction solvent C, wherein the reaction solvent C is selected from one or any combination of aromatic hydrocarbons, chlorinated alkanes, nitrile solvents or ether solvents; the reaction solvent C is preferably selected from one or any combination of toluene, xylene, methyl tert-butyl ether or acetonitrile; And / or the hydrolysis in step b is carried out in water and an organic solvent D, wherein the organic solvent D is selected from the reaction solvent C in step a. Preferably, the hydrolysis is carried out in water and acetonitrile; the reaction temperature is preferably room temperature; And / or the hydrolysis in step b is carried out in an inorganic base, wherein the inorganic base is selected from one or any combination of alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates or alkaline earth metal hydroxides; preferably selected from one or any combination of lithium hydroxide, sodium hydroxide, potassium hydroxide or barium hydroxide; more preferably selected from one or any combination of sodium hydroxide or potassium hydroxide.

9. An intermediate compound having the following structure: * represents chiral carbon; R is C1-C substituted or unsubstituted by Ra 12 Straight chain or branched chain acyl, C3-C6 straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, The substituents Ra of each group are independently selected from C1-C6 straight or branched alkyl, C1-C6 straight or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C1-C6 amide, C3-C6 cycloalkyl, C1-C6 sulfanyl, C1-C6 amide, C3-C6 cycloalkyl, phenyl or C3-C 18 Heterocyclic aromatic group, wherein the heteroatom of the heterocyclic aromatic group is selected from O, N or S; Preferably, when the chiral carbon represented by * is in S configuration, the structure is: in, R1 is C1-C substituted or unsubstituted by Ra 12 A straight chain or branched chain acyl group, a C3-C6 straight chain or branched chain alkenoyl group which is substituted or unsubstituted by Ra, wherein the substituent Ra of each group is independently selected from C1-C6 straight chain or branched chain alkyl, C1-C6 straight chain or branched chain alkoxy, hydroxyl, amino, halogen, nitro, cyano, C1-C6 amide group, C3-C6 cycloalkyl group, C1-C6 sulfanyl group, C1-C6 amide group, C3-C6 cycloalkyl group, phenyl group or C3-C 18 A heterocyclic aromatic group, wherein the heteroatom on the heterocyclic aromatic group is selected from O, N or S; R1 is preferably propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl or acryloyl; The intermediate compound is preferably the following compound: When the chiral carbon represented by * is in R configuration, the structure is: Wherein, R2 is selected from The intermediate compound is preferably the following compound:

10. A method for preparing an eribulin drug, characterized in that: The method comprises the method according to any one of claims 1 to 5 or the method according to any one of claims 6 to 8.