Method for preparing 2-hydroxyethyl aminocaproate compound and application of 2-hydroxyethyl aminocaproate compound

Abstract

The invention relates to a method for preparing a 2-hydroxyethyl amino hexanoate compound and application of the 2-hydroxyethyl amino hexanoate compound. Specifically, the invention provides a method for preparing a compound shown as a formula (I) or a salt thereof, the method comprises the step of reacting a compound shown as a formula (A) with a compound shown as a formula (B) to form the compound shown as the formula I. The whole process is simple and convenient to operate and high in yield, and the obtained sample is excellent in quality and suitable for large-scale production. # imgabs0 #

Description

A method for preparing 2-hydroxyethylaminocaproate compounds and its application Technical Field

[0001] The present invention relates to a method for preparing 2-hydroxyethylaminocaproate compounds and application thereof. Background Art

[0002] Currently, nucleic acid drug delivery systems can be divided into two categories: viral vector systems and non-viral systems. Liposome-mediated nucleic acid drug delivery is the main method of non-viral delivery systems.

[0003] In order to deliver in vitro synthesized mRNA into cells and achieve translation and expression of target proteins, many problems need to be overcome. The first and foremost problem is the enzymatic degradation and cell membrane barrier of mRNA delivery into cells. Both of the currently approved new crown mRNA vaccines use LNP delivery systems to achieve mRNA delivery. The LNP delivery system can not only efficiently deliver mRNA to specific target cells and prevent mRNA degradation, but also help mRNA escape from endosomes into the cytoplasm. The ionizable lipid used by Moderna is SM-102, and the ionizable lipid used by Pfizer is ALC-0315.

[0004] CN202210651178.7 reports a new type of ionizable lipid, represented by compound 1, which has a more excellent delivery effect. At the same time, the prepared liposomes are more distributed in the liver and less in the spleen, with better organ targeting.

[0005] The preparation method is generally as follows:

[0006] Other common methods for preparing ionizable lipids include: 1) US10106490 reported a method for preparing ionizable lipids by SN1 nucleophilic reaction of amino alcohols and bromoesters,

[0007] 2) WO2018170306 also reports a similar reaction process, namely, a method for obtaining ionizable lipid h2 by SN1 reaction of compound f2 with amino alcohol.

[0008] Summary of the Invention

[0009] The present disclosure provides a method for preparing a compound of formula I or a pharmaceutically acceptable salt thereof.

[0010] comprising the step of reacting a compound of formula A with a compound of formula B to form a compound of formula I,

[0011] Among them L 1 and L 2 are each independently selected from -C(O)O-, -OC(O)-, -C(O)- or -OC(O)O-;

[0012] H 1 and H 2 Each independently selected from C 1-12 Heteroalkylene, C 1-12 Alkylene, C 2-12 alkenylene;

[0013] H 3 Selected from C 1-24 Alkylene, C 2-24 Alkenylene, C 3-8 Cycloalkylene or C 3-8 cycloalkenylene;

[0014] H 4 Selected from C 2-11 Heteroalkylene, C 2-11 Alkylene, C 3-11 alkenylene;

[0015] R 1 and R 2 Each independently selected from C 1-24 Alkyl or C 2-24 alkenyl;

[0016] R 3 Selected from -CN, -C(O)OR 4 、-OC(O)R 4 、-OR 5 or -NR 5 C(O)R 4 , R 4 Selected from C 1-6 Alkyl or C 2-6 Alkenyl, R 5 Selected from hydrogen, C 1-6 Alkyl or C 2-6 Alkenyl.

[0017] In some embodiments, the compound of formula A is reacted with the compound of formula B under reducing agent conditions, wherein the reducing agent is selected from sodium borohydride or sodium triacetoxyborohydride.

[0018] Furthermore, in some embodiments, the reaction further comprises a base, including but not limited to N,N-diisopropylethylamine.

[0019] In other embodiments, the compound of formula I is a compound of formula I-1,

[0020] The method comprises the steps of reacting a compound of formula A-1 with a compound of formula B-1,

[0021] Among them H 1 、H 2 、H 4 、R 1 and R 2 As defined in the compounds of formula I.

[0022] In some embodiments, H in the compound of Formula I or Formula II 1 and H 2 At least one of them is C 1-12 Heteroalkylene, including C 2-9 heteroalkylene, C3 heteroalkylene, C4 heteroalkylene, C5 heteroalkylene, C6 heteroalkylene, C7 heteroalkylene, C8 heteroalkylene, C9 heteroalkylene, C 10 Heteroalkylene, C 11 Heteroalkylene or C 12 In some embodiments, H in the compound of Formula I or Formula II 1 and H 2 At least one of them is C 2-9 Heteroalkylene, preferably C 2-5 Heteroalkylene.

[0023] In some embodiments, H in the compound of Formula I or Formula II 1 and H 2 At least one of them is C 2-9 A heteroalkylene group containing at least one oxygen heteroatom.

[0024] In some embodiments, H in the compound of Formula I or Formula II 1 and H 2 At least one of them is C 2-9 Heteroalkylene, wherein the heteroalkylene contains one oxygen heteroatom.

[0025] In other embodiments, R 1 Selected from H 1 Selected from C 2-9 Heteroalkylene.

[0026] In other embodiments, R 1 Selected from H 1 Selected from C 2-9 Heteroalkylene, wherein the heteroalkylene contains one oxygen heteroatom.

[0027] In other embodiments, R 1 Selected from H 1 Selected from C 2-9 Heteroalkylene, wherein the heteroalkylene contains an oxygen heteroatom; R 2 Selected from C 1-24 Alkyl; H 2 Selected from C 2-9 Alkylene.

[0028] In other embodiments, R 2 Selected from H 2 Selected from C 2-9 Heteroalkylene.

[0029] In other embodiments, R 2 Selected from H 2 Selected from C 2-9 Heteroalkylene, wherein the heteroalkylene contains one oxygen heteroatom.

[0030] In other embodiments, R 2 Selected from H 2 Selected from C 2-9 Heteroalkylene, wherein the heteroalkylene contains an oxygen heteroatom; R 1 Selected from C 1-24 Alkyl; H 1 Selected from C 2-9 Alkylene.

[0031] On the other hand, in some embodiments, R 1 Selected from H 1 Selected from C 2-9 Alkylene; R 2 Selected from C 1-24 Alkyl; H 2 Selected from C 2-9 Alkylene.

[0032] In some embodiments, R 2 Selected from H 2 Selected from C 2-9 Alkylene; R 1 Selected from C 1-24 Alkyl; H 1 Selected from C 2-9 Alkylene.

[0033] In some embodiments, the compound of formula I is a compound of formula I-2

[0034] The method comprises the steps of reacting a compound of formula A-2a with a compound of formula B-2a,

[0035] Alternatively, the step of reacting the compound of formula A-2b with the compound of formula B-2b,

[0036] Furthermore, the method for preparing the compound of formula I or a pharmaceutically acceptable salt thereof further comprises the step of converting the compound of formula B-2a5 into the compound of formula B-2a.

[0037] Wherein, P is a hydroxyl protecting group, such as benzyl or benzoyl.

[0038] In some embodiments, the conditions for removal of the hydroxy protecting group are hydrogenation conditions comprising a Pd / C catalyst.

[0039] In other embodiments, the method for preparing a compound of formula I or a pharmaceutically acceptable salt thereof further comprises the step of converting a compound of formula B-2b5 into a compound of formula B-2b.

[0040] Wherein, P is a hydroxyl protecting group, such as benzyl or benzoyl.

[0041] In some embodiments, the method for preparing a compound of Formula I or a pharmaceutically acceptable salt thereof comprises reacting a compound of Formula B-2a5 under hydrogenation conditions to form a compound of Formula B-2a, and then reacting the compound of Formula B-2a with a compound of Formula A-2a to form a compound of Formula I-2.

[0042] On the other hand, in some embodiments, the compound of formula I is a compound of formula I-3

[0043] The method comprises the steps of reacting a compound of formula A-3a with a compound of formula B-3a,

[0044] The present disclosure also provides a pharmaceutical composition comprising the compound of formula I or a pharmaceutically acceptable salt thereof prepared by the aforementioned method and one or more pharmaceutically acceptable excipients.

[0045] In some embodiments, the pharmaceutical composition further comprises an active agent selected from, but not limited to, nucleotides or nucleic acids, such as mRNA.

[0046] On the other hand, the present disclosure also provides the use of the compound of formula I or its pharmaceutically acceptable salt prepared by the aforementioned method or the aforementioned pharmaceutical composition in the preparation of a drug for preventing and / or treating an induced immune response in a subject.

[0047] On the other hand, the present disclosure also provides the use of the compound of formula I or its pharmaceutically acceptable salt prepared by the aforementioned method or the aforementioned pharmaceutical composition in the preparation of a drug for preventing and / or treating diseases or conditions related to overexpression of the polypeptide.

[0048] On the other hand, the present disclosure also provides the use of the compound of formula I or its pharmaceutically acceptable salt prepared by the aforementioned method or the aforementioned pharmaceutical composition in the preparation of a drug for preventing and / or treating diseases or conditions related to insufficient polypeptide expression.

[0049] The method of the present disclosure may further comprise post-processing operations, such as one or more steps of filtration, extraction, concentration, column chromatography or chiral separation to obtain a pure target product.

[0050] The compound salts described in the present disclosure include "acid" addition salts and "base" addition salts. For example, salts formed by acid-base reaction with a basic group (amino group), wherein the acid includes an organic acid or an inorganic acid. In addition, the compound salts also include salts formed by quaternization with a basic group (amino group), wherein the quaternizing agent includes a linear or branched chlorinated hydrocarbon.

[0051] Unless otherwise stated, the terms used in this disclosure have the following meanings:

[0052] A "pharmaceutical composition" refers to a mixture containing one or more compounds described herein, or their physiologically acceptable salts or prodrugs, together with other chemical components, as well as other components such as physiologically acceptable carriers and excipients. The purpose of a pharmaceutical composition is to facilitate administration to an organism, facilitating absorption of the active ingredients and thereby exerting their biological activity.

[0053] "Pharmaceutically acceptable excipients" include, but are not limited to, any adjuvant, carrier, excipient, glidant, sweetener, diluent, preservative, dye / colorant, flavoring agent, surfactant, wetting agent, dispersant, suspending agent, stabilizer, isotonic agent, solvent or emulsifier approved by the U.S. Food and Drug Administration for use in humans or domestic animals.

[0054] As used herein, an "effective amount" or "therapeutically effective amount" encompasses an amount sufficient to ameliorate or prevent the symptoms or conditions of a medical condition. An effective amount also refers to an amount sufficient to permit or facilitate diagnosis. The effective amount for a particular patient or veterinary subject may vary depending on factors such as the condition to be treated, the patient's overall health, the route and dosage of administration, and the severity of side effects. An effective amount can be the maximum dose or dosage regimen that avoids significant side effects or toxic effects.

[0055] The term "nucleic acid" is a polymer composed of nucleotides, such as deoxyribonucleotides (DNA) or ribonucleotides (RNA).

[0056] The term "oligonucleotide" refers to a single-stranded or double-stranded nucleotide polymer of 2 to 100 nucleotides in length. "Polynucleotide" refers to a single-stranded or double-stranded polymer composed of nucleotide monomers. In some embodiments, a polynucleotide is composed of more than 100 nucleotides in length.

[0057] In other embodiments, exemplary polynucleotides include, but are not limited to, mRNA.

[0058] "Alkyl" refers to a saturated aliphatic hydrocarbon group, including straight-chain and branched-chain alkyl groups. In some embodiments, the alkyl group has 1-4 carbon atoms, also known as C 1-4 In some embodiments, an alkyl group has 10-22 carbon atoms, also known as a C 10-22 In some embodiments, the alkyl group has 4-22 carbon atoms, also known as C 4-22 alkyl.

[0059] The alkyl group may be unsubstituted or substituted with one or more groups selected from halogen, hydroxy, amino, oxo, alkyl, alkoxycarbonyl, amido, alkylamido, dialkylamido, nitro, amino, alkylamino, dialkylamino, carboxy, thio and thioalkyl groups.

[0060] "Heteroalkyl" refers to a straight or branched chain alkyl group preferably having 1 to 14 carbons, more preferably 2 to 10 carbons in the chain, wherein one or more carbons are substituted with a heteroatom selected from S, O, and N. Exemplary heteroalkyl groups include alkyl ethers, secondary and tertiary alkylamines, amides, alkyl sulfides, and the like.

[0061] The heteroalkyl group can be unsubstituted or substituted with one or more groups selected from halo, hydroxy, alkyl, amino, oxo, alkoxycarbonyl, amido, alkylamido, dialkylamido, nitro, amino, alkylamino, dialkylamino, carboxy, thio, and thioalkyl groups.

[0062] "Alkenyl" refers to an unsaturated aliphatic hydrocarbon group, including straight-chain and branched alkenyl groups. In some embodiments, the alkenyl group has 1-4 carbon atoms, also known as C 1-4 In some embodiments, the alkenyl group has 10-22 carbon atoms and is also referred to as a C 10-22 In some embodiments, the alkenyl group has 4-22 carbon atoms and is also referred to as a C 4-22 Alkenyl. Exemplary alkenyl groups include ethenyl, propenyl, n-butenyl, isobutenyl, 3-methylbut-2-enyl, n-pentenyl, heptenyl, octenyl, cyclohexyl-butenyl, and decenyl.

[0063] The alkenyl group may be unsubstituted or substituted with one or more groups selected from halogen, hydroxy, amino, oxo, alkyl, alkoxycarbonyl, amido, alkylamido, dialkylamido, nitro, amino, alkylamino, dialkylamino, carboxy, thio and thioalkyl groups.

[0064] A "monovalent group" is a compound formed by formally eliminating a monovalent atom or group. A "subunit" is a compound formed by formally eliminating two monovalent or one divalent atom or group.

[0065] The term "alkylene" refers to the portion of an alkane molecule remaining after removing two hydrogen atoms. In some embodiments, an alkylene group has 1-4 carbon atoms and is also referred to as a C 1-4 In some embodiments, an alkyl group has 10-22 carbon atoms, also known as a C 10-22 In some embodiments, the alkyl group has 4-22 carbon atoms, also known as C 4-22 Alkylene.

[0066] Similarly, the definitions of "alkyleneoxy", "heteroalkylene", "alkenylene", "alkenyleneoxy", "cycloalkylene" and "heterocycloalkylene" are the same as "alkylene".

[0067] The terms "to form" and "to convert" in this disclosure do not necessarily imply a single-step conversion reaction between two substrates; rather, the conversion reaction between two substrates may be a single-step or multi-step reaction. For example, if an intermediate contains an amino protecting group, the intermediate undergoes a step of deamination with a protecting agent and then reacts with the corresponding substrate to obtain the corresponding target product.

[0068] "Hydroxy protecting group" is a suitable group for protecting hydroxyl group known in the art, see the literature ("Protective Groups in Organic Synthesis", 5 Th The hydroxy protecting group in Ed.TW Greene & P.GMWuts. As an example, it includes but is not limited to benzyl or benzoyl.

[0069] The "excipients" described in this disclosure include, but are not limited to, any adjuvant, carrier, glidant, sweetener, diluent, preservative, dye / colorant, flavoring agent, surfactant, wetting agent, dispersant, suspending agent, stabilizer, isotonic agent or emulsifier that has been approved by the U.S. Food and Drug Administration for use by humans or livestock animals.

[0070] The structures of the compounds were determined by nuclear magnetic resonance (NMR) and / or mass spectrometry (MS). -6The unit of ppm is given. NMR measurements were performed using a Bruker AVANCE-400 NMR spectrometer. The solvents used were deuterated dimethyl sulfoxide (DMSO-d6), deuterated chloroform (CDCl3), deuterated methanol (CD3OD), and tetramethylsilane (TMS) as the internal standard.

[0071] HPLC determination can be performed using an Agilent 1200 high pressure liquid chromatograph (Evo C18 4.6*250mm, 5um, column or Xtimate C18 2.1*30mm column).

[0072] The thin layer chromatography silica gel plate uses Yantai Huanghai HSGF254 or Qingdao GF254 silica gel plate. The specification of the silica gel plate used in thin layer chromatography (TLC) is 0.15mm~0.2mm, and the specification used for thin layer chromatography separation and purification products is 0.4mm~0.5mm.

[0073] The flash column purification system used was Combiflash Rf150 (TELEDYNE ISCO) or Isolara one (Biotage). DETAILED DESCRIPTION

[0074] The present disclosure will be described in detail below in conjunction with specific embodiments so that those skilled in the art can have a more comprehensive understanding of the present disclosure. The specific embodiments are only used to illustrate the technical solutions of the present disclosure and do not limit the present disclosure in any way.

[0075] Example 1

[0076] Step 1:

[0077] To a NaOH aqueous solution at 0-5°C, add toluene and Al (8 g) and stir at room temperature for 1 hour. Slowly add tert-butyl bromoacetate dropwise and heat with stirring to react overnight. Add water and extract three times with methyl tert-butyl ether. Combine the organic phases and wash three times with water. Combine the aqueous phases. Use the aqueous phase directly in the next reaction.

[0078] Step 2:

[0079] With stirring, concentrated hydrochloric acid was slowly added to adjust the pH to 3, and the mixture was extracted with DCM. The organic phases were combined, washed with saturated brine, and concentrated under reduced pressure. The crude product was purified by column chromatography to afford A4 in a two-step yield of 90%.

[0080] Step 3:

[0081] Compound A4 was dissolved in dichloromethane, cooled to 0-5°C, and heptadecanol (A5), DMAP, and EDCI were added sequentially. The mixture was stirred, the ice bath removed, and the reaction was allowed to react at room temperature overnight. After TLC monitoring of the complete reaction of heptadecanol, water was added to the reaction solution and the layers separated. The aqueous phase was extracted with DCM. The combined organic phases were washed with saturated sodium bicarbonate solution, then with saturated brine, and concentrated under reduced pressure to obtain the crude product. The crude product was purified by column chromatography to obtain A6 in a 95% yield.

[0082] Step 4:

[0083] Compound A6 was dissolved in THF, and Pd / C (10%) was added. Hydrogen was introduced and the pressure was increased to 0.5 MPa. The reaction was stirred at room temperature overnight. After TLC monitoring, the reaction was completed, filtered, washed with THF, and concentrated to obtain a crude product. The crude product was purified by column chromatography to obtain A7 in an 85% yield.

[0084] Step 5:

[0085] Compound A7 was dissolved in DCM, cooled to 0-5°C, and Dess-Martin periodinane was added portionwise. The reaction was stirred at room temperature at 0-5°C for 2-4 hours. Upon completion, the reaction was quenched with a mixed solution of sodium bicarbonate and sodium sulfite. The organic phase was washed with saturated sodium bicarbonate solution and then with saturated brine, and vacuum rotary evaporation was performed to obtain the crude product. The crude product was purified by column chromatography to obtain A8 in a 70% yield.

[0086] Example 2

[0087] Step 1:

[0088] Dissolve 6-aminocaproic acid (B1, 3.5 kg) in 21.8 kg of ethanol and add 3.0 kg of potassium hydroxide in batches. Add 6.8 kg of benzyloxyethyl bromide and stir at 50-60°C for 20 hours. Cool, filter, and concentrate under reduced pressure to remove most of the ethanol. Add methyl tert-butyl ether and water, adjust the pH to 6, separate, and retain the aqueous layer. Wash with methyl tert-butyl ether and dichloromethane, respectively. Use the aqueous phase directly in the next reaction.

[0089] Step 2:

[0090] The solution obtained in the previous step was added to 1,4-dioxane (22.5 kg), followed by a 50% aqueous solution of NaOH (1.46 kg). Boc2O (4.23 kg) was slowly added dropwise, and the reaction was stirred. The dioxane was concentrated to remove the dioxane, and water was added. The mixture was washed twice with methyl tert-butyl ether. The pH was adjusted to 5-6 with 2N hydrochloric acid, and the mixture was extracted twice with methyl tert-butyl ether. The organic phase was washed with 5% NaHCO3aq. The organic phases were combined, filtered, and the filtrate was concentrated to obtain an oily product, B4. The yield for the two steps was estimated to be 30%.

[0091] Step 3:

[0092] Compound B4 was dissolved in dichloromethane (26 kg), and undecanol (0.94 kg), EDCI (1.57 kg), DIPEA (1.77 kg), and DMAP (0.17 kg) were added portionwise. The reaction was stirred at room temperature for 14-18 hours. Purified water (15 kg) was added, and the mixture was separated. The mixture was washed with 1% citric acid and then 3% citric acid. The organic phase was washed with saturated NaCl (10.0 kg), separated, filtered, and concentrated to dryness to obtain an oily product B5 in a 73% yield.

[0093] Step 4:

[0094] Compound A5 (2.8 kg) was dissolved in acetonitrile (22.0 kg, 10 V) and stirred evenly. 4 M HCl dioxane solution (5.3 L) was added and reacted at room temperature for 1-4 h. The mixture was cooled to -10-0°C and stirred to precipitate a solid. The solid was filtered, washed with methyl tert-butyl ether, and dried in vacuo at 40°C to obtain a white solid B6 in a yield of 72%.

[0095] Example 3

[0096] Step 1:

[0097] Dissolve compound B6 (2.0 kg) in ethanol (16 kg, 10 V) and stir until the solution is clear. Add 10% wet palladium on carbon (0.4 kg, 20% wt.), and vacuum-explace the reaction system with hydrogen three times. Raise the temperature to 40 ± 5°C and continue stirring for 8–10 hours. Filter and wash with ethanol. Concentrate the filtrate under reduced pressure, cool to allow a solid to precipitate, and continue stirring for 4–6 hours. Filter and wash the filter cake with methyl tert-butyl ether. Vacuum dry for 16 hours to obtain B7 as a white solid in a 90% yield.

[0098] Step 2:

[0099] Dissolve compound A8 (665 g) in dichloromethane (10 kg, 12 V), add compound B7 (550 g) in portions, then add N,N-diisopropylethylamine (324 g) and acetic acid (202 g) in sequence. Cool to 0-5°C, then add sodium triacetoxyborohydride (887 g) in portions. Stir and react for 2-4 hours. Quench with purified water, wash the organic phase with aqueous sodium bicarbonate solution and aqueous sodium chloride solution, and concentrate under reduced pressure.

[0100] Methanol was added and stirred until the solution became clear; activated carbon powder (40 g, 5% wt) was added for decolorization; the mixture was heated to 30°C and stirred for 1 hour; the mixture was filtered, concentrated, and the crude product was purified by column chromatography to obtain the desired product in a yield of 80%.

Claims

1. A method for preparing a compound of formula I or a pharmaceutically acceptable salt thereof, comprising the step of reacting a compound of formula A with a compound of formula B to form a compound of formula I, Among them L 1 and L 2 are each independently selected from -C(O)O-, -OC(O)-, -C(O)- or -OC(O)O-; H 1 and H 2 Each independently selected from C 1-12 Heteroalkylene, C 1-12 Alkylene, C 2-12 alkenylene; H 3 Selected from C 1-24 Alkylene, C 2-24 Alkenylene, C 3-8 Cycloalkylene or C 3-8 cycloalkenylene; H 4 Selected from C 2-11 Heteroalkylene, C 2-11 Alkylene, C 3-11 alkenylene; R 1 and R 2 Each independently selected from C 1-24 Alkyl or C 2-24 alkenyl; R 3 Selected from -CN, -C(O)OR 4 、-OC(O)R 4 、-OR 5 or -NR 5 C(O)R 4 , R 4 Selected from C 1-6 Alkyl or C 2-6 Alkenyl, R 5 Selected from hydrogen, C 1-6 Alkyl or C 2-6 Alkenyl.

2. The method according to claim 1, wherein the compound of formula A reacts with the compound of formula B under a reducing agent, and the reducing agent is selected from sodium borohydride or sodium triacetoxyborohydride.

3. The method according to claim 1 or 2, further comprising a base, preferably N,N-diisopropylethylamine.

4. The method according to any one of claims 1 to 3, wherein the compound of formula I is a compound of formula I-1, The method comprises the steps of reacting a compound of formula A-1 with a compound of formula B-1, Among them H 1 、H 2 、H 4 、R 1 and R 2 As defined in claim 1.

5. The method according to any one of claims 1 to 4, wherein H in the compound of formula I is 1 and H 2 At least one of them is C 1-12 Heteroalkylene, preferably C 2-9 Heteroalkylene, more preferably C 2-5 Heteroalkylene.

6. The method according to any one of claims 1 to 5, wherein R 1 Selected from H 1 Selected from C 2-9 Heteroalkylene.

7. The method according to any one of claims 1 to 5, wherein R 2 Selected from H 2 Selected from C 2-9 Heteroalkylene.

8. The method according to any one of claims 1 to 5, wherein the compound of formula I is a compound of formula I-2 The method comprises the steps of reacting a compound of formula A-2a with a compound of formula B-2a, Alternatively, the step of reacting the compound of formula A-2b with the compound of formula B-2b, 9. The method according to claim 8, further comprising the step of converting the compound of formula B-2a5 into the compound of formula B-2a. in, P is a hydroxyl protecting group, such as benzyl or benzoyl.

10. The method according to claim 9, wherein the conditions for removing the hydroxy protecting group are hydrogenation conditions, and the hydrogenation conditions preferably contain a Pd / C catalyst.

11. The method according to any one of claims 1 to 10, comprising reacting a compound of formula B-2a5 under hydrogenation conditions to form a compound of formula B-2a, and then reacting the compound of formula B-2a with a compound of formula A-2a to form a compound of formula I-2, 12. A pharmaceutical composition comprising a compound of formula I or a pharmaceutically acceptable salt thereof prepared by the method according to any one of claims 1 to 11 and one or more pharmaceutically acceptable excipients.

13. The pharmaceutical composition according to claim 12, further comprising an active agent, preferably a polynucleotide or nucleic acid, such as mRNA.

14. Use of the compound of formula I or a pharmaceutically acceptable salt thereof prepared by the method according to any one of claims 1 to 11, or the pharmaceutical composition according to claim 12, in the preparation of a medicament for preventing and / or treating an induced immune response in a subject.

15. Use of the compound of formula I or a pharmaceutically acceptable salt thereof obtained by the method of any one of claims 1 to 11, or the pharmaceutical composition of claim 12, in the preparation of a medicament for preventing and / or treating diseases or conditions associated with overexpression of the polypeptide.

16. Use of the compound of formula I or a pharmaceutically acceptable salt thereof obtained by the method of any one of claims 1 to 11, or the pharmaceutical composition of claim 12, in the preparation of a medicament for preventing and / or treating diseases or conditions associated with insufficient polypeptide expression.

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