Novel mRNA capping compound and use thereof

Abstract

The present invention relates to a novel mRNA capping analog represented by formula (I'), each group being as defined in the description. The capping analog has excellent stability, can improve capping efficiency, reduce the uncapping rate, and promote transcription and translation effects.

Description

New mRNA capping compounds and their applications

[0001] This application claims priority to Chinese Patent Application No. 202410178129.5 filed on February 8, 2024, Chinese Patent Application No. 202410381573.7 filed on March 29, 2024, and Chinese Patent Application No. 202510108945.3 filed on January 22, 2025, and the contents of the above-mentioned Chinese patent application disclosures are hereby incorporated by reference in their entirety as part of this application. Field of the Invention

[0002] The present invention belongs to the field of biomedicine, and in particular relates to an mRNA capping compound and an application thereof in mRNA capping. Background Art

[0003] The 5' cap structure is essential for the initiation of mRNA translation. It provides a signal for ribosome recognition of mRNA, assisting ribosome binding and enabling translation to begin at the AUG. The cap structure also increases mRNA stability, protecting it from 5'→3' exonucleases, effectively resisting degradation by 5' exonucleases. During protein synthesis, the cap structure also serves as a unique identifier for recruiting protein factors for pre-mRNA splicing, polyadenylation, and nuclear export. It also serves as an anchor for recruiting initiation factors, facilitating ribosome recognition and binding to mRNA, enabling the correct initiation of translation.

[0004] The 5' cap structure plays an important role in maintaining mRNA stability in vivo and promoting protein translation. Natural cap analogs can be recognized and hydrolyzed by the decapping enzyme (DCP2), reducing mRNA stability in vivo and ultimately reducing the translation efficiency of the target mRNA.

[0005] Therefore, there is an urgent need in the art to develop a new mRNA capping compound to improve the stability of mRNA in vivo.

[0006] SUMMARY OF THE INVENTION

[0007] To address the above-mentioned issues, the present application provides a novel mRNA capping compound, which has the following advantages: (1) mRNA modified with the cap analog has higher stability, specifically, strong resistance to decapping enzymes. (2) mRNA modified with the cap analog has higher translation efficiency for a long time (72 hours) in cells, which can achieve long-term translation expression of mRNA.

[0008] Specifically, in one aspect, the present invention provides a compound of formula (I'), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0009] in,

[0010] R X1 OR a ;

[0011] R X2 OR b ;

[0012] W is selected from O or S;

[0013] R1 is selected from halogen or OR c ;

[0014] R'1 is selected from H or halogen;

[0015] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0016] R'2 is selected from H or halogen;

[0017] R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ;

[0018] R4 is selected from halogen, OR f or

[0019] R5 is selected from halogen or OR g ;

[0020] R6 is selected from halogen or OR h ;

[0021] R7 is selected from halogen or OR i ;

[0022] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CHO, OCH2, CH2CH2O, OCH2CH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2; and at least one of the following conditions is met:

[0023] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0024] 2) X1 is CH2CH2O, OCH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2,

[0025] 3) X2 is OCH2CH2, CH2O, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2;

[0026] 4) X3 is OCH2CH2;

[0027] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0028] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0029] R' is selected from H or halogen;

[0030] or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0031] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0032] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0033] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0034] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, preferably deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, preferably deuterium.

[0035] In another aspect, the present invention provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0036] in,

[0037] R X1 OR a ;

[0038] R X2 OR b ;

[0039] W is selected from O or S;

[0040] R1 is selected from halogen or OR c ;

[0041] R2 is selected from halogen or OR d ;

[0042] R3 is selected from halogen or OR e ;

[0043] R4 is selected from halogen, OR f or

[0044] R5 is selected from halogen or OR g ;

[0045] R6 is selected from halogen or OR h ;

[0046] R7 is selected from halogen or OR i ;

[0047] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0048] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0049] 2) X1 is CH2CH2O,

[0050] 3) X2 is OCH2CH2;

[0051] 4) X3 is OCH2CH2;

[0052] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0053] R and R' are selected from H or halogen;

[0054] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0055] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0056] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0057] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0058] In another aspect, the present invention provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0059] in,

[0060] X1, X2 and X3 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0061] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0062] 2) X1 is CH2CH2O,

[0063] 3) X2 is OCH2CH2;

[0064] R X1 OR a ;

[0065] R X2 OR b ;

[0066] W is selected from O or S;

[0067] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2;

[0068] R1 is selected from halogen or OR c ;

[0069] R2 is selected from halogen or OR d ;

[0070] R3 is selected from halogen or OR e ;

[0071] R4 is selected from halogen or OR f ;

[0072] R5 is selected from halogen or OR g ;

[0073] R and R' are selected from H or halogen;

[0074] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0075] B1, B2 and B3 are independently selected from natural, modified or unnatural nucleobases;

[0076] R a 、R b 、R c 、R d 、R e 、R f and R g independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0077] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0078] In another aspect, the present invention provides an RNA molecule comprising a compound of formula (I) of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof at the 5' end.

[0079] In another aspect, the present invention provides a kit for capping RNA transcripts, comprising a compound of formula (I) of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof.

[0080] In another aspect, the present invention provides use of the compound of formula (I) of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof as an in vitro co-transcribed RNA capping agent.

[0081] In another aspect, the present invention provides a method for synthesizing RNA, comprising incubating a compound of formula (I) of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof with a nucleotide template to perform template transcription.

[0082] In another aspect, the present invention provides a complex comprising a compound of formula (I) of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, and a DNA template, wherein the DNA template includes a promoter region containing a transcription start site having a first nucleotide at nucleotide position +1 and a second nucleotide at nucleotide position +2; and B2 is complementary to the nucleobase at transcription template position +1 on the DNA template, and B3 is complementary to the nucleobase at transcription template position +2 on the DNA template.

[0083] Detailed Description of the Invention

[0084] definition

[0085] Chemical definition

[0086] Definitions of specific functional groups and chemical terms are described in more detail below.

[0087] When a numerical range is listed, it is intended to include every value and sub-range within the stated range. For example, "C 1-6 "Alkyl" includes C1, C2, C3, C4, C5, C6, C 1-6 、C 1-5 、C 1-4 、C 1-3 、C1-2 、C 2-6 、C 2-5 、C 2-4 、C 2-3 、C 3-6 、C 3-5 、C 3-4 、C 4-6 、C 4-5 and C 5-6 alkyl.

[0088] “C 1-6 "Alkyl" refers to a straight or branched chain saturated hydrocarbon group having 1 to 6 carbon atoms. In some embodiments, C 1-4 Alkyl is preferred. In some embodiments, C 1-3 Alkyl is preferred. In some embodiments, C 1-2 Alkyl groups are preferred. 1-6 Examples of alkyl groups include: methyl (C1), ethyl (C2), n-propyl (C3), isopropyl (C3), n-butyl (C4), tert-butyl (C4), sec-butyl (C4), isobutyl (C4), n-pentyl (C5), 3-pentyl (C5), pentyl (C5), neopentyl (C5), 3-methyl-2-butyl (C5), tert-pentyl (C5), and n-hexyl (C6). The term “C 1-6 "Alkyl" also includes heteroalkyl groups in which one or more (e.g., 1, 2, 3, or 4) carbon atoms are replaced by heteroatoms (e.g., oxygen (O), sulfur (S), nitrogen (N), boron (B), silicon (Si), phosphorus (P)). The alkyl group may be optionally substituted with one or more substituents, for example, 1 to 5 substituents, 1 to 3 substituents, or 1 substituent. Conventional alkyl abbreviations include: Me (-CH3), Et (-CH2CH3), iPr (-CH(CH3)2), nPr (-CH2CH2CH3), n-Bu (-CH2CH2CH2CH3), or i-Bu (-CH2CH(CH3)2).

[0089] "Halo" or "halogen" refers to fluorine (F), chlorine (Cl), bromine (Br) and iodine (I).

[0090] "Deuterated" refers to deuterium (D).

[0091] Therefore, “C 1-6 "Haloalkyl" refers to the above-mentioned "C 1-6 Alkyl", which is substituted by one or more halogen groups. In some embodiments, C 1-3 Halogenated alkyl is particularly preferred, more preferably C 1-2Haloalkyl. Exemplary haloalkyl groups include, but are not limited to, -CF3, -CH2F, -CHF2, -CHFCH2F, -CH2CHF2, -CF2CF3, -CCl3, -CH2Cl, -CHCl2, 2,2,2-trifluoro-1,1-dimethyl-ethyl, and the like. The haloalkyl group can be substituted at any available point of attachment, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent.

[0092] “C 1-6 "Deuterated alkyl" refers to the above-mentioned "C 1-6 Alkyl", which is substituted with one or more deuterium (D). In some embodiments, C 1-3 Deuterated alkyl is particularly preferred, more preferably C 1-2 Deuterated alkyl. Exemplary haloalkyl groups include, but are not limited to, -CD3 and the like. The deuterated alkyl group may be substituted at any available point of attachment, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent.

[0093] “C 2-6 "Alkenyl" refers to a straight or branched chain hydrocarbon group having 2 to 6 carbon atoms and one or more carbon-carbon double bonds (e.g., 1, 2, or 3 carbon-carbon double bonds). The one or more carbon-carbon double bonds can be internal (e.g., in 2-butenyl) or terminal (e.g., in 1-butenyl). In some embodiments, C 2-4 Alkenyl is particularly preferred. Examples of the alkenyl include, but are not limited to, vinyl (C2), 1-propenyl (C3), 2-propenyl (C3), 1-butenyl (C4), 2-butenyl (C4), butadienyl (C4), pentenyl (C5), pentadienyl (C5), hexenyl (C6), and the like. Regardless of whether the alkenyl is modified with "substituted", each of the alkenyl groups is independently optionally substituted, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent, and suitable substituents are defined below.

[0094] “C 2-6 "Alkynyl" refers to a straight or branched chain hydrocarbon group having 2 to 6 carbon atoms, one or more carbon-carbon triple bonds (e.g., 1, 2, or 3 carbon-carbon triple bonds), and optionally one or more carbon-carbon double bonds (e.g., 1, 2, or 3 carbon-carbon double bonds). In some embodiments, C 2-4Alkynyl is particularly preferred. In some embodiments, alkynyl does not contain any double bond. One or more carbon triple bonds can be internal (e.g., in 2-butynyl) or end (e.g., in 1-butynyl). Examples of the alkynyl include, but are not limited to, ethynyl (C2), 1-propynyl (C3), 2-propynyl (C3), 1-butynyl (C4), 2-butynyl (C4), pentynyl (C5), hexynyl (C6), and the like. Regardless of whether "substituted" is modified before the alkynyl, each of the alkynyl groups is optionally substituted independently, e.g., 1 to 5 substituents, 1 to 3 substituents, or 1 substituent, and suitable substituents are defined as follows.

[0095] “C 1-6 Alkoxy" and "C 1-6 "Haloalkoxy" refers to -OR, wherein R is as above "C 1-6 Alkyl" and "C 1-6 "Haloalkyl" is defined.

[0096] “C 3-10 "Cycloalkyl" refers to a non-aromatic cyclic hydrocarbon group having 3 to 10 ring carbon atoms and zero heteroatoms. In some embodiments, C 3-8 Cycloalkyl, C 4-6 Cycloalkyl is preferred, C 3-6 Cycloalkyl is particularly preferred, more preferably C 5-6 Cycloalkyl. Cycloalkyl also includes ring systems in which the above-mentioned cycloalkyl ring is fused to one or more aryl or heteroaryl groups, wherein the point of attachment is on the cycloalkyl ring, and in such cases, the number of carbons continues to represent the number of carbons in the cycloalkyl system. Exemplary cycloalkyls include, but are not limited to, cyclopropyl (C3), cyclopropenyl (C3), cyclobutyl (C4), cyclobutenyl (C4), cyclopentyl (C5), cyclopentenyl (C5), cyclohexyl (C6), cyclohexenyl (C6), cyclohexadienyl (C6), cycloheptyl (C7), cycloheptenyl (C7), cycloheptadienyl (C7), cycloheptatrienyl (C7), cyclooctyl (C8), cyclooctenyl (C8), bicyclo[2.2.1]heptyl (C7), bicyclo[2.2.2]octyl (C8), cyclononyl (C9), cyclononenyl (C9), cyclodec ... 10 ), cyclodecenyl (C 10 ), octahydro-1H-indenyl (C9), decahydronaphthyl (C 10 ), spiro[4.5]decyl (C 10 ), bornyl, adamantyl, etc. Regardless of whether the cycloalkyl group is preceded by "substituted", each of the cycloalkyl groups is independently optionally substituted, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent, and suitable substituents are defined below.

[0097] "3-10 membered heterocyclyl" refers to a group of a 3- to 10-membered non-aromatic ring system having ring carbon atoms and 1 to 4 ring heteroatoms, wherein each heteroatom is independently selected from nitrogen, oxygen, sulfur, boron, phosphorus, and silicon. In heterocyclyl groups containing one or more nitrogen atoms, the point of attachment may be a carbon or nitrogen atom, as valence permits. In some embodiments, 4-10 membered heterocyclyl is preferred, which is a 4-10 membered non-aromatic ring system having ring carbon atoms and 1 to 4 ring heteroatoms; in some embodiments, 5-10 membered heterocyclyl is preferred, which is a 5-10 membered non-aromatic ring system having ring carbon atoms and 1 to 4 ring heteroatoms; in some embodiments, 3-8 membered heterocyclyl is preferred, which is a 3-8 membered non-aromatic ring system having ring carbon atoms and 1 to 3 ring heteroatoms; in some embodiments, 3-6 membered heterocyclyl is particularly preferred, which is a 3-6 membered non-aromatic ring system having ring carbon atoms and 1 to 3 ring heteroatoms; more preferably, 5-6 membered heterocyclyl is a 5-6 membered non-aromatic ring system having ring carbon atoms and 1 to 3 ring heteroatoms. Heterocyclyl also includes ring systems in which the above-mentioned heterocyclyl ring is fused to one or more cycloalkyl, aryl or heteroaryl groups, wherein the point of attachment is on the heterocyclyl ring; and in such cases, the number of ring members continues to represent the number of ring members in the heterocyclyl ring system. Regardless of whether the heterocyclyl group is preceded by "substituted", each of the heterocyclyl groups is independently optionally substituted, for example, with 1 to 5 substituents, 1 to 3 substituents or 1 substituent, suitable substituents being defined below.

[0098] Exemplary 3-membered heterocyclic groups containing one heteroatom include, but are not limited to, aziridine, oxirane, and thiorenyl. Exemplary 4-membered heterocyclic groups containing one heteroatom include, but are not limited to, azetidinyl, oxetane, and thietanyl. Exemplary 5-membered heterocyclic groups containing one heteroatom include, but are not limited to, tetrahydrofuranyl, dihydrofuranyl, tetrahydrothienyl, dihydrothienyl, pyrrolidinyl, dihydropyrrolyl, and pyrrolyl-2,5-dione. Exemplary 5-membered heterocyclic groups containing two heteroatoms include, but are not limited to, dioxolanyl, oxasulfuranyl, disulfuranyl, and oxazolidin-2-one. Exemplary 5-membered heterocyclic groups containing three heteroatoms include, but are not limited to, triazolinyl, oxadiazolinyl, and thiadiazolinyl. Exemplary 6-membered heterocyclyls containing one heteroatom include, but are not limited to, piperidinyl, tetrahydropyranyl, dihydropyridinyl, and thianyl. Exemplary 6-membered heterocyclyls containing two heteroatoms include, but are not limited to, piperazinyl, morpholinyl, dithianyl, and dioxanyl. Exemplary 6-membered heterocyclyls containing three heteroatoms include, but are not limited to, hexahydrotriazinyl. Exemplary 7-membered heterocyclyls containing one heteroatom include, but are not limited to, azepanyl, oxepanyl, and thiepanyl. Exemplary 8-membered heterocyclyls containing one heteroatom include, but are not limited to, azocanyl, oxepanyl, and thiocanyl. Exemplary 5-membered heterocyclyls fused to a C6 aryl ring (also referred to herein as 5,6-bicyclic heterocyclyls) include, but are not limited to, dihydroindolinyl, isoindolinyl, dihydrobenzofuranyl, dihydrobenzothienyl, benzoxazolinyl, and the like. Exemplary 6-membered heterocyclyl groups (also referred to herein as 6,6-bicyclic heterocyclyl groups) fused to a C6 aryl ring include, but are not limited to, tetrahydroquinolinyl, tetrahydroisoquinolinyl, and the like.

[0099] “C 6-10 "Aryl" refers to a monocyclic or polycyclic (e.g., bicyclic or tricyclic) 4n+2 aromatic ring system (e.g., having 6 or 10 π electrons shared in a cyclic arrangement) having 6-10 ring carbon atoms and zero heteroatoms. In some embodiments, an aryl group has six ring carbon atoms ("C6 aryl"; e.g., phenyl). In some embodiments, an aryl group has ten ring carbon atoms ("C 10 "aryl"; e.g., naphthyl, e.g., 1-naphthyl and 2-naphthyl). In some embodiments, C 6-10Aryl is particularly preferred, with C6 aryl being more preferred. Aryl also includes ring systems in which the aforementioned aryl ring is fused to one or more cycloalkyl or heterocyclic groups, with the point of attachment being on the aryl ring. In this case, the number of carbon atoms continues to represent the number of carbon atoms in the aryl ring system. Regardless of whether the aryl group is preceded by "substituted," each aryl group is independently optionally substituted, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent. Suitable substituents are defined below.

[0100] "5-10 membered heteroaryl" refers to a group of a 5-10 membered monocyclic or bicyclic 4n+2 aromatic ring system (e.g., having 6 or 10 π electrons shared in a cyclic arrangement) having ring carbon atoms and 1-4 ring heteroatoms, wherein each heteroatom is independently selected from nitrogen, oxygen, and sulfur. In heteroaryl groups containing one or more nitrogen atoms, the point of attachment may be a carbon or nitrogen atom as long as valence permits. Heteroaryl bicyclic ring systems may include one or more heteroatoms in one or both rings. Heteroaryl also includes ring systems in which the above-mentioned heteroaryl rings are fused to one or more cycloalkyl or heterocyclyl groups, and the point of attachment is on the heteroaryl ring, in which case the number of carbon atoms continues to represent the number of carbon atoms in the heteroaryl ring system. In some embodiments, 5-6 membered heteroaryl is particularly preferred, which is a 5-6 membered monocyclic or bicyclic 4n+2 aromatic ring system having ring carbon atoms and 1-4 ring heteroatoms. In some embodiments, 5-membered heteroaryl is particularly preferred, which is a 5-membered monocyclic or bicyclic 4n+2 aromatic ring system having ring carbon atoms and 1-4 ring heteroatoms. Regardless of whether the heteroaryl group is preceded by "substituted", each of the heteroaryl groups is independently optionally substituted, for example, with 1 to 5 substituents, 1 to 3 substituents, or 1 substituent, and suitable substituents are defined below.

[0101] Exemplary 5-membered heteroaryl groups containing one heteroatom include, but are not limited to, pyrrolyl, furanyl, and thienyl. Exemplary 5-membered heteroaryl groups containing two heteroatoms include, but are not limited to, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, and isothiazolyl. Exemplary 5-membered heteroaryl groups containing three heteroatoms include, but are not limited to, triazolyl, oxadiazolyl, and thiadiazolyl. Exemplary 5-membered heteroaryl groups containing four heteroatoms include, but are not limited to, tetrazolyl. Exemplary 6-membered heteroaryl groups containing one heteroatom include, but are not limited to, pyridinyl. Exemplary 6-membered heteroaryl groups containing two heteroatoms include, but are not limited to, pyridazinyl, pyrimidinyl, and pyrazinyl. Exemplary 6-membered heteroaryl groups containing three or four heteroatoms include, but are not limited to, triazinyl and tetrazinyl, respectively. Exemplary 7-membered heteroaryl groups containing one heteroatom include, but are not limited to, azepine, oxepinyl, and thiepine. Exemplary 5,6-bicyclic heteroaryl groups include, but are not limited to, indolyl, isoindolyl, indazolyl, benzotriazolyl, benzothiophenyl, isobenzothiophenyl, benzofuranyl, benzisofuranyl, benzimidazolyl, benzoxazolyl, benzisoxazolyl, benzoxadiazolyl, benzothiazolyl, benzisothiazolyl, benzothiadiazolyl, indanyl, and purinyl. Exemplary 6,6-bicyclic heteroaryl groups include, but are not limited to, naphthyridinyl, pteridinyl, quinolinyl, isoquinolinyl, cinnolinyl, quinoxalinyl, phthalazinyl, and quinazolinyl.

[0102] In this application, the term "optional" or "optionally" generally means that the subsequently described event or circumstance can but need not occur, and the description includes instances where the event or circumstance occurs or does not occur. For example, "a heterocyclic group optionally substituted with an alkyl group" means that the alkyl group can but need not be present, and the description includes instances where the heterocyclic group is substituted with an alkyl group and instances where the heterocyclic group is not substituted with an alkyl group.

[0103] Exemplary substituents on carbon atoms include, but are not limited to, halogen, -CN, -NO2, -N3, -SO2H, -SO3H, -OH, -OR aa 、-ON(R bb )2、-N(R bb )2、-N(R bb )3 + X - 、-N(OR cc )R bb 、-SH、-SR aa 、-SSR cc 、-C(=O)R aa 、-CO2H、-CHO、-C(OR cc )2, -CO2R aa 、-OC(=O)R aa 、-OCO2R aa、-C(=O)N(R bb )2、-OC(=O)N(R bb )2、-NR bb C(=O)R aa 、-NR bb CO2R aa 、-NR bb C(=O)N(R bb )2、-C(=NR bb )R aa 、-C(=NR bb )OR aa 、-OC(=NR bb )R aa 、-OC(=NR bb )OR aa 、-C(=NR bb )N(R bb )2、-OC(=NR bb )N(R bb )2、-NR bb C(=NR bb )N(R bb )2、-C(=O)NR bb SO2R aa 、-NR bb SO2R aa 、-SO2N(R bb )2、-SO2R aa 、-SO2OR aa 、-OSO2R aa 、-S(=O)R aa 、-OS(=O)R aa 、-Si(R aa )3、-OSi(R aa )3、-C(=S)N(R bb )2、-C(=O)SR aa 、-C(=S)SR aa 、-SC(=S)SR aa 、-SC(=O)SR aa 、-OC(=O)SR aa 、-SC(=O)OR aa 、-SC(=O)R aa 、-P(=O)2R aa 、-OP(=O)2R aa 、-P(=O)(R aa )2、-OP(=O)(R aa )2、-OP(=O)(OR cc )2、-P(=O)2N(Rbb )2、-OP(=O)2N(R bb )2、-P(=O)(NR bb )2、-OP(=O)(NR bb )2、-NR bb P(=O)(OR cc )2、-NR bb P(=O)(NR bb )2、-P(R cc )2、-P(R cc )3、-OP(R cc )2、-OP(R cc )3、-B(R aa )2、-B(OR cc )2, -BR aa (OR cc ), alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl is independently replaced by 0, 1, 2, 3, 4 or 5 R dd group substitution;

[0104] Or the two geminal hydrogen atoms on the carbon atom are replaced by groups =O, =S, =NN(R bb )2, =NNR bb C(=O)R aa 、=NNR bb C(=O)OR aa 、=NNR bb S(=O)2R aa 、=NR bb or = NOR cc replace;

[0105] R aa Each of R is independently selected from alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl, or two R aa The groups are combined to form a heterocyclic or heteroaryl ring, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl group is independently replaced by 0, 1, 2, 3, 4 or 5 R dd group substitution;

[0106] R bb Each of the following is independently selected from: hydrogen, -OH, -OR aa 、-N(R cc )2, -CN, -C(=O)R aa 、-C(=O)N(R cc )2, -CO2R aa 、-SO2R aa 、-C(=NRcc )OR aa 、-C(=NR cc )N(R cc )2、-SO2N(R cc )2, -SO2R cc 、-SO2OR cc 、-SOR aa 、-C(=S)N(R cc )2, -C(=O)SR cc 、-C(=S)SR cc 、-P(=O)2R aa 、-P(=O)(R aa )2、-P(=O)2N(R cc )2、-P(=O)(NR cc )2, alkyl, haloalkyl, alkenyl, alkynyl, carbocyclic, heterocyclic, aryl and heteroaryl, or two R bb The groups are combined to form a heterocyclic or heteroaryl ring, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl group is independently replaced by 0, 1, 2, 3, 4 or 5 R dd group substitution;

[0107] R cc Each of R is independently selected from hydrogen, alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl, or two R cc The groups are combined to form a heterocyclic or heteroaryl ring, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl group is independently replaced by 0, 1, 2, 3, 4 or 5 R dd group substitution;

[0108] R dd Each of the is independently selected from: halogen, -CN, -NO2, -N3, -SO2H, -SO3H, -OH, -OR ee 、-ON(R ff )2、-N(R ff )2,、-N(R ff )3 + X - 、-N(OR ee )R ff 、-SH、-SR ee 、-SSR ee 、-C(=O)R ee 、-CO2H、-CO2R ee 、-OC(=O)R ee 、-OCO2R ee 、-C(=O)N(R ff )2、-OC(=O)N(Rff )2、-NR ff C(=O)R ee 、-NR ff CO2R ee 、-NR ff C(=O)N(R ff )2、-C(=NR ff )OR ee 、-OC(=NR ff )R ee 、-OC(=NR ff )OR ee 、-C(=NR ff )N(R ff )2、-OC(=NR ff )N(R ff )2、-NR ff C(=NR ff )N(R ff )2、-NR ff SO2R ee 、-SO2N(R ff )2, -SO2R ee 、-SO2OR ee 、-OSO2R ee 、-S(=O)R ee 、-Si(R ee )3、-OSi(R ee )3、-C(=S)N(R ff )2, -C(=O)SR ee 、-C(=S)SR ee 、-SC(=S)SR ee 、-P(=O)2R ee 、-P(=O)(R ee )2、-OP(=O)(R ee )2、-OP(=O)(OR ee )2, alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl, heteroaryl, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl is independently substituted by 0, 1, 2, 3, 4 or 5 R gg Group substitution, or two geminal R dd Substituents may combine to form =O or =S;

[0109] R ee Each of R is independently selected from alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, aryl, heterocyclyl and heteroaryl, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl is independently replaced by 0, 1, 2, 3, 4 or 5 R gg group substitution;

[0110] R ff Each of R is independently selected from hydrogen, alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl, or two R ff The groups are combined to form a heterocyclic or heteroaryl ring, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl group is independently replaced by 0, 1, 2, 3, 4 or 5 R gg group substitution;

[0111] R gg Each of the independently: halogen, -CN, -NO2, -N3, -SO2H, -SO3H, -OH, -OC 1-6 Alkyl, -ON(C 1-6 Alkyl)2, -N(C 1-6 Alkyl)2, -N(C 1-6 Alkyl)3 + X - 、-NH(C 1-6 Alkyl)2 + X - 、-NH2(C 1-6 alkyl) + X - 、-NH3 + X - 、-N(OC 1-6 Alkyl)(C 1-6 Alkyl), -N(OH)(C 1-6 Alkyl), -NH(OH), -SH, -SC 1-6 Alkyl, -SS(C 1-6 alkyl), -C(=O)(C 1-6 alkyl), -CO2H, -CO2(C 1-6 alkyl), -OC(=O)(C 1-6 Alkyl), -OCO2(C 1-6 alkyl), -C(=O)NH2, -C(=O)N(C 1-6 alkyl)2, -OC(=O)NH(C 1-6 alkyl), -NHC(=O)(C 1-6 Alkyl), -N(C 1-6 alkyl)C(=O)(C 1-6 Alkyl), -NHCO2(C 1-6 alkyl), -NHC(=O)N(C 1-6 alkyl)2, -NHC(=O)NH(C 1-6 alkyl), -NHC(=O)NH2, -C(=NH)O(C 1-6 alkyl), -OC(=NH)(C 1-6alkyl), -OC(=NH)OC 1-6 Alkyl, -C(=NH)N(C 1-6 Alkyl)2, -C(=NH)NH(C 1-6 alkyl), -C(=NH)NH2, -OC(=NH)N(C 1-6 Alkyl)2, -OC(NH)NH(C 1-6 alkyl), -OC(NH)NH2, -NHC(NH)N(C 1-6 Alkyl)2, -NHC(=NH)NH2, -NHSO2(C 1-6 Alkyl), -SO2N(C 1-6 Alkyl)2, -SO2NH(C 1-6 alkyl), -SO2NH2, -SO2C 1-6 Alkyl, -SO2OC 1-6 Alkyl, -OSO2C 1-6 Alkyl, -SOC 1-6 Alkyl, -Si(C 1-6 alkyl)3, -OSi(C 1-6 alkyl)3, -C(=S)N(C 1-6 alkyl)2、C(=S)NH(C 1-6 alkyl), C(=S)NH2, -C(=O)S(C 1-6 alkyl), -C(=S)SC 1-6 Alkyl, -SC(=S)SC 1-6 Alkyl, -P(=O)2(C 1-6 alkyl), -P(=O)(C 1-6 alkyl)2, -OP(=O)(C 1-6 alkyl)2, -OP(=O)(OC 1-6 Alkyl)2, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C3-C7 carbocyclic group, C6-C 10 Aryl, C3-C7 heterocyclic, C5-C 10 heteroaryl; or two geminal R gg Substituents may combine to form =O or =S; wherein X - For the counter ion.

[0112] Exemplary substituents on nitrogen atoms include, but are not limited to, hydrogen, -OH, -OR aa 、-N(R cc )2, -CN, -C(=O)R aa 、-C(=O)N(R cc )2, -CO2R aa 、-SO2Raa 、-C(=NR bb )R aa 、-C(=NR cc )OR aa 、-C(=NR cc )N(R cc )2、-SO2N(R cc )2, -SO2R cc 、-SO2OR cc 、-SOR aa 、-C(=S)N(R cc )2, -C(=O)SR cc 、-C(=S)SR cc 、-P(=O)2R aa 、-P(=O)(R aa )2、-P(=O)2N(R cc )2、-P(=O)(NR cc )2, alkyl, haloalkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl, or two R attached to the nitrogen atom cc The groups are combined to form a heterocyclic or heteroaryl ring, wherein each alkyl, alkenyl, alkynyl, carbocyclyl, heterocyclyl, aryl and heteroaryl group is independently replaced by 0, 1, 2, 3, 4 or 5 R dd group substituted, and wherein R aa 、R bb 、R cc and R dd As mentioned above.

[0113] "Deuterated" or "deuterium" refers to a compound or group in which one or more hydrogen atoms are replaced by deuterium; deuteration can be mono-, di-, poly-, or per-substituted. The terms "one or more deuterated" and "one or more deuterated" are used interchangeably. The deuterium isotope content of deuterium at the deuterated position is at least 0.015% greater than the natural deuterium isotope content, preferably greater than 30%, more preferably greater than 50%, more preferably greater than 75%, more preferably greater than 95%, and even more preferably greater than 99%.

[0114] As used herein, the term "compound of the present application" refers to the compound of the present application. The term also includes various stereoisomers, enantiomers, diastereomers, meso-racemates, racemates or tautomers of the compound of the present application.

[0115] Biological definition

[0116] The "nucleobase" in this application can be either a natural nucleobase or a modified nucleobase. Natural nucleobases include, but are not limited to, adenine (A), guanine (G), cytosine (C), uracil (U), thymine (T), and any one of their derivatives.

[0117] "Modified nucleoside base" refers to a substance obtained by replacing one or more hydrogen atoms of a natural nucleoside base, including but not limited to N6-methyladenine, N1-methyladenine, N6-2'-O-dimethyladenosine, pseudouridine, N1-methylpseudouridine, 5-iodouridine, 4-thiouridine, 2-thiouridine, 5-methyluridine, pseudoisocytosine, 5-methoxycytosine, 2-thiouridine, 5-hydroxycytosine, N1-methylcytosine, 5-hydroxymethylcytosine, hypoxanthine, N1-methylguanine, isoguanine, etc.

[0118] Other definitions

[0119] In this application, the term "comprising" generally refers to including the features explicitly specified but not excluding other elements. The terms "above" and "below" generally refer to including the number specified.

[0120] In this application, the term "about" generally refers to a variation within a range of 0.5%-10% above or below the specified value, for example, a variation within a range of 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10% above or below the specified value.

[0121] As used herein, the term "pharmaceutically acceptable salt" means an acid addition salt or a base addition salt of the compounds of the invention which are suitable for use in contact with the tissues of patients, within the scope of sound medical judgment, do not produce undue toxicity, irritation, allergic response, or the like, commensurate with a reasonable benefit / risk ratio, and are effective for their intended use, including, where possible, zwitterionic forms of the compounds of the invention.

[0122] Pharmaceutically acceptable salts can be sulfates, pyrosulfates, bisulfates, sulfites, bisulfites, nitrates, borates, phosphates, monohydrogen phosphates, dihydrogen phosphates, metaphosphates, pyrophosphates, chlorides, bromides, iodides, and the like, prepared from inorganic acids. Representative salts include hydrobromides, hydrochlorides, sulfates, bisulfates, nitrates, borates, and phosphates. Salts can also be prepared from organic acids, such as aliphatic mono- and dicarboxylic acids, phenyl-substituted alkanoic acids, hydroxyalkanoic acids, alkanedioic acids, aromatic acids, and aliphatic and aromatic sulfonic acids. Representative salts include acetate, propionate, valerate, oleate, palmitate, stearate, laurate, octanoate, isobutyrate, oxalate, malonate, succinate, suberate, sebacate, fumarate, mandelate, benzoate, chlorobenzoate, methylbenzoate, dinitrobenzoate, naphthoate, benzenesulfonate, toluenesulfonate, phenylacetate, citrate, lactate, maleate, tartrate, methanesulfonate, glucoheptonate, lactobionate, laurylsulfonate, and isethionate, etc. Pharmaceutically acceptable salts may include cations based on alkali and alkaline earth metals, such as sodium, lithium, potassium, calcium, magnesium, and the like, as well as non-toxic ammonium, quaternary ammonium, and amine cations, including, but not limited to, ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, ethylamine, and the like. Also contemplated are salts of amino acids, such as argininate, gluconate, galacturonate, and the like (see, e.g., Berge SM et al., "Pharmaceutical Salts," J. Pharm. Sci., 1977; 66: 1-19, incorporated herein by reference).

[0123] The present invention also includes isotopically labeled compounds (isotopic variants) which are identical to those of the general formulae or specific compounds described herein, but for the fact that one or more atoms are replaced by an atom having an atomic mass or mass number different from the atomic mass or mass number usually found in nature. Examples of isotopes that can be incorporated into the compounds of the present invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, and chlorine, for example, 2 H. 3 H. 13 C. 11 C. 14 C. 15 N. 18 O. 17 O. 31 P. 32 P. 35 S. 18 F and 36Cl. Compounds of the present invention containing the above-mentioned isotopes and / or other isotopes of other atoms, their prodrugs and pharmaceutically acceptable salts of the compounds or prodrugs are within the scope of the present invention. Certain isotopically labeled compounds of the present invention, such as those in which radioactive isotopes (e.g. 3 H and 14 C) can be used in drug and / or substrate tissue distribution assays. 3 H and carbon-14, i.e. 14 C isotopes are particularly preferred because they are easy to prepare and detect. In addition, heavier isotopes such as deuterium (i.e. 2 H) substitution may be preferred in some cases because greater metabolic stability may provide therapeutic benefits, such as increased in vivo half-life or reduced dosage requirements. Isotopically labeled compounds of the present invention and prodrugs thereof can generally be prepared by substituting readily available isotopically labeled reagents for non-isotopically labeled reagents when performing the processes disclosed in the following schemes and / or the Examples and Preparations.

[0124] The compounds of the present invention include one or more asymmetric centers and may therefore exist in a variety of stereoisomeric forms, for example, enantiomers and / or diastereomeric forms. For example, the compounds of the present invention may be individual enantiomers, diastereomers, or geometric isomers (e.g., cis and trans isomers), or may be in the form of mixtures of stereoisomers, including racemic mixtures and mixtures enriched in one or more stereoisomers. Isomers may be separated from the mixture by methods known to those skilled in the art, including chiral high pressure liquid chromatography (HPLC) and the formation and crystallization of chiral salts; or preferred isomers may be prepared by asymmetric synthesis.

[0125] As used herein, the term "pharmaceutical composition" generally refers to a mixture containing one or more compounds described herein, or their physiologically / pharmaceutically acceptable salts or prodrugs, and other chemical components, as well as other components such as physiologically / pharmaceutically acceptable carriers and excipients. Pharmaceutical compositions can facilitate administration to an organism, facilitating absorption of the active ingredient and thereby exerting its biological activity. Conventional pharmaceutical compositions can be prepared using techniques commonly used in the art.

[0126] In this application, the term "pharmaceutically acceptable carrier" generally refers to a carrier for administering therapeutic agents, such as antibodies or polypeptides, genes and other therapeutic agents. The term refers to any pharmaceutical carrier that does not itself induce the production of antibodies harmful to the individual receiving the composition and can be administered without excessive toxicity. For example, a pharmaceutically acceptable carrier can be distinguished from a nucleic acid vector used to contain a gene in genetic engineering. Suitable carriers can be large, slowly metabolized macromolecules, such as proteins, polysaccharides, polylactic acid, polyglycolic acid, polyamino acids, amino acid copolymers, lipid aggregates and inactivated viral particles. These carriers are well known to those skilled in the art. Pharmaceutically acceptable carriers in therapeutic compositions may include liquids, such as water, saline, glycerol and ethanol. Auxiliary substances, such as wetting agents or emulsifiers, pH buffer substances, etc., may also be present in these carriers.

[0127] As used herein, the term "effective amount" generally refers to an amount of a therapeutic agent that treats, alleviates, or prevents a target disease or condition, or an amount that exhibits a detectable therapeutic or preventive effect. The precise effective amount for a given subject depends on the subject's size and health, the nature and extent of the condition, and the therapeutic agent and / or combination of therapeutic agents selected for administration. Therefore, it is not useful to specify an exact effective amount in advance. However, for a given condition, the effective amount can be determined by routine experimentation, which is within the judgment of the clinician.

[0128] The term "patient" includes both mammals and non-mammals. Examples of mammals include, but are not limited to, any member of the class Mammalia: humans, non-human primates such as chimpanzees and other apes and monkeys; farm animals such as cattle, horses, sheep, goats, and pigs; domestic animals such as rabbits, dogs, and cats; laboratory animals, including rodents such as rats, mice, and guinea pigs, and including unborn mammals. Examples of non-mammals include, but are not limited to, birds, fish, and the like.

[0129] The term "patient" includes confirmed patients, but the "patient" does not need to have any special identity with respect to the hospital, clinic or research facility (such as being a confirmed patient, research participant, etc.). Specific implementation plan

[0130] In one aspect, the present invention provides a compound of formula (I'), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0131] in,

[0132] R X1 OR a ;

[0133] R X2OR b ;

[0134] W is selected from O or S;

[0135] R1 is selected from halogen or OR c ;

[0136] R'1 is selected from H or halogen;

[0137] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0138] R'2 is selected from H or halogen;

[0139] R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ;

[0140] R4 is selected from halogen, OR f or

[0141] R5 is selected from halogen or OR g ;

[0142] R6 is selected from halogen or OR h ;

[0143] R7 is selected from halogen or OR i ;

[0144] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CHO, OCH2, CH2CH2O, OCH2CH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2; and at least one of the following conditions is met:

[0145] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0146] 2) X1 is CH2CH2O, OCH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2,

[0147] 3) X2 is OCH2CH2, CH2O, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2;

[0148] 4) X3 is OCH2CH2;

[0149] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0150] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0151] R' is selected from H or halogen;

[0152] or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0153] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0154] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0155] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6haloalkoxy substitution;

[0156] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, preferably deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, preferably deuterium.

[0157] In one aspect, the present invention provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0158] in,

[0159] R X1 OR a ;

[0160] R X2 OR b ;

[0161] W is selected from O or S;

[0162] R1 is selected from halogen or OR c ;

[0163] R2 is selected from halogen or OR d ;

[0164] R3 is selected from halogen or OR e ;

[0165] R4 is selected from halogen, OR f or

[0166] R5 is selected from halogen or OR g ;

[0167] R6 is selected from halogen or OR h ;

[0168] R7 is selected from halogen or OR i ;

[0169] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0170] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0171] 2) X1 is CH2CH2O,

[0172] 3) X2 is OCH2CH2;

[0173] 4) X3 is OCH2CH2;

[0174] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0175] R and R' are selected from H or halogen;

[0176] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0177] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0178] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6haloalkoxy substitution;

[0179] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0180] In one aspect, the present invention also provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0181] in,

[0182] X1, X2 and X3 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0183] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0184] 2) X1 is CH2CH2O,

[0185] 3) X2 is OCH2CH2;

[0186] R X1 OR a ;

[0187] R X2 OR b ;

[0188] W is selected from O or S;

[0189] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2;

[0190] R1 is selected from halogen or OR c ;

[0191] R2 is selected from halogen or OR d ;

[0192] R3 is selected from halogen or OR e ;

[0193] R4 is selected from halogen or OR f ;

[0194] R5 is selected from halogen or OR g ;

[0195] R and R' are selected from H or halogen;

[0196] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0197] B1, B2 and B3 are independently selected from natural, modified or unnatural nucleobases;

[0198] R a 、R b 、R c 、R d 、R e 、R f and R g independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0199] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0200] X1, X2, X3 and X4

[0201] In one embodiment, X1 is O; in another embodiment, X1 is S; in another embodiment, X1 is CH2; in another embodiment, X1 is CH2CH2; in another embodiment, X1 is CH═CH; in another embodiment, X1 is CHO; in another embodiment, X1 is OCH2; in another embodiment, X1 is CH2CH2O; in another embodiment, X1 is OCH2CH2; in another embodiment, X1 is C(═CH2)CH2; in another embodiment, X1 is CH2C(═CH2); in another embodiment, X1 is C(O)CH2; in another embodiment, X1 is C(S)CH2.

[0202] In one embodiment, X2 is O; in another embodiment, X2 is S; in another embodiment, X2 is CH2; in another embodiment, X2 is CH2CH2; in another embodiment, X2 is CH═CH; in another embodiment, X2 is CHO; in another embodiment, X2 is OCH2; in another embodiment, X2 is CH2CH2O; in another embodiment, X2 is OCH2CH2; in another embodiment, X2 is C(═CH2)CH2; in another embodiment, X2 is CH2C(═CH2); in another embodiment, X2 is C(O)CH2; in another embodiment, X2 is C(S)CH2.

[0203] In one embodiment, X3 is O; in another embodiment, X3 is S; in another embodiment, X3 is CH2; in another embodiment, X3 is CH2CH2; in another embodiment, X3 is CH═CH; in another embodiment, X3 is CHO; in another embodiment, X3 is OCH2; in another embodiment, X3 is CH2CH2O; in another embodiment, X3 is OCH2CH2; in another embodiment, X3 is C(═CH2)CH2; in another embodiment, X3 is CH2C(═CH2); in another embodiment, X3 is C(O)CH2; in another embodiment, X1 is C(S)CH2.

[0204] X1, X2 and X3 must meet at least one of the following conditions:

[0205] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0206] 2) X1 is CH2CH2O,

[0207] 3) X2 is OCH2CH2.

[0208] In one embodiment, X4 is O; in another embodiment, X4 is S; in another embodiment, X4 is CH2; in another embodiment, X4 is CH2CH2; in another embodiment, X4 is CH═CH; in another embodiment, X4 is CH2O; in another embodiment, X4 is OCH2; in another embodiment, X4 is CH2CH2O; in another embodiment, X4 is OCH2CH2.

[0209] X1, X2, X3 and X4 must meet at least one of the following conditions:

[0210] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0211] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0212] 2) X1 is CH2CH2O,

[0213] 3) X2 is OCH2CH2;

[0214] 4) X3 is OCH2CH2.

[0215] X1, X2, X3 and X4 must meet at least one of the following conditions:

[0216] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0217] 2) X1 is CH2CH2O, OCH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2,

[0218] 3) X2 is OCH2CH2, CH2O, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2;

[0219] 4) X3 is OCH2CH2.

[0220] In one embodiment, X1 is selected from O, S or CH2; in another embodiment, X1 is selected from O, CH2, CH2CH2, CH═CH, CHO, OCH2, CH2CH2O, C(═CH2)CH2, CH2C(═CH2), C(O)CH2 or C(S)CH2; in another embodiment, X1 is selected from O, CH2, CH2CH2, CH═CH, CHO, OCH2 or CH2CH2O; in another embodiment, X1 is selected from CH2, CH2CH2, CHO, OCH2 or CH2CH2O.

[0221] In one embodiment, X2 is selected from O, S or CH2; in another embodiment, X2 is selected from CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2; in another embodiment, X2 is selected from CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2.

[0222] In one embodiment, X3 is selected from O, S or CH2; in another embodiment, X3 is selected from CH2, CH2CH2, OCH2 or OCH2CH2.

[0223] W

[0224] In one embodiment, W is O; in another embodiment, W is S.

[0225] Y1, Y2, Y3 and Y4

[0226] In one embodiment, Y1 is O; in another embodiment, Y1 is S; in another embodiment, Y1 is NH; in another embodiment, Y1 is CH2.

[0227] In one embodiment, Y2 is O; in another embodiment, Y2 is S; in another embodiment, Y2 is NH; in another embodiment, Y2 is CH2.

[0228] In one embodiment, Y3 is O; in another embodiment, Y3 is S; in another embodiment, Y3 is NH; in another embodiment, Y3 is CH2.

[0229] In one embodiment, Y4 is O; in another embodiment, Y4 is S; in another embodiment, Y4 is NH; in another embodiment, Y4 is CH2.

[0230] In one embodiment, at least one of Y1, Y2 and Y3 is CH2; in another embodiment, Y1 is CH2 and Y2 and Y3 are O; in another embodiment, Y2 is CH2 and Y1 and Y3 are O; in another embodiment, Y3 is CH2 and Y1 and Y2 are O; in another embodiment, Y1 and Y2 are CH2 and Y3 is O; in another embodiment, at least one of Y1, Y2, Y3 and Y4 is CH2; in another embodiment, At least one is O, S or NH; in another embodiment, one of Y1, Y2 and Y3 is O, S or NH; in another embodiment, at least one of Y1, Y2, Y3 and Y4 is O, S or NH; in another embodiment, Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y2 and Y3 are O; in another embodiment, Y1 and Y3 are O; in another embodiment, Y3 is O; in another embodiment, Y4 is O.

[0231] R1, R2, R3, R4, R5, R6, and R7

[0232] In one embodiment, R1 is halogen, such as F; in another embodiment, R1 is OR c , such as OH.

[0233] In one embodiment, R2 is halogen, such as F; in another embodiment, R2 is C 1-6 Alkyl, preferably C 1-3 Alkyl; in another embodiment, R2 is C 1-6 Halogenated alkyl, preferably C 1-3 Haloalkyl, such as CH2F or CF2H; in another embodiment, R2 is OR d , such as OH, OMe, OCD3 or OCH2CH2OMe; in another embodiment, R2 is optionally substituted by 1 group selected from the following: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 In another embodiment, R2 is optionally substituted with 1 group selected from the group consisting of: C 1-6 Alkoxy or C 1-6 Halogenated alkoxy, preferably C1-3 Alkoxy or C 1-3 Haloalkoxy, such as CH2OCH3; In another embodiment, R2 is optionally substituted by a group selected from the group consisting of: NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Haloalkyl, such as CH2NHC(O)CH3; in another embodiment, R2 is unsubstituted.

[0234] In one embodiment, R2 is OH or C 1-6 Alkoxy (eg, OMe); in another embodiment, R2 is F, OH, C 1-6 Alkoxy or C 1-6 In another embodiment, R2 is OH, C 1-6 Alkoxy or C 1-6 In another embodiment, R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d In another embodiment, R2 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d In another embodiment, R2 is selected from halogen or OR d .

[0235] In one embodiment, R3 is halogen, such as F; in another embodiment, R3 is C 1-6 Alkyl, preferably C 1-3 Alkyl; in another embodiment, R3 is C 1-6 Halogenated alkyl, preferably C 1-3 Haloalkyl, such as CH2F or CF2H; in another embodiment, R3 is OR e , such as OH, OMe or OEt, such as OH, OMe, OEt or OCH2CH2OMe, such as OMe, OEt or OCH2CH2OMe, such as OCH3, OCH2CH3, OCH2CH2OCH3, OCD3 or OCF3, preferably OMe.

[0236] In one embodiment, R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C1-6 Haloalkoxy substitution.

[0237] In one embodiment, R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e In another embodiment, R3 is selected from F or OR e In another embodiment, R3 is selected from OR e ; F or C 1-6 Alkoxy; In another embodiment, R3 is C 1-6 Alkoxy (eg, OMe); in another embodiment, R' and R3 are optionally linked to form CH2O or CH2CH2O, preferably CH2O.

[0238] In one embodiment, R4 is halogen, such as F; in another embodiment, R4 is OR f , such as OH; in another embodiment, R4 is For example

[0239] In one embodiment, R5 is halogen, such as F; in another embodiment, R5 is OR g , such as OH.

[0240] In one embodiment, R6 is halogen, such as F; in another embodiment, R6 is OR h , such as OH.

[0241] In one embodiment, R7 is halogen, such as F; in another embodiment, R7 is OR i , such as OH.

[0242] R and R'

[0243] In one embodiment, R is H; in another embodiment, R is halogen.

[0244] In one embodiment, R' is H; in another embodiment, R' is halogen.

[0245] In one embodiment, R and R1 are linked to form CHO; in another embodiment, R and R1 are linked to form OCH2; in another embodiment, R and R1 are linked to form CH2CH2O; in another embodiment, R and R1 are linked to form OCH2CH2; in another embodiment, R and R1 are not linked.

[0246] In one embodiment, R' and R3 are linked to form CHO; in another embodiment, R' and R3 are linked to form OCH2; in another embodiment, R' and R3 are linked to form CH2CH2O; in another embodiment, R' and R3 are linked to form OCH2CH2; in another embodiment, R' and R3 are not linked.

[0247] In one embodiment, R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably OCH2 or OCH2CH2.

[0248] In one embodiment, R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O.

[0249] B1, B2, B3 and B4

[0250] In one embodiment, B1, B2 and B3 are independently selected from natural nucleoside bases, such as adenine (A), guanine (G), cytosine (C), uracil (U) and thymine (T); in another embodiment, B1, B2 and B3 are independently selected from modified nucleoside bases, such as N6-methyladenine, N1-methyladenine, N6-2'-O-dimethyladenosine, pseudouridine, N1-methylpseudouridine, 5-iodouridine, 4-thiouridine, 2-thiouridine, 5-methyluridine, pseudoisocytosine, 5-methoxycytosine, 2-thiouridine, 5-hydroxycytosine, N1-methylcytosine, 5-hydroxymethylcytosine, hypoxanthine, N1-methylguanine, isoguanine, etc.; in another embodiment, B1, B2 and B3 are independently selected from non-natural nucleoside bases.

[0251] In one embodiment, B1, B2, B3 and B4 are independently selected from natural nucleoside bases, such as adenine (A), guanine (G), cytosine (C), uracil (U) and thymine (T); in another embodiment, B1, B2, B3 and B4 are independently selected from modified nucleoside bases, such as N6-methyladenine, N1-methyladenine, N6-2′-O-dimethyladenosine, pseudouridine, N1-methylpseudouridine, 5-iodouridine, 4-thiouridine, 2-thiouridine, 5-methyluridine, pseudoisocytosine, 5-methoxycytosine, 2-thiouridine, 5-hydroxycytosine, N1-methylcytosine, 5-hydroxymethylcytosine, hypoxanthine, N1-methylguanine, isoguanine, etc.; in another embodiment, B1, B2, B3 and B4 are independently selected from non-natural nucleoside bases.

[0252] In one embodiment, B1 is a modified nucleobase, such as N6-methyladenine, N1-methyladenine, N6-2'-O-dimethyladenosine, pseudouridine, N1-methylpseudouridine, 5-iodouridine, 4-thiouridine, 2-thiouridine, 5-methyluridine, pseudoisocytosine, 5-methoxycytosine, 2-thiouridine, 5-hydroxycytosine, N1-methylcytosine, 5-hydroxymethylcytosine, hypoxanthine, N1-methylguanine, isoguanine, etc., preferably N1-methylguanine.

[0253] In another embodiment, B2 is a natural nucleobase, such as adenine (A), guanine (G), cytosine (C), uracil (U) and thymine (T), preferably adenine (A).

[0254] In another specific embodiment, B2 is selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally modified.

[0255] In another embodiment, B2 is adenine; in another embodiment, B2 is a modified adenine, such as an alkyl group (e.g., C 1-6 In another embodiment, B2 is adenine modified with an alkyl group, such as a methyl group, for example, N6-methyladenine; in another embodiment, B2 is guanine.

[0256] In another embodiment, B2 is a natural or modified adenine or guanine; preferably, B2 is a natural or modified adenine, such as a natural or alkyl (e.g., C 1-6 Adenine modified with an alkyl group, such as a methyl group, is preferably adenine.

[0257] In another specific embodiment, B3 is selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally modified.

[0258] In another embodiment, B3 is a natural nucleobase, such as adenine (A), guanine (G) or uracil (U), such as guanine (G) or uracil (U), preferably guanine (G).

[0259] In another embodiment, B3 is a natural nucleobase, such as guanine (G) or uracil (U), preferably guanine (G).

[0260] In another specific embodiment, B4 is selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally modified.

[0261] In another embodiment, B4 is a natural nucleobase, such as adenine (A), guanine (G) or uracil (U), such as guanine (G) or uracil (U), preferably guanine (G).

[0262] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i

[0263] In one embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i is H; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i is halogen; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 1-6 Alkyl, such as methyl, such as ethyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 1-6 Deuterated alkyl, preferably C 1-3 Deuterated alkyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、Rf 、R g 、R h or R i C 1-6 haloalkyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 2-6 alkenyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 2-6 Alkynyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 3-10 Cycloalkyl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i is a 3-10 membered heterocyclic group; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i C 6-10 aryl or 5-10 membered heteroaryl; in another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g、R h or R i C in 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl is optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 In another embodiment, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h or R i Not replaced.

[0264] In one embodiment, R a Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0265] In one embodiment, R b Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0266] In one embodiment, R c Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0267] In one embodiment, R dSelected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R d For H.

[0268] In one embodiment, R e Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R e It is a methyl group.

[0269] In one embodiment, R f Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0270] In one embodiment, R g Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0271] Any technical solution or any combination thereof in any of the above specific embodiments can be combined with any technical solution or any combination thereof in other specific embodiments. For example, any technical solution or any combination thereof of W can be combined with R X1 、RX2 , R1, R2, R3, R4, R5, R6, R7, X1, X2, X3, X4, Y1, Y2, Y3, Y4, R, R', B1, B2, B3, B4, R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i The present invention is intended to include all of these technical solutions, which are not listed one by one due to space limitations.

[0272] In another aspect, the present invention provides the following specific technical solutions:

[0273] Technical Solution 1. A compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0274] in,

[0275] R X1 OR a ;

[0276] R X2 OR b ;

[0277] W is selected from O or S;

[0278] R1 is selected from halogen or OR c ;

[0279] R2 is selected from halogen or OR d ;

[0280] R3 is selected from halogen or OR e ;

[0281] R4 is selected from halogen, OR f or

[0282] R5 is selected from halogen or OR g ;

[0283] R6 is selected from halogen or OR h ;

[0284] R7 is selected from halogen or OR i ;

[0285] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0286] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0287] 2) X1 is CH2CH2O,

[0288] 3) X2 is OCH2CH2;

[0289] 4) X3 is OCH2CH2;

[0290] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0291] R and R' are selected from H or halogen;

[0292] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0293] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0294] R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6haloalkoxy substitution;

[0295] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0296] Technical Solution 2. A compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0297] in,

[0298] X1, X2 and X3 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0299] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0300] 2) X1 is CH2CH2O,

[0301] 3) X2 is OCH2CH2;

[0302] R X1 OR a ;

[0303] R X2 OR b ;

[0304] W is selected from O or S;

[0305] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2;

[0306] R1 is selected from halogen or OR c ;

[0307] R2 is selected from halogen or OR d ;

[0308] R3 is selected from halogen or OR e ;

[0309] R4 is selected from halogen or OR f ;

[0310] R5 is selected from halogen or OR g ;

[0311] R and R' are selected from H or halogen;

[0312] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0313] B1, B2 and B3 are independently selected from natural, modified or unnatural nucleobases;

[0314] R a 、R b 、R c 、R d 、R e 、R f and R g independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0315] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0316] Technical Solution 3. The compound of formula (I) of Technical Solution 1 or 2, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, has the following general formula:

[0317] wherein each group is as defined herein.

[0318] Technical Solution 4. The general compound of any one of Technical Solutions 1-3, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X1 is selected from O, S or CH2, preferably CH2.

[0319] Technical Solution 5. The general compound of any one of Technical Solutions 1-4, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X2 is selected from O, S or CH2, preferably CH2.

[0320] Technical Solution 6. The general compound of any one of Technical Solutions 1-4, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X2 is OCH2.

[0321] Technical Solution 7. The general compound of any one of Technical Solutions 1-6, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X3 is selected from O, S or CH2, preferably CH2.

[0322] Technical Solution 8. The general compound of any one of Technical Solutions 1-6, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X3 is OCH2.

[0323] Technical Solution 9. The general compound of any one of Technical Solutions 1-8, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein X4 is OCH2.

[0324] Technical Solution 10. The compound of the general formula of any one of Technical Solutions 1-9, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R X1 OH, C 1-6 Alkoxy or C 1-6 The haloalkoxy group is preferably OH.

[0325] Technical Solution 11. The compound of the general formula of any one of Technical Solutions 1-10, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R X2 For OH.

[0326] Technical Solution 12. The general compound of any one of Technical Solutions 1-11, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein W is O.

[0327] Technical Solution 13. The compound of the general formula of any one of Technical Solutions 1-12, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein at least one of Y1, Y2 and Y3 is CH2; preferably, Y1 is CH2 and Y2 and Y3 are O; preferably, Y1 and Y2 are CH2, and Y3 is O;

[0328] Preferably, at least one of Y1, Y2, Y3 and Y4 is CH2.

[0329] Technical Solution 14. The compound of the general formula of any one of Technical Solutions 1-12, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein at least one of Y1, Y2 and Y3 is O, S or NH; preferably, one of Y1, Y2 and Y3 is O, S or NH; preferably, Y1, Y2 and Y3 are O;

[0330] Preferably, at least one of Y1, Y2, Y3 and Y4 is O, S or NH; preferably, Y3 is O; preferably, Y4 is O.

[0331] Technical Solution 15. The general compound of any one of Technical Solutions 1-14, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R1 is F or OH, preferably OH.

[0332] Technical Solution 16. The compound of the general formula of any one of Technical Solutions 1-15, or its stereoisomers, tautomers or isotopic variants, or its pharmaceutically acceptable salts, wherein R2 is F, OH, C 1-6 Alkoxy or C 1-6 Halogenated alkoxy, preferably OH, C 1-6 Alkoxy or C 1-6 Haloalkoxy; wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 Halogenated alkoxy substituted; preferably OH or C 1-6 Alkoxy (eg, OMe).

[0333] Technical Solution 17. The compound of the general formula of any one of Technical Solutions 1-16, or its stereoisomers, tautomers or isotopic variants, wherein R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, preferably OMe, or R' and R3 are linked to form CH2O or CH2CH2O;

[0334] Preferably, R3 is F, C 1-6 Alkoxy or C 1-6Haloalkoxy, wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0335] or R' and R3 are linked to form CH2O or CH2CH2O;

[0336] Preferably, R3 is F or C 1-6 Alkoxy, preferably C 1-6 Alkoxy (eg, OMe).

[0337] Technical Solution 18. The compound of the general formula of any one of Technical Solutions 1-17, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R4 and R5 are OH;

[0338] Preferably, R4 is

[0339] Technical Solution 19. The general compound of any one of Technical Solutions 1-18, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R6 and R7 are OH.

[0340] Technical Solution 20. The compound of the general formula of any one of Technical Solutions 1-19, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R and R' are H.

[0341] Technical Solution 21. The general compound of any one of Technical Solutions 1-20, or its stereoisomers, tautomers or isotopic variants, or its pharmaceutically acceptable salts, wherein B1 is natural or modified guanine, preferably alkyl-modified guanine, such as methyl-modified guanine.

[0342] Technical Solution 22. The compound of any one of Technical Solutions 1-21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably, B2 is adenine, and B3 is guanine or uracil, preferably guanine;

[0343] Preferably, B2, B3 and B4 are independently selected from adenine, guanine, cytosine, uracil and thymine, and the adenine, guanine, cytosine, uracil or thymine is optionally modified;

[0344] Preferably, B2 is a natural or modified adenine or guanine; preferably, B2 is a natural or modified adenine, preferably a natural or alkyl (e.g., C1-6 Alkyl, such as methyl) modified adenine, preferably adenine;

[0345] Preferably, B3 is adenine, guanine or uracil, preferably guanine or uracil, preferably guanine;

[0346] Preferably, B4 is adenine, guanine or uracil, preferably selected from guanine or uracil, preferably guanine.

[0347] Technical Solution 23. The compound of formula (I) according to any one of Technical Solutions 1 to 22, or a stereoisomer, tautomer or isotopic variant thereof, wherein the compound is selected from:

[0348] Technical Solution 24. The compound of formula (I) according to any one of Technical Solutions 1-23, or a stereoisomer, tautomer or isotopic variant thereof, wherein B2 is completely complementary to the nucleoside base at the transcription template position +1 on the nucleic acid template, and B3 is completely complementary to the nucleoside base at the transcription template position +2 on the nucleic acid template.

[0349] Technical solution 25. An RNA molecule comprising the compound of formula (I) according to any one of Technical Solutions 1 to 24, or a stereoisomer, tautomer or isotopic variant thereof at its 5′ end.

[0350] Technical solution 26. The RNA molecule of technical solution 25, which is an mRNA molecule.

[0351] Technical solution 27. A kit for capping RNA transcripts, comprising a compound of formula (I) according to any one of technical solutions 1 to 24, or a stereoisomer, tautomer or isotopic variant thereof.

[0352] Technical solution 28. The kit of technical solution 27 further comprises an RNA molecule, preferably an mRNA molecule.

[0353] Technical Solution 29. Use of the compound of formula (I) according to any one of Technical Solutions 1 to 24, or its stereoisomers, tautomers or isotopic variants as an in vitro co-transcribed RNA capping agent.

[0354] Technical solution 30. The use of technical solution 29, which is used for mRNA capping under an in vitro T7 RNA polymerase system.

[0355] Technical Solution 31. A method for synthesizing RNA, comprising incubating the compound of formula (I) according to any one of Technical Solutions 1-24, or its stereoisomers, tautomers or isotopic variants with a nucleotide template to perform template transcription.

[0356] Technical Solution 32. A complex comprising a compound of formula (I) according to any one of Technical Solutions 1 to 24, or a stereoisomer, tautomer or isotopic variant thereof, and a DNA template, wherein the DNA template includes a promoter region containing a transcription start site having a first nucleotide at nucleotide position +1 and a second nucleotide at nucleotide position +2; and B2 is complementary to the nucleoside base at transcription template position +1 on the DNA template, and B3 is complementary to the nucleoside base at transcription template position +2 on the DNA template.

[0357] In a more specific embodiment, the present invention provides a compound of formula (I'), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0358] in,

[0359] R X1 OR a ;

[0360] R X2 OR b ;

[0361] W is selected from O or S;

[0362] R1 is selected from halogen or OR c ;

[0363] R'1 is selected from H or halogen;

[0364] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0365] R'2 is selected from H or halogen;

[0366] R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ;

[0367] R4 is selected from halogen, OR f or

[0368] R5 is selected from halogen or OR g ;

[0369] R6 is selected from halogen or OR h ;

[0370] R7 is selected from halogen or OR i ;

[0371] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CHO, OCH2, CH2CH2O, OCH2CH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2; and at least one of the following conditions is met:

[0372] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0373] 2) X1 is CH2CH2O, OCH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2,

[0374] 3) X2 is OCH2CH2, CH2O, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2;

[0375] 4) X3 is OCH2CH2;

[0376] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0377] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0378] R' is selected from H or halogen;

[0379] or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0380] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0381] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0382] R a 、Rb 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0383] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, preferably deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, preferably deuterium.

[0384] In a more specific embodiment, the present invention provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0385] in,

[0386] R X1 OR a ;

[0387] R X2 OR b ;

[0388] W is selected from O or S;

[0389] R1 is selected from halogen or OR c ;

[0390] R2 is selected from halogen or OR d ;

[0391] R3 is selected from halogen or OR e ;

[0392] R4 is selected from halogen, OR f or

[0393] R5 is selected from halogen or OR g ;

[0394] R6 is selected from halogen or OR h ;

[0395] R7 is selected from halogen or OR i ;

[0396] X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0397] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0398] 2) X1 is CH2CH2O,

[0399] 3) X2 is OCH2CH2;

[0400] 4) X3 is OCH2CH2;

[0401] Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2;

[0402] R and R' are selected from H or halogen;

[0403] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0404] B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases;

[0405] R a 、R b 、R c 、R d 、Re 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0406] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0407] In a more specific embodiment, the present invention provides a compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof:

[0408] in,

[0409] X1, X2 and X3 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met:

[0410] 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2,

[0411] 2) X1 is CH2CH2O,

[0412] 3) X2 is OCH2CH2;

[0413] R X1 OR a ;

[0414] R X2 OR b ;

[0415] W is selected from O or S;

[0416] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2;

[0417] R1 is selected from halogen or OR c ;

[0418] R2 is selected from halogen or OR d ;

[0419] R3 is selected from halogen or OR e ;

[0420] R4 is selected from halogen or OR f ;

[0421] R5 is selected from halogen or OR g ;

[0422] R and R' are selected from H or halogen;

[0423] or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2;

[0424] B1, B2 and B3 are independently selected from natural, modified or unnatural nucleobases;

[0425] R a 、R b 、R c 、R d 、R e 、R f and R g independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0426] wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

[0427] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X1 is selected from O, S or CH2, preferably CH2;

[0428] Preferably, X1 is selected from O, CH2, CH2CH2, CH═CH, CHO, OCH2, CH2CH2O, C(═CH2)CH2, CH2C(═CH2), C(O)CH2 or C(S)CH2, preferably O, CH2, CH2CH2, CH═CH, CHO, OCH2 or CH2CH2O, preferably CH2, CH2CH2, CHO, OCH2 or CH2CH2O.

[0429] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X2 is selected from O, S or CH2, preferably CH2;

[0430] Preferably, X2 is selected from CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2, preferably CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2.

[0431] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X3 is selected from O, S or CH2, preferably CH2;

[0432] Preferably, X3 is selected from CH2, CH2CH2, OCH2 or OCH2CH2, preferably OCH2.

[0433] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X4 is OCH2.

[0434] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R X1 OH, C 1-6 Alkoxy or C 1-6 Haloalkoxy, preferably OH;

[0435] Preferably, R X1 OR a ;

[0436] R a Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

[0437] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R X2 For OH.

[0438] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein W is O.

[0439] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein at least one of Y1, Y2 and Y3 is CH2; preferably, Y1 is CH2 and Y2 and Y3 are O; preferably, Y2 is CH2 and Y1 and Y3 are O; preferably, Y3 is CH2 and Y1 and Y2 are O; preferably, Y1 and Y2 are CH2 and Y3 is O;

[0440] Preferably, at least one of Y1, Y2, Y3 and Y4 is CH2.

[0441] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein at least one of Y1, Y2 and Y3 is O, S or NH; preferably, one of Y1, Y2 and Y3 is O, S or NH;

[0442] Preferably, at least one of Y1, Y2, Y3 and Y4 is O, S or NH;

[0443] Preferably, Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y2 and Y3 are O; preferably Y1 and Y3 are O;

[0444] Preferably, Y3 is O; preferably, Y4 is O.

[0445] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R1 is F or OH, preferably OH;

[0446] Preferably, R1 is selected from halogen or OR c , preferably OR c ;

[0447] Preferably, R c Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H;

[0448] Preferably, R and R1 are optionally linked to form OCH2 or OCH2CH2, preferably OCH2;

[0449] Preferably, R'1 is selected from H or F, preferably H.

[0450] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R2 is F, OH, C 1-6 Alkoxy or C 1-6 Halogenated alkoxy, preferably OH, C 1-6 Alkoxy or C 1-6 Haloalkoxy; wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 Halogenated alkoxy substituted; preferably OH or C 1-6 Alkoxy (e.g., OMe);

[0451] Preferably, R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , preferably F, C1-3 Alkyl, C 1-3 Haloalkyl or OR d wherein the alkyl and haloalkyl are optionally substituted by 1 group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Halogenated alkyl, preferably NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl (preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 haloalkyl), preferably C 1-6 Alkoxy or C 1-6 Halogenated alkoxy (preferably C 1-3 Alkoxy or C 1-3 haloalkoxy);

[0452] Preferably, R2 is selected from halogen or OR d , preferably OR d ;

[0453] Preferably, R d Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R d is H;

[0454] Preferably, R'2 is selected from H or F, preferably H.

[0455] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, or R' and R3 are optionally linked to form CH2O or CH2CH2O, preferably CH2O;

[0456] Preferably, R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0457] or R' and R3 are optionally linked to form CH2O or CH2CH2O, preferably CH2O;

[0458] Preferably, R3 is F or C 1-6 Alkoxy, preferably C 1-6 Alkoxy (e.g., OMe);

[0459] Preferably, R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ;

[0460] R e Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R e It is a methyl group.

[0461] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R4 and R5 are OH;

[0462] Preferably, R4 is

[0463] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R6 and R7 are OH.

[0464] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R and R' are H.

[0465] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, wherein B1 is natural or modified guanine, preferably alkyl-modified guanine, such as methyl-modified guanine.

[0466] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably, B2 is adenine, and B3 is guanine or uracil, preferably guanine;

[0467] Preferably, B2, B3 and B4 are independently selected from adenine, guanine, cytosine, uracil and thymine, and the adenine, guanine, cytosine, uracil or thymine is optionally modified;

[0468] Preferably, B2 is a natural or modified adenine or guanine; preferably, B2 is a natural or modified adenine, preferably a natural or alkyl (e.g., C 1-6 Alkyl, such as methyl) modified adenine, preferably adenine;

[0469] Preferably, B3 is adenine, guanine or uracil, preferably guanine or uracil, preferably guanine;

[0470] Preferably, B4 is adenine, guanine or uracil, preferably selected from guanine or uracil, preferably guanine.

[0471] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the following general formula:

[0472] wherein each group is as defined in the present invention.

[0473] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (II-a):

[0474] in,

[0475] R X1 OR a ;

[0476] R X2 OR b ;

[0477] W is selected from O or S;

[0478] R1 is selected from halogen or OR c ;

[0479] R2 is selected from halogen or OR d ;

[0480] R3 is selected from halogen or OR e ;

[0481] R4 is selected from halogen or OR f ;

[0482] R5 is selected from halogen or OR g ;

[0483] X2 is selected from CH2 or OCH2, preferably OCH2;

[0484] X3 is OCH2;

[0485] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0486] R' is selected from H or halogen;

[0487] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O;

[0488] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil;

[0489] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide;

[0490] R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0491] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0492] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0493] R X1 OR a , such as OH or OCH3, preferably OH;

[0494] R X2 OR b , such as OH;

[0495] W is selected from O or S, preferably O;

[0496] R1 is selected from F or OR c , such as F or OH; preferably OR c , such as OH;

[0497] R2 is OR d , such as OH, OCH3 or OCH2CH2OCH3, preferably OH or OCH3, preferably OH;

[0498] R3 is selected from F or OR e , such as F, OCH3 or OCH2CH3; preferably OR e , such as OCH3 or OCH2CH3, preferably OCH3;

[0499] R4 is OR f , such as OH;

[0500] R5 is OR g , such as OH;

[0501] X2 is selected from CH2 or OCH2, preferably OCH2;

[0502] X3 is OCH2;

[0503] Y1, Y2 and Y3 are O;

[0504] R' is H;

[0505] or R' and R3 are optionally linked to form CH2O;

[0506] B2 is adenine;

[0507] B3 is guanine or uracil, preferably guanine;

[0508] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H;

[0509] R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution;

[0510] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0511] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (III-a):

[0512] in,

[0513] R X1 OR a ;

[0514] R X2 OR b ;

[0515] W is selected from O or S;

[0516] R1 is selected from halogen or OR c ;

[0517] R2 is selected from halogen or OR d ;

[0518] R3 is selected from halogen or OR e ;

[0519] R4 is selected from halogen or OR f ;

[0520] R5 is selected from halogen or ORg ;

[0521] X1 is selected from CH2O or CH=CH, preferably CH2O;

[0522] X3 is OCH2;

[0523] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0524] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0525] R' is selected from H or halogen;

[0526] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O;

[0527] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil;

[0528] R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide;

[0529] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0530] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0531] R X1 OR a , such as OH;

[0532] R X2 OR b , such as OH;

[0533] W is O;

[0534] R1 is OR c , such as OH;

[0535] R2 is OR d, such as OH or OCH3, preferably OH;

[0536] R3 is OR e , such as OCH3;

[0537] R4 is OR f , such as OH;

[0538] R5 is OR g , such as OH;

[0539] X1 is selected from CH2O or CH=CH, preferably CH2O;

[0540] X3 is OCH2;

[0541] Y1, Y2 and Y3 are O;

[0542] R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H;

[0543] R' is H;

[0544] B2 is adenine;

[0545] B3 is guanine or uracil, preferably guanine;

[0546] R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H;

[0547] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0548] In a more specific embodiment, the present invention provides the above-mentioned compound, or its stereoisomer, tautomer or isotopic variant, or its pharmaceutically acceptable salt, which has the structure of formula (II-c-2):

[0549] in,

[0550] R X1 OR a ;

[0551] R X2 OR b ;

[0552] W is selected from O or S;

[0553] R1 is selected from halogen or OR c ;

[0554] R'1 is selected from H or halogen;

[0555] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0556] R'2 is selected from H or halogen;

[0557] R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ;

[0558] R4 is selected from halogen or OR f ;

[0559] R5 is selected from halogen or OR g ;

[0560] X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2;

[0561] X3 is OCH2;

[0562] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y2 and Y3 are O;

[0563] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0564] R' is selected from H or halogen;

[0565] or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably OCH2 or OCH2CH2;

[0566] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O;

[0567] RB1 Selected from C 1-3 Alkyl or C 1-3 deuterated alkyl;

[0568] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally replaced by 1 C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Preferably B2 is natural or modified by 1 C 1-6 Alkyl-modified adenine, B3 is guanine or uracil;

[0569] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide;

[0570] R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0571] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0572] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0573] R X1 OR a ;

[0574] R X2 OR b ;

[0575] W is selected from O or S, preferably O;

[0576] R1 is selected from F or OR c , preferably OR c ;

[0577] R'1 is selected from H or F, preferably H;

[0578] R2 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 alkyl halide;

[0579] R'2 is selected from H or F, preferably H;

[0580] R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ;

[0581] R4 is OR f ;

[0582] R5 is OR g ;

[0583] X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2;

[0584] X3 is OCH2;

[0585] Y1 is selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0586] Y2 and Y3 are O;

[0587] R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H;

[0588] R' is H;

[0589] or R and R1 are optionally linked to form OCH2;

[0590] or R' and R3 are optionally linked to form CH2O;

[0591] R B1 Selected from C 1-3 Alkyl or C 1-3Deuterated alkyl, preferably C 1-3 alkyl;

[0592] B2 is natural or covered by 1 C 1-3 Alkyl (e.g., methyl)-modified adenine;

[0593] B3 is guanine or uracil, preferably guanine;

[0594] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H;

[0595] R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution;

[0596] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0597] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0598] R X1 for OH;

[0599] R X2 for OH;

[0600] W is selected from O or S, preferably O;

[0601] R1 is selected from F or OH, preferably OH;

[0602] R'1 is selected from H or F, preferably H;

[0603] R2 is selected from F, CH2F, CF2H, CHOCH3, CH2NHC(O)CH3, OH, OCH3, OCD3 or OCH2CH2OCH3, preferably CF2H, CHOCH3, CH2NHC(O)CH3, OH, OCH3 or OCD3;

[0604] R'2 is selected from H or F, preferably H;

[0605] R3 is selected from F, CF2H, OCH3, OCH2CH3, OCH2CH2OCH3, OCD3 or OCF3, preferably F, OCH3 or OCH2CH3, preferably OCH3 or OCH2CH3, preferably F or OCH3, preferably OCH3;

[0606] R4 is OH;

[0607] R5 is OH or OCH3, preferably OH;

[0608] X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2;

[0609] X3 is OCH2;

[0610] Y1 is selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0611] Y2 and Y3 are O;

[0612] R is selected from H or CHFCH3, preferably H;

[0613] R' is H;

[0614] or R and R1 are optionally linked to form OCH2;

[0615] or R' and R3 are optionally linked to form CH2O;

[0616] R B1 Selected from CH3 or CD3, preferably CH3;

[0617] B2 is adenine or N6-methyladenine, preferably adenine;

[0618] B3 is guanine or uracil, preferably guanine.

[0619] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (III-c):

[0620] in,

[0621] R X1 OR a ;

[0622] R X2 OR b ;

[0623] W is O or S, preferably O;

[0624] R1 is selected from halogen or OR c ;

[0625] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0626] R3 is selected from halogen or OR e , preferably OR e ;

[0627] R4 is selected from halogen or OR f ;

[0628] R5 is selected from halogen or OR g ;

[0629] X1 is selected from CH2O, CH=CH or CH2CH2, preferably CH2O or CH2CH2, preferably CH2O;

[0630] X3 is OCH2;

[0631] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y1 and Y3 are O;

[0632] R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide;

[0633] R' is selected from H or halogen;

[0634] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil;

[0635] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide;

[0636] R d and R e Independently selected from H, C1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0637] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0638] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0639] R X1 OR a , such as OH;

[0640] R X2 OR b , such as OH;

[0641] W is O;

[0642] R1 is OR c , such as OH;

[0643] R2 is selected from C 1-3 Alkyl, C 1-3 Haloalkyl or OR d (preferably OH), wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Haloalkyl; for example CF2H, CH2NHC(O)CH3, OH or OCH3, preferably CF2H, CH2NHC(O)CH3 or OH;

[0644] R3 is selected from F or OR e , such as F, OCH3, OCH2CH3 or OCH2CH2OCH3, preferably F or OCH3, preferably OCH3;

[0645] R4 is OR f , such as OH;

[0646] R5 is OR g , such as OH;

[0647] X1 is selected from CH2O, CH=CH or CH2CH2, preferably CH2O or CH2CH2, preferably CH2O;

[0648] X3 is OCH2;

[0649] Y1 and Y3 are O;

[0650] Y2 is selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0651] R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H;

[0652] R' is H;

[0653] B2 is adenine;

[0654] B3 is guanine or uracil, preferably guanine;

[0655] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H;

[0656] R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution;

[0657] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0658] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (Va):

[0659] in,

[0660] R X1 OR a , such as OH;

[0661] R X2 OR b , such as OH;

[0662] W is O or S, preferably O;

[0663] R1 is selected from halogen or OR c , preferably OR c , such as OH;

[0664] R2 is selected from halogen or OR d , preferably OR c , such as OH or OCH3, preferably OH;

[0665] R3 is selected from halogen (preferably F) or OR e , such as F, OCH3 or OCH2CH3, preferably OCH3;

[0666] R4 is selected from halogen or OR f , preferably OR f , such as OH;

[0667] R5 is selected from halogen or OR g , preferably OR g , such as OH;

[0668] X2 and X3 are OCH2;

[0669] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0670] R' is selected from H or halogen, preferably H;

[0671] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine;

[0672] R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H;

[0673] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0674] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (Vb):

[0675] in,

[0676] R X1 OR a , such as OH;

[0677] R X2 OR b , such as OH;

[0678] W is O or S, preferably O;

[0679] R1 is halogen (preferably F) or OR c , such as F or OH; preferably OR c , such as OH;

[0680] R2 is selected from halogen or OR d , preferably OR c , such as OH or OCH3, preferably OH;

[0681] R3 is selected from halogen (preferably F) or OR e , preferably OR e , such as OCH3;

[0682] R4 is selected from halogen or OR f , preferably OR f , such as OH;

[0683] R5 is selected from halogen or OR g , preferably OR g , such as OH;

[0684] X1 is selected from CH2O or CH=CH, preferably CH2O;

[0685] X3 is OCH2;

[0686] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0687] R is selected from H, C 1-6 Alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H;

[0688] R' is selected from H or halogen, preferably H;

[0689] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine;

[0690] R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H;

[0691] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0692] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (II-d):

[0693] in,

[0694] R X1 OR a ;

[0695] R X2 OR b ;

[0696] W is selected from O or S;

[0697] R1 is selected from halogen or OR c ;

[0698] R'1 is selected from H or halogen;

[0699] R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide;

[0700] R'2 is selected from H or halogen;

[0701] R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ;

[0702] R4 is selected from halogen or OR f ;

[0703] R5 is selected from halogen or OR g ;

[0704] X2 is selected from OCH2 or CH=CH, preferably OCH2;

[0705] X3 is OCH2;

[0706] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0707] R and R' are independently selected from H or halogen;

[0708] or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O;

[0709] R B1 Selected from C 1-3 Alkyl or C 1-3 deuterated alkyl;

[0710] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally replaced by 1 C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Preferably B2 is natural or modified by 1 C 1-6 Alkyl-modified adenine, B3 is guanine or uracil;

[0711] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide;

[0712] Rd and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution;

[0713] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0714] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0715] R X1 OR a ;

[0716] R X2 OR b ;

[0717] W is selected from O or S, preferably O;

[0718] R1 is selected from F or OR c , preferably OR c ;

[0719] R'1 is selected from H or F, preferably H;

[0720] R2 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Halogenated alkyl, preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 alkyl halide;

[0721] R'2 is selected from H or F, preferably H;

[0722] R3 is selected from F, C 1-3 Alkyl, C1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ;

[0723] R4 is OR f ;

[0724] R5 is OR g ;

[0725] X2 is selected from OCH2 or CH=CH, preferably OCH2;

[0726] X3 is OCH2;

[0727] Y1, Y2 and Y3 are independently selected from O or CH2, preferably O;

[0728] R and R' are H;

[0729] or R' and R3 are optionally linked to form CH2O;

[0730] R B1 Selected from C 1-3 Alkyl or C 1-3 Deuterated alkyl, preferably C 1-3 alkyl;

[0731] B2 is natural or covered by 1 C 1-3 Alkyl (e.g., methyl)-modified adenine;

[0732] B3 is guanine or uracil, preferably guanine;

[0733] R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 alkyl halide;

[0734] R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution;

[0735] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0736] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein,

[0737] R X1 for OH;

[0738] R X2 for OH;

[0739] W is O;

[0740] R1 is selected from F or OH, preferably OH;

[0741] R'1 is selected from H or F, preferably H;

[0742] R2 is selected from F, CH2F, CF2H, CH2OCH3, CH2NHC(O)CH3, OH or OCH3, preferably CF2H, CH2NHC(O)CH3, OH or OCH3;

[0743] R'2 is selected from H or F, preferably H;

[0744] R3 is selected from F, CF2H, OCH3, OCH2CH3 or OCF3, preferably F or OCH3, preferably OCH3;

[0745] R4 is OH;

[0746] R5 is OH;

[0747] X2 is selected from OCH2 or CH=CH, preferably OCH2;

[0748] X3 is OCH2;

[0749] Y1, Y2 and Y3 are O;

[0750] R and R' are H;

[0751] or R' and R3 are optionally linked to form CH2O;

[0752] R B1 Selected from CH3 or CD3, preferably CH3;

[0753] B2 is adenine or N6-methyladenine, preferably adenine;

[0754] B3 is guanine or uracil, preferably guanine.

[0755] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has a structure of formula (III-d):

[0756] in,

[0757] R X1 OR a , such as OH;

[0758] R X2 OR b , such as OH;

[0759] W is O or S, preferably O;

[0760] R1 is selected from halogen or OR c , preferably OR c , such as OH;

[0761] R2 is selected from C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d wherein the alkyl and haloalkyl are optionally substituted by one group selected from the group consisting of: NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Haloalkyl, such as CF2H, CH2NHC(O)CH3, OH or OCH3; preferably OR d , such as OH or OCH3, preferably OCH3;

[0762] R3 is selected from halogen or OR e , preferably OR e , such as OCH3;

[0763] R4 is selected from halogen or OR f , preferably OR f , such as OH;

[0764] R5 is selected from halogen or OR g , preferably OR g , such as OH;

[0765] X1 is selected from CH2O;

[0766] X3 is OCH2;

[0767] Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O;

[0768] R is selected from H, C 1-6 Alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H;

[0769] R' is selected from H or halogen, preferably H;

[0770] B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine;

[0771] R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H;

[0772] Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

[0773] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein the compound is selected from:

[0774] In a more specific embodiment, the present invention provides the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein B2 is completely complementary to the nucleoside base at the transcription template position +1 on the nucleic acid template, and B3 is completely complementary to the nucleoside base at the transcription template position +2 on the nucleic acid template.

[0775] In a more specific embodiment, the present invention also provides an RNA molecule comprising a compound of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, at the 5' end.

[0776] In a more specific embodiment, the present invention provides the above-mentioned RNA molecule, which is an mRNA molecule.

[0777] In a more specific embodiment, the present invention provides a kit for capping RNA transcripts comprising a compound of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof.

[0778] In a more specific embodiment, the present invention provides the above kit, further comprising an RNA molecule, preferably an mRNA molecule.

[0779] In a more specific embodiment, the present invention provides use of the above-mentioned compound, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof as an in vitro co-transcribed RNA capping agent.

[0780] In a more specific embodiment, the present invention provides the above use for mRNA capping under an in vitro T7 RNA polymerase system.

[0781] In a more specific embodiment, the present invention provides a method for synthesizing RNA, comprising incubating a compound of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof with a nucleotide template to perform template transcription.

[0782] In a more specific embodiment, the present invention provides a complex comprising a compound of the present invention, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, and a DNA template, wherein the DNA template includes a promoter region comprising a transcription start site having a first nucleotide at nucleotide position +1 and a second nucleotide at nucleotide position +2; and B2 is complementary to the nucleobase at transcription template position +1 on the DNA template, and B3 is complementary to the nucleobase at transcription template position +2 on the DNA template.

[0783] Example

[0784] The following specific embodiments illustrate the present invention. Those skilled in the art will readily appreciate the advantages and effects of the present invention based on the disclosure herein. Without intending to be bound by any theory, the following examples are intended solely to illustrate the compounds, preparation methods, and uses of the present invention and are not intended to limit the scope of the present invention.

[0785] Example 1: Synthesis of Intermediate B

[0786] 2'OMe-rA phosphoramidite monomer (240.0 g, 270.3 mmol) and N2-isobutyryl-2',3'acetylguanosine (118.3 g, 270.3 mmol) were weighed and dissolved in DCM (2.4 L). Tetrazole (28.4 g, 405.4 mmol) was added under a nitrogen atmosphere. Stir at room temperature for 2 hours. After the reaction, tert-butyl hydroperoxide (104.4 g, 810.9 mmol, 70%) was added dropwise to the reaction mixture and the reaction continued at room temperature for 1 hour. After the reaction, the reaction mixture was washed with 10% sodium sulfite solution until the starch potassium iodide test paper did not change color. The organic phase was concentrated to obtain crude intermediate B1 (301.7 g, 90.0%), which was directly carried out to the next step without purification.

[0787] Intermediate B1 (301.7 g, 243.3 mmol) was weighed and dissolved in DCM (2.0 L). A solution of trichloroacetic acid (119.3 g, 729.9 mmol) in DCM (1.0 L) was added dropwise to the reaction mixture at room temperature. The reaction was allowed to react for 2 hours. The reaction mixture was washed with 10% aqueous sodium bicarbonate solution and saturated brine, respectively. The organic phase was concentrated under reduced pressure and purified by column chromatography to yield Intermediate B2 (174.1 g, 76.3%).

[0788] Intermediate B2 (174.1 g, 185.6 mmol) and bis(2-cyanoethyl)-N,N-diisopropylphosphoramidite (75.5 g, 278.4 mmol) were dissolved in DCM (1.7 L). Tetrazole (19.6 g, 278.4 mmol) was added under a nitrogen atmosphere. The mixture was stirred at room temperature for 2 hours. After the reaction, tert-butyl hydroperoxide (71.7 g, 556.8 mmol, 70%) was added dropwise to the reaction mixture, and the reaction was continued at room temperature for 1 hour. After the reaction, the reaction mixture was washed with 10% sodium sulfite solution until it did not change color on starch potassium iodide paper. The organic phase was concentrated under reduced pressure and purified by column chromatography to obtain Intermediate B3 (179.4 g, 86.0%).

[0789] Intermediate B3 (159.6 mmol) was weighed and dissolved in methanol (0.5 L) and aqueous ammonia (1.3 L), and stirred at room temperature overnight. After completion of the reaction, the mixture was concentrated under reduced pressure and stripped twice with water (200.0 ml) to remove the solvent. The mixture was then diluted with water and loaded onto a DEAE Sephadex plate. Elution was performed using a gradient of 0-1.0 M aqueous TEAB. The pure fractions were collected, concentrated, and lyophilized to yield the triethylamine salt of Intermediate B (119.8 g, 74.3%). The reaction scheme is shown below:

[0790] Example 2: Synthesis of Intermediate D

[0791] Guanosine sodium diphosphate (17.1 g, 35.1 mmol) was weighed and dissolved in purified water (171.0 mL). The reaction solution was cooled to 4°C and dimethyl sulfate (35.4 g, 280.8 mmol) was slowly added dropwise. During the process, the pH was adjusted between 4 and 5 with 2 M sodium hydroxide. The reaction was monitored by HPLC. After the reaction was completed, the solution was diluted with water and loaded onto DEAE Sephadex. Gradient elution was performed with a 0-1.0 M TEAB aqueous solution. The pure fractions were collected, concentrated under reduced pressure, and lyophilized to obtain the triethylamine salt of intermediate D1 (17.7 g, 76.4%).

[0792] Intermediate D1 (17.7 g, 26.8 mmol) was weighed and suspended in DMF (177.0 mL). Triphenylphosphine (14.1 g, 53.6 mmol), 2,2'-disulfidedipyridine (11.8 g, 53.6 mmol), imidazole (14.7 g, 215.2 mmol), and triethylamine (2.7 g, 26.8 mmol) were added sequentially at room temperature. The mixture was stirred at room temperature under a nitrogen atmosphere for 10 hours. After completion of the reaction, the reaction mixture was slowly added to a solution of sodium perchlorate (107.4 mmol) in acetone (1.6 L). The precipitated solid was filtered and the filter cake was thoroughly washed with acetone until it turned white. The solvent was removed under reduced pressure to obtain the sodium salt of Intermediate D (12.4 g, 83.3%).

[0793] Example 3: Synthesis of Intermediate F

[0794] 3'-Methoxyguanosine (23.8 g, 80.0 mmol) and tributylamine (14.8 g, 80.0 mmol) were weighed and dissolved in trimethyl phosphate (238.0 mL). After cooling the mixture to -5°C, phosphorus oxychloride (24.5 g, 160.0 mmol) was added dropwise. The temperature was maintained for 3 hours. After completion of the reaction, the reaction was quenched with 1 M TEAB at 0°C. After dilution, the column was loaded onto a DEAE Sephadex column and eluted with a gradient of 0-1.0 M TEAB aqueous solution. The pure solution was concentrated under reduced pressure and lyophilized to yield the triethylamine salt of intermediate F1 (32.1 g, 83.9%).

[0795] The triethylamine salt of Intermediate F1 (32.1 g, 67.1 mmol) was weighed and suspended in DMF (321.0 mL). Triphenylphosphine (35.2 g, 134.2 mmol), 2,2'-disulfidedipyridine (29.6 g, 134.2 mmol), imidazole (36.6 g, 550.0 mmol), and triethylamine (6.8 g, 67.1 mmol) were added sequentially at room temperature. The mixture was stirred overnight at room temperature under a nitrogen atmosphere. After completion of the reaction, the reaction mixture was slowly added to a solution of sodium perchlorate (268.4 mmol) in acetone (2.6 L). The precipitated solid was filtered and the filter cake was thoroughly washed with acetone until it turned white. The solvent was removed under reduced pressure to obtain the sodium salt of Intermediate F2 (25.0 g, 83%).

[0796] Intermediate F2 (25.0 g, 55.7 mmol) and tributylamine phosphate (47.3 g, 167.1 mmol) were weighed and suspended in DMF (250.0 mL). Under a nitrogen atmosphere, the mixture was cooled to 0°C, and zinc chloride (60.8 g, 445.6 mmol) was added portionwise to the mixture. Stirring was then performed at room temperature for 5 hours. After completion of the reaction, the mixture was diluted with water, loaded onto a DEAE Sephadex, and eluted with a gradient of 0-1.0 M aqueous TEAB. The pure fractions were collected, concentrated under reduced pressure, and lyophilized to yield the triethylamine salt of Intermediate F3 (23.1 g, 63%).

[0797] Intermediate F4-F was obtained by referring to the synthesis method of intermediate D1-D in Example 2.

[0798] The reaction process is as follows:

[0799] Example 4: Synthesis of the ammonium salt of compound 15 using intermediate B and intermediate G as raw materials

[0800] Intermediate B (15.0 mmol) and intermediate G (10.0 mmol) were suspended in DMSO (105.0 mL), and ZnCl2 (85.0 mmol) was added to the reaction solution under ice bath. After stirring at room temperature for 36 hours, the reaction was terminated with 0.25 M EDTA-2Na (135.0 mmol). The mixture was loaded onto a DEAE Sephadex column. The product was eluted using a 0-1.0 M aqueous ammonium bicarbonate gradient. Fractions with a purity greater than 98% were collected, desalted by nanofiltration, and concentrated to obtain the ammonium salt of compound 15. The reaction scheme is shown below:

[0801] Among them, intermediate G is obtained by the following steps:

[0802] Intermediate A1 (12.0 g, 42.7 mmol) was dissolved in pyridine (120 mL). 4,4′-bis(methoxytrityl) chloride (DMTrCl, 15.9 g, 47 mmol) was added portionwise under an ice bath and stirred at room temperature overnight. After completion of the reaction, the solvent was concentrated under reduced pressure and purified by column chromatography to yield Intermediate G1 (22.5 g, 90.2%).

[0803] Intermediate G1 (22.5 g, 38.5 mmol) was weighed and dissolved in pyridine (225 mL). 4-Dimethylaminopyridine (0.5 g, 3.9 mmol) and isobutyryl chloride (16.4 g, 154 mmol) were added to the reaction mixture under ice-cooling. The temperature was raised to 80°C and stirred overnight. After the reaction, the pyridine was removed by concentration under reduced pressure. The resulting paste was dissolved in ethyl acetate (300 mL), washed with water (300 mL), and the organic phase was concentrated under reduced pressure. The crude product was purified by column chromatography to yield Intermediate G2 (28.3 g, 92.5%).

[0804] Intermediate G2 (28.3 g, 35.6 mmol) was weighed and dissolved in dichloromethane (283 mL). A solution of trichloroacetic acid (17.5 g, 106.8 mmol) in dichloromethane (100 mL) was added dropwise to the reaction mixture. Stir at room temperature for 2 hours. After completion of the reaction, the reaction mixture was washed with 10% aqueous sodium bicarbonate solution (300 mL). The organic phase was concentrated under reduced pressure and purified by column chromatography to yield Intermediate G3 (16.4 g, 93.8%).

[0805] Intermediate G3 (16.4 g, 33.4 mmol) was weighed and dissolved in DMF (164.0 mL). DMSO (15.7 g, 200.4 mmol) and EDCI (15.6 g, 100.2 mmol) were added to the reaction mixture at room temperature, followed by the dropwise addition of pyridine (2.6 g, 33.4 mmol) and trifluoroacetic acid (3.8 g, 33.4 mmol). After 5 hours of reaction at room temperature, the reaction mixture was poured into water (1.2 L) and extracted twice with ethyl acetate (200.0 mL). The combined organic phases were washed with saturated aqueous sodium bicarbonate (300.0 mL) and saturated aqueous sodium chloride (300.0 mL), respectively, and concentrated under reduced pressure. The crude product was purified by column chromatography to yield Intermediate G4 (12.7 g, 77.6%).

[0806] Tetraethylmethylene diphosphate (11.2 g, 38.8 mmol) was added dropwise to a suspension of NaH (1.6 g, 60%, 38.8 mmol) in THF (100 mL) under ice-cooling, followed by stirring at 0°C for 0.5 hours. A solution of Intermediate G4 (12.7 g, 25.9 mmol) in THF (127.0 mL) was slowly added dropwise to the reaction mixture. The mixture was stirred at room temperature overnight. After completion of the reaction, saturated aqueous ammonium chloride (300.0 mL) was added dropwise to the reaction mixture under ice-cooling to quench the reaction. The mixture was extracted twice with ethyl acetate (250.0 mL). The organic phases were combined, concentrated under reduced pressure, and purified by column chromatography to yield Intermediate G5 (13.3 g, 82.3%).

[0807] Intermediate G5 (13.3 g, 21.3 mmol) was dissolved in methanol (133 mL). The reaction system was purged with nitrogen, and palladium on carbon (0.1 eq.) was added. The mixture was then reacted at room temperature for 1 hour under a hydrogen atmosphere (1 atmosphere). After the reaction, the hydrogen in the reaction system was purged with nitrogen, and the palladium on carbon was removed by filtration. The filtrate was concentrated under reduced pressure to yield intermediate G6 (12.7 g, 95.3%).

[0808] Intermediate G6 (12.7 g, 20.3 mmol) was weighed and dissolved in dichloromethane (127.0 mL). Trimethylsilyl bromide (31.1 g, 203 mmol) was added to the reaction mixture at room temperature. Stir overnight at room temperature. After completion of the reaction, the mixture was concentrated under reduced pressure to obtain the crude intermediate G7, which was carried on to the next step without purification.

[0809] The crude intermediate G7 from the previous step was dissolved in concentrated aqueous ammonia (150.0 mL) and methanol (50.0 mL), heated to 60°C, and stirred for 8 hours. After completion of the reaction, the mixture was concentrated under reduced pressure and stripped twice with water (100.0 mL) to remove the solvent. The mixture was then diluted with water and loaded onto a DEAE Sephadex column. The elution was performed using a linear gradient of 0-1.0 M aqueous TEAB. The pure fractions were collected, concentrated, and lyophilized to afford the triethylamine salt of intermediate G8 (8.6 g, 75.8% yield over two steps).

[0810] Intermediate G9-G was obtained by the synthesis method of intermediate F2-F in Reference Example 3. The reaction scheme is as follows:

[0811] Example 5: Synthesis of the ammonium salt of compound 22 using intermediate D and intermediate H as raw materials

[0812] Using intermediates D and H as raw materials, the ammonium salt of compound 22 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0813] Among them, intermediate H is obtained by the following steps:

[0814] Intermediates H2-H4 were obtained by referring to the synthesis method of intermediates G4-G6 in Example 4.

[0815] Intermediate H4 (8.3 g, 13.1 mmol) was weighed and dissolved in tetrahydrofuran (83 mL). Tetrabutylammonium fluoride (5.1 g, 19.7 mmol) was added to the reaction mixture at room temperature. The reaction was stirred at room temperature for 2 hours, and the reaction was complete. The reaction mixture was concentrated under reduced pressure, ethyl acetate (200 mL) was added, and the mixture was washed with 1M HCl (200 mL). The organic phase was concentrated under reduced pressure and purified by column chromatography to yield Intermediate H5 (6.1 g, 90%).

[0816] Intermediate H5 (6.1 g, 11.8 mmol) was weighed and dissolved in dichloromethane. Bis(diisopropylamino)(2-cyanoethoxy)phosphine (3.9 g, 13.0 mmol) and tetrazole (0.9 g, 13.0 mmol) were added to the reaction mixture under a nitrogen atmosphere. The mixture was stirred at room temperature for 2 hours. After completion of the reaction, the solvent was concentrated under reduced pressure. The crude product was purified by column chromatography to yield Intermediate H6 (7.4 g, 87.6%).

[0817] Intermediate H7 was obtained by referring to the synthesis method of intermediate B1 in Example 1.

[0818] Intermediate H7 (5.5 g, 5.1 mmol) was weighed and dissolved in dichloromethane (127.0 mL). Trimethylsilyl bromide (7.8 g, 51 mmol) was added to the reaction mixture at room temperature. Stir overnight at room temperature. After completion of the reaction, the crude product of Intermediate H8 was concentrated under reduced pressure and carried on to the next step without purification.

[0819] Intermediate H was obtained by the synthesis method of intermediate B in Reference Example 1. The reaction scheme is as follows:

[0820] Example 6: Synthesis of the ammonium salt of compound 23 using intermediates F and H as raw materials

[0821] Using intermediates F and H as raw materials, the ammonium salt of compound 23 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0822] Example 7: Synthesis of the ammonium salt of compound 37 using intermediate B and intermediate I as raw materials

[0823] Using Intermediate B and Intermediate I as raw materials, the ammonium salt of Compound 37 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0824] Among them, intermediate I is obtained by the following steps:

[0825] Compound I1 (20.8 g, 40.0 mmol) and N2-isobutyrylguanine (8.8 g, 40.0 mmol) were weighed and suspended in DCE (208.0 mL). BSA (24.4 g, 120.0 mol) was added to the reaction mixture. The reaction mixture was heated to 70°C and stirred for 1 hour. The temperature was then lowered to 0°C, and TMSOTf (17.8 g, 80.0 mol) was added dropwise to the reaction mixture. After the addition was complete, the temperature was raised to 70°C and stirred for 3 hours. After cooling to room temperature, the reaction mixture was washed with saturated sodium bicarbonate solution. The organic phase was concentrated under reduced pressure and purified by column chromatography to yield intermediate I2 (18.3 g, 67.3%).

[0826] Intermediate I3-I was obtained by the synthesis method of intermediate G7-G in Reference Example 4. The reaction scheme is as follows:

[0827] Example 8: Synthesis of the ammonium salt of compound 38 using intermediate B and intermediate J as raw materials

[0828] Using Intermediate B and Intermediate J as raw materials, the ammonium salt of Compound 38 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0829] Among them, intermediate J is obtained by the following steps:

[0830] Intermediate I2 (15.0 g, 22.0 mmol) was weighed and dissolved in methanol (50 mL). Aqueous ammonia (150 mL) was added, and the mixture was heated to 40°C and allowed to react overnight. After completion of the reaction, the mixture was concentrated under reduced pressure and stripped twice with acetonitrile (100.0 mL). The crude product was purified by column chromatography to yield intermediate J1 (7.9 g, 88.5%).

[0831] Intermediate J1 (7.9 g, 19.5 mmol) was weighed and dissolved in DMF (79 mL). NaH (60%, 1.2 g, 29.2 mmol) was slowly added under ice-cooling. After returning to room temperature, the mixture was stirred for 0.5 hours. Iodomethane (4.1 g, 29.2 mmol) was added under ice-cooling and stirred at room temperature for 1 hour. After completion of the reaction, the reaction was quenched with saturated aqueous ammonium chloride (200 mL). The mixture was extracted twice with ethyl acetate (150 mL). The combined organic phases were washed with saturated aqueous sodium chloride (200 mL), concentrated under reduced pressure, and purified by column chromatography to yield Intermediate J2 (1.8 g, 21.9%).

[0832] Intermediate J3 was obtained by referring to the synthesis method of intermediate I3 in Example 7.

[0833] Intermediate J4-J was obtained by the synthesis method of intermediate I5-I in Reference Example 7. The reaction scheme is as follows:

[0834] Example 9: Synthesis of the ammonium salt of compound 44 using intermediate D and intermediate K as raw materials

[0835] Using intermediates D and K as raw materials, the ammonium salt of compound 44 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0836] Among them, intermediate K is obtained by the following steps:

[0837] Compound I1 (18.2 g, 35.0 mmol) and N6-benzoyl adenine (8.4 g, 35.0 mmol) were suspended in DCE (182.0 mL). BSA (21.4 g, 105.0 mol) was added to the reaction mixture. The reaction mixture was heated to 70°C and stirred for 1 hour. The temperature was then lowered to 0°C, and TMSOTf (15.6 g, 70.0 mol) was added dropwise. After the addition was complete, the temperature was raised to 70°C and stirred for 3 hours. After cooling to room temperature, the reaction mixture was washed with saturated sodium bicarbonate solution. The organic phase was concentrated under reduced pressure and purified by column chromatography to yield intermediate K1 (19.5 g, 79.5%).

[0838] Intermediate K1 (19.5 g, 27.8 mmol) was dissolved in methanol (195 mL). Sodium methoxide (0.15 g, 2.8 mmol) was added to the reaction mixture under a nitrogen atmosphere. The mixture was stirred at room temperature for 0.5 hours. After completion of the reaction, the pH of the reaction mixture was adjusted to neutral with 1 M HCl in an ice bath. The solvent was removed by concentration under reduced pressure, and the mixture was purified by column chromatography to yield Intermediate K2 (10.8 g, 79.4%).

[0839] Intermediate K2 (10.8 g, 22.1 mmol) was dissolved in DMF (108 mL). NaH (60%, 1.3 g, 33.1 mmol) was slowly added under ice-cooling. The mixture was allowed to return to room temperature and stirred for 0.5 hours. Iodomethane (4.7 g, 33.1 mmol) was added under ice-cooling and stirred at room temperature for 1 hour. After completion of the reaction, the reaction was quenched with saturated aqueous ammonium chloride (300 mL). The mixture was extracted twice with ethyl acetate (200 mL). The combined organic phases were washed with saturated aqueous sodium chloride (300 mL), concentrated under reduced pressure, and purified by column chromatography to yield Intermediate K3 (6.3 g, 56.7%).

[0840] Intermediate K4-K was obtained by the synthesis method of intermediate H6-6 in Reference Example 5. The reaction scheme is as follows:

[0841] Example 10: Synthesis of the ammonium salt of compound 45 using intermediates F and K as raw materials

[0842] Using intermediates F and K as raw materials, the ammonium salt of compound 45 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0843] Example 11: Synthesis of the ammonium salt of compound 54 using intermediate B and intermediate L as raw materials

[0844] Using Intermediate B and Intermediate L as raw materials, the ammonium salt of Compound 54 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0845] The intermediate L2-L was obtained by the synthesis method of the intermediate F1-F in Reference Example 3. The reaction scheme is as follows:

[0846] Example 12: Synthesis of the ammonium salt of compound 55 using intermediate D and intermediate M as raw materials

[0847] Using intermediates D and M as raw materials, the ammonium salt of compound 55 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0848] Intermediate M was obtained by the synthesis method of intermediate B in Reference Example 1. The reaction scheme is as follows:

[0849] Example 13: Synthesis of the ammonium salt of compound 56 using intermediate B and intermediate N as raw materials

[0850] Using intermediates B and N as raw materials, the ammonium salt of compound 56 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0851] The intermediate N2-N was obtained by referring to the synthesis method of the intermediate L2-L in Example 11. The reaction scheme is as follows:

[0852] Example 14: Synthesis of the ammonium salt of compound 57 using intermediate F and intermediate M as raw materials

[0853] Using intermediates F and M as raw materials, the ammonium salt of compound 57 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0854] Example 15: Synthesis of the ammonium salt of compound 76 using intermediate B and intermediate O as raw materials

[0855] Using Intermediate B and Intermediate O as raw materials, the ammonium salt of Compound 76 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0856] Among them, intermediate O1-O was obtained by synthesizing intermediate G1-G in Reference Example 4. The reaction scheme is as follows:

[0857] Example 16: Synthesis of the ammonium salt of compound 81 using intermediate D and intermediate P as raw materials

[0858] Using Intermediate D and Intermediate P as raw materials, the ammonium salt of Compound 81 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0859] Among them, the intermediate P2-P was obtained by synthesizing the intermediate H2-H in Reference Example 5. The reaction scheme is as follows:

[0860] Example 17: Synthesis of the ammonium salt of compound 16 using intermediate B and intermediate R as raw materials

[0861] Using intermediates B and R as raw materials, the ammonium salt of compound 16 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0862] Among them, the intermediate R is obtained by the synthesis method of intermediate G in Reference Example 4. The reaction scheme is as follows:

[0863] Example 18: Synthesis of the ammonium salt of compound 100 using intermediates 100-10 and 100-12 as raw materials

[0864] Using intermediates 100-10 and 100-12 as raw materials, the ammonium salt of compound 100 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0865] Among them, intermediate 100-10 is obtained by the following steps:

[0866] Compound 100-1 (15.0 g, 40.5 mmol) was dissolved in DMF (150.0 mL). Imidazole (2.8 g, 121.5 mmol) and TBSCl (15.3 g, 101.3 mmol) were added at room temperature and stirred for 16 hours. After the reaction, the reaction mixture was poured into ice water, where solid precipitated. The filter cake was filtered, washed with water, and dried to yield intermediate 100-2 (22.9 g, 94.3%).

[0867] Intermediate 100-2 (22.9 g, 38.2 mmol) was dissolved in a mixture of THF and water (4:1, 120.0 mL). The reaction mixture was cooled to 0°C, TFA (23 g) was added dropwise, and stirring was continued for 2 hours. After the reaction, the pH was adjusted to neutral with 10% aqueous sodium bicarbonate. The reaction mixture was extracted twice with ethyl acetate (150 mL). The combined organic phases were washed with saturated aqueous sodium chloride (200 mL), concentrated under reduced pressure, and purified by column chromatography to afford Intermediate 100-3 (15.1 g, 81.3%).

[0868] Intermediates 100-4, 100-5, and 100-6 were obtained by synthesizing intermediates G4-G6 in Reference Example 4.

[0869] Intermediate 100-6 (5 g, 8.1 mmol) was dissolved in acetonitrile (60.0 mL). Trimethylsilyl bromide (12.4 g, 81.0 mmol) was added to the reaction mixture at room temperature. After stirring overnight at room temperature, water (50.0 mL) was added to the reaction mixture and stirring continued for 5 hours. After completion of the reaction, the mixture was concentrated under reduced pressure to obtain the crude product of Intermediate 100-7, which was carried on to the next step without purification.

[0870] Dissolve the crude intermediate 100-7 from the previous step in concentrated aqueous ammonia (50.0 mL) and methanol (20.0 mL), heat to 40°C, and stir for 12 hours. After the reaction, concentrate under reduced pressure and distill twice with water (100.0 mL) to remove most of the aqueous ammonia to obtain an aqueous solution of intermediate 100-8, which was carried on to the next step without purification.

[0871] The pH of the aqueous solution of intermediate 100-8 was adjusted to 4 with acetic acid. The reaction solution was cooled to 4°C and dimethyl sulfate (8.2 g, 64.8 mmol) was slowly added dropwise. During the process, the pH was adjusted between 4 and 5 with 2M sodium hydroxide. The reaction was monitored by HPLC. After the reaction, it was purified by preparative chromatography, concentrated under reduced pressure, and lyophilized to obtain intermediate 100-9 (1.8 g, 56.5%, total yield for three steps).

[0872] Intermediate 100-9 (1.8 g, 4.6 mmol) was weighed and suspended in DMF (20.0 mL). Triphenylphosphine (2.4 g, 9.2 mmol), 2,2'-disulfide dipyridine (2.0 g, 9.2 mmol), imidazole (3.1 g, 46.0 mmol), and triethylamine (0.9 g, 9.2 mmol) were added sequentially at room temperature. The mixture was stirred at room temperature under a nitrogen atmosphere for 10 hours. After completion of the reaction, the reaction mixture was slowly added to a solution of sodium perchlorate (18.4 mmol) in acetone (100.0 mL). The precipitated solid was filtered and the filter cake was washed thoroughly with acetone until it turned white. The solvent was removed under reduced pressure to yield Intermediate 100-10 (1.8 g, 85.9%).

[0873] The reaction process is as follows:

[0874] Among them, intermediate 100-12 is obtained by the following steps:

[0875] Intermediate B (3.2 g, 4.6 mmol) was weighed and suspended in DMF (35.0 mL). Triphenylphosphine (2.4 g, 9.2 mmol), 2,2'-disulfide dipyridine (2.0 g, 9.2 mmol), imidazole (3.1 g, 46.0 mmol), and triethylamine (0.9 g, 9.2 mmol) were added sequentially at room temperature. The mixture was stirred at room temperature under a nitrogen atmosphere for 10 hours. After the reaction, the reaction mixture was slowly added to a solution of sodium perchlorate (18.4 mmol) in acetone (100.0 mL). The precipitated solid was filtered and the filter cake was washed thoroughly with acetone until it turned white. The solvent was removed under reduced pressure to obtain Intermediate 100-11 (3.1 g, 89.1%).

[0876] Intermediate 100-11 (3.1 g, 4.1 mmol) and tributylamine phosphate (4.6 g, 16.4 mmol) were weighed and suspended in DMF (30.0 mL). Under a nitrogen atmosphere, the mixture was cooled to 0°C, and zinc chloride (4.5 g, 32.8 mmol) was added portionwise. The mixture was then stirred at room temperature for 5 hours. After the reaction, the mixture was diluted with water, loaded onto a DEAE Sephadex, and eluted with a 0-1.0 M aqueous TEAB gradient. The pure fractions were collected, concentrated under reduced pressure, and lyophilized to yield the triethylamine salt of intermediate 100-12 (2.9 g, 64.5%).

[0877] The reaction process is as follows:

[0878] Example 19: Synthesis of the ammonium salt of compound 106 using intermediate 106-16 and intermediate 100-12 as raw materials

[0879] Using intermediates 106-16 and 100-12 as raw materials, the ammonium salt of compound 106 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0880] Among them, intermediate 106-16 is obtained by the following steps:

[0881] A mixture of compound 106-1 (57.0 g, 0.3 mol), TBDPSCl (105.0 g, 0.37 mol), and imidazole (32.2 g, 0.6 mol) in DMF (500.0 mL) was stirred at room temperature for 3 hours. After the reaction was complete, the solvent was removed by concentration under reduced pressure. The residue was dissolved in ethyl acetate (1.0 L), washed with water (400.0 mL x 2) and brine (300.0 mL), dried over anhydrous sodium sulfate, and concentrated to dryness under reduced pressure to obtain the crude intermediate 106-2 (129.1 g, 100%), which was used directly in the next reaction without purification.

[0882] Intermediate 106-2 (129 g, 0.3 mol) was weighed and dissolved in acetonitrile (1.2 L). IBX (126 g, 0.45 mol) was added and the mixture was heated to 90°C and stirred overnight. After the reaction, the mixture was cooled to room temperature and filtered. The filter cake was washed with a small amount of acetonitrile and the filtrate was concentrated to dryness to obtain the crude intermediate 106-3 (125.2 g, 97.8%), which was used directly in the next reaction without purification.

[0883] To a solution of lithium diisopropylamide (2M in THF, 0.44 mol) in THF (1.0 L) was added methyltriphenylphosphonium bromide (113.9 g, 0.32 mol) portionwise. The reaction mixture was heated to 50°C for half an hour, and then intermediate 106-3 (125.2 g, 0.29 mol) in THF (400.0 mL) was added dropwise to the reaction mixture. The reaction mixture was maintained at 50°C for 1 hour. After the reaction was completed, the mixture was cooled to room temperature. The reaction mixture was poured into 1.5 L of saturated aqueous ammonium chloride. After separation, the aqueous phase was extracted with ethyl acetate (300.0 mL). The combined organic phases were dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to yield intermediate 106-4 (99.6 g, 80.9%).

[0884] A solution of Intermediate 106-4 (99.6 g, 0.23 mol) in THF (800.0 mL) was slowly added dropwise to a BH3-THF solution (1 M, 0.46 mol) at 0°C. The reaction was stirred at room temperature for 1 hour. THF / H2O (1:1, 800.0 mL) was slowly added dropwise at 0°C, followed by the dropwise addition of 2M NaOH aqueous solution (1.0 L) and 30% H2O2 (1.0 L, 4 eq). The reaction was returned to room temperature and stirred for 2 hours. After the reaction, the reaction mixture was poured into ice water and extracted with ethyl acetate (300.0 mL x 3). The combined organic phases were dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to yield Intermediate 106-5 (75.2 g, 74.9%).

[0885] Intermediate 106-5 (75.2 g, 0.17 mol) was dissolved in THF (750.0 mL) and cooled to 0°C. NaH (60%, 10.2 g, 0.26 mol) was added portionwise to the reaction mixture. After addition, the mixture was returned to room temperature and stirred for 0.5 hours. Iodomethane (28.4 g, 0.2 mol) was added dropwise to the reaction mixture at 0°C and returned to room temperature and stirred for 3 hours. After completion of the reaction, the reaction mixture was quenched with saturated ammonium chloride (500.0 mL) and extracted with ethyl acetate (300.0 mL x 2). The organic phases were combined, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to obtain Intermediate 106-6 (63.9 g, 0.1482.3%).

[0886] Intermediate 106-6 (63.9 g, 0.14 mol) was dissolved in acetic acid (180.0 mL). Acetic anhydride (57.2 g, 0.56 mol) was added at room temperature, and the temperature was cooled to below 10°C. Concentrated sulfuric acid (6.4 mL) was added dropwise to the reaction mixture. Stirring was continued overnight at room temperature. The reaction mixture was diluted with DCM (800.0 mL) and washed sequentially with water, saturated aqueous sodium bicarbonate solution, and saturated brine, dried over anhydrous sodium sulfate, and the organic phase was concentrated under reduced pressure to obtain the crude intermediate 106-7, which was used directly in the next step without purification.

[0887] The crude compound 106-7 obtained in the previous step and isobutyryl-guanine (31.0 g, 0.14 mol) were suspended in DCE (600.0 mL). BSA (56.9 g, 0.28 mol) was added to the reaction mixture. The reaction mixture was heated to 70°C and stirred for 1 hour. The temperature was then lowered to 0°C, and TMSOTf (77.8 g, 0.35 mol) was added dropwise. After the addition was complete, the temperature was raised to 70°C and stirred for 3 hours. After cooling to room temperature, the reaction mixture was washed with saturated sodium bicarbonate solution. The organic phase was concentrated under reduced pressure and purified by column chromatography to yield intermediate 106-8 (57.5 g, 62.1%).

[0888] Intermediate 106-8 (57.5 g, 86.9 mmol) was dissolved in anhydrous DCM (550.0 mL). 3HF-TEA (42.0 g, 0.26 mol) was added and stirred at room temperature for 10 hours. After completion of the reaction, the reaction mixture was washed with water, and the aqueous phase was extracted once with ethyl acetate. The organic phases were combined, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Purification by column chromatography afforded Intermediate 106-9 (31.2 g, 84.7%).

[0889] Intermediates 106-10 to 106-16 were obtained by referring to the synthetic method of intermediates 100-4 to 100-10 in Example 18.

[0890] The reaction process is as follows:

[0891] Example 20: Synthesis of the ammonium salt of compound 114 using intermediate 114-11 and intermediate 100-12 as raw materials

[0892] Using intermediates 114-11 and 100-12 as raw materials, the ammonium salt of compound 114 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0893] Among them, intermediate 114-12 is obtained by the following steps:

[0894] Intermediate 106-5 (88.5 g, 0.2 mol) was weighed and dissolved in acetonitrile (880.0 mL). IBX (84 g, 0.3 mol) was added and the mixture was heated to 90°C and stirred overnight. After the reaction, the mixture was cooled to room temperature and filtered. The filter cake was washed with a small amount of acetonitrile and the filtrate was concentrated to dryness to obtain the crude intermediate 114-1 (83.7 g, 95.1%), which was used directly in the next reaction without purification.

[0895] Intermediate 114-1 (83.7 g, 0.19 mol) was dissolved in DCM (800.0 mL), cooled to 0°C, and diethylaminosulfur trifluoride (91.8 g, 0.57 mol) was added dropwise to the reaction mixture. The mixture was allowed to react at 0°C for 3 hours. After completion of the reaction, the reaction mixture was slowly poured into a saturated aqueous sodium bicarbonate solution (1.0 L). After separation, the aqueous phase was extracted with DCM (400.0 mL x 2). The combined organic phases were dried over anhydrous sodium sulfate and concentrated under reduced pressure. Purification by column chromatography afforded Intermediate 114-2 (67.5 g, 76.8%).

[0896] Intermediates 114-3 to 114-12 were obtained by referring to the synthetic method of intermediates 106-7 to 106-16 in Example 19.

[0897] The reaction process is as follows:

[0898] Example 21: Synthesis of the ammonium salt of compound 117 using intermediate 117-2 and intermediate O as raw materials

[0899] Using intermediate 117-2 and intermediate O as raw materials, the ammonium salt of compound 117 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0900] Among them, intermediate 117-2 is obtained by the following steps:

[0901] 2'OEt-rA phosphoramidite monomer (91.0 g, 0.1 mol) and N2-isobutyryl-2',3'acetylguanosine (43.7 g, 0.1 mol) were weighed and dissolved in DCM (900.0 mL). Tetrazole (12.6 g, 0.18 mol) was added under a nitrogen atmosphere. Stir at room temperature for 2 hours. After the reaction, DDTT (61.6 g, 0.3 mol) was added to the reaction mixture, and the reaction continued at room temperature for 3 hours. A solution of trichloroacetic acid (49.0 g, 0.3 mol) in DCM (0.2 L) was added dropwise to the reaction mixture, and the reaction continued at room temperature for 2 hours. The reaction mixture was washed with 10% aqueous sodium bicarbonate solution and saturated brine, respectively. The organic phase was concentrated under reduced pressure and purified by column chromatography to obtain intermediate 117-1 (59.4 g, 61.4%).

[0902] Intermediate 117-1 (59.4 g, 61.4 mmol) and bis(2-cyanoethyl)-N,N-diisopropylphosphoramidite (25.0 g, 92.1 mmol) were dissolved in DCM (600.0 mL). Tetrazole (6.4 g, 92.1 mmol) was added under a nitrogen atmosphere. The mixture was stirred at room temperature for 2 hours. After the reaction, aqueous tert-butyl hydroperoxide (0.18 mol, 70%) was added dropwise to the reaction mixture, and the reaction was continued at room temperature for 1 hour. The reaction mixture was washed with 10% aqueous sodium sulfite, 10% aqueous sodium bicarbonate, and saturated brine, respectively. The organic phase was concentrated under reduced pressure, dissolved in methanol (0.5 L) and aqueous ammonia (1.0 L), and stirred at room temperature overnight. The solvent was removed by concentration, and the mixture was diluted with water, loaded onto DEAE Sephadex, and eluted with a linear gradient of 0-1.0 M TEAB eluent. The mixture was concentrated to obtain the triethylamine salt of intermediate 117-2 (38.0 g, 84.1%).

[0903] The reaction process is as follows:

[0904] Example 22: Synthesis of the ammonium salt of compound 120 using intermediate 120-13 and intermediate 100-12 as raw materials

[0905] Using intermediates 120-13 and 100-12 as raw materials, the ammonium salt of compound 120 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0906] Among them, intermediate 120-13 is obtained by the following steps:

[0907] Intermediate 106-5 (50.0 g, 0.11 mol) and triethylamine (16.2 g, 0.16 mol) were weighed and dissolved in DCM (500.0 mL). The temperature was cooled to 0°C, and methylsulfonyl chloride (13.7 g, 0.12 mol) was added dropwise to the reaction mixture. The mixture was allowed to react at room temperature for 5 hours. After the reaction was complete, the reaction mixture was washed with 5% aqueous sodium bicarbonate (300.0 mL) and saturated aqueous sodium chloride (300.0 mL), respectively. The organic phase was dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure to obtain crude intermediate 120-1 (56.5 g, 98.7%), which was used directly in the next step without purification.

[0908] The crude intermediate 120-1 (56.5 g, 0.108 mol) was dissolved in DMF (550.0 mL). Sodium azide (28.2 g, 0.43 mol) was added at room temperature, and the mixture was heated to 80°C and stirred overnight. After completion of the reaction, the reaction solution was cooled to room temperature, water (1.5 L) was added, and extraction was performed with ethyl acetate (300.0 mL x 3). The organic phases were combined, washed with saturated sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Purification by column chromatography afforded 120-2 (39.5 g, 78.3%).

[0909] Intermediates 120-3 to 120-8 were obtained by referring to the synthesis method of intermediates 114-3 to 114-8 in Example 20.

[0910] Intermediate 120-8 (10.0 g, 18.4 mmol) and triethylamine (2.8 g, 27.6 mmol) were dissolved in DCM (100.0 mL). The temperature was cooled to 0°C, and acetyl chloride (1.7 g, 22.1 mmol) was added dropwise to the reaction mixture. The mixture was allowed to react at room temperature for 6 hours. After the reaction was complete, the reaction mixture was washed with saturated sodium chloride solution (150.0 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure. The mixture was purified by column chromatography to yield Intermediate 120-9 (9.7 g, 89.9%).

[0911] Intermediates 120-10 to 120-13 were obtained by referring to the synthetic method of intermediates 114-9 to 114-12 in Example 20.

[0912] The reaction process is as follows:

[0913] Example 23: Synthesis of the ammonium salt of compound 121 using intermediates 121-4 and 121-6 as raw materials

[0914] Using intermediates 121-4 and 121-6 as starting materials, the ammonium salt of compound 121 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0915] Among them, intermediate 121-4 is obtained by the following steps:

[0916] Intermediate 114-5 (10 g, 23.3 mmol) was dissolved in methanol (50.0 mL) and aqueous ammonia (100.0 mL) and stirred at room temperature overnight. After the reaction, the mixture was concentrated under reduced pressure and distilled twice with water (200.0 mL) and concentrated to dryness. The crude product was slurried with ethanol / water (5:1, 100.0 mL) and filtered. The filter cake was dried to obtain Intermediate 121-1 (7.1 g, 95.8%).

[0917] Intermediate 121-1 (7.1 g, 22.3 mmol) and tributylamine (7.4 g, 40.0 mmol) were dissolved in trimethyl phosphate (140.0 mL). After the mixture was cooled to -5°C, phosphorus oxychloride (6.8 g, 44.6 mmol) was added dropwise. The temperature was maintained for 3 hours. After completion of the reaction, the reaction was quenched with 1 M TEAB at 0°C. Purification by reverse-phase preparative chromatography afforded Intermediate 121-2 (7.2 g, 81.7%).

[0918] Intermediates 121-13 and 121-14 were obtained by referring to the synthesis method of intermediates 120-12 and 120-13 in Example 22.

[0919] The reaction process is as follows:

[0920] Intermediates 121-5 to 121-6 were obtained by referring to the synthetic method of intermediates 100-11 to 100-12 in Example 18.

[0921] The reaction process is as follows:

[0922] Example 24: Synthesis of the ammonium salt of compound 122 using intermediate 122-4 and intermediate 121-6 as raw materials

[0923] Using intermediates 122-4 and 121-6 as starting materials, the ammonium salt of compound 122 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0924] Among them, intermediates 122-1 to 122-4 were obtained by referring to the synthesis method of intermediates 121-1 to 121-4 in Example 23.

[0925] The reaction process is as follows:

[0926] Example 25: Synthesis of the ammonium salt of compound 124 using intermediate O and intermediate 124-9 as raw materials

[0927] Using Intermediate O and Intermediate 124-9 as raw materials, the ammonium salt of Compound 124 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0928] Among them, intermediates 124-2 to 124-9 were obtained by referring to the synthesis method of intermediate P2-P in Example 16. The reaction scheme is as follows:

[0929] Example 26: Synthesis of the ammonium salt of compound 126 using intermediate 126-12 and intermediate 100-12 as raw materials

[0930] Using intermediates 126-12 and 100-12 as raw materials, the ammonium salt of compound 126 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0931] Among them, intermediate 126-12 is obtained by the following steps:

[0932] Intermediate 106-2 (30.0 g, 70.0 mmol) and triethylamine (14.2 g, 0.14 mol) were dissolved in DCM (300.0 mL). The temperature was cooled to 0°C, and benzoyl chloride (12.8 g, 91.0 mmol) was added dropwise to the reaction mixture. The mixture was allowed to react at room temperature for 6 hours. After the reaction was complete, the reaction mixture was washed with saturated sodium chloride solution (300.0 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure. Purification by column chromatography afforded Intermediate 126-1 (33.5 g, 89.9%).

[0933] Intermediate 126-1 (33.5 g, 62.9 mmol) was weighed and dissolved in DCM (330.0 mL). Triethylamine hydrogen fluoride (40.5 g, 251.6 mmol) was added to the reaction mixture at room temperature and stirred overnight. After the reaction was complete, the reaction mixture was washed with saturated aqueous sodium chloride solution (300.0 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to dryness under reduced pressure. Purification by column chromatography afforded Intermediate 126-2 (16.9 g, 91.4%).

[0934] Intermediate 126-2 (16.9 g, 57.5 mmol) was weighed and dissolved in acetonitrile (100.0 mL) and water (60.0 mL). TEMPO (2.7 g, 17.2 mmol) was added at room temperature, followed by the addition of iodophenyldiacetic acid (37.0 g, 115.0 mmol) in portions. The mixture was stirred overnight at room temperature. After the reaction, the reaction mixture was concentrated under reduced pressure to remove the solvent and then dissolved in ethyl acetate (300.0 mL). The organic phase was washed with water (100.0 mL x 3). The organic phase was dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to yield Intermediate 126-3 (15.3 g, 86.3%).

[0935] Intermediate 126-3 (15.3 g, 49.6 mmol) was weighed and dissolved in dichloroethane (150.0 mL). Acetic acid (3.0 g, 49.6 mmol), anhydrous manganese acetate (6.6 g, 49.6 mmol), and iodophenyldiacetic acid (23.9 g, 74.4 mmol) were added to the reaction mixture at room temperature, followed by nitrogen substitution three times. The mixture was heated to 80°C and stirred for 6 hours. After completion of the reaction, the reaction mixture was quenched with 10% sodium thiosulfate. The mixture was diluted with ethyl acetate (500.0 mL) and stirred for another 0.5 hour. The organic phase was washed with water (300.0 mL), saturated aqueous sodium bicarbonate (300.0 mL), and saturated aqueous sodium chloride (300.0 mL), dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to afford 126-4 (10.9 g, 68.0%).

[0936] Intermediate 126-4 (10.9 g, 33.7 mmol) and Intermediate 126-5 (18.9 g, 134.8 mmol) were weighed and dissolved in dichloroethane (110.0 mL). After cooling the reaction mixture to -10°C, TMSOTf (22.5 g, 101.1 mmol) was added dropwise. The mixture was heated to 30°C and stirred overnight. The reaction mixture was slowly poured into saturated aqueous sodium bicarbonate (200.0 mL), stirred for 0.5 hours, and then separated. The aqueous phase was extracted with ethyl acetate (200.0 mL x 2), and the organic phases were combined. The organic phases were washed with saturated aqueous sodium chloride (300.0 mL), dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by column chromatography to yield Intermediate 126-6 (8.3 g, 61.4%).

[0937] Intermediates 126-7 to 126-8 were obtained by referring to the synthesis method of intermediates 120-3 to 120-4 in Example 22.

[0938] Intermediates 126-9 to 126-12 were obtained by referring to the synthetic method of intermediates 120-10 to 120-13 in Example 22.

[0939] The reaction process is as follows:

[0940] Example 27: Synthesis of the ammonium salt of compound 127 using intermediate 127-11 and intermediate 100-12 as raw materials

[0941] Using intermediates 127-11 and 100-12 as raw materials, the ammonium salt of compound 127 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0942] Among them, intermediate 127-1 was obtained by referring to the synthesis method of intermediate 106-6 in Example 19.

[0943] Intermediates 127-2 to 127-11 were obtained by referring to the synthetic method of intermediates 126-2 to 126-12 in Example 26.

[0944] The reaction process is as follows:

[0945] Example 28: Synthesis of the ammonium salt of compound 128 using intermediate 128-9 and intermediate D as raw materials

[0946] Using intermediate 128-9 and intermediate D as raw materials, the ammonium salt of compound 128 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0947] Among them, intermediates 128-2 to 128-4 were obtained by referring to the synthesis method of intermediates 127-3 to 127-5 in Example 27.

[0948] Intermediate 128-5 was obtained by referring to the synthesis method of intermediate K2 in Example 9.

[0949] Intermediates 128-6 to 128-9 were obtained by referring to the synthetic method of intermediates 124-6 to 124-9 in Example 25.

[0950] The reaction process is as follows:

[0951] Example 29: Synthesis of the ammonium salt of compound 129 using intermediate 126-12 and intermediate 129-4 as raw materials

[0952] Using intermediates 126-12 and 129-4 as starting materials, the ammonium salt of compound 129 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0953] Among them, intermediates 129-1 and 129-2 were obtained by referring to the synthesis method of intermediates 117-1 and 117-2 in Example 21.

[0954] Intermediates 129-3 and 129-4 were obtained by referring to the synthesis method of Intermediates 121-5 and 121-6 in Example 23.

[0955] The reaction process is as follows:

[0956] Example 30: Synthesis of the ammonium salt of compound 130 using intermediate 128-9 and intermediate F as raw materials

[0957] Using intermediate 128-9 and intermediate F as raw materials, the ammonium salt of compound 130 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0958] Example 31: Synthesis of the ammonium salt of compound 135 using intermediate 135-10 and intermediate 100-12 as raw materials

[0959] Using intermediates 135-10 and 100-12 as starting materials, the ammonium salt of compound 135 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0960] Among them, intermediates 135-1 to 135-10 were obtained by referring to the synthetic method of intermediates 127-2 to 127-11 in Example 27.

[0961] The reaction process is as follows:

[0962] Example 32: Synthesis of the ammonium salt of compound 138 using intermediate 138-12 and intermediate 100-12 as raw materials

[0963] Using intermediates 138-12 and 100-12 as raw materials, the ammonium salt of compound 138 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0964] Among them, intermediates 138-1 and 138-2 were obtained by referring to the synthesis method of intermediates 120-8 and 120-9 in Example 22.

[0965] Intermediates 138-3 and 138-12 were obtained by referring to the synthetic method of intermediates 135-1 to 135-10 in Example 31.

[0966] The reaction process is as follows:

[0967] Example 33: Synthesis of the ammonium salt of compound 139 using intermediate 139-4 and intermediate 126-12 as raw materials

[0968] Using intermediates 139-4 and 126-12 as starting materials, the ammonium salt of compound 139 was obtained by referring to the synthesis method of compound 15 in Example 4. The reaction scheme is as follows:

[0969] Among them, intermediates 139-1 to 139-4 were obtained by referring to the synthesis method of intermediates 129-1 to 129-4 in Example 29.

[0970] The reaction process is as follows:

[0971] Comparative Example 1: The ammonium salt of Comparative Example 1 was synthesized using Intermediate B and Intermediate D as raw materials.

[0972] Using Intermediate B and Intermediate D as raw materials, the ammonium salt of Comparative Example 1 was obtained by referring to the synthesis method of Compound 15 in Example 4. The reaction scheme is as follows:

[0973] Test example:

[0974] Test Example 1: Determination of mRNA in vitro transcription yield and capping efficiency

[0975] The capping compound of the embodiment is used to perform the IVT reaction of mRNA (mRNA in vitro synthesis reaction). First, calculate the volume of materials required for the system, and then add the sample (IVT reaction system is shown in Table 1). Sterile enzyme-free water is added to the system, followed by 10× buffer, NTPs, and cap analogs in sequence, mixed and centrifuged gently, then nuclease inhibitors, inorganic pyrophosphatase, T7 RNA polymerase, and linearized DNA template are added, mixed thoroughly and centrifuged gently, and incubated at 37 degrees Celsius. After 2 hours, 1U of DNaseI is added, and the incubation continues at 37 degrees Celsius for 30 minutes to remove the DNA template, and then the RNA is purified using a magnetic bead purification method. The purified mRNA is dissolved with sterile enzyme-free water and then quantitatively detected using NanodropOne.

[0976] Table 1 IVT reaction system

[0977] Liquid chromatography-mass spectrometry (LC-MS) is used to detect the IVT capping rate of mRNA with different initiation cap analogs. First, a labeled DNA probe is designed that matches the start base of the transcript mRNA, typically with a biotin marker. The streptavidin-labeled magnetic beads are washed and incubated with the synthesized DNA probe, mRNA, and 10× RNaseH reaction buffer at room temperature for 30 minutes, slowly mixing during incubation. Subsequently, 20μl of RNaseH (5U / μL) is added and incubated at 37°C for 3 hours, mixing every half hour. After incubation, the magnetic beads are washed and 100μL of 75% methanol heated to 80°C is added to the washed beads. The mixture is heated to 80°C on a hot plate for 3 minutes, then placed on a magnetic rack, the supernatant is aspirated, and the supernatant is dried in an evaporating centrifuge at room temperature for 45 minutes to a volume of 10μl. The sample was then resuspended in 50 μl of 100 μM EDTA / 1% MeOH and used for LC-MS analysis to determine the capping status of the RNA during the transcription reaction. Because capped and uncapped bases have distinct molecular weight differences, this molecular mass difference can be used to determine the capping rate of mRNA transcripts initiated with different cap analogs. The results are shown in Table 2.

[0978] Table 2 mRNA yield and capping efficiency

[0979] The experimental results show that when the capping compound of the present application is used to perform an IVT reaction of mRNA, the mRNA in vitro transcription yield and capping efficiency are comparable to those of Comparative Example 1.

[0980] Test Example 2: mRNA translation efficiency

[0981] Test method: Using the eGFP coding sequence as a DNA template, the cap analogs of Example and Comparative Example 1 were used as the starting point for in vitro transcription. The different mRNA products obtained were then transfected into 293T cells. 293T cells were transfected with (0.5-1)×10 5Cells were plated (24-well plates). During transfection, the cell density was generally 60-80%, and 2 μg of mRNA was transfected per well. The transfection reagent used was Lipofectamine MessengerMAX Transfection Reagent (Invitrogen), and the operation was performed according to its instructions. The transfected cells were placed in a 37-degree Celsius CO2 incubator. After 4-6 hours of transfection, fresh complete culture medium was replaced. After incubation in a 37-degree Celsius CO2 incubator for 72 hours, the fluorescence intensity of GFP was observed under a fluorescence microscope, and the fluorescence intensity ratio of the embodiment to the comparative example 1 was calculated based on the fluorescence intensity.

[0982] Table 3 mRNA translation efficiency

[0983] The experimental results show that after in vitro transcription starting with the cap analog of the present application and long-term incubation (72h) of the transfected cells, the translation efficiency of the mRNA is higher than that of Comparative Example 1. The above results show that the cap analog of the present application has higher translation efficiency at the cellular level, and the reason for the above effect may be that the mRNA is more stable in the cell.

[0984] Test Example 3: Study on the effect of decapping enzyme on the stability of cap structure

[0985] Take mRNA (200 μg) modified with different cap analogs, mix with 1 μl mRNA decapping enzyme (New England Biolabs) and 1×MDE buffer, and then react at 37°C for 45 minutes. The enzymatic reaction was subjected to PAGE electrophoresis and SYBR Green II (Lonza) staining, and the gel image after electrophoresis was observed on a Typhoon FLA 7000 (GE Healthcare) instrument. The ratio of the electrophoretic band intensity of capped RNA to that of decapped RNA was calculated using Image Quant (GE Healthcare) software, and the decapping efficiency after treatment with decapping enzyme (DCP2 enzyme) was calculated. Statistical tests were performed using the Dunnett test of KaleidaGraph (Synergy) software. As can be seen from the data in Table 4, after treatment with decapping enzyme (DCP2 enzyme), the decapping rate of the capping compound of the present application was significantly lower than that of Comparative Example 1.

[0986] Table 4 Decapping rate after decapping enzyme treatment

[0987] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A compound of formula (I'), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof: in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R'1 is selected from H or halogen; R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide; R'2 is selected from H or halogen; R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ; R4 is selected from halogen, OR f or R5 is selected from halogen or OR g ; R6 is selected from halogen or OR h ; R7 is selected from halogen or OR i ; X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CHO, OCH2, CH2CH2O, OCH2CH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2; and at least one of the following conditions is met: 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2, 2) X1 is CH2CH2O, OCH2, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2, 3) X2 is OCH2CH2, CH2O, C(=CH2)CH2, CH2C(=CH2), C(O)CH2 or C(S)CH2; 4) X3 is OCH2CH2; Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2; R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide; R' is selected from H or halogen; or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2; or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2; B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases; R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, preferably deuterium, halogen, C 1-6 Alkyl, C 1-6 Deuterated alkyl, C 1-6 Halogenated alkyl, preferably deuterium.

2. A compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof: in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R2 is selected from halogen or OR d ; R3 is selected from halogen or OR e ; R4 is selected from halogen, OR f or R5 is selected from halogen or OR g ; R6 is selected from halogen or OR h ; R7 is selected from halogen or OR i ; X1, X2, X3 and X4 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met: 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2, 2) X1 is CH2CH2O, 3) X2 is OCH2CH2; 4) X3 is OCH2CH2; Y1, Y2, Y3 and Y4 are independently selected from O, S, NH or CH2; R and R' are selected from H or halogen; or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2; B1, B2, B3 and B4 are independently selected from natural, modified or unnatural nucleobases; R a 、R b 、R c 、R d 、R e 、R f 、R g 、R h and R i independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

3. A compound of formula (I), or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof: in, X1, X2 and X3 are independently selected from O, S, CH2, CH2CH2, CH=CH, CH2O, OCH2, CH2CH2O or OCH2CH2; and at least one of the following conditions is met: 1) at least one of X1, X2 and X3 is selected from O, S, CH2 or CH2CH2, 2) X1 is CH2CH2O, 3) X2 is OCH2CH2; R X1 is OR a ; R X2 is OR b ; W is selected from O or S; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2; R1 is selected from halogen or OR c ; R2 is selected from halogen or OR d ; R3 is selected from halogen or OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; R and R' are selected from H or halogen; or R' and R3 are linked to form CH2O, OCH2, CH2CH2O or OCH2CH2; B1, B2 and B3 are independently selected from natural, modified or unnatural nucleobases; R a 、R b 、R c 、R d 、R e 、R f and R g independently selected from H, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl or 5-10 membered heteroaryl, wherein the C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-10 Cycloalkyl, 3-10 membered heterocyclic group, C 6-10 Aryl and 5-10 membered heteroaryl are optionally substituted by 1, 2, 3 or more halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; wherein any of the above groups is optionally further substituted by 1, 2, 3, 4, 5 or more of the following groups: deuterium, halogen, C 1-6 Alkyl, C 1-6 Halogenated alkyl, C 2-6 Alkenyl, C 2-6 Alkynyl, C 3-8 Cycloalkyl, 3-8 membered heterocyclic group, C 6-10 aryl or 5-10 membered heteroaryl.

4. The compound of any one of claims 1 to 3, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X1 is selected from O, S or CH2, preferably CH2; Preferably, X1 is selected from O, CH2, CH2CH2, CH═CH, CHO, OCH2, CH2CH2O, C(═CH2)CH2, CH2C(═CH2), C(O)CH2 or C(S)CH2, preferably O, CH2, CH2CH2, CH═CH, CHO, OCH2 or CH2CH2O, preferably CH2, CH2CH2, CHO, OCH2 or CH2CH2O.

5. The compound of any one of claims 1 to 4, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein X2 is selected from O, S or CH2, preferably CH2; Preferably, X2 is selected from CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2, preferably CH2, CH2CH2, CH═CH, CH2O, OCH2 or OCH2CH2.

6. The compound of any one of claims 1 to 5, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: X3 is selected from O, S or CH2, preferably CH2; Preferably, X3 is selected from CH2, CH2CH2, OCH2 or OCH2CH2, preferably OCH2.

7. A compound of formula (I) according to any one of claims 1 to 6, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: X4 is OCH2.

8. The compound of any one of claims 1 to 7, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 OH, C 1-6 Alkoxy or C 1-6 Haloalkoxy, preferably OH; Preferably, R X1 OR a ; R a Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Halogenated alkyl, preferably H.

9. The compound of any one of claims 1 to 8, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R X2 For OH.

10. The compound of any one of claims 1 to 9, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein W is O.

11. The compound of any one of claims 1 to 10, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: At least one of Y1, Y2 and Y3 is CH2; preferably, Y1 is CH2 and Y2 and Y3 are O; preferably, Y2 is CH2 and Y1 and Y3 are O; preferably, Y3 is CH2 and Y1 and Y2 are O; preferably, Y1 and Y2 are CH2 and Y3 is O; Preferably, at least one of Y1, Y2, Y3 and Y4 is CH2.

12. The compound of any one of claims 1 to 10, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: At least one of Y1, Y2 and Y3 is O, S or NH; preferably, one of Y1, Y2 and Y3 is O, S or NH; Preferably, at least one of Y1, Y2, Y3 and Y4 is O, S or NH; Preferably, Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y2 and Y3 are O; preferably Y1 and Y3 are O; Preferably, Y3 is O; preferably, Y4 is O.

13. The compound of any one of claims 1 to 12, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R1 is F or OH, preferably OH; Preferably, R1 is selected from halogen or OR c , preferably OR c ; Preferably, R c Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H; Preferably, R and R1 are optionally linked to form OCH2 or OCH2CH2, preferably OCH2; Preferably, R'1 is selected from H or F, preferably H.

14. The compound of any one of claims 1 to 13, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R2 is F, OH, C 1-6 Alkoxy or C 1-6 Halogenated alkoxy, preferably OH, C 1-6 Alkoxy or C 1-6 Haloalkoxy; wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 Halogenated alkoxy substituted; preferably OH or C 1-6 Alkoxy (e.g., OMe); Preferably, R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , preferably F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d wherein the alkyl and haloalkyl are optionally substituted by 1 group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Halogenated alkyl, preferably NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl (preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 haloalkyl), preferably C 1-6 Alkoxy or C 1-6 Halogenated alkoxy (preferably C 1-3 Alkoxy or C 1-3 haloalkoxy); Preferably, R2 is selected from halogen or OR d , preferably OR d ; Preferably, R d Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R d is H; Preferably, R'2 is selected from H or F, preferably H.

15. The compound of any one of claims 1 to 14, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, or R' and R3 are optionally linked to form CH2O or CH2CH2O, preferably CH2O; Preferably, R3 is F, C 1-6 Alkoxy or C 1-6 Haloalkoxy, wherein the C 1-6 Alkoxy and C 1-6 The haloalkoxy group is further C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; or R' and R3 are optionally linked to form CH2O or CH2CH2O, preferably CH2O; Preferably, R3 is F or C 1-6 Alkoxy, preferably C 1-6 Alkoxy (e.g., OMe); Preferably, R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ; R e Selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, wherein the alkyl, deuterated alkyl or haloalkyl is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 Haloalkoxy (C 1-3 Alkoxy or C 1-3 haloalkoxy) substituted; preferably R e It is a methyl group.

16. The compound of any one of claims 1 to 15, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R4 and R5 are OH; Preferably, R4 is 17. The compound of any one of claims 1 to 16, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R6 and R7 are OH.

18. The compound of any one of claims 1 to 17, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: R and R' are H.

19. The compound of any one of claims 1 to 18, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: B1 is natural or modified guanine, preferably alkyl-modified guanine, such as methyl-modified guanine.

20. The compound of any one of claims 1 to 19, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein: B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably, B2 is adenine, and B3 is guanine or uracil, preferably guanine; Preferably, B2, B3 and B4 are independently selected from adenine, guanine, cytosine, uracil and thymine, and the adenine, guanine, cytosine, uracil or thymine is optionally modified; Preferably, B2 is a natural or modified adenine or guanine; preferably, B2 is a natural or modified adenine, preferably a natural or alkyl (e.g., C 1-6 Alkyl, such as methyl) modified adenine, preferably adenine; Preferably, B3 is adenine, guanine or uracil, preferably guanine or uracil, preferably guanine; Preferably, B4 is adenine, guanine or uracil, preferably selected from guanine or uracil, preferably guanine.

21. The compound of any one of claims 1 to 20, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, having the general formula: wherein each group is as defined in any one of claims 1 to 20.

22. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (II-a): in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R2 is selected from halogen or OR d ; R3 is selected from halogen or OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; X2 is selected from CH2 or OCH2, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R' is selected from H or halogen; or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide; R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

23. The compound of claim 22, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 OR a , such as OH or OCH3, preferably OH; R X2 OR b , such as OH; W is selected from O or S, preferably O; R1 is selected from F or OR c , such as F or OH; preferably OR c , such as OH; R2 is OR d , such as OH, OCH3 or OCH2CH2OCH3, preferably OH or OCH3, preferably OH; R3 is selected from F or OR e , such as F, OCH3 or OCH2CH3; preferably OR e , such as OCH3 or OCH2CH3, preferably OCH3; R4 is OR f , such as OH; R5 is OR g , such as OH; X2 is selected from CH2 or OCH2, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are O; R' is H; or R' and R3 are optionally linked to form CH2O; B2 is adenine; B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H; R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

24. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (III-a): in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R2 is selected from halogen or OR d ; R3 is selected from halogen or OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; X1 is selected from CH2O or CH=CH, preferably CH2O; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide; R' is selected from H or halogen; or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil; R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

25. The compound of claim 24, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 OR a , such as OH; R X2 OR b , such as OH; W is O; R1 is OR c , such as OH; R2 is OR d , such as OH or OCH3, preferably OH; R3 is OR e , such as OCH3; R4 is OR f , such as OH; R5 is OR g , such as OH; X1 is selected from CH2O or CH=CH, preferably CH2O; X3 is OCH2; Y1, Y2 and Y3 are O; R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H; R' is H; B2 is adenine; B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

26. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (II-c-2): in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R'1 is selected from H or halogen; R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide; R'2 is selected from H or halogen; R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y2 and Y3 are O; R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide; R' is selected from H or halogen; or R and R1 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably OCH2 or OCH2CH2; or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O; R B1 Selected from C 1-3 Alkyl or C 1-3 deuterated alkyl; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally replaced by 1 C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Preferably B2 is natural or modified by 1 C 1-6 Alkyl-modified adenine, B3 is guanine or uracil; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide; R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

27. The compound of claim 26, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 is OR a ; R X2 is OR b ; W is selected from O or S, preferably O; R1 is selected from F or OR c , preferably OR c ; R'1 is selected from H or F, preferably H; R2 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 alkyl halide; R'2 is selected from H or F, preferably H; R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ; R4 is OR f ; R5 is OR g ; X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2; X3 is OCH2; Y1 is selected from O, S, NH or CH2, preferably O or CH2, preferably O; Y2 and Y3 are O; R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H; R' is H; or R and R1 are optionally linked to form OCH2; or R' and R3 are optionally linked to form CH2O; R B1 Selected from C 1-3 Alkyl or C 1-3 Deuterated alkyl, preferably C 1-3 alkyl; B2 is natural or covered by 1 C 1-3 Alkyl (e.g., methyl)-modified adenine; B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H; R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

28. The compound of claim 26 or 27, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 for OH; R X2 for OH; W is selected from O or S, preferably O; R1 is selected from F or OH, preferably OH; R'1 is selected from H or F, preferably H; R2 is selected from F, CH2F, CF2H, CHOCH3, CH2NHC(O)CH3, OH, OCH3, OCD3 or OCH2CH2OCH3, preferably CF2H, CHOCH3, CH2NHC(O)CH3, OH, OCH3 or OCD3; R'2 is selected from H or F, preferably H; R3 is selected from F, CF2H, OCH3, OCH2CH3, OCH2CH2OCH3, OCD3 or OCF3, preferably F, OCH3 or OCH2CH3, preferably OCH3 or OCH2CH3, preferably F or OCH3, preferably OCH3; R4 is OH; R5 is OH or OCH3, preferably OH; X2 is selected from OCH2, CH=CH or CH2CH2, preferably OCH2 or CH2CH2, preferably OCH2; X3 is OCH2; Y1 is selected from O, S, NH or CH2, preferably O or CH2, preferably O; Y2 and Y3 are O; R is selected from H or CHFCH3, preferably H; R' is H; or R and R1 are optionally linked to form OCH2; or R' and R3 are optionally linked to form CH2O; R B1 Selected from CH3 or CD3, preferably CH3; B2 is adenine or N6-methyladenine, preferably adenine; B3 is guanine or uracil, preferably guanine.

29. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (III-c): in, R X1 is OR a ; R X2 is OR b ; W is O or S, preferably O; R1 is selected from halogen or OR c ; R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide; R3 is selected from halogen or OR e , preferably OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; X1 is selected from CH2O, CH=CH or CH2CH2, preferably CH2O or CH2CH2, preferably CH2O; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; preferably Y1 and Y3 are O; R is selected from H, C 1-6 Alkyl or C 1-6 alkyl halide; R' is selected from H or halogen; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine and B3 is guanine or uracil; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide; R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

30. The compound of claim 29, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 OR a , such as OH; R X2 OR b , such as OH; W is O; R1 is OR c , such as OH; R2 is selected from C 1-3 Alkyl, C 1-3 Haloalkyl or OR d (preferably OH), wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Haloalkyl; for example CF2H, CH2NHC(O)CH3, OH or OCH3, preferably CF2H, CH2NHC(O)CH3 or OH; R3 is selected from F or OR e , such as F, OCH3, OCH2CH3 or OCH2CH2OCH3, preferably F or OCH3, preferably OCH3; R4 is OR f , such as OH; R5 is OR g , such as OH; X1 is selected from CH2O, CH=CH or CH2CH2, preferably CH2O or CH2CH2, preferably CH2O; X3 is OCH2; Y1 and Y3 are O; Y2 is selected from O, S, NH or CH2, preferably O or CH2, preferably O; R is selected from H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H; R' is H; B2 is adenine; B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl, preferably H; R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

31. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (Va): in, R X1 OR a , such as OH; R X2 OR b , such as OH; W is O or S, preferably O; R1 is selected from halogen or OR c , preferably OR c , such as OH; R2 is selected from halogen or OR d , preferably OR c , such as OH or OCH3, preferably OH; R3 is selected from halogen (preferably F) or OR e , such as F, OCH3 or OCH2CH3, preferably OCH3; R4 is selected from halogen or OR f , preferably OR f , such as OH; R5 is selected from halogen or OR g , preferably OR g , such as OH; X2 and X3 are OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R' is selected from H or halogen, preferably H; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

32. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (Vb): in, R X1 OR a , such as OH; R X2 OR b , such as OH; W is O or S, preferably O; R1 is halogen (preferably F) or OR c , such as F or OH; preferably OR c , such as OH; R2 is selected from halogen or OR d , preferably OR c , such as OH or OCH3, preferably OH; R3 is selected from halogen (preferably F) or OR e , preferably OR e , such as OCH3; R4 is selected from halogen or OR f , preferably OR f , such as OH; R5 is selected from halogen or OR g , preferably OR g , such as OH; X1 is selected from CH2O or CH=CH, preferably CH2O; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R is selected from H, C 1-6 Alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H; R' is selected from H or halogen, preferably H; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

33. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (II-d): in, R X1 is OR a ; R X2 is OR b ; W is selected from O or S; R1 is selected from halogen or OR c ; R'1 is selected from H or halogen; R2 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , wherein the C 1-6 Alkyl and C 1-6 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-6 Alkoxy, C 1-6 Haloalkoxy, NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 alkyl halide; R'2 is selected from H or halogen; R3 is selected from halogen, C 1-6 Alkyl, C 1-6 Haloalkyl or OR e ; R4 is selected from halogen or OR f ; R5 is selected from halogen or OR g ; X2 is selected from OCH2 or CH=CH, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R and R' are independently selected from H or halogen; or R' and R3 are optionally linked to form CH2O, OCH2, CH2CH2O or OCH2CH2, preferably CH2O or CH2CH2O; R B1 Selected from C 1-3 Alkyl or C 1-3 deuterated alkyl; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine, wherein the adenine, guanine, cytosine, uracil or thymine is optionally replaced by 1 C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Preferably B2 is natural or modified by 1 C 1-6 Alkyl-modified adenine, B3 is guanine or uracil; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 alkyl halide; R d and R e Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 haloalkyl, wherein the C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 The haloalkyl group is optionally replaced by 1 C 1-6 Alkoxy or C 1-6 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

34. The compound of claim 33, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 is OR a ; R X2 is OR b ; W is selected from O or S, preferably O; R1 is selected from F or OR c , preferably OR c ; R'1 is selected from H or F, preferably H; R2 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d , wherein the C 1-3 Alkyl and C 1-3 The haloalkyl group is optionally substituted with one group selected from the group consisting of: C 1-3 Alkoxy, C 1-3 Haloalkoxy, NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Halogenated alkyl, preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 alkyl halide; R'2 is selected from H or F, preferably H; R3 is selected from F, C 1-3 Alkyl, C 1-3 Haloalkyl or OR e , preferably F or OR e , preferably OR e ; R4 is OR f ; R5 is OR g ; X2 is selected from OCH2 or CH=CH, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O or CH2, preferably O; R and R' are H; or R' and R3 are optionally linked to form CH2O; R B1 Selected from C 1-3 Alkyl or C 1-3 Deuterated alkyl, preferably C 1-3 alkyl; B2 is natural or covered by 1 C 1-3 Alkyl (e.g., methyl)-modified adenine; B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R f and R g Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 alkyl halide; R d and R e Independently selected from H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 haloalkyl, wherein the C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 The haloalkyl group is optionally replaced by 1 C 1-3 Alkoxy or C 1-3 haloalkoxy substitution; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

35. The compound of claim 33 or 34, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein R X1 for OH; R X2 for OH; W is O; R1 is selected from F or OH, preferably OH; R'1 is selected from H or F, preferably H; R2 is selected from F, CH2F, CF2H, CH2OCH3, CH2NHC(O)CH3, OH or OCH3, preferably CF2H, CH2NHC(O)CH3, OH or OCH3; R'2 is selected from H or F, preferably H; R3 is selected from F, CF2H, OCH3, OCH2CH3 or OCF3, preferably F or OCH3, preferably OCH3; R4 is OH; R5 is OH; X2 is selected from OCH2 or CH=CH, preferably OCH2; X3 is OCH2; Y1, Y2 and Y3 are O; R and R' are H; or R' and R3 are optionally linked to form CH2O; R B1 Selected from CH3 or CD3, preferably CH3; B2 is adenine or N6-methyladenine, preferably adenine; B3 is guanine or uracil, preferably guanine.

36. The compound of claim 21, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, which has the structure of formula (III-d): in, R X1 OR a , such as OH; R X2 OR b , such as OH; W is O or S, preferably O; R1 is selected from halogen or OR c , preferably OR c , such as OH; R2 is selected from C 1-6 Alkyl, C 1-6 Haloalkyl or OR d , preferably C 1-3 Alkyl, C 1-3 Haloalkyl or OR d wherein the alkyl and haloalkyl are optionally substituted by one group selected from the group consisting of: NHC(O)C 1-6 Alkyl or NHC(O)C 1-6 Halogenated alkyl, preferably NHC(O)C 1-3 Alkyl or NHC(O)C 1-3 Haloalkyl, such as CF2H, CH2NHC(O)CH3, OH or OCH3; preferably OR d , such as OH or OCH3, preferably OCH3; R3 is selected from halogen or OR e , preferably OR e , such as OCH3; R4 is selected from halogen or OR f , preferably OR f , such as OH; R5 is selected from halogen or OR g , preferably OR g , such as OH; X1 is selected from CH2O; X3 is OCH2; Y1, Y2 and Y3 are independently selected from O, S, NH or CH2, preferably O or CH2, preferably O; R is selected from H, C 1-6 Alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl or C 1-3 Haloalkyl, preferably H; R' is selected from H or halogen, preferably H; B2 and B3 are independently selected from adenine, guanine, cytosine, uracil and thymine; preferably B2 is adenine; preferably B3 is guanine or uracil, preferably guanine; R a 、R b 、R c 、R d 、R e 、R f and R g Independently selected from H, C 1-6 Alkyl, C 1-6 Deuterated alkyl or C 1-6 Halogenated alkyl, preferably H, C 1-3 Alkyl, C 1-3 Deuterated alkyl or C 1-3 Haloalkyl; preferably R a 、R b 、R c 、R f and R g is H; Each of the radicals defined herein may be optionally substituted by D up to full deuteration.

37. The compound of any one of claims 1 to 36, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein the compound is selected from:

38. The compound of any one of claims 1-37, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, wherein B2 is fully complementary to the nucleobase at transcription template position +1 on the nucleic acid template, and B3 is fully complementary to the nucleobase at transcription template position +2 on the nucleic acid template.

39. An RNA molecule comprising at its 5' end a compound according to any one of claims 1 to 38, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof.

40. The RNA molecule of claim 39, which is an mRNA molecule.

41. A kit for capping RNA transcripts comprising a compound according to any one of claims 1 to 38, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof.

42. The kit of claim 41, further comprising an RNA molecule, preferably an mRNA molecule.

43. Use of a compound according to any one of claims 1 to 38, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof as an in vitro co-transcribed RNA capping agent. The use according to claim 43 , which is used for mRNA capping in an in vitro T7 RNA polymerase system.

45. A method for synthesizing RNA, comprising incubating the compound of any one of claims 1 to 38, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof with a nucleotide template to perform template transcription.

46. A complex comprising a compound of any one of claims 1 to 38, or a stereoisomer, tautomer or isotopic variant thereof, or a pharmaceutically acceptable salt thereof, and a DNA template, wherein the DNA template includes a promoter region comprising a transcription start site having a first nucleotide at nucleotide position +1 and a second nucleotide at nucleotide position +2; and B2 is complementary to the nucleobase at transcription template position +1 on the DNA template, and B3 is complementary to the nucleobase at transcription template position +2 on the DNA template.

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