CN119585437A

CN119585437A - A preparation method of eribulin intermediate

Info

Publication number: CN119585437A
Application number: CN202280098435.7A
Authority: CN
Inventors: 吴哲; 孙敏; 丁福斗; 蔡伶俐; 张宪恕; 王子坤; 高强; 郑保富
Original assignee: Shanghai Haoyuan Chemexpress Co ltd
Current assignee: Shanghai Haoyuan Chemexpress Co ltd
Priority date: 2022-07-29
Filing date: 2022-09-19
Publication date: 2025-03-07
Also published as: CN115323011A; WO2024021261A1

Abstract

The preparation method comprises the following steps of starting from a compound 3A or a compound 3B, selectively acylating by using biological enzyme A or selectively hydrolyzing by using biological enzyme B, reacting hydroxyl of a required configuration with anhydride under the action of organic base and a catalyst to obtain a compound 5, increasing the water solubility of an intermediate product, realizing separation of two configurations through extraction separation, enabling an ee value to reach more than 99%, and being simple in preparation method operation, high in conversion rate, good in selectivity, low in cost and beneficial to industrial scale-up production.

Description

Eribulin Process for the preparation of intermediates

The present application claims priority from the chinese patent office, application number 202210904052.6, entitled "method for preparing eribulin intermediate", filed on 7/29/2022, the entire contents of which are incorporated herein by reference.

Technical Field

The invention belongs to the field of pharmaceutical chemistry, and particularly relates to a preparation method of eribulin intermediates.

Background

Eribulin mesylate (Eribulin Mesylate) is a synthetic analog of halichondrin B, having the biologically active macrocyclic moiety of halichondrin B. Halichondrin B is a polyether macrolide that exhibits potent anticancer effects both in cells and animal models. Eribulin mesylate inhibits cell tubulin mitosis, resulting in irreversible cell cycle G2/M phase arrest and mitotic spindle cleavage, apoptosis after long-term cell mitosis arrest, and inhibited cell proliferation. Eribulin mesylate injection was developed by Eisai inc, approved by the U.S. FDA as marketed in the united states in 2010 at 11, under the trade name Halaven, for metastatic breast cancer patients who had previously received at least two metastatic cancer treatment regimens, and based on the results of subset analysis, eribulin mesylate was shown to be positively and effectively useful for the treatment of triple negative metastatic breast cancer, a malignant breast cancer, with a often poor prognosis. In many countries, eribulin mesylate has been considered as an even later drug therapy for the treatment of metastatic breast cancer, however, this drug is the only chemotherapeutic agent that is effective in improving patient survival during treatment. Eribulin mesylate is the only drug with good clinical and market prospects in the field at present.

The early intermediate structure of eribulin is shown in the following formula I:

the prior art synthesis of the compounds of formula I is the following method:

the process route of the early intermediate I of the eribulin bulk drug synthesized by the raw materials of the original grinding manufacturer is as follows:

wherein, TBDPS is tert-butyl diphenyl silicon base.

The hydroxyl carbon protected by the tosyl of the compound I has chirality, a racemate is obtained in the synthesis process, and literature reports (Synlett (2013), 24 (3), 327-332, WO2005118565 and the like) are used for preparing and separating the compound shown in the formula 3 through a chiral Simulated Moving Bed (SMB) to obtain a single configuration, so that the preparation efficiency is low, the cost is high, and the large-scale production is not facilitated. In addition, literature (org. Lett., vol.10, no.14,2008) reports that a single configuration of product is obtained under catalysis of chiral ligands with metallic chromium, but at high cost.

Disclosure of Invention

The invention aims to solve the technical problem of providing a method for preparing a compound shown in a formula I, which is completely different from the prior art, and the method is mild in reaction conditions, environment-friendly, novel in route, simple in post-treatment and purification, and the prepared compound shown in the formula I is high in purity, simple in preparation method operation, high in conversion rate, good in selectivity, low in cost and beneficial to industrial scale-up production, and the compound shown in the formula I can be applied to preparation of eribulin medicines.

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

The method comprises the following steps:

The method comprises the steps of firstly, taking a compound shown as a formula 3A as a raw material, carrying out an acylation reaction with an acylating reagent under the action of a biological enzyme A to obtain a compound 4 and a compound I, and selectively separating a mixture of the compound 4 and the compound I;

The second method is as follows:

The second method is that a compound shown as a formula 3B is taken as a raw material, and is subjected to hydrolysis reaction under the action of biological enzyme B and alkali to obtain a compound 4 and a compound I, and a mixture of the compound 4 and the compound I is selectively separated;

wherein R ₁ is C ₁-C ₁₂ straight or branched acyl substituted or unsubstituted by Ra, benzoyl, C ₃-C ₆ straight or branched alkenoyl substituted or unsubstituted by Ra, the substituents Ra of each group are each independently selected from C ₁-C ₆ straight or branched alkyl, C ₁-C ₆ straight or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, C ₁-C ₆ sulfanyl, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, phenyl or C ₃-C ₁₈ heterocycloaryl, the heteroatoms on the heterocycloaryl being selected from O, N or S, R ₁ is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutanoyl, 3-methylbutanoyl, pivaloyl, 2-methylpentanoyl, 3-methylpentanoyl, 4-methylpentanoyl, hexanoyl, lauroyl, benzoyl or acryloyl, more preferably acetyl, propionyl, butyryl, benzoyl or acryloyl.

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

As a further development of the invention, the biological enzymes B of the second process are lipases, esterases or hydrolases, for example, lipase TL, lipase PS-30 from Pseudomonas cepacia, lipase QLM, lipase P2 from Pseudomonas lanuginosa (Thermomyceslanuginosus), lipase PS from Pseudomonas cepacia (Pseudomonas cepacia), lipase RS from Pseudomonas stutzeri (Pseudomonas stutzeri), lipase PS from Pseudomonas cepacia, lipase AN from Aspergillus niger (Aspergillus niger), lipase AS1 from Achromobacter sp, lipase AS2 from Alcaligenes Alcaligenes, lipase C2 from Candida cylindracea (CANDIDA CYLINDRACEA), lipase C1 from Candida cylindracea, lipase lipozym TL IM, lipase lipozym TL L, candida antarctica (CANDIDA ANTARCTICA), lipase B (CAE-CHIRAZYME) or Candida albicans lipase A from Candida glabra (Candida glabra), lipase A-3.

As a further improvement of the present invention, the acylating agent of process one is selected from vinyl esters of C ₁-C ₁₂ linear or branched vinyl acids substituted or unsubstituted with Rc, vinyl benzoate, C ₃-C ₆ linear or branched vinyl acrylates substituted or unsubstituted with Rc, or isopropenyl esters selected from C ₁-C ₁₂ linear or branched isopropenyl acids substituted or unsubstituted with Rc, isopropenyl benzoate, C ₃-C ₆ linear or branched isopropenyl alkenoates substituted or unsubstituted with Rc. The substituents Rc of each group are independently selected from C ₁-C ₆ straight or branched alkyl, C ₁-C ₆ straight or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, C ₁-C ₆ sulfanyl, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, phenyl, or C ₃-C ₁₈ heterocyclic aromatic groups, the heteroatoms on the heterocyclic aromatic groups being selected from O, N or S.

As a further improvement of the present invention, the acylating agent of process one is preferably vinyl acetate, isopropenyl acetate, vinyl propionate, isopropenyl propionate, vinyl butyrate, isopropenyl butyrate, vinyl isobutyrate, isopropenyl isobutyrate, vinyl 2-methylbutanoate, vinyl 3-methylbutanoate, isopropenyl 3-methylbutanoate, vinyl pivalate, isopropenyl pivalate, vinyl 2-methylpentanoate, isopropenyl 2-methylpentanoate, vinyl 3-methylpentanoate, isopropenyl 3-methylpentanoate, 4-methylpentanyl vinyl 4-methylpentanoate, vinyl caproate, isopropenyl caproate, vinyl laurate, isopropenyl benzoate, vinyl acrylate or isopropenyl acrylate, more preferably vinyl acetate, isopropenyl acetate, vinyl propionate, isopropenyl butyrate, vinyl benzoate, isopropenyl benzoate or isopropenyl acrylate.

The biological enzyme A provided by the invention can be used for selectively acylating the alcohol of the formula 3A by using one biological enzyme A to generate the acylated compound of a single isomer of the formula 4, and the compound of the formula I can be conveniently separated from the compound of the formula 4. The acylation reaction may be carried out in an organic solvent. The enantiomeric excess of the product of formula I is preferably at least 96% ee, more preferably at least 99% ee. The enzyme can be immobilized on a carrier to facilitate recovery of the enzyme and ease post-reaction treatment, and has the characteristics of high selectivity, good stability, high enzyme activity and low cost.

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

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

As a further improvement of the invention, in the first method, the acylation reaction temperature is 30-80 ℃, preferably 55-60 ℃, and the activity of the enzyme is good, the reaction rate is high and the efficiency is high in the temperature range.

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

As a further improvement of the invention, in the method I, the molar ratio of the compound 3A to the acylating agent is 1:1-20, preferably 1:2-10, more preferably 1:3-6, and the acylating agent and the biological enzyme are used in combination, so that the S-configuration compound in the racemized compound 3A can be selectively subjected to the acylation reaction to obtain the compound 4, the reaction yield is high, and the isomer purity is good.

As a further improvement of the present invention, the enantioselective acylation according to the invention gives products comprising a mixture of the compounds of the formula I in R-form and the compounds of the formula 4 in S-form. Likewise, enantioselective enzymatic hydrolysis may result in a mixture comprising the compound of formula I in R-form and the compound of formula 4 in S-form. The optical purity of the compounds of formula I obtained by the optical resolution process of the 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.

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

As a further improvement of the present invention, the base is selected from an organic base selected from one of diethylamine, triethylamine (TEA), diisopropylamine, morpholine, N-methylmorpholine, piperazine or N-methylpiperazine or any combination thereof, or an inorganic base comprising one of alkali metal hydroxide, carbonate or bicarbonate or alkaline earth metal hydroxide or any combination thereof, for example. Preferably, the base is one or any combination of an alkali metal hydroxide, an alkali metal carbonate or an alkali metal bicarbonate, 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, and most preferably one or any combination of sodium carbonate or potassium carbonate. The alkali and the biological enzyme B are combined for use, R configuration reaction in the racemization compound 3B can be selectively hydrolyzed to obtain the compound I, the reaction yield is high, and the isomer purity is good.

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

As a further improvement of the invention, in the method II, the molar ratio of the compound 3B to the alkali is 1:1-10, preferably 1:1-8, and more preferably 1:1-4.

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

As a further improvement of the method, the hydrolysis reaction temperature is 30-80 ℃, preferably 35-40 ℃, and the activity of the enzyme is good, the reaction rate is high and the efficiency is high in the temperature range.

As a further improvement of the present invention, the method for selectively separating a mixture of compound 4 and compound I, comprises:

1) Separating the mixture of compound 4 and compound I by column chromatography to give compound I, or

2) Step a, under the action of a catalyst and an organic base, the compound I in the mixture of the compound 4 and the compound I selectively reacts with anhydride in an esterification reaction, the compound 4 and the compound 5 are separated, and the compound 5 is hydrolyzed to obtain the compound I, wherein the reaction formula is as follows:

wherein R ₁ is C ₁-C ₁₂ linear or branched acyl substituted or unsubstituted by Ra, benzoyl, C ₃-C ₆ linear or branched alkenoyl substituted or unsubstituted by Ra, the substituents Ra of each group are each independently selected from C ₁-C ₆ linear or branched alkyl, C ₁-C ₆ linear or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, C ₁-C ₆ sulfanyl, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, phenyl or C ₃-C ₁₈ heterocycloaryl, the heteroatoms on the heterocycloaryl are selected from O, N or S, R ₁ is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylpentanoyl, 3-methylpentanoyl, 4-methylpentanoyl, hexanoyl, lauroyl, benzoyl or acryloyl, R ₂ is selected from

As a further improvement of the invention, the separation condition of the column chromatography method is that petroleum ether and ethyl acetate with the volume ratio of 20:1-5:1 are used as eluent for silica gel column chromatography separation.

As a further development of the invention, the catalyst in step a is selected from the group consisting of 4-Dimethylaminopyridine (DMAP).

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

As a further improvement of the invention, the organic base in the step a is selected from one or any combination of diethylamine, triethylamine, diisopropylamine, pyridine, alpha-methylpyridine, 1, 2-dimethylpyridine, 4-hydroxy-2-methylpyridine, gamma-trimethylpyridine, quinoline or dimethylquinoline, the organic base in the step a is preferably selected from one or any combination of triethylamine, diisopropylamine, pyridine or alpha-methylpyridine, the molar ratio of the compound I to the organic base in the step a is 1:1-10, preferably 1:1-5, more preferably 1:3-5, and the esterification reaction temperature is 0-50 ℃, preferably 10-30 ℃.

As a further development of the invention, the anhydride in step a is selected fromThe molar ratio of the compound I to the anhydride is 1:1-10, preferably 1:1-5, and more preferably 1:1.1-1.8.

As a further improvement of the present invention, the esterification reaction in the step a is carried out in a reaction solvent C which comprises one or any combination of aromatic hydrocarbon, chlorinated alkane, nitrile solvent or ether solvent, for example, one or any combination of aromatic hydrocarbon, toluene, xylene or chlorobenzene, chlorinated alkane, nitrile, ether is selected from one or any combination of acetonitrile, propionitrile or benzonitrile, ether is selected from one or any combination of petroleum ether, tetrahydrofuran, 1, 4-dioxane, diethyl ether, diisopropyl ether or methyl tertiary butyl ether, and reaction solvent C is preferably selected from one or any combination of toluene, xylene, methyl tertiary butyl ether or acetonitrile.

As a further improvement of the present invention, the step a separation includes a conventional separation step such as liquid separation, extraction, water washing or concentration, etc., and the present invention is not particularly limited to the liquid separation or the solvent for extraction, and one or any combination of alkane, chloroalkane or ether solvents may be used, for example, one or any combination of alkane selected from n-hexane, cyclohexane, n-pentane, cyclopentane or n-heptane, chloroalkane selected from one or any combination of dichloromethane or chloroform, ether selected from one or any combination of petroleum ether, tetrahydrofuran, 1, 4-dioxane, diethyl ether, diisopropyl ether or methyl tert-butyl ether (MTBE).

As a further development of the invention, the hydrolysis in step b is carried out in water and an organic solvent D, which is selected from the group of organic solvents which do not adversely affect, preferably from the group of reaction solvents C in step a described above, preferably in water and acetonitrile, and the reaction temperature is preferably room temperature.

As a further improvement of the invention, the hydrolysis of step b is performed in an inorganic base selected from one of alkali metal hydroxide, alkali metal carbonate, alkali metal bicarbonate or alkaline earth metal hydroxide or any combination thereof. 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 alkali is preferably selected from one or any combination of lithium hydroxide, sodium hydroxide, potassium hydroxide or barium hydroxide, and more preferably one or any combination of sodium hydroxide or potassium hydroxide.

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

In a second aspect, the present invention provides a process for preparing chiral compound I comprising the step of separating a mixture of compound 4 and compound I, the separation process comprising:

3) Separating the mixture of compound 4 and compound I by column chromatography to give compound I, or

4) Step a, under the action of a catalyst and an organic base, the compound I in the mixture of the compound 4 and the compound I selectively reacts with anhydride in an esterification reaction, and the compound 4 and the compound 5 are separated, and step b, the compound 5 is hydrolyzed to obtain the compound I, wherein the reaction formula is as follows:

Wherein R ₁ is C ₁-C ₁₂ linear or branched acyl which is substituted or unsubstituted, benzoyl, C ₃-C ₆ linear or branched alkenoyl which is substituted or unsubstituted by Ra, the substituents Ra of the individual groups are each independently selected from C ₁-C ₆ linear or branched alkyl, C ₁-C ₆ linear or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, C ₁-C ₆ sulfanyl, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, phenyl or C ₃-C ₁₈ heterocycloaryl, the heteroatoms on the heterocycloaryl being selected from O, N or S, R ₁ is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutanoyl, 3-methylbutanoyl, pivaloyl, 2-methylpentanoyl, 3-methylpentanoyl, 4-methylpentanoyl, hexanoyl, lauroyl, benzoyl or acryloyl, R ₂ is selected from

As a further improvement of the present invention, the reaction conditions of each step of the compound I of the second aspect can be referred to as the parameters of the reaction conditions of each step in the first aspect of the present invention, and when continuously feeding, no matter whether the compound 3A is acylated in the biological enzyme A or the compound 3B is hydrolyzed in the biological enzyme B to obtain a mixture of the compound I and the compound 4, the accurate feeding can be detected according to the theoretical yield of 50% or the reference High Performance Liquid Chromatography (HPLC), and the reaction of the next step with the anhydride step a is not influenced.

As a further development of the application, compound 4 can be converted directly to compound I by hydrolysis, by the method described in Synlett (2013), 24 (3), 327-332 (incorporated herein by reference in its entirety).

As a further improvement of the invention, the preparation of the mixture of the compound 4 and the compound I comprises the step of carrying out selective acylation or hydrolysis reaction on the compound 3A or the compound 3B under the action of biological enzyme A and biological enzyme B to obtain the mixture of the compound 4 and the compound I. The reaction formula is as follows:

as a further improvement of the present invention, the reaction conditions in the preparation of the mixture of compound 4 and compound I of the second aspect may be referred to the reaction conditions of the steps in the first aspect of the present invention described above.

In a third aspect, the present invention provides a key intermediate for the preparation of compound I. In certain embodiments, key intermediate compound C is represented as follows:

* R is selected from the group consisting of a C ₁-C ₁₂ linear or branched acyl group substituted or unsubstituted by Ra, a C ₃-C ₆ linear or branched alkenoyl group substituted or unsubstituted by Ra,

Wherein the substituents Ra of each group are each independently selected from C ₁-C ₆ straight or branched chain alkyl, C ₁-C ₆ straight or branched chain alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, C ₁-C ₆ sulfanyl, C ₁-C ₆ amido, C ₃-C ₆ cycloalkyl, phenyl or C ₃-C ₁₈ heterocyclic aromatic groups, the heteroatoms on the heterocyclic aromatic groups being selected from O, N or S.

Preferably, when the chiral carbon represented is in S configuration, the structure is:

wherein R ₁ is a C ₁-C ₁₂ linear or branched acyl group substituted or unsubstituted by Ra, a C ₃-C ₆ linear or branched alkenoyl group substituted or unsubstituted by Ra, the substituents Ra of each group are each independently selected from C ₁-C ₆ linear or branched alkyl group, C ₁-C ₆ linear or branched alkoxy group, hydroxy group, amino group, halogen, nitro group, cyano group, C ₁-C ₆ amide group, C ₃-C ₆ cycloalkyl group, C ₁-C ₆ sulfanyl group, C ₁-C ₆ amide group, C ₃-C ₆ cycloalkyl group, phenyl group or C ₃-C ₁₈ heterocyclic aromatic group having a heteroatom selected from O, N or S, R ₁ is preferably propionyl group, butyryl group, isobutyryl group, 2-methylbutyryl group, 3-methylbutyryl group, pivaloyl group, 2-methylpentanoyl group, 3-methylpentanoyl group, 4-methylpentanoyl group, hexanoyl group, lauroyl group or acryloyl group.

As a further improvement of the present invention, the key intermediate compound is selected from, without limitation, the following compounds:

When chiral carbon is represented as R configuration, the structure is:

Wherein R ₂ is selected from

in a third aspect, the present application provides a method of preparing an eribulin medicament comprising the method provided in the first aspect of the application or the method provided in the second aspect of the application.

Compared with the prior art, the invention provides a novel method for preparing the compound shown in the formula I, which has the advantages of mild reaction conditions, environment friendliness, novel route, simple post-treatment and purification, high purity of the prepared compound shown in the formula I, simple operation, high conversion rate, good selectivity, low cost and contribution to industrial scale-up production, the compound shown in the formula I can be applied to preparing eribulin medicines, and the method for preparing the compound I has the advantages that:

1) The racemization compound 3 (including 3A or 3B) does not need to be subjected to high-cost SMB operation or the catalysis of chiral ligand and metal chromium, and the compound 3 can be separated by selective separation of the screened biological enzyme (A or B) and conventional filtration operation only by column chromatography purification means.

2) The biological enzyme screened by the invention has the characteristics of high selectivity, good stability, high enzyme activity, recycling and low cost.

3) The invention realizes the resolution of the raceme compound by the selective acylation of biological enzyme and discovers that the yield of the compound I is more than 93% and the ee value is more than 99%.

4) The invention adopts biological enzyme resolution method to protect the unwanted configuration selectively, reduces the polarity of the intermediate product, uses acid anhydride to react the hydroxyl of the needed configuration with the acid anhydride under the action of organic base and catalyst, increases the water solubility of the intermediate product, adopts small polar solvent to extract and remove the unwanted configuration (the product protected by the acyl), can realize the separation of the two configurations without column chromatography purification means, and has ee value reaching more than 99 percent.

Detailed Description

To facilitate understanding of the present disclosure by those skilled in the art, the technical scheme of the present disclosure will be further described with reference to specific examples, but the following description is not intended to limit the scope and spirit of the present disclosure as claimed in the claims. The starting materials, reagents or solvents used in the present invention are commercially available without any particular description, and experimental methods for specific conditions not specifically described are carried out under conditions conventional in the art.

In the present invention, the yield refers to the mole percentage of the actual yield to the theoretical yield of a certain product. "w" is a mass ratio, for example, 0.2w of the bio-enzyme means that the mass ratio of the bio-enzyme to the raw material (compound 3A/compound 3B) is 0.2.

Example 1

Compound 3A (20.0 g,44.70 mmol) was dissolved in 120mL of n-heptane, vinyl acetate (15.4 g,223.48 mmol) and biological enzyme (enzyme) Lipase AK "Amano" (4.0 g,0.2 w) were added, the internal temperature was raised to 55-60℃under nitrogen protection, and the internal temperature was kept at 55-60℃until the ee value of compound I detected by HPLC was not less than 99% after the reaction. The reaction solution was directly filtered, the filter cake was recovered, the filtrate was concentrated to obtain a crude product, which was separated by silica gel column chromatography, distilled under reduced pressure and concentrated to dryness to obtain 10.5g of Compound 4-1 in a yield of 48.0% and 9.44g of Compound I in a yield of 47.2% with an ee value of 99.8%.

Compound 4-1 ¹H-NMR(400MHz,CDCl ₃):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 ₂₅H ₃₃BrO ₃Si] ⁺490.3,found 490.3.

Compound I ¹H-NMR(400MHz,CDCl ₃):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),3.74-3.71(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 ₂₃H ₃₁BrO ₂Si] ⁺448.2,found 448.2.

Example 2

The same procedure as in example 1 was repeated except that the following synthetic route was followed and the parameters were adjusted in accordance with Table 1, to obtain the following nuclear magnetism.

Compound 4-2 ¹H-NMR(400MHz,CDCl ₃):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),1.05(s,9H).LC-MS(ESI):m/z calcd for[C ₂₆H ₃₅BrO ₃Si] ⁺504.5,found 504.5.

Example 3

Compound 4-3 ¹H-NMR(400MHz,CDCl ₃):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 ₃₀H ₃₅BrO ₃Si] ⁺552.4,found 552.4.

Compound I ¹H-NMR(400MHz,CDCl ₃):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),3.74-3.71(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 ₂₃H ₃₁BrO ₂Si] ⁺448.2,found 448.2.

Example 4

Compounds 4-4 ¹H-NMR(400MHz,CDCl ₃):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)2.61-2.56(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 ₂₆H ₃₃BrO ₃Si] ⁺504.5,found 504.5.

Example 5

Compound I (2.0 g,4.47 mmol) was dissolved in 20mL of acetonitrile, pyridine (1.06 g,13.41 mmol) was added, (0.11 g,0.894 mmol) 4-Dimethylaminopyridine (DMAP), (0.67 g, 6.704 mmol) succinic anhydride, and the reaction was carried out at room temperature under nitrogen until the spot of the starting material was disappeared as observed by Thin Layer Chromatography (TLC) and the reaction was completed. The reaction solution was concentrated to obtain a pale yellow oily substance, which was separated by silica gel column chromatography, distilled under reduced pressure, and concentrated to dryness to obtain 2.35g of a pale yellow oily compound 5-1 in 96.0% yield.

¹H-NMR(400MHz,CDCl ₃):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),5.24-5.18(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 ₂₇H ₃₅BrO5Si] ⁺548.3,found 548.3.

Example 6

The same procedure as in example 5 was repeated except that the following synthetic route was followed and the parameters were adjusted in accordance with Table 2, to obtain the following nuclear magnetism.

¹H-NMR(400MHz,CDCl ₃):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 ₂₇H ₃₃BrO ₅Si] ⁺546.4,found 546.4.

Example 7

¹H-NMR(400MHz,CDCl ₃):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),5.49(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 ₃₁H ₃₅BrO ₅Si] ⁺596.2,found 596.2.

Example 8

Compound 3B-1 (10.0 g,20.43 mmol) was dissolved in 50mL 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, and the mixture was stirred under nitrogen atmosphere at 35-40℃until the ee value of compound I detected by HPLC was not less than 99%, and the reaction was completed. The reaction solution was directly filtered, the cake was recovered, the filtrate was washed with saturated brine, and the organic phase was concentrated to give a crude product, which was separated by silica gel column chromatography to give 4.81g of Compound 4-1 in a yield of 48.1% and 4.37g of Compound I in a yield of 47.8% and an ee value of 99.8%.

Example 9

The same procedure as in example 8 was repeated except that the following synthetic route was followed and the parameters were adjusted in accordance with Table 3, to obtain the following nuclear magnetism.

Compound 4-2 ¹H-NMR(400MHz,CDCl ₃):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 ₂₆H ₃₅BrO ₃Si] ⁺504.5,found 504.5

Example 10

Compound 4-3 ¹H-NMR(400MHz,CDCl ₃):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 ₃₀H ₃₅BrO ₃Si] ⁺552.4,found 552.4;

Example 11

Compounds 4-4 ¹H-NMR(400MHz,CDCl ₃):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)2.61-2.56(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[C ₂₆H ₃₃BrO ₃Si] ⁺502.5,found 502.5.

Example 12

Compound 3A (20.0 g,44.70 mmol) was dissolved in 100mL of n-hexane, and (19.24 g,223.48 mmol) of vinyl acetate (4.0 g,0.2 w) of the biological enzyme Lipase AK "Amano" was added, and the temperature was raised to 55-60℃under the protection of nitrogen, and the temperature was kept at 55-60℃until the ee value of compound I detected by HPLC was not less than 99% and the reaction was completed. The reaction solution is directly filtered, a filter cake is recovered, the filtrate is concentrated to obtain a crude product, the crude product is dissolved by using 40mL of acetonitrile, triethylamine (TEA), (0.92 g,4.47 mmol) and (3.35 g,33.53 mmol) succinic anhydride are added, the reaction is carried out at room temperature until spots of raw materials are disappeared by TLC observation, n-heptane and water are added into the reaction solution after the reaction is finished, n-heptane phases are collected, the acetonitrile aqueous phase is extracted by using n-heptane, the n-heptane phases are combined, the n-heptane phases are concentrated to dryness under reduced pressure at 35-40 ℃ to obtain 10.4g of the compound 4-1, and the yield is 47.6%.

Acetonitrile and water are added (3.58 g,89.40 mmol) of sodium hydroxide solid, the reaction is carried out at room temperature until the spot of the raw material is disappeared by TLC observation, the acetonitrile phase is collected, the acetonitrile phase is concentrated to dryness under reduced pressure at 35-40 ℃ to obtain 9.26g of compound I, the yield is 46.3%, and the ee value is 99.7%.

Compound 4-1 ¹H-NMR(400MHz,CDCl ₃):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 ₂₅H ₃₃BrO ₃Si] ⁺490.3, found 490.3.

Example 13

The same procedure as in example 12 was repeated except that the following synthetic route was followed and the parameters were adjusted in accordance with Table 4, to obtain the following nuclear magnetism.

Example 14

Example 15

Compounds 4-4 ¹H-NMR(400MHz,CDCl ₃):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)2.61-2.56(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[C ₂₆H ₃₃BrO ₃Si] ⁺504.5,found 504.5.

Example 16

(20.0 G,44.69 mmol) of Compound 3A was dissolved in 100mL of Dichloromethane (DCM), and (13.57 g,134.07 mmol) of triethylamine, (2.73 g,22.34 mmol) of DMAP, (6.84 g,67.035 mmol) of acetic anhydride was added and reacted at room temperature under nitrogen until the TLC observation of the disappearance of the starting material spots was completed. The reaction mixture was stirred with 50mL of saturated brine, separated, and the organic phase was concentrated to give a crude pale yellow oil, which was slurried with 100mL of n-heptane, filtered, and the filtrate was concentrated to give 21.34g of Compound 3B-1 as pale yellow oil in 97.53% yield.

Compound 3B-1 H-NMR(400MHz,CDCl ₃):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 ₂₅H ₃₃BrO ₃Si] ⁺490.3,found 490.3.

Example 17

(10.0 G,20.43 mmol) of compound 3B-1 was dissolved in 50mL of toluene, and (2.17 g,20.43 mmol) of sodium carbonate, (1.0 g,0.1 w) of lipase PS-30 derived from Pseudomonas cepacia, (1.0 g,0.1 w) of water was added, followed by stirring and reacting under nitrogen atmosphere at 35-40℃until the ee value of the compound 5 as detected by HPLC became 99% or more. The reaction solution is directly filtered, a filter cake is recovered, the filtrate is washed with 10mL of saturated common salt water for 1 time, an organic phase is concentrated to obtain a crude product, the crude product is dissolved with 20mL of acetonitrile, (3.62 g,35.75 mmol) of TEA, (0.25 g,2.043 mmol) of DMAP, (1.50 g,15.32 mmol) of maleic anhydride are added, the reaction is carried out at room temperature until spots of raw materials disappear after the TLC observation, 20mL of n-heptane and 25mL of water are added into the reaction solution, an n-heptane phase is collected, the acetonitrile water phase is extracted with n-heptane, the n-heptane phase is combined, and the n-heptane phase is concentrated to be dried under reduced pressure at 35-40 ℃ to obtain 4.79g of a compound 4-1, and the yield is 47.9%.

Acetonitrile and water are added (1.63 g,40.86 mmol) of sodium hydroxide solid, the reaction is carried out at room temperature until the spot of the raw material is disappeared by TLC observation, the acetonitrile phase is collected, the acetonitrile phase is concentrated to dryness under reduced pressure at 35-40 ℃ to obtain 4.39g of compound I, the yield is 48.1%, and the ee value is 99.8%.

Example 18

The same procedures as in example 16 were repeated except that the following synthetic route and the parameters were adjusted in accordance with Table 5, to obtain the following nuclear magnetism of the product.

Compound 3B-2 ¹H-NMR(400MHz,CDCl ₃):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 ₂₆H ₃₅BrO ₃Si] ⁺504.5,found 504.5.

Example 19

The same procedures as in example 17 were repeated except that the following synthetic route and the parameters were adjusted in accordance with Table 6, to obtain the following nuclear magnetism of the product.

Compound 4-2 ¹H-NMR(400MHz,CDCl ₃):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 ₂₆H ₃₅BrO ₃Si] ⁺504.5,found 504.5.

Example 20

Compound 3B-3 ¹H-NMR(400MHz,CDCl ₃):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 ₃₀H ₃₅BrO ₃Si] ⁺552.4,found 552.4.

Example 21

Compound I ¹H-NMR(400MHz,CDCl ₃):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),3.74-3.71(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 ₂₃H ₃₁BrO ₂Si] ⁺448.2,found 448.2

Example 22

Compound 3B-4 ¹H-NMR(400MHz,CDCl ₃):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)2.61-2.56(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[C ₂₆H ₃₃BrO ₃Si] ⁺502.5,found 502.5.

Example 23

The relevant parameters in the above examples 1 to 23 are shown in tables 1 to 6.

TABLE 1

TABLE 2

TABLE 3 Table 3

TABLE 4 Table 4

TABLE 5

TABLE 6

Claims

A method for preparing a chiral compound I by 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 I, and selectively separates the mixture of compound 4 and compound I;

Method 2:

The second method uses the compound shown in formula 3B as a raw material, performs a hydrolysis reaction under the action of biological enzyme B and alkali to obtain the compound 4 and the compound I, and selectively separates the mixture of the compound 4 and the compound I;

wherein _R1 is a _C1 - _C12 straight or branched acyl group which is substituted or unsubstituted by Ra, a benzoyl group, a _C3 - _C6 straight or branched alkenoyl group which is substituted or unsubstituted by Ra, and the substituent Ra of each group is independently selected from a _C1 - _C6 straight or branched alkyl group, a _C1 - _C6 straight 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 - _C18 heterocyclic aromatic group, and the heteroatom on the heterocyclic aromatic group is selected from O, N or S; ₁ 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 fixed 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, recombinant from Aspergillus oryzae; the biological enzyme A is preferably lipase AK, lipase from Pseudomonas fluorescens or Candida antarctica lipase B Novozym 435 fixed on acrylic resin;

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.

The method according to claim 1, characterized in that: the acylating agent of the method 1 is selected from vinyl esters or isopropenyl esters, wherein the vinyl esters are selected from C ₁ -C ₁₂ straight or branched acid vinyl esters substituted or unsubstituted by Rc, vinyl benzoate, and C ₃ -C ₆ straight or branched olefinic acid vinyl esters substituted or unsubstituted by Rc; the isopropenyl esters are selected from C ₁ -C ₁₂ straight or branched acid isopropenyl esters substituted or unsubstituted by Rc, isopropenyl benzoate, and C ₃ -C ₆ straight or branched olefinic acid isopropenyl esters substituted or unsubstituted by Rc; the substituent Rc of each group is independently selected from C ₁ -C ₆ straight or branched alkyl, C ₁ -C ₆ straight or branched alkoxy, hydroxyl, amino, halogen, nitro, cyano, C ₁ -C ₆ amide, C ₃ -C ₆ cycloalkyl, C ₁ -C ₆ sulfanyl, C ₁ -C ₆ amide, C ₃ -C ₆ cycloalkyl, phenyl or C ₃ -C ₁₈ heterocyclic aromatic group, wherein the heteroatom on 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, vinyl 4-methylpentyl, isopropylene 4-methylpentyl, 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.

The method according to claim 1, characterized in that: the acylation reaction of the method 1 is carried out in an organic solvent A, and the organic solvent A is selected from one or any combination of alkane, aromatic hydrocarbon, chloroalkane, nitrile 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 to 15 mL, more preferably 1 g: 5 to 8 mL;

and/or the acylation reaction temperature in the method 1 is 30 to 80° C., preferably 55 to 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.

The method according to claim 1, characterized in that: the hydrolysis reaction of the method 2 is carried out in water and an organic solvent B, 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 to 15 mL, more preferably 1 g: 3 to 8 mL.

And/or the hydrolysis reaction temperature in method 2 is 30-80°C, preferably 35-40°C.

The method according to claim 1, characterized in that 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, and the reaction formula is as follows:

wherein _R1 is a _C1 - _C12 straight or branched acyl group which is substituted or unsubstituted by Ra, a benzoyl group, a _C3 - _C6 straight or branched alkenoyl group which is substituted or unsubstituted by Ra, and the substituent Ra of each group is independently selected from a _C1 - _C6 straight or branched alkyl group, a _C1 - _C6 straight 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 - _C18 heterocyclic aromatic group, and the heteroatom on the heterocyclic aromatic group is selected from O, N or S; ₁ is preferably acetyl, propionyl, butyryl, isobutyryl, 2-methylbutyryl, 3-methylbutyryl, pivaloyl, 2-methylvaleryl, 3-methylvaleryl, 4-methylvaleryl, hexanoyl, lauroyl, benzoyl or acryloyl; R ₂ is selected from

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, and the reaction formula is as follows:

The method according to claim 5 or 6 is characterized in that: the column chromatography separation method 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.

The method according to claim 5 or 6, characterized in that: the catalyst in step a 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-trimethylpyridine, 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.

An intermediate compound with the following structure:

* represents chiral carbon; R is C ₁ -C ₁₂ straight chain or branched chain acyl substituted or unsubstituted by Ra, C ₃ -C ₆ straight chain or branched chain alkenoyl substituted or unsubstituted by Ra, wherein the substituent Ra of each group is independently selected from C ₁ -C ₆ straight or branched alkyl, C ₁ -C ₆ straight or branched alkoxy, hydroxy, amino, halogen, nitro, cyano, C ₁ -C ₆ amide, C ₃ -C ₆ cycloalkyl, C ₁ -C ₆ sulfanyl, C ₁ -C ₆ amide, C ₃ -C ₆ cycloalkyl, phenyl or C ₃ -C ₁₈ heterocyclic aromatic group, and the heteroatom on 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:

wherein _R1 is a _C1 - _C12 straight or branched acyl group which is substituted or unsubstituted by Ra, or a _C3 - _C6 straight or branched alkenoyl group which is substituted or unsubstituted by Ra, and the substituent Ra of each group is independently selected from a _C1 - _C6 straight or branched alkyl group, a _C1 - _C6 straight 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 - _C18 heterocyclic aromatic group, and the heteroatom on the heterocyclic aromatic group is selected from O, N or S; ₁ 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, R ₂ is selected from

The intermediate compound is preferably the following compound:

A method for preparing an eribulin drug, characterized by comprising the method according to any one of claims 1 to 5 or the method according to any one of claims 6 to 8.