Crosslinked artificial nucleic acid alna

Abstract

The present invention provides a novel crosslinked artificial nucleic acid and an oligomer that includes the same as a monomer. More specifically, the present invention provides a compound represented by general formula (I) (the symbols in the formula are as defined in the specification) or a salt thereof, and an oligonucleotide compound represented by general formula (I') (the symbols in the formula are as defined in the specification) or a salt thereof.

Description

Cross-linked artificial nucleic acid ALNA

[0001] This invention relates to an amino LNA monomer and an oligomer containing the same.

[0002] Nucleic acid-based therapies for treating diseases include antisense methods, antigene methods, aptamer-based methods, and siRNA-based methods. Of these, the antisense method is a technique that involves introducing an oligonucleotide (antisense strand) complementary to the mRNA or non-coding RNA involved in the disease from an external source, forming a double helix, thereby regulating the function of the RNA involved in the disease and treating or preventing the disease.

[0003] While various artificial nucleic acids have been developed as materials for nucleic acid drugs, challenges remain, such as avoiding toxicity in organs prone to nucleic acid drug accumulation, such as the liver and kidneys, after systemic administration, and ensuring sufficient drug efficacy. A truly game-changer molecule has yet to emerge. 2'-aminoLNA (Locked nucleic acid) (hereinafter referred to as "ALNA"), developed by Wengel et al. in 1998 (Patent Document 1 and Non-Patent Document 1), allows for the synthesis of diverse artificial nucleic acids through substituent modification from the 2' position. Many ALNA derivatives have been synthesized to date, primarily alkyl and acyl (Patent Documents 2-4 and Non-Patent Documents 2-11), and characteristic tissue distributions after systemic administration have been reported (Non-Patent Document 12). However, their pharmacological activity has been insufficient, and they have not been applied to pharmaceuticals until now.

[0004] By applying the efficient synthesis method for GuNA that we previously discovered (Patent Document 5 and Non-Patent Document 13), we synthesized a wide variety of new ALNA derivatives and conducted extensive screening specifically for pharmacological activity evaluation. As a result, we discovered novel artificial nucleic acids that exhibit superior in vitro and in vivo pharmacological activity compared to existing ALNAs, thus completing the present invention.

[0005] International Publication No. 99 / 014226, International Publication No. 2013 / 013068, International Publication No. 2014 / 124952, International Publication No. 2016 / 128583, International Publication No. 2017 / 047816

[0006] SK Singh et al., J. Org. Chem. 1998, Vol. 63, pp. 6078-6079; MD Sorensen et al., Chem. Commun. 2003, p. 2130; BR Babu et al., Chem. Commun. 2005, Vol. 13, pp. 1705-1707; T. Bryld et al., Nucleosides, Nucleotides & Nucleic Acids 2007, Vol. 26, pp. 1645-1647; M. Kalek et al., J. Am. Chem. Soc. 2007, Vol. 129, pp. 9392-9400; T. Umemoto et al., Org. Biomol. Chem. 2009, Vol. 7, pp. 1793-1797; MW Johannsen et al., Org. Biomol. Chem. 2011, Vol. 9, pp. 243-252 AS Jφrgensen et al., Chem. Commun. 2013, Vol. 49, pp. 10751-10753 IK Astakhova et al., Acc. Chem. Res. 2014, Vol. 47, pp. 1768-1777 C. Lou et al., Chem. Commun. 2015, Vol. 51, pp. 4024-4027 A. Ries et al., J. Org. Chem. 2016, Vol. 81, pp. 10845-10856 K. Fluiter et al., Chem. Bio. Chem. 2005, Vol. 6, pp. 1104-1109 H. Sawamoto et al., Org. Lett. 2018, Vol. 20, pp. 1928-1931

[0007] The present invention relates to novel cross-linked artificial nucleic acids, and oligomers containing them as monomers.

[0008] To solve the aforementioned problems, the present inventors conducted diligent research and, as a result, discovered novel 2'-aminoLNA and its salts, as well as oligomers containing it as a monomer, as shown below, thus completing the present invention.

[0009] In other words, the present invention relates to, but is not limited to, the following items [1] to

[33] . Item [1] General formula (I): [In the formula, B is the base portion of a nucleic acid which may be substituted with one or more substituents; R１ , R ２ , R ３ and R ４ are each independently a hydrogen atom or a C １－６ alkyl group which may be substituted with one or more substituents; R ５ and R ６ are each independently a hydrogen atom, a protecting group for a hydroxyl group, or a phosphate group which may be substituted; m is 1 or 2; X is the following formula (II-1), (II-2), or (II-3): a group represented by; the symbols described in formula (II-1), (II-2), or (II-3): indicate the bonding point with the 2'-amino group; R ７ and R ８ are each independently a hydrogen atom, a C １－６ alkyl group which may be substituted with one or more substituents, a C ２－６ alkenyl group which may be substituted with one or more substituents, a C ２－６ alkynyl group which may be substituted with one or more substituents, or an aromatic group which may be substituted with one or more substituents; A is an aromatic group; M is a sulfonyl group substituted with one substituent selected from the group consisting of a C １－６ alkyl group which may be substituted with one or more substituents and an aromatic group which may be substituted with one or more substituents. A compound represented by ], or a salt thereof. (Hereinafter, the compound represented by formula (I) or a salt thereof is referred to as "the compound of the present invention"). [2] B is adeninyl which may have one or more protecting groups, guanylyl which may have one or more protecting groups, cytosinyl which may have one or more protecting groups, 5-methylcytosinyl which may have one or more protecting groups, or urasilyl which may have one or more protecting groups, the compound according to [1], or a salt thereof. [3] R １ , R ２ , R ３ and R ４ are each independently a hydrogen atom; m is 1, the compound according to [1] or [2], or a salt thereof. [4] X is a group represented by formula (II-1); and R ７ and R８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ A compound according to any one of [1] to [3], or a salt thereof, which is an alkyl group or an aromatic group which may be substituted with one or more substituents. [5] R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－３ A compound described in [4], or a salt thereof, which is an alkyl group. [6] R ７ and R ８ The compound described in [5], or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is a methyl group. [7] R ７ and R ８ A compound according to [5], or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is an isopropyl group. [8] A compound according to any one of [1] to [3], or a salt thereof, wherein X is a group represented by formula (II-2); and A is a five- or six-membered heteroaryl ring containing one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms, which may be substituted with one or more substituents. [9] A is a five- or six-membered heteroaryl ring containing two or three heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms, which may be substituted with one or more substituents, and each substituent may be independently substituted with one or more halogen atoms. １－３ Alkyl alkyl groups, halogen atoms, and one or more C atoms １－３A compound according to [8], or a salt thereof, selected from the group consisting of amino groups which may be substituted with alkyl groups.

[10] A compound according to [9], or a salt thereof, selected from the group consisting of triazolyl groups, oxadiazolyl groups, thiadiazolyl groups, pyrimidinyl groups, and pyrazinyl groups, in which a 5 or 6-membered ring heteroaryl group may be substituted with one or more substituents.

[11] A compound according to

[10] , or a salt thereof, wherein the triazolyl group which may be substituted with one or more substituents is a 1,5-dimethyl-1,2,4-triazole-3-yl group.

[12] A compound according to

[10] , or a salt thereof, wherein the oxadiazolyl group which may be substituted with one or more substituents is a 5-methyl-1,2,4-oxadiazole-3-yl group.

[13] A compound according to

[10] , or a salt thereof, wherein the thiadiazolyl group which may be substituted with one or more substituents is a 3-methyl-1,2,4-thiadiazole-5-yl group.

[14] X is a group represented by formula (II-3); and M is C which may be substituted with one or more substituents. １－６ A compound according to any one of [1] to [3], or a salt thereof, wherein M is a sulfonyl group substituted with one substituent selected from the group consisting of alkyl groups and aryl groups which may be substituted with one or more substituents.

[15] A compound according to

[14] , or a salt thereof, wherein M is a sulfonyl group substituted with one substituent selected from the group consisting of methyl groups and phenyl groups.

[16] R ６ is a hydrogen atom or a DMTr group, and R ５ is a hydrogen atom or -P(O(CH) ２ ) ２ CN) (N(iPr) ２A compound or salt thereof as described in any one of [1] to

[15] .

[17] The following compounds: 3-[[(1R,4R,6R,7S)-4-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-6-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-methylsulfonyl-5-oxa-2-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 1 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 2 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate (Compound 3 of the present invention); N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (Compound 4 of the present invention); 3-[[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopronylamino)phosphanyl]oxypropanenitrile (Compound 5 of the present invention);N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl)oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 6 of the present invention); (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 7 of the present invention); (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 8 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(methylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (compound 9 of the present invention); (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 10 of the present invention);(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 11 of the present invention); (1R,3R,4R,7S)-3-(4-benzamide-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 12 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(isopropylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (compound 13 of the present invention); (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 14 of the present invention); (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 15 of the present invention);(1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 16 of the present invention); 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 17 of the present invention); 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 18 of the present invention); N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-6-formamidine (compound 19 of the present invention); N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (compound 20 of the present invention);3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 21 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 22 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 23 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanethoxy-(diisopropylamino)phosphanyl]oxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 24 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 25 of the present invention);N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-4-yl]benzamide (Compound 26 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamine)phosphanyl]oxypropanenitrile (Compound 27 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanothoxy-(diisopropylamino)phosphanyl]oxy-5-[(6-dimethylamino)pyrimidine-4-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 28 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)oxypropanenitrile (compound 29 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 30 of the present invention);3-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 31 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 32 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 33 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 34 of the present invention); N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-formamidine (compound 35 of the present invention);N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (compound 36 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 37 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 38 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 39 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 40 of the present invention);N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]dihydropyrimidine-2-one (compound 41 of the present invention); N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethylformamidine (compound 42 of the present invention); A compound selected from the group consisting of N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide (compound 43 of the present invention); and N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide (compound 44 of the present invention).

[0010] (Oligonocytes)

[18] General formula (I'): [In the formula, B is the base portion of a nucleic acid which may be substituted with one or more substituents; R １ , R ２ , R ３ and R ４ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ It is an alkyl group; m is 1 or 2; and X is the following formula (II'-1), (II'-2), or (II'-3): The base is represented by; the symbols listed in formula (II'-1), (II'-2), or (II'-3): indicates a bond site with a 2'-amino group; A is an aromatic group containing one or more heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms, which may be substituted with one or more substituents; M is a C which may be substituted with one or more substituents. １－６

[19] The oligonucleotide compound or salt thereof having one or more nucleosides represented by [formula (I')] (hereinafter, the compound or salt represented by formula (I') will be referred to as the "oligonucleotide compound of the present invention").

[18] The oligonucleotide compound or salt thereof according to

[18] , wherein B is adeninyl which may have one or more protecting groups, guaninyl which may have one or more protecting groups, cytosinyl which may have one or more protecting groups, 5-methylcytosinyl which may have one or more protecting groups, or urasilyl which may have one or more protecting groups.

[20] R １ , R ２ , R ３ and R ４ Each of the following is independently a hydrogen atom; m is 1, an oligonucleotide compound or salt thereof as described in

[18] or

[19] .

[21] (Urea-type compounds) X is a group represented by formula (II'-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ An oligonucleotide compound according to any one of

[18] to

[20] , or a salt thereof, wherein the oligonucleotide compound is an alkyl group or an aromatic group which may be substituted with one or more substituents.

[22] R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－３ An alkyl group, the oligonucleotide compound described in

[21] , or a salt thereof.

[23] R ７ and R ８An oligonucleotide compound according to

[22] , or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is a methyl group.

[24] R ７ and R ８ An oligonucleotide compound according to

[23] , or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is an isopropyl group.

[25] (aryl compound) An oligonucleotide compound according to any one of

[18] to

[20] , or a salt thereof, wherein X is a group represented by formula (II'-2); and A is a five- or six-membered heteroaryl group comprising one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms, which may be substituted with one or more substituents.

[26] A is a five- or six-membered heteroaryl group comprising two or three heteroatoms including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms and sulfur atoms, which may be substituted with one or more substituents, and each substituent may be independently substituted with one or more halogen atoms. １－３ Alkyl alkyl groups, halogen atoms, and one or more C atoms １－３

[25] An oligonucleotide compound or a salt thereof, selected from the group consisting of amino groups which may be substituted with alkyl groups.

[27] An oligonucleotide compound or a salt thereof, selected from the group consisting of triazolyl groups, oxadiazolyl groups, thiadiazolyl groups, pyrimidinyl groups, and pyrazinyl groups, wherein a 5- or 6-membered ring heteroaryl group may be substituted with one or more substituents.

[28] An oligonucleotide compound or a salt thereof, according to

[27] , wherein the triazolyl group which may be substituted with one or more substituents is a 1,5-dimethyl-1,2,4-triazole-3-yl group.

[29] An oligonucleotide compound or a salt thereof, according to

[27] , wherein the oxadiazolyl group which may be substituted with one or more substituents is a 5-methyl-1,2,4-oxadiazole-3-yl group.

[30] An oligonucleotide compound or a salt thereof, according to

[27] , wherein the thiadiazolyl group which may be substituted with one or more substituents is a 3-methyl-1,2,4-thiadiazole-5-yl group.

[31] (Sulfonamide-type compound) X is a group represented by formula (II'-3); and M may be substituted with one or more substituents C １－６ An oligonucleotide compound according to any one of

[18] to

[20] , or a salt thereof, wherein the sulfonyl group is substituted with one substituent selected from the group consisting of alkyl groups and aryl groups which may be substituted with one or more substituents.

[32] A compound according to any one of

[18] to

[31] , or a salt thereof, wherein M is a sulfonyl group substituted with one substituent selected from the group consisting of methyl groups and phenyl groups.

[33] A sulfurized oligonucleotide according to any one of

[18] to

[32] , or a salt thereof, wherein at least one of the phosphate bonds between nucleotides is a phosphorothioate bond.

[0011] The present invention makes it possible to produce novel 2'-amino LNA (hereinafter abbreviated as ALNA) and oligomers containing these ALNA as monomers (hereinafter abbreviated as ALNA oligomers). The ALNA oligomers of the present invention exhibit functional inhibition of target microRNAs and potent target gene knockdown activity in vitro. Furthermore, when administered to a living organism, they exhibit potent target gene knockdown activity in many organs (e.g., muscles), and therefore are expected to be used as novel nucleic acid drugs.

[0012] The present invention will be described in further detail below. All publications cited herein are incorporated herein by reference. (Definitions) First, the terms used herein are defined.

[0013] In this specification, the term "C which may be substituted with one or more substituents" is used. １－６ "Alkyl alkyl group" refers to a group with 1 to 6 carbon atoms (C １－６ ), preferably having 1 to 4 carbon atoms (C １－４ ), more preferably having 1 to 3 carbon atoms (C １－３ This includes any linear alkyl group having 1 to 6 carbon atoms, any branched alkyl group having 3 to 6 carbon atoms having the same or different branched chains, any cyclic alkyl group having 3 to 6 carbon atoms, and combinations thereof having 4 to 6 carbon atoms. For example, specific examples of any linear alkyl group having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, n-pentyl, and n-hexyl. Specific examples of any branched alkyl group having 3 to 6 carbon atoms having the same or different branched chains include i-propyl, i-butyl, tert-butyl, sec-butyl, neopentyl, and isopentyl. As for any cyclic alkyl group having 3 to 6 carbon atoms, 3-6 membered monocyclic cycloalkyl groups are preferred, and specific examples include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl, but are not limited to these. Examples of substituents include hydroxyl groups, halogen atoms, nitro groups, cyano groups, and C １－６ Alkyl alkyl group, C ２－６ Alkenyl group, C２－６ Alkynyl group, C １－６ Alkoxy group, aryl group, aryloxy group, one or more C １－３ amino groups, oxo groups, thioxo groups, and C groups that may be substituted with alkyl groups, and C groups that may be substituted with one or more halogen atoms. １－６ Examples include one or more (preferably one to three) identical or different groups selected from the group consisting of alkyl groups, but groups that are not affected by the oligomerization reaction conditions are preferred.

[0014] In this specification, the term "C which may be substituted with one or more halogen atoms" is used. １－３ "Alkyl alkyl" refers to the aforementioned term "C which may be substituted with one or more substituents". １－６ "Alkyl group" refers to a methyl, ethyl, n-propyl, or i-propyl group which may be substituted with one or more halogen atoms. Specific examples include perfluoroalkyl groups (e.g., trifluoromethyl, pentafluoroethyl, heptafluoropropyl).

[0015] In this specification, the term "C which may be substituted with one or more substituents" is used. ２－６ "Alkenyl" refers to a compound with 2 to 6 carbon atoms (C ２－６ ), preferably with 2 to 4 carbon atoms (C ２－４ ), more preferably having 2 to 3 carbon atoms (C ２－３This includes any linear alkenyl group, any branched alkenyl group having 3 to 6 carbon atoms having the same or different branched chains, any cyclic alkenyl group having 3 to 6 carbon atoms, and any combination thereof having 4 to 6 carbon atoms. For example, specific examples of any linear alkenyl group having 2 to 6 carbon atoms include ethenyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, and 1-hexenyl groups. Specific examples of any branched alkenyl group having 3 to 6 carbon atoms with the same or different branched chains include isopropenyl, 1-methyl-1-propenyl, 1-methyl-2-propenyl, 2-methyl-1-propenyl, 2-methyl-2-propenyl, and 1-methyl-2-butenyl groups. As for any cyclic alkenyl group having 3 to 6 carbon atoms, a 3-6 membered monocyclic cycloalkenyl group is preferred, and specific examples include cyclopropenyl, cyclobutenyl, cyclopentenyl, and cyclohexenyl groups, but are not limited to these. Examples of substituents include hydroxyl groups, halogen atoms, nitro groups, cyano groups, and C. １－６ Alkyl alkyl group, C ２－６ Alkenyl group, C ２－６ Alkynyl group, C １－６ Alkoxy group, aryl group, aryloxy group, one or more C １－３ amino groups, oxo groups, thioxo groups, and C groups that may be substituted with alkyl groups, and C groups that may be substituted with one or more halogen atoms. １－６ Examples include one or more (preferably one to three) identical or different groups selected from the group consisting of alkyl groups, but groups that are not affected by the oligomerization reaction conditions are preferred.

[0016] In this specification, the term "C which may be substituted with one or more substituents" is used. ２－６ "Alkynyl" refers to a group with 2 to 6 carbon atoms (C ２－６ ), preferably with 2 to 4 carbon atoms (C ２－４ ), more preferably having 2 to 3 carbon atoms (C ２－３), any linear alkynyl group, any branched alkynyl group having 3 to 6 carbon atoms with the same or different branched chains, any cyclic alkynyl group having 3 to 6 carbon atoms, and combinations thereof having 4 to 6 carbon atoms are included. For example, specific examples of any linear alkynyl group having 2 to 6 carbon atoms include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 1-pentynyl group, 2-pentynyl group, 3-pentynyl group, 4-pentynyl group, 1-hexynyl group, etc. Specific examples of any branched alkynyl group having 3 to 6 carbon atoms with the same or different branched chains include isopropynyl group, 1-methyl-1-propynyl group, 1-methyl-2-propynyl group, 2-methyl-1-propynyl group, 2-methyl-2-propynyl group, 1-methyl-2-butynyl group, etc. And as any cyclic alkynyl group having 3 to 6 carbon atoms, a 3- to 6-membered monocyclic cycloalkynyl group is preferred, and specific examples include cyclobutinyl group, cyclopentynyl group, cyclohexynyl group, etc., but are not limited thereto. Examples of substituents include hydroxyl group, halogen atom, nitro group, cyano group, C １－６ alkyl group, C ２－６ alkenyl group, C ２－６ alkynyl group, C １－６ alkoxy group, aryl group, aryloxy group, amino group optionally substituted with one or more C １－３ alkyl groups, oxo group, thioxo group, and C １－６ alkyl group optionally substituted with one or more halogen atoms, and one or more (preferably 1 to 3) identical or different groups selected from the group consisting of, but groups not affected by the oligomerization reaction conditions are preferred.

[0017] In the present specification, the term "aromatic group optionally substituted with one or more substituents" means including both aryl groups and heteroaryl groups. The aryl group and heteroaryl group are each independently optionally substituted with one or more substituents. Examples of substituents include hydroxyl group, halogen atom, nitro group, cyano group, C[[ID=1⑥]] １－６ [[ID=1⑦]]alkyl group optionally substituted with one or more substituents, C２－６ An alkenyl group, a C which may be substituted with one or more substituents ２－６ An alkynyl group, a hydroxyl group, a C １－６ An alkoxy group, an aryloxy group, one or more C １－３ An amino group which may be substituted with one or more alkyl groups, a C which may be substituted with one or more halogen atoms １－６ One or more (or preferably 1 to 3) identical or different groups selected from the group consisting of an alkenyl group, an alkynyl group, a hydroxyl group, a C alkoxy group, an aryloxy group, an amino group which may be substituted with one or more alkyl groups, a C alkyl group which may be substituted with one or more halogen atoms, and an aryl group are mentioned. Preferably, a C alkyl group which may be substituted with one or more substituents １－６ An alkyl group, one or more C １－３ An amino group which may be substituted with one or more alkyl groups, and a halogen atom are mentioned. More preferably, a trifluoromethyl group, a dimethylamino group, a chloro atom, etc. are mentioned. A group not affected by the reaction conditions of oligomerization is preferred.

[0018] In this specification, the term "aryl group" is a functional group or substituent derived from an aromatic hydrocarbon, including those consisting of multiple rings. Specifically, it means a monovalent group having 6 to 14 carbon atoms composed of one or more 5-membered rings and / or 6-membered rings obtained by removing one hydrogen atom from an aromatic hydrocarbon group. Preferably, aryl of a 5-membered ring or 6-membered ring is mentioned. Specific examples of the aryl group include phenyl, indenyl, naphthyl, phenanthrenyl, anthracenyl, etc. Further, examples of the substituent of the aryl group include a hydroxyl group, a halogen atom, a nitro group, a cyano group, a C alkyl group which may be substituted with one or more substituents, a C alkenyl group which may be substituted with one or more substituents, a C alkynyl group, a C alkoxy group, an aryloxy group, an amino group, an amino group which may be substituted with one or more C alkyl groups, and an aryl group. One or more (or preferably 1 to 3) identical or different groups selected from the group consisting of an alkyl group, an alkenyl group, an alkynyl group, a hydroxyl group, a C alkoxy group, an aryloxy group, an amino group, an amino group which may be substituted with one or more C alkyl groups, and an aryl group are mentioned. Preferably, a C alkyl group which may be substituted with one or more substituents １－６ An alkyl group, a C which may be substituted with one or more substituents ２－６ An alkenyl group, a C which may be substituted with one or more substituents ２－６ An alkynyl group, a C １－６ An alkoxy group, an aryloxy group, an amino group, one or more C １－３ An amino group which may be substituted with one or more alkyl groups, and an aryl group. One or more (or preferably 1 to 3) identical or different groups selected from the group consisting of an alkyl group, an alkenyl group, an alkynyl group, a hydroxyl group, a C alkoxy group, an aryloxy group, an amino group, an amino group which may be substituted with one or more C alkyl groups, and an aryl group are mentioned. Preferably, a C alkyl group which may be substituted with one or more substituents １－６ An alkyl group, one or more C １－３Examples include amino groups which may be substituted with alkyl groups, and halogen atoms, more preferably trifluoromethyl groups, dimethylamino groups, and chloro atoms, but groups which are not affected by the oligomerization reaction conditions are preferred. Specific examples of aryl groups which may be substituted with one or more substituents include 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 2,6-dimethylphenyl, 2,4-dimethylphenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2,4-dichlorophenyl, 2,5-dichlorophenyl, 2,6-dichlorophenyl, 2-bromophenyl, 4-methoxyphenyl, 4-chloro-2-nitrophenyl, 4-nitrophenyl, 2-nitrophenyl, 2,4-dinitrophenyl, 2-trifluoromethylphenyl, 3-trifluoromethylphenyl, 4-trifluoromethylphenyl, 2-dimethylaminophenyl, 3-dimethylaminophenyl, 4-dimethylaminophenyl, and biphenyl.

[0019] In this specification, the term "heteroaryl group" means a monovalent group obtained by removing one hydrogen atom from any heteroaromatic compound having 5 to 12 carbon atoms, consisting of one or more 5-membered rings and / or 6-membered rings, which contain one or more heteroatoms (e.g., a nitrogen atom, an oxygen atom, and / or a sulfur atom) in its ring structure. Preferably, a 5-membered ring or a 6-membered ring heteroaryl group is mentioned. Specific examples of heteroaryl groups include 5-membered ring heteroaryl groups selected from pyrrolyl, furyl, thienyl, pyrazolyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, or thiadiazolyl groups; and 6-membered ring heteroaryl groups selected from pyridyl, pyridadinyl, pyrimidinyl, or pyrazinyl groups. Preferably, a triazolyl, oxadiazolyl, thiadiazolyl, pyrimidinyl, or pyrazinyl group is mentioned. Furthermore, examples of substituents on the heteroaryl group include a hydroxyl group, a halogen atom, a nitro group, a cyano group, and C which may be substituted with one or more substituents. １－６ C, which may be substituted with alkyl groups or one or more substituents. ２－６C may be substituted with one or more substituents, including an alkenyl group. ２－６ Alkynyl group, C １－６ Alkoxy group, aryloxy group, amino group, one or more C １－３ Examples include one or more (preferably one to three) identical or different groups selected from the group consisting of amino groups which may be substituted with alkyl groups and aryl groups, and preferably C which may be substituted with one or more substituents. １－６ alkyl group, one or more C １－３ Examples include amino groups which may be substituted with alkyl groups, and halogen atoms, more preferably trifluoromethyl groups, dimethylamino groups, and chloro atoms, but groups which are not affected by the oligomerization reaction conditions are preferred. Specific examples of heteroaryl groups which may be substituted with one or more substituents include 1,2,4-triazolyl group, 1,5-dimethyl-1,2,4-triazolyl group, 1,2,4-oxadiazolyl group, 5-methyl-1,2,4-oxadiazole-3-yl group, 1,2,4-thiadiazolyl group, 3-methyl-1,2,4-thiadiazole-5-yl group, 1,3-pyrimidinyl group, 1,5-pyrimidinyl group, 4-trifluoromethyl-1,5-pyrimidinyl group, 4-dimethylamino-2,4-pyrimidinyl group, 3-dimethylamino-2,4-pyrimidinyl group, 3-chloro-1,5-pyrimidinyl group, and 1,4-pyridazinyl group. Preferably, the groups include 1,5-dimethyl-1,2,4-triazole-3-yl group, 1,2,4-oxadiazolyl group, 3-methyl-1,2,4-thiadiazole-5-yl group, 1,5-pyrimidinyl group, 4-trifluoromethyl-1,5-pyrimidinyl group, 4-dimethylamino-2,4-pyrimidinyl group, 3-dimethylamino-2,4-pyrimidinyl group, 3-chloro-1,5-pyrimidinyl group, and 1,4-pyridazinyl group. More preferably, the groups include 1,5-dimethyl-1,2,4-triazole-3-yl group, 1,2,4-oxadiazol-3-yl group, and 3-methyl-1,2,4-thiadiazole-5-yl group.

[0020] In this specification, the term "a five- or six-membered ring heteroaryl group comprising one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents" refers to a five- or six-membered ring heteroaryl, which may be substituted with one or more substituents, as defined in the term "heteroaryl group".

[0021] In this specification, the term "heteroaryl group of a five or six-membered ring containing two or three heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents" means the triazolyl group, oxadiazolyl group, thiadiazolyl group, pyrimidinyl group, and pyridadinyl group, etc., which may be substituted with one or more substituents, as defined in the term "heteroaryl group".

[0022] In this specification, the term "C which may be substituted with one or more substituents" is used. １－６ "A sulfonyl group substituted with one substituent selected from the group consisting of alkyl groups and aromatic groups which may be substituted with one or more substituents" means a sulfonyl (S(O)) group substituted with such one substituent. ２ ) This means a C group. It may be substituted with one or more substituents. １－６ Aromatic groups, which may be substituted with alkyl groups or one or more substituents, are as defined above. Specific examples of substituents include methyl groups, trifluoromethyl groups, phenyl groups, and 4-methylphenyl groups, with methyl groups and phenyl groups being preferred.

[0023] In this specification, the term "C １－６ An "alkoxy group" is C １－６ This refers to a monovalent group in which an alkyl group is bonded to an oxygen atom, C １－６ This refers to an alkyl-O group. Specific examples include, but are not limited to, a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, a t-butoxy group, an s-butoxy group, and a 3-methylbutoxy group.

[0024] In this specification, the term "aryloxy group" refers to a monovalent group in which an aryl is bonded to an oxygen atom. Specific examples include, but are not limited to, a phenoxy group, a p - tolyloxy group, and the like.

[0025] In this specification, the term "one or more C" １－３ "amino group optionally substituted with an alkyl group" refers to an amino group in which one or more hydrogen atoms on the amino group may be substituted with a C1 - 3 alkyl group. Specific examples include, but are not limited to, methylamino, ethylamino, isopropylamino, dimethylamino, diethylamino, methylethylamino, and the like.

[0026] In this specification, examples of the term "halogen (atom)" include, for example, a fluorine atom (fluoro), a chlorine atom (chloro), a bromine atom (bromo), or an iodine atom (iodo), with a fluorine atom or a chlorine atom being preferred.

[0027] In this specification, when the compounds of the present invention, intermediate compounds, starting compounds, etc. have functional groups (e.g., a hydroxyl group, an amino group, a carboxyl group, etc.), according to the methods described in Theodora W. Greene, Peter G. M. Wuts, "Protective Groups in Organic Synthesis" 4th. ed., John Wiley & Sons, Inc., 1999, they are protected with protecting groups commonly used in organic synthetic chemistry, and after the reaction, the target compound can be obtained by removing the protecting groups. Examples of the protecting groups include those commonly used in organic synthetic chemistry described in the above - mentioned book. The protecting groups for each functional group are described below.

[0028] In this specification, the term "protecting group" as used within the sections on "hydroxyl group protecting group," "amino group protecting group," "phosphate group protecting group," and "mercapto group protecting group" is not particularly limited, as long as it can stably protect an amino group, hydroxyl group, phosphate group, or mercapto group during nucleic acid synthesis. Specifically, it refers to a protecting group that is stable under acidic or neutral conditions and can be cleaved by chemical methods such as hydrolysis, hydrolysis, electrolysis, and photolysis. Examples of such protecting groups include C1-C6 alkyl groups; C2-C6 alkenyl groups; C2-C6 alkynyl groups; acyl groups; tetrahydropyranyl or tetrahydrothiopyranyl groups; tetrahydrofuranyl or tetrahydrothiofuranyl groups; silyl groups; methyl groups substituted with C1-C6 alkoxy groups; methyl groups substituted with C1-C6 alkoxy groups; methyl groups substituted with halogen atoms; ethyl groups substituted with C1-C6 alkoxy groups; ethyl groups substituted with halogen atoms; methyl groups substituted with 1-3 aryl groups; C1-C6 alkyl groups, carbon Examples include alkenyl groups having 2 to 6 carbon atoms, alkynyl groups having 2 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, methyl groups substituted with 1 to 3 aryl groups substituted with a halogen atom and / or a cyano group; carbonyl groups substituted with alkoxy groups having 1 to 6 carbon atoms; aryl groups substituted with a halogen atom, alkoxy groups having 1 to 6 carbon atoms and / or a nitro group; carbonyl groups substituted with alkoxy groups having 1 to 6 carbon atoms and / or a silyl group substituted with three alkyl groups having 1 to 6 carbon atoms; alkenyloxycarbonyl groups; and aralkyloxycarbonyl groups which may be substituted with aryl groups substituted with alkoxy groups having 1 to 6 carbon atoms and / or a nitro group.

[0029] The term "protecting group for a hydroxyl group" refers to a protecting group commonly used in organic synthetic chemistry (especially nucleic acid synthesis), for example, an aliphatic acyl group; an aromatic acyl group; an optionally substituted aminocarbonyl group; an optionally substituted alkoxycarbonyl group; an aliphatic sulfonyl group; an aromatic sulfonyl group; a methyl group substituted with 1 to 3 aryl groups; a methyl group substituted with 1 to 3 aryl groups substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom and / or a cyano group; or a silyl group. Specific examples include benzyl (Bn), 4,4'-dimethoxytrityl (DMTr), 4-methoxytrityl, triphenylmethyl, 2-naphthylmethyl, diphenylaminocarbonyl (DPC), cyanoethoxycarbonyl, tetrahydropyranyl, trimethylsilyl, triethylsilyl, triisopropylsilyl, t-butyldimethylsilyl, t-butyldiphenylsilyl, triphenylsilyl, 4-methoxybenzyl (p-methoxybenzyl), 3,4-dimethoxybenzyl, 2,6-dimethoxybenzyl, p-phenylbenzyl, methanesulfonyl, trifluoromethanesulfonyl, methoxymethyl, benzoyl (Bz), phenoxyacetyl, or acetyl, etc., but are not limited thereto. For example, benzyl (Bn), 4,4'-dimethoxytrityl (DMTr), t-butyldimethylsilyl, t-butyldiphenylsilyl, trimethylsilyl (TMS), diphenylaminocarbonyl (DPC), methanesulfonyl, trifluoromethanesulfonyl are preferred, and 4,4'-dimethoxytrityl (DMTr) is more preferred.

[0030] In the present specification, the term "optionally substituted phosphate group" includes phosphoric acid, phosphorous acid, or hypophosphorous acid which may have a substituent (this includes a protecting group). For example, it includes a phosphate group represented by the formula -P(R Ｐ１ )R Ｐ２ , wherein, R Ｐ１ and R Ｐ２Each of these independently represents a hydroxyl group, a hydroxyl group protected by a nucleic acid synthesis protecting group, a mercapto group, a mercapto group protected by a nucleic acid synthesis protecting group, an amino group, an alkoxy group having 1 to 5 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, a cyanoalkoxy group having 1 to 6 carbon atoms, or an amino group substituted with an alkyl group having 1 to 6 carbon atoms. Here, in the above formula, R Ｐ１ OR Ｐ１ａ And R Ｐ２ NR Ｐ２ａ A group that can be represented as such is called a "phosphoamidite group" and is a preferred example. Ｐ１ａ These are alkyl groups having 1 to 5 carbon atoms, and cyanoalkyl groups having 1 to 6 carbon atoms, and R Ｐ２ａ This refers to an alkyl group having 1 to 6 carbon atoms, and a specific example of a "phosphoramidite group" is the one with the formula -P(O(CH) ２ ) ２ CN)(N(iPr) ２ A group represented by the formula -P(OCH) ３ ) (N(iPr) ２ Examples include, but are not limited to, the group represented by formula -P(O(CH). ２ ) ２ CN)(N(iPr) ２ A group represented by ) is preferred. Here, iPr represents an isopropyl group.

[0031] In this specification, the term "substitutable phosphate group" may form a phosphorus-containing chiral auxiliary. Specific examples of phosphorus-containing chiral auxiliary groups include, but are not limited to, the optically active bicyclic oxazaphosphoridine described in Non-Patent Literature N. Oka et al., J. AM. CHEM. SOC. 2008, 130, 16031, and the optically active 2-thio-1,3,2-oxatiaphosphorane containing a pentavalent phosphorus atom described in Non-Patent Literature KW Knouse et al., Science 10.1126 / science.aau3369 (2018).

[0032] "Protecting groups for amino groups" refers to protecting groups commonly used in organic synthesis (especially nucleic acid synthesis), such as aliphatic acyl groups; aromatic acyl groups; alkoxycarbonyl groups which may be substituted; methyl groups substituted with one to three aryl groups; and methyl groups substituted with one to three aryl groups which are substituted with a halogen atom and / or a cyano group. Specific examples include, but are not limited to, acetyl (Ac), phenoxyacetyl (Pac), t-butylphenoxyacetyl (Tac), p-isopropylphenoxyacetyl (iPr-Pac), trifluoroacetyl, propionyl, isobutyryl, benzoyl (Bz), methoxycarbonyl, ethoxycarbonyl, t-butoxycarbonyl (Boc), trimethylsilylethoxycarbonyl (Teoc), cyanoethoxycarbonyl (Ceoc), benzyloxycarbonyl (Cbz), allyloxycarbonyl, 9-fluorenylmethoxycarbonyl (Fmoc), dimethylaminomethylenyl, 2,2,2-trichloroethoxycarbonyl, t-amyloxycarbonyl, 4-methoxybenzyl, triphenylmethyl, 2-nitrobenzenesulfonyl, 2,4-dinitrobenzenesulfonyl, or 2-(trimethylsilyl)ethoxymethyl. For example, isobutyryl, benzoyl (Bz), t-butoxycarbonyl (Boc), and trimethylsilylethoxycarbonyl (Teoc) are preferred.

[0033] "Phosphate protecting groups" refer to protecting groups commonly used in organic synthesis (especially nucleic acid synthesis), and include, but are not limited to, C1-C6 alkyl groups substituted with C1-C6 alkyl groups and / or cyano groups; aralkyl groups; aralkyl groups substituted with aryl groups substituted with nitro groups and / or halogen atoms; aryl groups substituted with C1-C6 alkyl groups, halogen atoms, or nitro groups; 2-cyanoethyl groups; 2,2,2-trichloroethyl groups; benzyl groups; 2-chlorophenyl groups; or 4-chlorophenyl groups.

[0034] "Mercapto group protecting groups" refer to protecting groups commonly used in organic synthesis (especially nucleic acid synthesis), and include, but are not limited to, aliphatic acyl groups, aromatic acyl groups, and benzoyl groups (Bz).

[0035] In this specification, the term "leaving group" refers to a portion of the substrate molecule that has an electron pair and is cleaved by heterolysis during a reaction, and includes, for example, halogen atoms (e.g., fluorine, chlorine, bromine, iodine) and "hydroxyl leaving groups." Examples of hydroxyl leaving groups include sulfonyloxy groups (e.g., p-toluenesulfonyloxy, mesyloxy, trifluoromethanesulfonyloxy, etc.) and acyloxy groups (preferably saturated or unsaturated acyloxy groups having 1 to 8 carbon atoms, for example, R Ｌ It is expressed as -C(=O)-O-, and in the formula R ＬThe groups represented by these include aryl groups (preferably with a total of 6 to 8 carbon atoms, e.g., phenyl group, p-tolyl group), which may be substituted with an alkyl group (preferably with a total of 6 to 8 carbon atoms, e.g., phenoxy group, p-tolyloxy aralkyl groups (preferably with a total of 7 to 9 carbon atoms, e.g., benzyl group), arylalkenyl groups (preferably with a total of 8 or 9 carbon atoms, e.g., cinnamyl group), aralkyloxy groups (with a total of 7 to 15 carbon atoms, e.g., benzyloxy group, 9-fluorenylmethyloxy group), and alkoxy groups (linear or branched alkoxy groups with 1 to 8 carbon atoms, e.g., methoxy, ethoxy, t-butoxy). Specific examples include iodine, bromo, chloro, fluoro, mesyloxy, methanesulfonyloxy, trifluoromethanesulfonyloxy, and ethanesulfonyloxy. Examples of preferred leaving groups include, but are not limited to, 2,2,2-trifluoroethanesulfonyloxy, propanesulfonyloxy, isopropanesulfonyloxy, butanesulfonyloxy, nonafluorobutanesulfonyloxy, heptafluoropropane-1-sulfonyloxy, pentanesulfonyloxy, pentafluoroethanesulfonyloxy, pentanesulfonyloxy, cyclopentanesulfonyloxy, hexanesulfonyloxy, cyclohexanesulfonyloxy, o-toluenesulfonyloxy, m-toluenesulfonyloxy, p-toluenesulfonyloxy, benzenesulfonyloxy, o-bromobenzenesulfonyloxy, m-bromobenzenesulfonyloxy, p-bromobenzenesulfonyloxy, o-nitrobenzenesulfonyloxy, m-nitrobenzenesulfonyloxy, and p-nitrobenzenesulfonyloxy.

[0036] In this specification, examples of the term "acyl group" include aliphatic acyl groups and aromatic acyl groups. Specifically, examples of aliphatic acyl groups include formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, pentanoyl group, pivaloyl group, valeryl group, isovaleryl group, octanoyl group, nonanoyl group, decanoyl group, 3-methylnonanoyl group, 8-methylnonanoyl group, 3-ethyloctanoyl group, 3,7-dimethyloctanoyl group, undecanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, pentadecanoyl group, hexadecanoyl group, 1-methylpentadecanoyl group, 14-methylpentadecanoyl group, 13,13-dimethyltetradecanoyl group, heptadecanoyl group, 15-methylhexadecanoyl group, octadecanoyl group, Examples include alkylcarbonyl groups such as 1-methylheptadecanoyl, nonadecanoyl, aicosanoyl, and henaicosanoyl; aryloxyalkylcarbonyl groups such as phenoxyacetyl (Pac); carboxylated alkylcarbonyl groups such as succinoyl, glutaloyl, and adipoyl; carbonyl groups substituted with halogen atoms and C1 to C6 alkyl groups such as chloroacetyl, dichloroacetyl, trichloroacetyl, and trifluoroacetyl; alkoxyalkylcarbonyl groups such as methoxyacetyl; and unsaturated alkylcarbonyl groups such as (E)-2-methyl-2-butenoyl.Examples of aromatic acyl groups include, but are not limited to, arylcarbonyl groups such as benzoyl, α-naphthoyl, and β-naphthoyl groups; halogenoarylcarbonyl groups such as 2-bromobenzoyl and 4-chlorobenzoyl groups; arylcarbonyl groups substituted with C1 to C6 alkyl groups such as 2,4,6-trimethylbenzoyl and 4-toluyl groups; arylcarbonyl groups substituted with C1 to C6 alkoxy groups such as 4-anissoyl groups; carboxylated arylcarbonyl groups such as 2-carboxybenzoyl, 3-carboxybenzoyl, and 4-carboxybenzoyl groups; nitrated arylcarbonyl groups such as 4-nitrobenzoyl and 2-nitrobenzoyl groups; carbonylated arylcarbonyl groups substituted with C1 to C6 alkoxy groups such as 2-(methoxycarbonyl)benzoyl groups; and arylated arylcarbonyl groups such as 4-phenylbenzoyl groups.

[0037] In this specification, the term "aralkyl group" refers to an alkyl group having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, and more preferably 1 to 3 carbon atoms, which is substituted with an aromatic hydrocarbon group (for example, a monocyclic, bicyclic, or tricyclic aromatic hydrocarbon group with 6 to 14 members). Specific examples include, but are not limited to, benzyl, phenethyl, 1-naphthylmethyl, and 2-naphthylmethyl.

[0038] In this specification, examples of the term "silyl group" include, but are not limited to, silyl groups substituted with C1 to C6 alkyl groups such as trimethylsilyl group, triethylsilyl group, isopropyldimethylsilyl group, t-butyldimethylsilyl group, methyldiisopropylsilyl group, methyldi-t-butylsilyl group, and triisopropylsilyl group; silyl groups substituted with three C1 to C6 alkyl groups substituted with one or two aryl groups such as t-butyldiphenylsilyl group, diphenylmethylsilyl group, butyldiphenylbutylsilyl group, diphenylisopropylsilyl group, and phenyldiisopropylsilyl group; and triphenylsilyl group.

[0039] In this specification, the term "β-form" refers to a compound having a stereochemistry in which the direction of substitution of the nucleic acid base portion substituted at the 1' position of the ribose moiety and the direction of substitution of the 5' side chain substituted at the 4' position of the nucleic acid ribose are the same. In the case of cross-linked artificial nucleic acid 2',4'-LNA, it refers to a compound having a stereochemistry in which the direction of substitution of the nucleic acid base portion substituted at the 1' position of the ribose moiety and the direction of substitution of the 5' side chain substituted at the 4' position of the nucleic acid ribose, which is not used for cross-linking, are the same.

[0040] In this specification, the term "β-selective" means that the β-isomer can be selectively obtained.

[0041] In this specification, the term "base moiety of a nucleic acid, which may be substituted with one or more substituents" includes both natural and unnatural nucleic acid base moieties, and includes aromatic heterocyclic groups, such as monocyclic, dicyclic, and tricyclic groups. It should be obvious to those skilled in the art that various nucleic acid base moieties previously considered "unnatural" have subsequently been found in nature. Therefore, "nucleic acid base" includes not only known purine and pyrimidine heterocycles, but also their heterocyclic analogs and tautomers. Specific examples of nucleic acid base moieties include adenine, guanine, thymine, cytosine, uracil, purine, xanthine, diaminopurine, and 8-oxo-N. ６ - Methyladenine, 7-deazaxanthin, 7-deazaguanine, N ４ , N ４ - Ethanocytosine, N ６ , N ６ -Ethano-2,6-diaminopurine, 5-methylcytosine, 5-(C ３ ~C ６ )-Alkinylcytosine, 5-Fluorocytosine, 5-Bromouracil, Pseudoisocytosine, 2-Hydroxy-5-methyl-4-Triazolopyridine, Isocytosine, Isoguanine, Inosine, N ６ - Allylpurine, N ６ - Acylprin, N ６ - Benzylpurine, N ６ - HaroPrin, N ６- Vinyl pudding, N ６ - Acetylene purine, N ６ - Acylprin, N ６ - Hydroxyalkylpurine, N ６ - Thioalkylpurine, N ２ - Alkylpurine, N ４ - Alkylpyrimidine, N ４ - Acylpyrimidine, N ４ - Benzylpurine, N ４ - Halopyrimidine, N ４ - Vinylpyrimidine, N ４ - Acelenate pyrimidine, N ４ - Acetylpyrimidine, N ４ - Hydroxyalkylpyrimidine, N ６ - Thioalkylpyrimidine, 6-azapyrimidine, 6-azacytosine, 2- and / or 4-mercaptopyrimidine, uracil, C ５ - Alkylpyrimidine, C ５ - Benzylpyrimidine, C ５ - Halopyrimidine, C ５ - Vinylpyrimidine, C ５ - Acetylene pyrimidine, C ５ - Acylpyrimidine, C ５ - Hydroxyalkylpurine, C ５ - Amidopyrimidine, C ５ -Cyanopyrimidine, C ５ - Nitropyrimidine, C ５ - Aminopyrimidine, N ２ - Alkylpurine, N ２Examples of nucleic acid base moieties include, but are not limited to, alkyl-6-thiopurine, 5-cytidinyl, 5-azaurasilyl, trazolopyridinyl, imidazolopyridinyl, pyrrolopyridinyl, and pyrazolopyridinyl. Preferred nucleic acid base moieties include, for example, adenine, guanine, 2,6-diaminopurine, thymine, 2-thiothymine, cytosine, 5-methylcytosine, uracil, 5-fluorocytosine, xanthine, 6-aminopurine, 2-aminopurine, 6-chloro-2-aminopurine, and 6-chloropurine, and particularly preferred nucleic acid base moieties include, for example, adenine, guanine, cytosine, 5-methylcytosine, thymine, or uracil. These nucleic acid base moieties may be substituted with one or more substituents, such as a hydroxyl group, C １－６ alkoxy group, mercapto group, C １－６ alkylthio group, amino group, C １－６ an amino group substituted with an alkyl group, C １－６ alkyl group, C １－６ Examples include alkynyl groups, oxo groups, thioxo groups, and halogen atoms. Functional oxygen, sulfur, and nitrogen groups on the base moiety may be protected and / or deprotected if necessary or desired. Suitable protecting groups are well known to those skilled in the art and include, but are not limited to, the hydroxyl group protecting groups and amino group protecting groups mentioned above, such as diphenylaminocarbonyl group, silyl group (e.g., trimethylsilyl group, dimethylhexylsilyl group, t-butyldimethylsilyl group, and t-butyldiphenylsilyl group), trityl group, alkyl group, acyl group (e.g., acetyl group, propionyl group, isobutyryl group, benzoyl group (Bz), phenoxyacetyl group (Pac)), alkoxycarbonyl group (e.g., t-butoxycarbonyl group (Boc), benzyloxycarbonyl group (Cbz), diphenylaminocarbonyl group (DPC), cyanoethoxycarbonyl group (Ceoc)), sulfonyl group (e.g., methanesulfonyl group, and p-toluenesulfonyl group), and dimethylaminomethyleneyl group.

[0042] In this specification, the term "artificial nucleic acid" includes artificial nucleosides, artificial nucleotides (wherein a single nucleoside or nucleotide may also be referred to as a monomer), or artificial oligonucleotides. These artificial nucleic acids are not natural nucleic acids and can only be produced artificially. These artificial nucleic acids include those in which the nucleic acid base portion has a non-natural base, those in which the sugar portion has a modified sugar, and / or those in which the phosphate portion has a non-natural phosphate group. In this invention, however, the term refers to those in which the sugar portion has a non-natural sugar, particularly those having (deoxy)ribose with the carbon atoms at the 2' and 4' positions cross-linked.

[0043] In this specification, the term "artificial oligonucleotide" refers to a compound in which two or more identical or different "artificial nucleotides" are linked together by a phosphate diester bond, a thiophosphate diester bond, or the like, preferably containing 2 to 100 artificial nucleotides, more preferably 5 to 50 artificial nucleotides, and most preferably 10 to 30 artificial nucleotides, or a compound in which these artificial nucleotides form a double helix with a complementary chain. In this specification, an oligonucleotide in which two or more nucleotides are linked together may also be referred to as an oligomer.

[0044] This document describes embodiments of the compound of the present invention.

[0045] Compound represented by general formula I According to one embodiment, General formula (I): [In the formula, B is the base portion of a nucleic acid which may be substituted with one or more substituents; R １ , R ２ , R ３ and R ４ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ It is an alkyl group; R ５ and R ６ Each of these is independently a hydrogen atom, a hydroxyl protecting group, or an optionally substituted phosphate group; m is 1 or 2; and X is the following formula (II-1), (II-2), or (II-3): The base is represented by; the symbol in formula (II-1), (II-2), or (II-3): R indicates a bond site with the 2'-amino group; ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ C, which may be substituted with alkyl groups or one or more substituents. ２－６ C may be substituted with one or more substituents, such as an alkenyl group. ２－６ A is an alkynyl group or an aromatic group which may be substituted with one or more substituents; A is an aromatic group; M is a C which may be substituted with one or more substituents. １－６ The compound represented by [ ], or a salt thereof, is provided.

[0046] In one embodiment, a compound represented by general formula (I) or a salt thereof is general formula I-a: Preferably, the compound is represented by the formula or a salt thereof (wherein R １ , R ２ , R ３ , R ４ , R ５ , R ６ , B, X, and m are equivalent to those in general formula (I).

[0047] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein ring B in formula (I) may have one or more protecting groups: adeninyl, guaninyl, cytosinyl, 5-methylcytosinyl, or urasilyl.

[0048] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein ring B in formula (I) is a 5-methylcytosinyl group which may have one or more protecting groups, or a 5-urasilyl group which may have one or more protecting groups.

[0049] In one embodiment, in formula (I), R １ , R ２ , R ３ and R４ The present invention provides a compound represented by formula (I) or a salt thereof, wherein each of the elements is independently a hydrogen atom and m is 1.

[0050] In one embodiment, in formula (I), R ６ is a hydrogen atom or a DMTr group, and R ５ is a hydrogen atom or -P(O(CH) ２ ) ２ CN) (N(iPr) ２ The present invention provides a compound represented by formula (I) or a salt thereof.

[0051] In one embodiment, in formula (I), R ６ is a DMTr group, and R ５ ga-P(O(CH) ２ ) ２ CN) (N(iPr) ２ The present invention provides a compound represented by formula (I) or a salt thereof.

[0052] The embodiments used can be broadly classified into those described as formulas (II-1), (II-2), or (II-3). First, we can list compounds in which X in formula (I) is the group shown in formula (II-1) (hereinafter referred to as "urea-type compounds" in this specification).

[0053] In one embodiment, X is a base represented by formula (II-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ The present invention provides a compound represented by formula (I) or a salt thereof, wherein the compound is an alkyl group or an aromatic group which may be substituted with one or more substituents.

[0054] In one embodiment, X is a base represented by formula (II-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－３ The present invention provides a compound represented by formula (I) or a salt thereof, wherein the compound is an alkyl group or an aromatic group which may be substituted with one or more substituents.

[0055] In one embodiment, X is a base represented by formula (II-1); and R ７ and R ８ The present invention provides a compound represented by formula (I) or a salt thereof, wherein each of the elements is independently a hydrogen atom, a methyl group, an isopropyl group, or a phenyl group.

[0056] In one embodiment, X is a base represented by formula (II-1); and R ７ and R ８ The combination is R ７ and R ８ A combination where both are hydrogen atoms, R ７ and R ８ A combination where both are methyl groups, R ７ is a hydrogen atom and R ８ A combination in which R is a methyl group. ７ is a hydrogen atom and R ８ A combination in which is an isopropyl group, or R ７ is a hydrogen atom and R ８ The present invention provides a compound represented by formula (I) or a salt thereof, in which the combination is a phenyl group.

[0057] In one embodiment, X is a base represented by formula (II-1); and R ７ and R ８ The combination is R ７ and R ８ A combination where both are hydrogen atoms, R ７ and R ８ A combination where both are methyl groups, R ７ and R ８ A combination in which one is a hydrogen atom and the other is a methyl group, R ７ and R ８ A combination in which one is a hydrogen atom and the other is an isopropyl group, or R ７ and R ８ The present invention provides a compound represented by formula (I) or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is a phenyl group.

[0058] In one embodiment, X is a base represented by formula (II-1); and R７ and R ８ A compound represented by formula (I) or a salt thereof, wherein one of them is a hydrogen atom and the other is a methyl group.

[0059] In one embodiment, X is a group represented by formula (II-1); and R ７ and R ８ A compound represented by formula (I) or a salt thereof, wherein one of them is a hydrogen atom and the other is an isopropyl group.

[0060] Further, a compound in which X in formula (I) is a group represented by formula (II-2) (hereinafter, may also be referred to as "heteroaryl-type compound" in the present specification) can be mentioned.

[0061] In one embodiment, X is a group represented by formula (II-2); and A is a 5- or 6-membered heteroaryl group containing one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom, which may be substituted with one or more substituents. A compound represented by formula (I) or a salt thereof is provided.

[0062] In one embodiment, X is a group represented by formula (II-2); and A is a 5- or 6-membered heteroaryl group containing two or three heteroatoms including at least two nitrogen atoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom, which may be substituted with one or more substituents. A compound represented by formula (I) or a salt thereof is provided.

[0063] In one embodiment, X is a group represented by formula (II-2); and A is a 5- or 6-membered heteroaryl group containing one or more heteroatoms including at least two nitrogen atoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom, which may be substituted with one or more substituents, and the substituents are each independently a C １－３ alkyl group which may be substituted with one or more halogen atoms, a halogen atom, and an amino group which may be substituted with one or more C １－３ alkyl groups. A compound represented by formula (I) or a salt thereof is provided.

[0064] In one embodiment, X is a group represented by formula (II-2); and A is a 5 or 6-membered heteroaryl group containing one or more heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents, and each substituent may independently be substituted with one or more halogen atoms. １－３ Alkyl alkyl groups, halogen atoms, and one or more C atoms １－３ The present invention provides a compound represented by formula (I) or a salt thereof, selected from the group consisting of amino groups which may be substituted with alkyl groups.

[0065] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-2), and A is a five- or six-membered ring heteroaryl group selected from the group consisting of a triazolyl group, an oxadiazolyl group, a thiadiazolyl group, a pyrimidinyl group, and a pyrazinyl group, which may be substituted with one or more substituents.

[0066] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-2), and the triazolyl group, which may be substituted with one or more substituents as A, is a 1,5-dimethyl-1,2,4-triazol-3-yl group.

[0067] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-2), and the oxadiazolyl group, which may be substituted with one or more substituents as A, is a 5-methyl-1,2,4-oxadiazole-3-yl group.

[0068] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-2), and the thiadiazolyl group, which may be substituted with one or more substituents as A, is a 3-methyl-1,2,4-thiadiazole-5-yl group.

[0069] In one embodiment, X is a group represented by formula (II-3); and M is C which may be substituted with one or more substituents. １－６ The present invention provides a compound represented by formula (I) or a salt thereof, which is a sulfonyl group substituted with one substituent selected from the group consisting of alkyl groups and aryl groups which may be substituted with one or more substituents.

[0070] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-3); and M is a sulfonyl group substituted with one substituent selected from the group consisting of a methyl group which may be substituted with one or more substituents, and a phenyl group which may be substituted with one or more substituents.

[0071] In one embodiment, the present invention provides a compound represented by formula (I) or a salt thereof, wherein X is a group represented by formula (II-3); and M is a sulfonyl group substituted with one substituent selected from the group consisting of methyl and phenyl groups.

[0072] In one embodiment, as a specific example of a compound represented by formula (I) or a salt thereof, one or more compounds selected from the group consisting of the following compounds are provided, or a salt thereof. The following compounds: 3-[[(1R,4R,6R,7S)-4-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-6-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-methylsulfonyl-5-oxa-2-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 1 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 2 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate (Compound 3 of the present invention); N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (Compound 4 of the present invention); 3-[[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopronylamino)phosphanyl]oxypropanenitrile (Compound 5 of the present invention);N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl)oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 6 of the present invention); (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 7 of the present invention); (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 8 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(methylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (compound 9 of the present invention); (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 10 of the present invention);(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 11 of the present invention); (1R,3R,4R,7S)-3-(4-benzamide-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 12 of the present invention); [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(isopropylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (compound 13 of the present invention); (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 14 of the present invention); (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 15 of the present invention);(1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (compound 16 of the present invention); 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 17 of the present invention); 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 18 of the present invention); N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-6-formamidine (compound 19 of the present invention); N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (compound 20 of the present invention);3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 21 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 22 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 23 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanethoxy-(diisopropylamino)phosphanyl]oxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 24 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 25 of the present invention);N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-4-yl]benzamide (Compound 26 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamine)phosphanyl]oxypropanenitrile (Compound 27 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanothoxy-(diisopropylamino)phosphanyl]oxy-5-[(6-dimethylamino)pyrimidine-4-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 28 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)oxypropanenitrile (compound 29 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 30 of the present invention);3-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 31 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 32 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 33 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 34 of the present invention); N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-formamidine (compound 35 of the present invention);N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (compound 36 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 37 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 38 of the present invention); 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (compound 39 of the present invention); N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (compound 40 of the present invention);N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]dihydropyrimidine-2-one (compound 41 of the present invention); N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethylformamidine (compound 42 of the present invention); A compound selected from the group consisting of N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide (compound 43 of the present invention); and N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide (compound 44 of the present invention).

[0073] A compound represented by the general formula (I') of an oligonucleotide. According to one embodiment, general formula (I'): [In the formula, B is the base portion of a nucleic acid which may be substituted with one or more substituents; R １ , R ２ , R ３ and R ４ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ It is an alkyl group; m is 1 or 2; and X is the following formula (II'-1), (II'-2), or (II'-3): The base is represented by; the symbols listed in formula (II'-1), (II'-2), or (II'-3): indicates a bond site with a 2'-amino group; A is an aromatic group containing one or more heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms, which may be substituted with one or more substituents; M is a C which may be substituted with one or more substituents. １－６ The present invention provides oligonucleotides or salts thereof having one or more nucleosides represented by [ ], which are sulfonyl groups substituted with one substituent selected from the group consisting of alkyl groups and aromatic groups that may be substituted with one or more substituents.

[0074] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein ring B in formula (I') may have one or more protecting groups: adeninyl, guaninyl, cytosinyl, 5-methylcytosinyl, or urasilyl.

[0075] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein ring B in formula (I') is a 5-methylcytosinyl group which may have one or more protecting groups, or a 5-urasilyl group which may have one or more protecting groups.

[0076] In one embodiment, in formula (I'), R １ , R ２ , R ３ and R ４ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein each of the elements is independently a hydrogen atom and m is 1.

[0077] In one embodiment, a sulfurized oligonucleotide compound represented by formula (I') or a salt thereof is provided, wherein at least one of the nucleotides in formula (I') is linked by a phosphorothioate bond.

[0078] Examples of compounds in which X in formula (I') is the group shown in formula (II'-1) (hereinafter sometimes referred to as "urea-type compounds" in this specification) are given.

[0079] In one embodiment, in formula (I'), X is the base represented by formula (II'-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ The aromatic group is an alkyl group or may be substituted with one or more substituents. The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof.

[0080] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－６ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein the oligonucleotide compound is an alkyl group or an aromatic group which may be substituted with one or more substituents.

[0081] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ Each of these C atoms may be independently substituted with a hydrogen atom or one or more substituents. １－３ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein the oligonucleotide compound is an alkyl group or an aromatic group which may be substituted with one or more substituents.

[0082] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein each of the elements is independently a hydrogen atom, a methyl group, an isopropyl group, or a phenyl group.

[0083] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ The combination is R ７and R ８ A combination where both are hydrogen atoms, R ７ and R ８ A combination where both are methyl groups, R ７ is a hydrogen atom and R ８ A combination in which R is a methyl group. ７ is a hydrogen atom and R ８ A combination in which is an isopropyl group, or R ７ is a hydrogen atom and R ８ The present invention provides oligonucleotide compounds represented by formula (I') or salts thereof, in which the combination is a phenyl group.

[0084] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ The combination is R ７ and R ８ A combination where both are hydrogen atoms, R ７ and R ８ A combination where both are methyl groups, R ７ and R ８ A combination in which one is a hydrogen atom and the other is a methyl group, R ７ and R ８ A combination in which one is a hydrogen atom and the other is an isopropyl group, or R ７ and R ８ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is a phenyl group.

[0085] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is a methyl group.

[0086] In one embodiment, X is a base represented by formula (II'-1); and R ７ and R ８The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein one of the atoms is a hydrogen atom and the other is an isopropyl group.

[0087] Furthermore, examples include compounds in which X in formula (I') is the group shown in formula (II'-2) (hereinafter referred to as "heteroaryl compounds" in this specification).

[0088] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2), and A is a five- or six-membered heteroaryl group comprising one or more heteroatoms selected from the group consisting of nitrogen, oxygen, and sulfur atoms, which may be substituted with one or more substituents.

[0089] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2); and A is a 5 or 6-membered heteroaryl group comprising two or three heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents.

[0090] In one embodiment, X is a group represented by formula (II'-2); and A is a 5 or 6-membered heteroaryl group containing one or more heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents, and each substituent may independently be substituted with one or more halogen atoms. １－３ Alkyl alkyl groups, halogen atoms, and one or more C atoms １－３ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, selected from the group consisting of amino groups which may be substituted with alkyl groups.

[0091] In one embodiment, X is a group represented by formula (II'-2); and A is a 5 or 6-membered heteroaryl group containing one or more heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents, and each substituent may independently be substituted with one or more halogen atoms. １－３ Alkyl alkyl groups, halogen atoms, and one or more C atoms １－３ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, selected from the group consisting of amino groups which may be substituted with alkyl groups.

[0092] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2), and the 5- or 6-membered ring heteroaryl group as A is selected from the group consisting of a triazolyl group, an oxadiazolyl group, a thiadiazolyl group, a pyrimidinyl group, and a pyrazinyl group, and may be substituted with one or more substituents.

[0093] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2), and the triazole group A, which may be substituted with one or more substituents, is a 1,5-dimethyl-1,2,4-triazole-3-yl group.

[0094] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2), and the oxadiazolyl group, which may be substituted with one or more substituents as A, is a 5-methyl-1,2,4-oxadiazole-3-yl group.

[0095] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-2), and the thiadiazolyl group, which may be substituted with one or more substituents as A, is a 3-methyl-1,2,4-thiadiazole-5-yl group.

[0096] In one embodiment, X is a group represented by formula (II'-3); and M is C which may be substituted with one or more substituents. １－６ The present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein the sulfonyl group is substituted with one substituent selected from the group consisting of alkyl groups and aryl groups which may be substituted with one or more substituents.

[0097] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-3), and M is a sulfonyl group substituted with one substituent selected from the group consisting of a methyl group which may be substituted with one or more substituents, and a phenyl group which may be substituted with one or more substituents.

[0098] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-3), and M is a sulfonyl group substituted with one substituent selected from the group consisting of methyl and phenyl groups.

[0099] In one embodiment, the present invention provides an oligonucleotide compound represented by formula (I') or a salt thereof, wherein X is a group represented by formula (II'-3), and M is a sulfonyl group substituted with one substituent selected from the group consisting of methyl and phenyl groups.

[0100] In one embodiment, the oligonucleotide or its salt is formed by linking two or more such nucleotides, preferably containing 2 to 100 nucleotides, more preferably containing 5 to 50 nucleotides, and most preferably having 10 to 30 artificial nucleotides linked to it, or forming a double helix with complementary strands thereof.

[0101] In this specification, the term "salt of a compound" means alkali metal salts such as sodium salts, potassium salts, and lithium salts; alkaline earth metal salts such as calcium salts and magnesium salts; metal salts such as aluminum salts, iron salts, zinc salts, copper salts, nickel salts, and cobalt salts; inorganic salts such as ammonium salts; t-octylamine salts, dibenzylamine salts, morpholine salts, glucosamine salts, phenylglycine alkyl ester salts, ethylenediamine salts, N-methylglucamine salts, guanidine salts, diethylamine salts, triethylamine salts, hexylamine salts, dicyclohexylamine salts, N,N'-dibenzylethylenediamine salts, chloroprocaine salts, procaine salts, diethanolamine salts, N-benzylphenethylamine salts, piperazine salts, tetra Examples include, but are not limited to, amine salts such as organic salts like methylammonium salt and tris(hydroxymethyl)aminomethane salt; halogenated hydrochloride salts such as hydrofluoric acid, hydrochloride, hydrobromide, and hydroiodide; inorganic salts such as nitrates, perchlorates, sulfates, and phosphates; C1 to C6 alkanesulfonates such as methanesulfonate, trifluoromethanesulfonate, and ethanesulfonate; arylsulfonates such as benzenesulfonate and p-toluenesulfonate; organic salts such as acetate, malate, fumarate, succinate, citrate, tartrate, oxalate, and maleate; and amino acid salts such as glycine salt, lysine salt, arginine salt, ornithine salt, glutamate, and aspartate. It includes pharmacologically acceptable salts.

[0102] Each compound represented by general formula (I) described herein includes enantiomers, diastereomers, or mixtures thereof. For example, the stereochemistry of the sugar moiety in the structure of each compound includes α- and β-forms, but the β-form is preferred. When the compounds represented by general formula (I) are obtained in the form of diastereomers or enantiomers, they can be separated by conventional methods well known in the field of organic synthesis (e.g., sugar synthesis), such as chromatography or fractional crystallization. For example, the following formula: The compound represented by 2Td has a β-conjugation of the sugar moiety.

[0103] Each compound represented by general formula I described herein is an isotope (for example, ３ H, １３ C, １４ C, １５ N, １８ F, ３２ P, ３５ S, １２５ This includes compounds labeled with (I, etc.) and deuterium converters.

[0104] Oligonucleotides and their analogues described herein can be combined with excipients commonly used in the pharmaceutical formulation technology, such as excipients, binders, preservatives, oxidative stabilizers, disintegrants, lubricants, and flavoring agents, to form parenteral formulations or liposomal formulations. Furthermore, they can be combined with pharmaceutical carriers commonly used in the art to prepare topical formulations such as liquids, creams, and ointments.

[0105] (Manufacturing Method) The manufacturing method of the compounds of the present invention is described below. In addition, the optically active compound having an absolute configuration in each of the starting compounds and intermediate compounds described below can also be produced by using an optically active material as the starting material or by separating the isomer produced at an intermediate stage of synthesis. Furthermore, the nucleic acid base exchange reaction in which nucleic acid bases are substituted as described below allows for efficient β-selective transglycosylation, and the resulting compound represented by general formula I can selectively obtain the desired β-isomer.

[0106] The compounds of the present invention or their pharmaceutically acceptable salts may be produced by the following methods, but are not limited thereto. If the specific production methods for the raw materials are not described, commercially available raw materials may be used, or they may be produced by known methods or similar methods.

[0107] The abbreviations used in this specification have the following meanings: THF: Tetrahydrofuran DMSO: Dimethyl sulfoxide MsCl: Methanesulfonyl chloride DMAP: N,N-dimethyl-4-aminopyridine iPr ２NET and DIPEA: N,N-diisopropylethylamine BSA: N,O-bis(trimethylsilyl)acetamide TMSOTf: Trimethylsilyl trifluoromethanesulfonate TBSOTf: t-Butyldimethylsilyltrifluoromethanesulfonate Bn: Benzyl TMS: Trimethylsilyl TBDPS: tert-butyldiphenylsilyl Ac: Acetyl MOE: Methoxyethyl CH ２ Cl ２ : Dichloroethane MeCN: Acetonitrile DMTr: 4,4'-Dimethoxytrityl

[0108] First, we will outline the method for producing the compound (monomer) of the present invention.

[0109] (Sulfonamide Compounds) This section describes a method for producing the so-called sulfonamide compounds of the present invention, in which X in general formula I is the group represented by formula (II-3). A typical example of the production scheme is shown in reaction scheme 1 below, but is not limited to this. Reaction Scheme 1

[0110] (Step 1) Using starting compound 1, which is a sugar compound (for example, it can be produced according to the method described in International Publication No. 2017 / 047816), as a starting material, R in general formula (I) is prepared by a known method. ５Intermediate compound 2 is produced by introducing a hydroxyl protecting group as a base. Alternatively, intermediate compound 2 is produced by performing a nucleic acid base exchange reaction with another potentially protected nucleic acid base (represented by the abbreviation B') on the nucleic acid base portion (represented by the abbreviation B) of starting compound 1, while simultaneously introducing a hydroxyl protecting group. The introduction of this hydroxyl protecting group can be carried out under reaction conditions well known in organic synthesis chemistry (e.g., nucleic acid synthesis), depending on the type of protecting group. For example, if the hydroxyl protecting group is a silyl protecting group (e.g., TMS), a silylation agent (e.g., BSA, hexamethyldisilazane, TMS chloride) can be used. In this case, a Lewis acid (e.g., TMSOTf, TBSOTf, tin chloride) may be added. The silylation agent can be used in amounts of about 1 to about 20 molar equivalents relative to the reaction substrate, and the Lewis acid can be used in amounts of a catalytic amount (about 0.05 molar equivalents) to 2 molar equivalents. Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (for example, ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, and chloroform, hydrogen carbides such as benzene and toluene, acetonitrile, water, or a mixture thereof). The reaction proceeds preferably at temperatures from 0°C to high temperatures, particularly from room temperature to about 60°C.

[0111] Furthermore, through a nucleic acid base exchange reaction (transglycosyl reaction), the pyrimidine base portion of nucleic acid bases such as thymine (T) and uracil (U) can be replaced with another potentially protected nucleic acid base portion (for example, adenine (A), guanine (G), uracil (U), thymine (T), cytosine (C), or 5-methylcytosine ( Ｍｅ By substituting with C), an intermediate compound 2 in which the nucleic acid base portion has been exchanged can be produced. This base exchange reaction can be carried out in the presence of a Lewis acid (e.g., TMSOTf, TBSOTf), and the reaction can be accelerated by reacting with a silylating agent.

[0112] (Step 2) Next, intermediate compound 3 is produced by reacting intermediate compound 2 with an alkyl sulfonyl halide or aromatic sulfonyl halide using a known method, thereby sulfonamiding the imino nitrogen atom. Examples of sulfonamiding reagents used in the sulfonamiding reaction include alkynyl sulfonyl halide reagents (e.g., methanesulfonyl chloride (MsCl)), alkyl sulfonic acid anhydrides (e.g., methanesulfonic acid anhydride), aromatic sulfonyl halide reagents (e.g., benzenesulfonyl chloride), or aromatic sulfonic acid anhydrides (e.g., benzenesulfonic acid anhydride), and can be used in the presence of a base (e.g., triethylamine, DIPEA). The sulfonamiding reagent can be used in approximately equivalent moles to some excess equivalent moles (e.g., about 1.0 molar equivalent) relative to the reaction substrate. Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (such as ethers like THF, halogenated hydrocarbons like dichloromethane, dichloroethane, and chloroform, hydrogen carbides like benzene and toluene, acetonitrile, water, or a mixture thereof). The reaction proceeds preferably at temperatures from -25°C to room temperature, and particularly from 0°C to room temperature.

[0113] (Step 3) Next, intermediate compound 4 is produced by using intermediate compound 3 as a starting material and deprotecting the hydroxyl group protecting group introduced in Step 1 by a known method. This deprotection reaction can be carried out under appropriate reaction conditions (e.g., reagents, etc.) depending on the type of protecting group. For example, the hydroxyl group protecting group (abbreviation R ＰＲＯ When the protecting group is a silyl protecting group (e.g., TMS), the reaction can be carried out by hydrolysis under acidic conditions (e.g., acetic acid-THF-water) or by treatment with a fluoride ion donating reagent (e.g., TBAF). Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (e.g., ethers such as THF, halogenated hydrocarbons such as dichloromethane, water, or a mixture thereof). The reaction preferably proceeds at a temperature of -25°C to 100°C, particularly 0°C to 50°C.

[0114] (Step 4) Furthermore, intermediate compound 4 is used as a starting material and phosphoramidized under reaction conditions (e.g., reagents) that are generally known in organic synthesis (especially nucleic acid synthesis) to produce the desired sulfonamide compound of the present invention. Examples of phosphoramidizing reagents include the following formula: Examples include, but are not limited to, the phosphoramidite reaction. The phosphoramidite reaction may be carried out in the presence of a base (e.g., DIPEA) or an acid (e.g., diisopropylammonium tetrazolide, 4,5-dicyanoimidazole) as appropriate. The phosphoramidite reagent can be used in amounts of 1 to 10 molar equivalents, preferably 1 to 5 molar equivalents (e.g., 3 molar equivalents), relative to the reaction substrate. Any solvent that does not affect the reaction may be used, and the reaction can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, acetonitrile, or a mixture thereof). The reaction preferably proceeds at a temperature of -25°C to 60°C, particularly 0°C to room temperature.

[0115] Furthermore, at any stage before or after step 4, the substituents on the nucleic acid base ring may be modified as appropriate (for example, benzoylation or acetylation of the amino substituent of the cytosine ring).

[0116] Furthermore, any multiple steps (1) to (4) described above (for example, steps (1) and (2), and steps (2) and (3)) may be performed consecutively.

[0117] (Urea Compounds) This section describes a method for producing the so-called urea compounds of the present invention, in which X in general formula I is the group represented by formula (II-1). A typical example of the production scheme is shown in reaction scheme 2 below, but it is not limited to these. Reaction Scheme 2

[0118] (Step 1) Before carrying out the urea formation reaction using the starting compound 1 as a starting material by a known method, the nucleic acid base portion (represented by abbreviation B) in the starting compound 1 may be replaced with another protected nucleic acid base portion (represented by abbreviation B') in a nucleic acid base exchange reaction, similar to Step 1 of the reaction scheme 1, and then the urea formation reaction may be carried out. Alternatively, similar to the reaction scheme, a hydroxyl protecting group may be introduced as appropriate after this nucleic acid base exchange reaction. The nucleic acid base exchange reaction (transglycosyl reaction) is carried out by a known method in which the pyrimidine base portion of a nucleic acid base such as thymine (T) or uracil (U) is replaced with another protected nucleic acid base portion (for example, adenine (A), guanine (G), uracil (U), thymine (T), cytosine (C), or 5-methylcytosine ( Ｍｅ By substituting with C), an intermediate compound 5 in which the nucleic acid base portion has been exchanged can be produced. This base exchange reaction can be carried out in the presence of a Lewis acid (e.g., TMSOTf, TBSOTf), and the reaction can be accelerated by reacting with a silylating agent (e.g., BSA). Furthermore, the introduction of this hydroxyl group protecting group can be carried out under reaction conditions well known in organic synthesis chemistry (e.g., nucleic acid synthesis), depending on the type of protecting group. For example, if the hydroxyl group protecting group is a silyl protecting group (e.g., TMS), a silylating agent (e.g., BSA, hexamethyldisilazane, TMS chloride) can be used. In this case, a Lewis acid (e.g., TMSOTf, TBSOTf, tin chloride) may be added. The silylating agent can be used in amounts of about 1 to about 20 molar equivalents relative to the reaction substrate, and the Lewis acid can be used in amounts of a catalytic amount (about 0.05 molar equivalents) to 2 molar equivalents. Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (for example, ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, and chloroform, hydrogen carbides such as benzene and toluene, acetonitrile, water, or a mixture thereof). The reaction proceeds preferably at temperatures from 0°C to high temperatures, particularly from room temperature to about 60°C.

[0119] (Step 2) Next, using starting compound 1 or intermediate compound 5 as a starting material, the urea-forming reagent is reacted with starting compound 1 or intermediate compound 5 by a known method to urea-form on the imino nitrogen atom and produce intermediate compound 6. Examples of urea-forming reagents used in the urea-formation reaction include isocyanates, N-alkylcarbamoyl halide reagents (e.g., N-methylcarbamoyl chloride), or N,N-dialkylcarbamoyl halide reagents (e.g., N,N-dimethylcarbamoyl chloride), and can be used in or without the presence of a base (e.g., DIPEA). The urea-forming reagent can be used in approximately equivalent moles to some excess equivalent moles (e.g., about 1.0 molar equivalent) relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, or mixed solvents thereof). The reaction preferably proceeds at temperatures between -25°C and room temperature, particularly between 0°C and room temperature.

[0120] (Step 3) Next, if a hydroxyl protecting group was introduced in Step 1 as appropriate, intermediate compound 7 is produced by using intermediate compound 6 as a starting material and deprotecting the introduced hydroxyl protecting group by a known method. This deprotection reaction can be carried out under appropriate reaction conditions (e.g., reagents, etc.) depending on the type of protecting group, similar to Step 3 of Reaction Scheme 1. For example, a hydroxyl protecting group (abbreviated R ＰＲＯ When the protecting group is a silyl protecting group (e.g., TMS), the reaction can be carried out by hydrolysis under acidic conditions (e.g., acetic acid-THF-water) or by treatment with a fluoride ion donating reagent (e.g., TBAF). Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (e.g., ethers such as THF, halogenated hydrocarbons such as dichloromethane, water, or a mixture thereof). The reaction preferably proceeds at a temperature of -25°C to 100°C, particularly 0°C to 50°C.

[0121] (Step 4) Furthermore, similar to Step 4 of Reaction Scheme 1, intermediate compound 6 or intermediate compound 7 is used as a starting material and phosphoramidized by a known method to produce the desired urea series (e.g., methylurea series and isopropylurea series) compounds of the present invention. Examples of phosphoramidizing reagents include 2-cyanoethyl-N,N-diisopropylchlorophosphoramidite, which can be used in the presence of a base (e.g., triethylamine, DIPEA). The phosphoramidizing reagent can be used in amounts of 1 to 10 molar equivalents, preferably 1 to 5 molar equivalents (e.g., 3 molar equivalents), relative to the reaction substrate. Any solvent that does not affect the reaction can be used, and the procedure can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, acetonitrile, or a mixture thereof). The reaction proceeds preferably at temperatures between -25°C and 60°C, particularly between 0°C and room temperature.

[0122] Furthermore, any multiple steps (1) to (4) described above (for example, steps (1) and (2), steps (2) and (3), and steps (1) to (3)) may be performed consecutively.

[0123] Furthermore, at any stage before or after step 4, the substituents on the nucleic acid base ring may be modified as appropriate (for example, benzoylation or acetylation of the amino substituent of the cytosine ring).

[0124] (Aryl Compounds) The method for producing the so-called aryl compounds of the present invention, in which X in general formula I is the group represented by formula (II-2), is described below. An example of the production scheme is shown in reaction scheme 3 below. Reaction Scheme 3

[0125] (Step 1) Before carrying out the arylation reaction using the starting compound 1 as a starting material by a known method, the nucleic acid base portion (represented by abbreviation B) in the starting compound 1 may be replaced with another protected nucleic acid base portion (represented by abbreviation B') in a nucleic acid base exchange reaction, similar to Step 1 of the reaction scheme 1, before carrying out the arylation reaction. The nucleic acid base exchange reaction (transglycosyl reaction) is carried out by a known method in which the pyrimidine base portion of a nucleic acid base such as thymine (T) or uracil (U) is replaced with another protected nucleic acid base portion (for example, adenine (A), guanine (G), uracil (U), thymine (T), cytosine (C), or 5-methylcytosine ( Ｍｅ By substituting with C), an intermediate compound 8 in which the nucleic acid base portion has been exchanged can be produced. This base exchange reaction can be carried out in the presence of a Lewis acid (e.g., TMSOTf, TBSOTf), and the reaction can be accelerated by reacting with a silylating agent (e.g., BSA). Furthermore, the introduction of this hydroxyl group protecting group can be carried out under reaction conditions well known in organic synthesis chemistry (e.g., nucleic acid synthesis), depending on the type of protecting group. For example, if the hydroxyl group protecting group is a silyl protecting group (e.g., TMS), a silylating agent (e.g., BSA, hexamethyldisilazane, TMS chloride) can be used. In this case, a Lewis acid (e.g., TMSOTf, TBSOTf, tin chloride) may be added. The silylating agent can be used in amounts of about 1 to about 20 molar equivalents relative to the reaction substrate, and the Lewis acid can be used in amounts of a catalytic amount (about 0.05 molar equivalents) to 2 molar equivalents. Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (for example, ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, and chloroform, hydrogen carbides such as benzene and toluene, acetonitrile, water, or a mixture thereof). The reaction proceeds preferably at temperatures from 0°C to high temperatures, particularly from room temperature to about 60°C.

[0126] (Step 2) Next, using starting compound 1 or intermediate compound 8 as a starting material, the arylation reagent is reacted with the starting compound 1 or intermediate compound 8 by a known method to aromatize the imino nitrogen atom and produce intermediate compound 9. Examples of arylation reagents used in the aromatization reaction include desired aryl halide compounds (e.g., chloropyrimidine, dichloropyrimidine, fluoropyrazine, chlorotriazole, chlorooxadiazole, or chlorothiadiazole), and can be used in the presence of a base (e.g., DIPEA). The arylation reagent can be used in an amount of about 1 to about 10 molar equivalents, preferably about 1 to about 5 molar equivalents (e.g., about 3 molar equivalents) relative to the reaction substrate. Any solvent that does not affect the reaction can be used, and the reaction can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, aprotic polar solvents such as DMSO, or mixed solvents thereof). The reaction proceeds preferably at room temperature to high temperatures, particularly at high temperatures (e.g., 120-130°C).

[0127] (Step 3) Furthermore, similar to Step 4 of Reaction Scheme 1, intermediate compound 9 or intermediate compound 8 is used as a starting material and phosphoramidized by a known method to produce the desired aryl series (e.g., aromatic series and heteroaryl series) compounds of the present invention. Examples of phosphoramidizing reagents include 2-cyanoethyl-N,N-diisopropylchlorophosphoramidite, which can be used in the presence of a base (e.g., triethylamine, DIPEA). The phosphoramidizing reagent can be used in amounts of 1 to 10 molar equivalents, preferably 1 to 5 molar equivalents (e.g., 3 molar equivalents), relative to the reaction substrate. Any solvent that does not affect the reaction can be used, and the procedure can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, acetonitrile, or a mixture thereof). The reaction proceeds preferably at temperatures between -25°C and 60°C, particularly between 0°C and room temperature.

[0128] Furthermore, any of the above steps (1) to (3) may be performed consecutively (for example, step (1) and step (2)).

[0129] Furthermore, at any stage before or after step 3, the substituents on the nucleic acid base ring may be modified as appropriate (for example, benzoylation or acetylation of the amino substituent on the cytosine ring), or the substituents on the aromatic ring of the introduced aryl group may be modified (for example, conversion of the chloro group to an amino group), or both of these modifications may be performed.

[0130] (Alternative method for nucleic acid base exchange) Instead of the nucleic acid base exchange reaction described in Step 1, partial replacement of nucleic acid bases may be performed using the series of reactions shown in Reaction Scheme 4 below. Such a series of reactions can be carried out according to the method described in the literature (e.g., C.H. Kim et al., J. Med. Chem. 1987, 30, 862). Reaction Scheme 4

[0131] (Step A) Using intermediate compound 9' (for example, intermediate compound 2 obtained in Step 2 above), in which the nucleic acid base portion is thymine, as a starting material, an acetylating reagent (for example, acetic anhydride) is reacted in the presence of a base (for example, pyridine) to produce intermediate compound A in which the hydroxyl group is acylated. A catalytic amount of DMAP may be added as a reaction activator as appropriate. The acetylating reagent can be used in an amount of about 1 to 3 molar equivalents (for example, about 1.5 molar equivalents) relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (ethers such as THF, or pyridine used as a base). The reaction preferably proceeds at a temperature of 0°C to high (for example, room temperature).

[0132] (Step B) Next, using intermediate compound A as a starting material, the thymine moiety is activated with a chloroforming agent such as phosphorus oxychloride, and then 1,2,4-triazole is reacted in the presence of a base (e.g., DIPEA) to produce intermediate compound B in which the nucleic acid base portion is substituted with a 1,2,4-triazole group. 1,2,4-triazole can be used in excess molar equivalents (approximately 5 to 20 molar equivalents (e.g., approximately 9 to 10 molar equivalents)) relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (ethers such as THF, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, acetonitrile, or a mixture thereof). The reaction preferably proceeds at a temperature of -25°C to room temperature, particularly 0°C to room temperature.

[0133] (Step C) Using intermediate compound B as a starting material, the reaction is carried out with a base (e.g., aqueous ammonia) to remove the acetyl group introduced in step A and the 1,2,4-triazole group modified in step B, thereby producing intermediate compound C in which the nucleic acid base portion is 5-methylcytosine. Ammonia water (e.g., 28% aqueous ammonia) can be used in excess molar equivalent relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (ethers such as THF, acetonitrile, or a mixture thereof). The reaction proceeds preferably at a temperature of 0°C to room temperature, particularly at room temperature.

[0134] Using the obtained intermediate compound C as a starting material, the substituents on the nucleic acid base ring are modified as appropriate (for example, benzoylation or acetylation of the amino substituent on the cytosine ring), or the substituents on the aromatic ring of the introduced aryl group are modified (for example, conversion of a chloro group to an amino group), and then phosphoramidite is performed to produce the desired aryl series (e.g., aromatic series and heteroaryl series) of the present invention.

[0135] (Alternative method for aromatization 1) Furthermore, instead of aromatization using the arylating reagent described in step 2, aromatization may be carried out using the series of reactions shown in reaction scheme 5 below. Reaction scheme 5

[0136] (Step D) The starting compound 1 is reacted with a thioureating reagent (e.g., 1,1-thiocarbonyldiimidazole), and treated with aqueous ammonia to produce an intermediate compound D that has been thioureated on the imino nitrogen atom. The thioureating reagent can be used in an amount of about 1 to 5 molar equivalents, particularly about 2 molar equivalents, relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the process can be carried out in a suitable solvent (such as ethers like THF). The reaction preferably proceeds at a temperature of 0°C to room temperature (e.g., room temperature).

[0137] (Step E) Next, intermediate compound D is used as a starting material and reacted with a methylating reagent (e.g., methyl iodide) to produce an S-methylated and carboimidized intermediate compound E. The methylating reagent can be used in amounts of about 1 to 5 molar equivalents, particularly 3 molar equivalents, relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (such as ethers like THF). The reaction preferably proceeds at a temperature of 0°C to room temperature (e.g., room temperature).

[0138] (Step F) Intermediate compound F is produced by reacting intermediate compound E as a starting material with an acetylating reagent (e.g., acetic anhydride) and a base (e.g., pyridine) to acylate the carboimide group and the hydroxyl group. A catalytic amount of DMAP may be added as a reaction activator as appropriate. The acetylating reagent can be used in amounts of about 1 to 5 molar equivalents (e.g., about 3 molar equivalents) relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (ethers such as THF, or pyridine used as a base). The reaction preferably proceeds at temperatures from 0°C to high temperatures (e.g., room temperature).

[0139] (Step G) Using intermediate compound F as a starting material, intermediate compound G is produced by a ring-closing reaction with methylhydrazine to form a 1,2,4-triazole ring. Methylhydrazine can be used in excess molar equivalents (approximately 5 to 20 molar equivalents (for example, approximately 10 molar equivalents)) relative to the reaction substrate. Any solvent that does not affect the reaction is acceptable, and the reaction can be carried out in a suitable solvent (such as an alcohol solvent like ethanol). The reaction preferably proceeds at a temperature of 0°C to high temperatures (for example, room temperature).

[0140] The obtained intermediate compound G is used as a starting material to modify the substituents on the nucleic acid base ring as appropriate (for example, benzoylation of the amino substituent on the cytosine ring), or to modify the substituent on the aromatic ring of the introduced aryl group (for example, conversion of the chloro group to an amino group), and then phosphoramidite is performed to produce the desired aryl series (for example, aromatic series and heteroaryl series) of the present invention.

[0141] (Oligomer manufacturing process)

[0142] The compound of the present invention or a salt thereof can be used as a monomer starting material for producing oligonucleotides. Oligonucleotides can be synthesized by oligomerizing the compound represented by general formula (I) or a salt thereof, and then deprotecting the amino protecting group and hydroxyl protecting group as needed. The oligomerization reaction is not limited to methods that are generally known in synthetic chemistry (especially nucleic acid synthesis), but can be carried out by, for example, the phosphoramidite-phosphoramidite method. The phosphoramidite-phosphoramidite method can be carried out by, for example, a method similar to the method described in WO 2014 / 046212A1. By this oligomerization reaction, oligonucleotides having one or more nucleotides represented by general formula (I) can be produced.

[0143] In other words, the method for producing oligonucleotides represented by general formula (I') includes the following steps: a) After carrying out an oligomerization reaction using a compound represented by general formula (I) or a salt thereof, the amino protecting group and hydroxyl protecting group are deprotected as needed.

[0144] Furthermore, a method for producing a compound represented by general formula (I) or a salt thereof may include at least one of the following steps from the steps described herein: A step of producing the compound of the present invention or a salt thereof. For example, a step of producing a compound represented by general formula (I') or a salt thereof by subjecting a compound represented by intermediate compound 4, 7, or 9 or a salt thereof to a phosphoramidite reaction. For example, a step of producing a compound represented by intermediate compound 4, 7, or 9 by deprotecting the protecting group of the hydroxyl group of a compound represented by intermediate compound 3 or 6.

[0145] (Method for producing phosphorothioate oligomers) In the synthesis of oligonucleotides by the phosphoramidite method, an oxidizing agent is used to convert the phosphite group to a phosphate group. If DDTT (((dimethylamino-methylidene)amino)-3H-1,2,4-dithiazaolin-3-thione) or Beaucage reagent (3H-1,2-benzodithiol-3-one-1,1-dioxide) is used instead of the oxidizing agent used at this time, a phosphorothioate oligomer with a protecting group is obtained in which the oxygen atom at P=O of the phosphate group is replaced with sulfur as P=S, resulting in a thiophosphate group.

[0146] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Compound identification was performed by mass spectrometry, high-performance liquid chromatography-mass spectrometry (LCMS), NMR spectrometry, high-performance liquid chromatography (HPLC), etc. Hydrogen nuclear magnetic resonance (NMR) １ In H-NMR, a resonance frequency of 400 MHz is used for phosphorus nuclear magnetic resonance ( ３１For P-NMR, a sensor with a resonant frequency of 161.8 MHz was used. The symbols used in NMR are as follows: s for single line, d for double line, dd for double double line, t for triple line, td for triple double line, q for quadruple line, quin for quinuple line, sept for heptapyl line, m for multiline line, br for broad line, brs for broad single line, brd for broad double line, brt for broad triple line, and J for coupling constant.

[0147] The structure and abbreviation (abbreviated as appropriate in this specification) of each artificial nucleic acid are shown in the following structural formula. Structure and abbreviation of each artificial nucleic acid

[0148] Synthesis of ALNA[Ms]-T

[0149] Example 1 Synthesis of Compound 2Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione (1a) (12.35 g, To a mixed solution of 21.61 mmol of dichloromethane (61 mL), BSA (13 mL, 53.17 mmol) was added, and the mixture was stirred at room temperature for 8 hours. BSA (5.2 mL, 21 mmol) and TMSOTf (200 μL, 1.0 mmol) were then added, and the mixture was stirred again at room temperature for 15 hours. 5% sodium bicarbonate solution (50 mL) was added to the reaction mixture and stirred, and the mixture was extracted with dichloromethane. The aqueous layer was mixed with dichloromethane (61 mL), extracted, and the organic layer of dichloromethane was combined and mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 98 / 2) to obtain compound 2Ta (10.49 g, yield 75%). MS (ESI): m / z = 644 (M + H) ＋

[0150] Example 2 Synthesis of Compound 2Tb 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-methylsulfonyl-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 2Ta (10.19 g, 15.83 mmol) was mixed with dichloromethane (50 mL) and DIPEA (5.4 mL, 31 mmol) was added. Mesylchloride (1.4 mL, 18 mmol) was added under ice bath conditions, and the mixture was stirred under ice bath conditions for 1.5 hours. 5% sodium bicarbonate solution (20 mL) was added to the reaction solution and stirred, and extracted with dichloromethane. The aqueous layer was mixed with dichloromethane (20 mL), extracted, and the organic layer of dichloromethane was combined and mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0–98 / 2) to obtain compound 2Tb (6.56 g, 57% yield). MS (ESI): m / z = 720 (M–H) －

[0151] Example 3 Synthesis of Compound 2Tc 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 2Tb (3.02 g, 4.13 mmol) was mixed with tetrahydrofuran (15 mL) and TBAF (1.35 mL, 4.58 mmol, 1 M tetrahydrofuran solution) was added under an ice bath, and the mixture was stirred for 30 minutes. 10% aqueous ammonium chloride solution (20 mL) and dichloromethane (20 mL) were added to the reaction mixture and stirred, and the mixture was extracted with dichloromethane. The aqueous layer was mixed with dichloromethane (20 mL), extracted, and the organic layer of dichloromethane was mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0–98 / 2) to obtain compound 2Tc (2.47 g, 92% yield). MS (ESI): m / z = 648 (M–H) －

[0152] Example 4 Compound 2Td 3-[[(1R,4R,6R,7S)-4-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-6-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-methylsulfonyl-5-oxa-2-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 1 of the present invention) Compound 2Tc (2.47 g, 3.80 mmol) was dissolved in dichloromethane (12.5 mL) and DIPEA (2.00 mL, 12.0 mmol) and 2-cyanoethyl N,N,N',N'-diisopropylchlorophosphoramidite (2.10 mL, 9.40 mmol) were added under ice cooling, and the mixture was stirred at room temperature for 5 hours. To this, 15 mL of 5% sodium bicarbonate aqueous solution and 10 mL of dichloromethane were added under ice cooling, and the mixture was stirred at room temperature. Extraction with dichloromethane was then performed. The aqueous layer was extracted with 10 mL of dichloromethane, and the organic layer of dichloromethane was combined and mixed. After removing the solvent under reduced pressure, the mixture was purified by silica gel column chromatography (hexane / ethyl acetate, 60 / 40 to 40 / 60) to obtain compound 2Td (2.13 g, yield 66%), which is compound 1 of the present invention. MS (ESI): m / z = 850 (M + H) ＋ 31 P-NMR (CDCl3) δ: 150.30, 149.12

[0153] Synthesis of ALNA[Ms]-mC

[0154] Example 5 Synthesis of Compound 2mCc N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 1a (10.33 g, 18.1 mmol) and N-(5-methyl-2-oxo-1H-pyrimidine-4-yl)benzamide (12.42 g, 54.2 mmol) were suspended in toluene (180 mL), to which BSA (44 mL, 180 mmol) was added, and the mixture was stirred at room temperature for 15 minutes. TMSOTf (0.52 mL, 2.71 mmol) was added, and the mixture was stirred at room temperature for 2 hours. The reaction mixture was added to a mixture of IPE (100 mL), saturated sodium bicarbonate solution (50 mL), and water (50 mL). The mixture was stirred for 10 minutes, and insoluble materials were filtered off with Celite. The aqueous layer was removed from the filtrate, and the organic layer was washed sequentially with water (50 mL) and saturated saline solution (50 mL). The mixture was passed through a phase separator, and the solvent was removed by distillation. Dichloromethane (90 mL) was added to the residue to dissolve it, and triethylamine (5.0 mL, 36.0 mmol) and methanesulfonic anhydride (3463 mg, 19.9 mmol) were added. The mixture was stirred at room temperature for 40 minutes. Methanesulfonic anhydride (944 mg, 5.42 mmol) was added, and the mixture was stirred at room temperature for 30 minutes. Further additions of methanesulfonic anhydride (944 mg, 5.42 mmol) and triethylamine (1.3 mL, 9.06 mmol) were added, and the mixture was stirred at room temperature for 20 minutes. The mixture was diluted with ethyl acetate (80 mL), and water (40 mL) and saturated sodium bicarbonate solution (40 mL) were added, and the mixture was stirred. After removing the aqueous layer, the organic layer was washed with saturated brine (50 mL), and the solvent was removed by passing the mixture through a phase separator and vacuum drying was performed. THF (90 mL) was added to the residue to make a solution, and TBAF (0.1 M THF solution, 21.7 mL, 21.7 mmol) was added under ice cooling, and the mixture was stirred under ice cooling for 15 minutes. The mixture was diluted with ethyl acetate (90 mL), and saturated ammonium chloride aqueous solution (40 mL) and water (40 mL) were added and the mixture was stirred. After removing the aqueous layer, the solvent was removed by passing the mixture through a phase separator.The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 95 / 5) to obtain 2 mCc of compound (5702 mg, 38% yield in 3 steps). MS (ESI): m / z = 753 (M + H). ＋

[0155] Example 6 Synthesis of Compound 2mCd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 2 of the present invention) Compound 2mCd (6809 mg, yield 72%) was obtained from Compound 2mCc (8099 mg, 9.89 mmol) in the same manner as in Example 4. MS (APCI): m / z = 954 (M + H) ＋

[0156] Synthesis of ALNA[Ms]-G

[0157] Example 7 Synthesis of Compound 2Ga [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate Compound 1a (5040 mg, 8.817 mmol) and [2-(2-methylpropanoylamino)-9H-purin-6-yl]N,N-diphenylcarbamate (5400 mg, 12.97 mmol) were dissolved in 1,2-dichloroethane (24.7 mL), to which BSA (14.8 mL, 60.46 mmol) was added, and the mixture was stirred at 64°C for 1 hour. Next, TMSOTf (0.167 mL, 0.864 mmol) was gradually added while maintaining an internal temperature of 60°C, and the mixture was stirred for 1 hour. After cooling, the reaction solution was gradually added to a separately prepared mixed solution of chloroform (40 mL) and saturated sodium bicarbonate aqueous solution (40 mL), and the mixture was stirred. After suction filtration of insoluble matter, the filtrate was extracted with ethyl acetate (50 mL). The organic layer was washed with saturated brine (50 mL) and then dried over sodium sulfate. Subsequently, the filtrate was removed by vacuum distillation, and the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 97 / 3) to obtain compound 2Ga (6350 mg, yield 79%). MS (ESI): m / z = 935 (M + H) ＋

[0158] Example 8 Synthesis of Compound 2Gb [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-methylsulfonyl-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate A solution of Compound 2Ga (2370 mg, 2.537 mmol) in dichloromethane (24.9 mL) was mixed with triethylamine (0.692 mL, 4.984 mmol) and the mixture was stirred at room temperature for 5 minutes. Subsequently, methanesulfonyl chloride (0.193 mL, 2.488 mmol) was added to the mixture under ice cooling and the mixture was stirred for 1 hour. Under ice cooling, methylene chloride (30 mL) and saturated sodium bicarbonate aqueous solution (30 mL) were added to the reaction mixture and stirred, followed by liquid-liquid separation. The organic layer was washed with saturated brine (30 mL) and then dried over sodium sulfate. Subsequently, the filtrate was removed by reduced pressure distillation, and the resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 67 / 33 to 50 / 50) to obtain 2 Gb of compound (2210 mg, yield 88%). MS (ESI): m / z = 10¹³ (M + H) ＋

[0159] Example 9 Synthesis of Compound 2Gc [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate A solution of Compound 2Gb (2200 mg, 2.173 mmol) in THF (11 mL) was mixed with TBAF (2.4 mL, 3.407 mmol) under ice cooling, and the mixture was stirred at room temperature for 5 hours. Under ice cooling, ethyl acetate (30 mL) and saturated ammonium chloride aqueous solution (30 mL) were added to the reaction mixture and stirred, then separated. The organic layer was washed with saturated brine (30 mL) and dried over sodium sulfate. Next, the filtrate was removed by reduced-pressure distillation, and the resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 60 / 40 to 50 / 50). Further purification by silica gel column chromatography (chloroform / methanol, 100 / 0 to 97 / 3) was performed to remove the starting material, yielding compound 2Gc (1070 mg, 52% yield). MS (ESI): m / z = 941 (M+H) ＋

[0160] Example 10 Synthesis of Compound 2Gd [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (Compound 3 of the present invention) Compound 2Gc (1070 mg, 1.139 mmol) was dissolved in dichloromethane (5.690 mL) and DIPEA (0.590 mL, 3.407 mmol) and 2-cyanoethyl-N,N-diisopropylchlorophosphoramidite (0.510 mL, 2.282 mmol) were added to a solution of Compound 2Gc (1070 mg, 1.139 mmol) in dichloromethane (5.690 mL) under ice cooling, and the mixture was stirred at room temperature for 22 hours. Under ice cooling, dichloromethane (20 mL) and saturated sodium bicarbonate solution (20 mL) were added to the reaction mixture and stirred, followed by liquid-liquid separation. After removing the aqueous layer, the organic layer was passed through a phase separator. After removing the filtrate under reduced pressure, the resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 40 / 60) to obtain compound 2Gd (548 mg, 42% yield), which is compound 3 of the present invention. MS (ESI): m / z = 1141 (M + H) ＋

[0161] Synthesis of ALNA[Ms]-A

[0162] Example 11 Synthesis of Compound 2Ac N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purine-6-yl]benzamide Compound 1a (10.0 g, 17.6 mmol) and N-(9H-purine-6-yl)benzamide (5.04 g, 21.1 mmol) were suspended in toluene (176 mL), to which BSA (30 mL, 123 mmol) was added dropwise, and the mixture was heated to 60°C and stirred for 30 minutes. TMSOTf (1.03 mL, 5.34 mmol) was added, and the mixture was stirred at 60°C for 15 minutes. Under ice cooling, the reaction solution was added to a mixture of IPE (100 mL) and saturated sodium bicarbonate solution (100 mL) while stirring, and the mixture was stirred for 20 minutes to remove insoluble matter. The residue was then Et ２ After washing twice with 20 mL of oxygen, the filtrate was separated and washed with saturated saline (50 mL). After passing through a phase separator, the mixture was concentrated under reduced pressure. Dichloromethane (24.9 mL) was added to the residue to dissolve it, and pyridine (4.57 mL, 56.5 mmol) and methanesulfonic anhydride (3614 mg, 20.75 mmol) were added, and the mixture was stirred at room temperature for 30 minutes. Saturated sodium bicarbonate aqueous solution (50 mL) and water (50 mL) were added, and the mixture was stirred and separated. The organic layer was washed with saturated saline (50 mL), passed through a phase separator, and the solvent was removed under reduced pressure. THF (88 mL) was added to the residue to make a solution, and TBAF (1 M THF solution, 21.1 mL, 21.1 mmol) was added under ice cooling, and the mixture was stirred under ice cooling for 30 minutes. The solution was diluted with ethyl acetate (80 mL), and saturated ammonium chloride aqueous solution (50 mL) and water (50 mL) were added. The mixture was stirred at room temperature. After liquid-liquid separation, the organic layer was washed with saturated brine (50 mL), and the solvent was removed by passing it through a phase separator. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 95 / 5) to obtain compound 2Ac (10.6 g, 75% yield in 3 steps). MS (ESI): m / z = 763 (M + H) ＋

[0163] Example 12 Synthesis of Compound 2Ad N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purine-6-yl]benzamide (Compound 4 of the present invention) To a solution of Compound 2Ac (5.60 mg, 7.01 mmol) in dichloromethane (40 mL), DIPEA (4.8 mL, 28.0 mmol) and 2-cyanoethyl-N,N-diisopropylchlorophosphoramidite (4.7 mL, 21.0 mmol) were added under ice cooling, and the mixture was stirred at room temperature for 4 hours. Ethanol (1.2 mL, 21.0 mmol) was added under ice cooling, and the mixture was stirred at room temperature for 5 minutes. The mixture was again cooled on ice, and saturated sodium bicarbonate solution (20 mL) and saturated saline solution (20 mL) were added and stirred. The organic layer was then passed through a phase separator. After removing the filtrate under reduced pressure, the resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 67 / 33 to 10 / 90) to obtain compound 2Ad (5.44 g, 77% yield), which is compound 4 of the present invention. MS (ESI): m / z = 964 (M + H) ＋

[0164] Synthesis of ALNA[Bs]-T

[0165] Example 13 Synthesis of Compound 3Tb 1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 2Ta (1.00 g, 1.56 mmol) was azeotropically dissolved in toluene. Dichloromethane (5 mL) and triethylamine (0.43 mL, 3.1 mmol) were added to the residue and dissolved completely. The mixed solution was cooled on ice, benzenesulfonyl chloride (0.21 mL, 1.6 mmol) was added, and the mixture was stirred on ice for 4 hours. 5% aqueous potassium carbonate solution (20 mL) was added to the reaction solution and stirred, and the mixture was extracted with dichloromethane (5 mL). The aqueous layer was mixed with dichloromethane (5 mL), extracted, and the organic layer of dichloromethane was combined and mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 40 / 60 to 20 / 80) to obtain compound 3Tb (0.78 g, yield 64%). MS (ESI): m / z = 782 (M-H) －

[0166] Example 14 Synthesis of Compound 3Tc 1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 3Tc (0.59 g, yield 84%) was synthesized from Compound 3Tb (0.78 g, 0.99 mmol) in the same manner as in Example 3. MS (ESI): m / z = 710 (M-H) －

[0167] Example 15 Synthesis of Compound 3Td 3-[[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopronylamino)phosphanyl]oxypropanenitrile (Compound 5 of the present invention) To a solution of Compound 3Tc (599 mg, 0.765 mmol) in acetonitrile (3 mL), diisopropylammonium tetrazolide (171 mg, 0.996 mmol) and 3-bis(diisopropylamino)phosphanyloxypropanenitrile (0.36 mL, 1.1 mmol) were added, and the mixture was stirred at room temperature for 19 hours. Ethyl acetate (10 mL) and water (5 mL) were added to the reaction mixture, and after stirring, the aqueous layer was separated. Ethyl acetate (10 mL) was added to the aqueous layer, and after mixing, the organic layer was separated. The organic layers were combined and mixed, and concentrated under reduced pressure at 40°C. The resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 67 / 33 to 10 / 90) to synthesize compound 3Td (0.65 g, yield 86%) as compound 5 of the present invention. MS (ESI): m / z = 912 (M + H) ＋ 31 P-NMR (CDCl3) δ: 149.68, 149.22

[0168] Synthesis of ALNA[Bs]-mC

[0169] Example 16 Synthesis of Compound 3Cb N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 3mCb (0.85 g, yield 71%) was synthesized from compound 1b (1.00 g, 1.34 mmol) synthesized by the method described in International Publication No. 2017 / 047816, in the same manner as in Example 13. MS (ESI): m / z = 887 (M+H) ＋

[0170] Example 17 Synthesis of compound 3mCb N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 3mCc (0.78 g, 99% yield) was synthesized from compound 3mCb (0.85 g, 0.96 mmol) in the same manner as in Example 14. MS (ESI): m / z = 813 (M+H) ＋

[0171] Example 18 Synthesis of Compound 3mCd N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl)oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Inventive Compound 6) Compound 3mCd (0.53 g, yield 55%) was synthesized from Compound 3mCc (0.78 g, 0.89 mmol) in the same manner as in Example 15. MS (ESI): m / z = 10¹⁵ (M + H) ＋ 31 P-NMR (CDCl3) δ: 149.94, 149.34

[0172] Synthesis of ALNA[mU]-T

[0173] Example 19 Synthesis of Compound 4Tc (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N-methyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Compound 1a (1.20 g, 2.10 mmol) was azeotropically heated in toluene, and N-diisopropyl-N-ethylamine (0.61 mL, 3.5 mmol) was added to the residue mixed with tetrahydrofuran (6 mL). Then, a tetrahydrofuran solution (1 mL) of N-methylcarbamoyl chloride (0.20 g, 2.2 mmol) was added under ice bath conditions, and the mixture was stirred under ice bath conditions for 3 hours. 5% sodium bicarbonate solution (20 mL) and ethyl acetate (10 mL) were added to the reaction solution and stirred, and the mixture was extracted with ethyl acetate. The aqueous layer was extracted twice with ethyl acetate (10 mL), and the organic layer was combined and mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 97 / 3) to obtain compound 4Tc (1.28 g, 97% yield). MS (ESI): m / z = 627 (M-H) －

[0174] Example 20 Synthesis of Compound 4Td (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 7 of the present invention) Compound 4Td (0.56 g, yield 37%) was synthesized from Compound 4Tc (1.16 g, 1.8 mmol) in the same manner as in Example 15. MS (ESI): m / z = 828 (M-H) － 31 P-NMR (CDCl3) δ: 149.31, 147.44

[0175] Synthesis of ALNA[mU]-mC

[0176] Example 21 Synthesis of Compound 4mCa 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 1a (105.0 g, 184 mmol), 5-methylcytosine (69.0 g, 551 mmol), and 1,2-dichloroethane (918 mL) was mixed with BSA (584 mL, 2390 mmol) added dropwise over 18 minutes. The mixture was heated to 60°C and stirred for 20 minutes. After cooling to 19.5°C by ice cooling, TMSOTf (10 mL, 55.2 mmol) was added and the mixture was heated to 60°C. After stirring for 40 minutes, the reaction mixture was cooled on ice, and 525 mL of 5% sodium bicarbonate aqueous solution was added dropwise. Then, 1050 mL of chloroform and 525 mL of 15% sodium chloride aqueous solution were added. The resulting slurry was filtered through Celite, and the residue was washed with chloroform (525 mL) to obtain residue 1 and filtrate 1. Ethyl acetate (2100 mL) and water (2100 mL) were added to residue 1, and the mixture was stirred for 1 hour. After filtering this through Celite, the residue was washed with ethyl acetate (1050 mL) to obtain filtrate 2. Filtrate 2 was separated, and the organic layer was washed twice with water (525 mL). Meanwhile, filtrate 1 was separated, and the aqueous layer was extracted with chloroform (525 mL). The organic layers were combined and washed twice with 1050 mL of water. The obtained organic layer was concentrated under reduced pressure to obtain a pale yellow solid (125.6 g). THF (550 mL) was added and the mixture was stirred, then 1 M TBAF / THF solution (276 mL, 276 mmol) was added. After stirring at room temperature for 3 hours, water (550 mL) was added to the reaction mixture to quench it, and then chloroform (550 mL) was added and the mixture was separated. The aqueous layer was extracted again with chloroform (275 mL), and the organic layer was combined with the aqueous layer. The organic layer was washed with water and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 20 / 1 to 4 / 1) to obtain compound 4 mCa (69.62 g, yield 62%). MS (ESI): m / z = 593 (M + Na) ＋

[0177] Example 22 Synthesis of Compound 4mCb (1R,3R,4R,7S)-3-(4-amino-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Compound 4mCa (1.00 g, 1.75 mmol) was azeotropically dissolved in toluene, and triethylamine (0.49 mL, 3.5 mmol) was added to the residue mixed with tetrahydrofuran (5 mL). A tetrahydrofuran solution (1 mL) of N-methylcarbamoyl chloride (0.17 g, 1.8 mmol) was added under ice bath conditions, and the mixture was stirred under ice bath conditions for 3 hours. Tap water (15 mL), ethyl acetate (1 mL), and chloroform (15 mL) were added to the reaction mixture and stirred, and the mixture was extracted with an organic solvent. The aqueous layer was extracted with chloroform (5 mL), and the organic layer was combined and mixed. The organic layer was dried over magnesium sulfate, and the solid was filtered. The filtrate was removed by solvent distillation to obtain compound 4 mCb (1.18 g, yield quant.). The residue was used in the next reaction without purification. MS (ESI): m / z = 627 (M-H) －

[0178] Example 23 Synthesis of compound 4mCc (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Compound 4mCb (1.18 g) was azeotropically dissolved in toluene, and benzoic anhydride (0.51 g, 2.27 mmol) and methanol (0.01 mL, 0.25 mmol) were added to the residue mixed with tetrahydrofuran (5 mL) at room temperature, and the mixture was stirred in an external bath at 70°C for 4 hours. 5% sodium bicarbonate solution (10 mL) and ethyl acetate (10 mL) were added and stirred, and the mixture was extracted with an organic solvent. The aqueous layer was extracted with ethyl acetate (15 mL), and the organic layers were combined and mixed. After removing the solvent from the organic layer, the resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0–97 / 3) to obtain 4 mCc of compound (0.99 g, 77% yield). MS (ESI): m / z = 731 (M–H) －

[0179] Example 24 Synthesis of Compound 4mCd (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Compound 8 of the present invention) Compound 4mCd (0.96 g, yield 77%) was synthesized from Compound 4mCc (0.98 g, 1.34 mmol) in the same manner as in Example 15. MS (ESI): m / z = 933 (M+H) ＋

[0180] Synthesis of ALNA[mU]-G

[0181] Example 25 Synthesis of Compound 4Ga [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate Compound 1a (30.5 g, 53.4 mmol) and [2-(2-methylpropanoylamino)-9H-purine-6-yl]N,N-diphenylcarbamate (26.7 g, 64.1 mmol) were suspended in toluene (267 mL), to which BSA (91 mL, 372 mmol) was added dropwise over approximately 20 minutes. The mixture was heated to 60°C and stirred for 5 minutes. Toluene (100 mL) was added, and the mixture was stirred further at 60°C for 10 minutes. TMSOTf (1.03 mL, 5.34 mmol) was added, and the mixture was stirred at 60°C for 20 minutes. Under ice cooling, the reaction mixture was added to a mixture of IPE (100 mL), saturated sodium bicarbonate solution (50 mL), and water (50 mL) while stirring, and the mixture was stirred for 2 hours, after which insoluble matter was filtered off. The residue was Et ２ After washing twice with 20 mL of oxygen, the filtrate was separated, and the organic layer was sequentially washed with 50 mL of water and 50 mL of saturated saline solution. The mixture was passed through a phase separator, concentrated under reduced pressure, and vacuum-dried to obtain 4 Ga (48.67 g) as the crude product. MS (ESI): m / z = 954 (M + H) ＋

[0182] Example 26 Synthesis of Compound 4Gc [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate Compound 4Ga (17.4 g, 18.6 mmol) was dissolved in THF (100 mL), and DIPEA (4.87 mL, 28.0 mmol) and N-methylcarbamoyl chloride (1830 mg, 19.6 mmol) were added under ice cooling, and the mixture was stirred for 30 minutes. Saturated sodium bicarbonate solution (100 mL) and ethyl acetate (100 mL) were added sequentially, and the mixture was stirred for 5 minutes at room temperature. After liquid-liquid separation, the organic layer was sequentially washed with water (50 mL) and saturated saline solution (50 mL), then passed through a phase separator to remove the solvent, and vacuum-dried. THF (90 mL) was added to the residue to form a solution, and TBAF (1 M THF solution, 4.54 mL, 4.54 mmol) was added under ice cooling. The mixture was stirred under ice cooling for 20 minutes. Dilution with ethyl acetate (100 mL), saturated ammonium chloride aqueous solution (50 mL), and water (50 mL) were added, and the mixture was stirred at room temperature for 5 minutes. After liquid-liquid separation, the organic layer was passed through a phase separator to remove the solvent. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 95 / 5) to obtain compound 4Gc (9030 mg, 54% yield in 3 steps). MS (ESI): m / z = 919 (M + H) ＋

[0183] Example 27 Synthesis of Compound 4Gd [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(methylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (Compound 9 of the present invention) Compound 4Cd (8700 mg, yield 79%) was synthesized from Compound 4Gc (9020 mg, 9.82 mmol) in the same manner as in Example 12. MS (ESI): m / z = 1197 (M+H) ＋

[0184] Synthesis of ALNA[mU]-A

[0185] Example 28 Synthesis of Compound 4Aa N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide Compound 1a (30.0 g, 52.5 mmol) and N-(9H-purin-6-yl)benzamide (15.0 g, 62.7 mmol) were suspended in toluene (500 mL), to which BSA (90 mL, 368 mmol) was added dropwise. The mixture was heated to 80°C and stirred for 20 minutes. Then, under ice cooling, TMSOTf (1.0 mL, 5.17 mmol) was added, and the mixture was stirred at 60°C for 20 minutes. The reaction solution was added to a mixture of IPE (200 mL) and saturated sodium bicarbonate solution (200 mL) being stirred under ice cooling, and the mixture was stirred for 20 minutes to remove insoluble matter. The residue was then Et ２ After washing twice with 40 mL of oxygen, the filtrate was separated and washed with saturated saline solution. The organic layer was dried over sodium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure and vacuum-dried to obtain 4Aa (40.5 g) as the crude product. MS (ESI): m / z = 757 (M + H) ＋

[0186] Example 29 Synthesis of Compound 4Ab (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-N-methyl-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Crude product 4Aa (8.20 g) was dissolved in THF (87 mL), and DIPEA (3.00 mL, 17.2 mmol) and N-methylcarbamoyl chloride (970 mg, 10.4 mmol) were sequentially added at room temperature, and the mixture was stirred for 30 minutes. To this, ethyl acetate (100 mL), saturated sodium bicarbonate solution (50 mL), and water (50 mL) were added. After liquid-liquid separation, the organic layer was washed with saturated saline solution (50 mL), the solvent was removed by passing it through a phase separator, and the mixture was vacuum-dried to obtain crude product 4Ab (8.70 g). MS (ESI): m / z = 813 (MH) －

[0187] Example 30 Synthesis of Compound 4Ac (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-hydroxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Crude product 4Ab (8.00 g) was dissolved in THF (100 mL) and TBAF (1 M THF solution, 5.00 mL, 5.00 mmol) was added under ice cooling, and the mixture was stirred under ice cooling for 1 hour. The mixture was diluted with ethyl acetate (80 mL), saturated ammonium chloride aqueous solution (50 mL) and water (50 mL) were added, and the mixture was stirred at room temperature. After liquid-liquid separation, the organic layer was washed with saturated brine (50 mL), and the solvent was removed by passing it through a phase separator. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 97 / 3) to obtain compound 4Ac (6100 mg, 84% yield in 3 steps). MS (ESI): m / z = 742 (M + H) ＋

[0188] Example 31 Synthesis of Compound 4Ad (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 10) 4Ad (3830 mg, yield 48%) as Inventive Compound 10 was obtained from 4Ac (6100 mg, 8.20 mmol) in the same manner as in Example 12. MS (APCI): m / z = 942 (M + H) ＋

[0189] Synthesis of ALNA[ipU]-T

[0190] Example 32 Synthesis of Compound 5Tc (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-hydroxy-N-isopropyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide A solution of Compound 1a (1500 mg, 2.624 mmol) in dichloromethane (26 mL) was mixed with 2-isocyanatepropane (0.27 mL, 2.7 mmol) under ice cooling, and the mixture was stirred at room temperature for 1 hour. A mixture of ethyl acetate (10 mL) and saturated baking soda water (20 mL) was added, and after liquid-liquid extraction, the aqueous layer was extracted twice with 10 mL of ethyl acetate, and the combined organic layer was washed with 10 mL of saturated brine. The organic layer was dried over anhydrous sodium sulfate, filtered, and the solvent was removed by distillation. Compound 5Tc (1904 mg, yield quant.) was obtained by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 0 / 100). MS (ESI): m / z = 656 (MH) －

[0191] Example 33 Synthesis of Compound 5Td (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 11) Compound 5Td (1272.9 mg, yield 52%) as Inventive Compound 11 was obtained from Compound 5Tc (2020 mg, 2.85 mmol) in the same manner as in Example 4. MS (ESI): m / z = 855 (MH) －

[0192] Synthesis of ALNA[ipU]-mC

[0193] Example 34 Synthesis of Compound 5mCc (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-hydroxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Compound 5mCc (1168 mg, yield 93%) was obtained from Compound 1c (1300 mg, 1.657 mmol) synthesized by the method described in International Publication No. 2017 / 047816. MS (ESI): m / z = 761 (M+H) ＋

[0194] Example 35 Synthesis of Compound 5mCd (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 12) Compound 5mCd (1002.8 mg, yield 75%) as Inventive Compound 12 was obtained from Compound 5mCc (1168 mg, 1.378 mmol) in the same manner as in Example 4. MS (ESI): m / z = 961 (M+H) ＋

[0195] Synthesis of ALNA[ipU]-G

[0196] Example 36 Synthesis of Compound 5Gc N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-(isopropylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate Compound 1d (2.42 g, 2.81 mmol) synthesized according to the method described in the example of International Publication No. 2017 / 047816 was dissolved in dichloromethane (28 mL) and isopropyl isocyanate (0.31 mL, 3.09 mmol) was added under ice cooling, and the mixture was stirred at room temperature for 3 hours. Saturated sodium bicarbonate solution was added to the reaction mixture and stirred, and after passing through a phase separator, the solvent was removed by distillation. The residue was purified by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 20 / 80) to obtain compound 5Gc (1.41 g, 53% yield). MS (ESI): m / z = 948 (M + H) ＋

[0197] Example 37 Synthesis of Compound 5Gd [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(isopropylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purine-6-yl]N,N-diphenylcarbamate (Inventive Compound 13) Compound 5Gd (1.20 g, 70% yield) as Inventive Compound 13 was obtained from Compound 5Gc (1.41 g, 1.49 mmol) in the same manner as in Example 4. MS (ESI): m / z = 1148 (M+H) ＋ 31 P-NMR (CDCl3) δ: 149.42, 149.39

[0198] Synthesis of ALNA[ipU]-A

[0199] Example 38 Synthesis of Compound 5Ac (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-carboxamide Compound 1a (10.0 g, 17.5 mmol) and N-(9H-purine-6-yl)benzamide (5.0 g, 21.0 mmol) were suspended in toluene (175 mL), to which BSA (30 mL, 122 mmol) was added dropwise. The mixture was heated to 60°C and stirred for 10 minutes, then TMSOTf (0.34 mL, 1.8 mmol) was added and stirred at 60°C for 15 minutes. Under ice cooling, the reaction solution was added to a mixture of IPE (100 mL) and saturated sodium bicarbonate solution (100 mL) while stirring, and the mixture was stirred for 20 minutes to remove insoluble matter. The residue was then Et ２ After washing with 10 mL of oxygen, the filtrate was separated and washed with saturated saline solution. The organic layer was dried over sodium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. Dichloromethane (162 mL) was added to the residue to dissolve it, and isopropyl isocyanate (1.8 mL, 18 mmol) was added at room temperature, and the mixture was stirred for 60 minutes. Ethyl acetate (100 mL), saturated sodium bicarbonate solution (50 mL), and water (50 mL) were added, and after separation, the organic layer was washed with saturated saline solution (50 mL), dried over sodium sulfate, filtered, and the solvent was removed by distillation. THF (162 mL) was added to the residue to make a solution, and TBAF (1 M THF solution, 2.39 mL, 8.11 mmol) was added under ice cooling, and the mixture was stirred at room temperature for 24 hours. Dilution with ethyl acetate (80 mL), saturated ammonium chloride aqueous solution (50 mL), and water (50 mL) were added, and the mixture was stirred at room temperature. The organic layer was separated, washed with saturated brine (50 mL), dried over sodium sulfate, filtered, and the solvent was removed by distillation. The resulting residue was purified by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 0 / 100) to obtain compound 5Ac (10.1 g, 77% yield in 3 steps). MS (ESI): m / z = 770 (M + H) ＋

[0200] Example 39 Synthesis of Compound 5Ad (1R,3R,4R,7S)-3-(6-benzamidopurine-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 14) Compound 5d (4.6 g, yield 51%) as Inventive Compound 14 was obtained from Compound 5c (7.0 g, 9.09 mmol) in the same manner as in Example 4. MS (ESI): m / z = 970 (M + H) ＋ 31 P-NMR (CDCl3) δ: 149.4

[0201] Synthesis of ALNA[dmU]-T

[0202] Example 40 Synthesis of Compound 6Tc (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N,N-dimethyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide Compound 1a (1512 mg, 2.645 mmol) was dissolved in tetrahydrofuran (26 mL), to which diisopropylethylamine (0.483 mL, 2.773 mmol) was added and the mixture was cooled on ice. Then, N,N-dimethylcarbamoyl chloride (0.255 mL, 2.77 mmol) was added. The mixture was heated to room temperature, and then N,N-dimethylformamide (1 mL, 12.9 mmol) was added and the mixture was stirred for 4 hours. A mixture of ethyl acetate (10 mL) and saturated baking soda water (20 mL) was added and stirred. After liquid-liquid separation, the aqueous layer was extracted twice with 10 mL of ethyl acetate, and the combined organic layer was washed with 10 mL of saturated brine. The organic layer was dried over anhydrous sodium sulfate, filtered, and the solvent was removed by distillation. Compound 6Tc1 (1705 mg, yield quant.) was obtained by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 0 / 100). MS (ESI): m / z = 642 (MH) －

[0203] Example 41 Synthesis of Compound 6Td (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 15) Compound 6Td (1565 mg, yield 68%) as Inventive Compound 15 was obtained from Compound 6Tc (1758 mg, 2.735 mmol) in the same manner as in Example 4. MS (ESI): m / z = 842 (MH) －

[0204] Synthesis of ALNA[dmU]-mC

[0205] Example 42 Synthesis of compound 6mCc (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-N,N-dimethyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide A solution of compound 1c (1300 mg, 1.657 mmol) in tetrahydrofuran (16.6 mL) was mixed with diisopropylethylamine (0.317 mL, 1.820 mmol) and cooled on ice. Then, N,N-dimethylcarbamoyl chloride (0.168 mL, 1.83 mmol) was added, and the mixture was stirred at room temperature for 10 minutes. The mixture was heated under reflux for 2 hours, then added to a mixture of ethyl acetate (10 mL) and saturated baking soda water (20 mL) at room temperature. After liquid-liquid extraction, the aqueous layer was extracted twice with 10 mL of ethyl acetate, and the combined organic layer was washed with 10 mL of saturated brine. The organic layer was dried over anhydrous sodium sulfate, filtered, and the solvent was removed by distillation. Silica gel column chromatography (hexane / ethyl acetate, 70 / 30 to 30 / 70) yielded 6 mCc of the compound (1705 mg, 79% yield). MS (ESI): m / z = 747 (M+H) ＋

[0206] Example 43 Synthesis of Compound 6mCd (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidine-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxamide (Inventive Compound 16) Compound 6mCd (936.5 mg, yield 76%) as Inventive Compound 16 was obtained from Compound 6mCc (1019 mg, 1.312 mmol) in the same manner as in Example 4. MS (ESI): m / z = 947 (M+H) ＋

[0207] Synthesis of ALNA[2Pym]-T

[0208] Example 44 Synthesis of Compound 7Tc 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (2.00 g, 3.50 mmol), 2-chloropyrimidine (1.20 g, 10.5 mmol), DIPEA (3.05 mL, 17.5 mmol), and DMSO (17.5 mL) was stirred at 130°C under a nitrogen atmosphere for 6 hours. Ethyl acetate was added to the reaction mixture and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. The residue was analyzed by column chromatography (SiO2). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 7Tc (1.74 g, 77% yield). HRMS(MALDI): C ３６ H ３５ N ５ O ７ Calculated value [M+Na] + : 672.2429, Measured value: 672.2427

[0209] Example 45 Synthesis of Compound 7Td 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 17 of the present invention) Compound 7Tc (1.73 g, 2.66 mmol), dichloromethane (13 mL), and DIPEA (1.39 mL, 7.98 mmol) were mixed together, and 2-cyanoethyl N,N-diisopropyl chlorophosphoramimide (1.19 mL, 5.32 mmol) was added to the mixture under ice cooling. The mixture was stirred overnight at room temperature under a nitrogen atmosphere. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator, and the solvent was removed under reduced pressure. The residue was then subjected to column chromatography (SiO₂). ２ The compound was purified using the following methods: hexane / ethyl acetate = 60 / 40 to 10 / 90, Diol: hexane / ethyl acetate = 70 / 30 to 20 / 80, NH: chloroform / methanol = 100 / 0 to 95 / 5) to obtain compound 7Td (1.53 g, yield 68%) as compound 17 of the present invention. HRMS(FAB): C ４５ H ５２ N ７ O ８ Calculated value at P [M+H] + : 850.3693, Measured value: 850.3699 31 P-NMR (CDCl3) δ: 148.72, 148.83

[0210] Synthesis of ALNA[2Pym]-mC

[0211] Example 46 Synthesis of Compound 7mCa [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 7Ta (3.68 g, 5.67 mmol), DMAP (69.3 mg, 0.567 mmol), and pyridine (28 mL) was mixed with acetic anhydride (0.804 mL, 8.51 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. Pyridine was azeotropically deconjugated with ethyl acetate, followed by trituration with diisopropyl ether to obtain 7 mCa of compound (3.49 g, 89% yield). HRMS(FAB): C ３８ H ３８ N ５ O ８ Calculated value [M+H]+: 692.2720, Measured value: 692.2713

[0212] Example 47 Synthesis of Compound 7mCb [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-[5-methyl-2-oxo-4-(1,2,4-triazole-1-yl)pyrimidine-1-yl]-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 7mCa (3.46 g, 5.00 mmol), 1,2,4-triazole (3.11 g, 45.0 mmol), DIPEA (8.71 mL, 50.0 mmol), and acetonitrile (50 mL) were mixed together, and phosphorus oxychloride (0.792 mL, 8.50 mmol) was added under ice cooling. The mixture was stirred overnight at room temperature under a nitrogen atmosphere. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. Trituration with diisopropyl ether yielded compound 7mCb1 (3.40 g, 92% yield). HRMS(FAB): C ４０ H ３８ N ８O ７ Calculated value [M+H] + : 743.2942, Measured value: 743.2945

[0213] Example 48 Synthesis of Compound 7mCc 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 7mCb (3.40 g, 4.58 mmol) and acetonitrile (46 mL) was mixed with 28% aqueous ammonia (31 mL), and the mixture was stirred at room temperature for 3 days. Water was added to the reaction mixture and extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. It was triturated with diisopropyl ether and a small amount of ethyl acetate to obtain Compound 7mCc (2.65 g, yield 89%). HRMS(FAB): C ３６ H ３６ N ６ O ６ Calculated value [M+H] + : 649.2775, Measured value: 649.2766

[0214] Example 49 Synthesis of Compound 7mCd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 7mCc (2.62 g, 4.04 mmol) and DMF (20 mL) were mixed with benzoic anhydride (959 mg, 4.24 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. The residue was analyzed by column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 7mCd (1.42 g, 47% yield). HRMS(FAB): C ４３ H４０ N ６ O ７ Calculated value [M+H] + :753.3037, Measured value: 753.3035

[0215] Example 50 Synthesis of Compound 7mCe N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 18 of the present invention) A mixture of Compound 7mCd (1.40 g, 1.86 mmol), dichloromethane (9 mL), and DIPEA (0.972 mL, 5.58 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (0.830 mL, 3.72 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using hexane / ethyl acetate (80 / 20 to 30 / 70, NH:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 7mCe (1.01 g, yield 57%) as compound 18 of the present invention. HRMS(FAB): C ５２ H ５７ N ８ O ８ Calculated value at P [M+Na] + : 975.3935, Measured value: 975.3931 31 P-NMR (CDCl3) δ: 149.17, 149.23

[0216] Synthesis of ALNA[2Pym]-G

[0217] Example 51 Synthesis of Compound 7Gc N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-formamidine 28% aqueous ammonia (40 mL) was added to a solution of Compound 1d (3.00 g, 3.50 mmol) in methanol (20 mL) and THF (20 mL). The mixture was left to stand at room temperature for 16 hours after adding methanol (20 mL) and THF (20 mL). A methanol solution of 40% methylamine (40 mL) was added and the mixture was left to stand at room temperature for 4 hours. After removing the solvent by distillation, the mixture was azeotropically mixed with toluene and dried under reduced pressure. The residue was dissolved in DMSO (35 mL), then DIPEA (4.8 mL, 28.0 mmol) and 2-fluoropyrimidine (0.66 mL, 10.5 mmol) were added, and the mixture was stirred at 80°C for 2 hours, followed by stirring at 100°C for 2 hours. Another 2-fluoropyrimidine (0.66 mL, 10.5 mmol) was added, and the mixture was stirred again at 100°C for 2 hours. 2-fluoropyrimidine (0.22 mL, 3.5 mmol) and DIPEA (1.6 mL, 9.3 mmol) were added again, and the mixture was stirred at 100°C for 2 hours. N,N-dimethylformamide dimethylacetal (2.3 mL, 17.0 mmol) was added to the reaction mixture and stirred at room temperature. After 1 hour, ethyl acetate (200 mL), saturated sodium bicarbonate solution (20 mL), and water (80 mL) were added and the mixture was separated. The organic layer was washed three times with water (50 mL), followed by washing with saturated brine. After drying with sodium sulfate, insoluble matter was filtered off and the solvent was removed under reduced pressure. The aqueous layer obtained from liquid-liquid extraction was then extracted three times with chloroform (100 mL), and washed with water (100 mL) and saturated saline solution. After drying the chloroform layer with sodium sulfate, insoluble matter was filtered off and the solvent was removed under reduced pressure. The mixture was then purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 92 / 8) to obtain compound 7 Gc (1.66 g, 65% yield in 3 steps). MS (ESI): m / z = 731 (M + H) +

[0218] Example 52 Synthesis of Compound 7Gd N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-6-formamidine (Inventive Compound 19) Compound 7Gd (1.07 g, yield 53%) as Inventive Compound 19 was obtained from Compound 7Gc (1.58 g, 2.16 mmol) in the same manner as in Example 4. MS (ESI): m / z = 931 (M + H) +

[0219] Synthesis of ALNA[2Pym]-A

[0220] Example 53 Synthesis of Compound 7Aa N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide A mixture of Compound 1e (500 mg, 0.730 mmol) synthesized by the method described in International Publication No. 2017 / 047816, 2-fluoropyrimidine (215 mg, 2.19 mmol), DIPEA (0.509 mL, 2.92 mmol), and DMSO (7 mL) was stirred at 130°C under a nitrogen atmosphere for 7 hours. Ethyl acetate was added to the reaction mixture and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the solvent was removed under reduced pressure and concentrated. The residue was analyzed by column chromatography (SiO ２ The compound was purified using hexane / ethyl acetate (50 / 50 to 0 / 100) to obtain compound 7Aa (207 mg, 37% yield). HRMS(MALDI): C ４３ H ３８ N ８ O ６ Calculated value [M+Na] + : 785.2807, Measured value: 785.2807

[0221] Example 54 Synthesis of Compound 7Ab N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (Compound 20 of the present invention) Compound 7Aa (126 mg, 0.165 mmol), dichloromethane (3 mL), and DIPEA (86.2 μL, 0.495 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (73.6 μL, 0.330 mmol), and the mixture was stirred at room temperature under a nitrogen atmosphere for 5 hours. Saturated sodium bicarbonate aqueous solution was added to the reaction solution and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (NH:hexane / ethyl acetate = 50 / 50 to 0 / 100, SiO₂). ２ The compound was purified using a diol-hexane / ethyl acetate solution (50 / 50 to 0 / 100, hexane / ethyl acetate solution (60 / 40 to 10 / 90)) to obtain compound 7Ab (110 mg, 69% yield) as compound 20 of the present invention. HRMS(MALDI): C ５２ H ５５ N １０ O ７ Calculated value at P [M+Na] + : 985.3885, Measured value: 985.3878 31 P-NMR (CDCl3) δ: 149.33, 149.47

[0222] Synthesis of ALNA[4Pym]-T

[0223] Example 55 Synthesis of Compound 8Ta 1-[(1R,3R,4R,7S)-7-benzyloxy-1-(benzyloxymethyl)-5-(6-chloropyrimidine-4-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 1f (1.00 g, 2.22 mmol), synthesized by the method described in International Publication No. 2017 / 047816, 4,6-dichloropyrimidine (398 mg, 2.66 mmol), DIPEA (1.16 mL, 6.66 mmol), and EtOH (20 mL) were mixed (2 batches) and stirred separately for 5 hours at 120°C under microwave irradiation. The batches were combined, insoluble matter from the reaction solution was filtered off, and the mixture was washed with EtOH to obtain Compound 8Ta (1.54 g, yield 62%). HRMS(FAB): C ２９ H ２８ ClN ５ O ５ Calculated value [M+H] + : 562.1857, Measured value: 562.1859

[0224] Example 56 Synthesis of Compound 8Tb 1-[(1R,3R,4R,7S)-5-(6-chloropyrimidine-4-yl)-7-hydroxy-1-(hydroxymethyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 8Ta (3.49 g, 6.21 mmol) and dichloromethane (62 mL) was mixed with trichloroborane (1.0 mol / L dichloromethane solution, 62 mL, 62.1 mmol) under a nitrogen atmosphere at -78°C, and the mixture was stirred overnight while gradually raising the temperature to room temperature. Under ice cooling, MeOH (62 mL) was slowly added to the reaction mixture and stirred for a while at room temperature. After concentrating the reaction mixture, it was triturated with ethyl acetate to obtain Compound 8Tb (3.27 g) as the crude product. HRMS(FAB): C １５ H １６ ClN ５ O ５ Calculated value [M+H] + : 382.0918, Measured value: 382.0919

[0225] Example 57 Synthesis of Compound 8Tc 1-[(1R,3R,4R,7S)-7-hydroxy-1-(hydroxymethyl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione Compound 8Tb (3.27 g, 6.21 mmol, crude) and MeOH (62 mL) were mixed with 20% palladium hydroxide (654 mg, 20 wt%), and the mixture was stirred overnight at room temperature under a hydrogen atmosphere. Water (31 mL) was added to the reaction mixture to dissolve the insoluble matter, and the palladium was filtered off using Celite. The filtrate was concentrated, and the water was azeotropically dissolved with toluene. The residue was triturated with MeOH to obtain Compound 8Tc (1.75 g, 81% yield in 2 steps). HRMS(MALDI): C １５ H １７ N ５ O ５ Calculated value [M+H] + : 348.1302, Measured value: 348.1308

[0226] Example 58 Synthesis of Compound 8Td 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 8Tc (444 mg, 1.28 mmol) and pyridine (13 mL) was mixed with 4,4-dimethoxytrityl chloride (520 mg, 1.54 mmol), and the mixture was stirred overnight at room temperature. Under ice cooling, the reaction mixture was added dropwise to saturated sodium bicarbonate aqueous solution, and ethyl acetate was added thereto. The organic layer was washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Pyridine was removed azeotropically with ethyl acetate, and the residue was triturated with diisopropyl ether to obtain compound 8Td (652 mg, 78% yield). HRMS(MALDI): C ３６ H ３５ N ５ O ７ Calculated value [M+H] + : 650.2609, Measured value: 650.2600

[0227] Example 59 Synthesis of Compound 8Te 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 21 of the present invention) A mixture of Compound 8Td (300 mg, 0.462 mmol), dichloromethane (5 mL), and DIPEA (322 μL, 1.85 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoramide (309 μL, 1.39 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound 8Te (263 mg, 67% yield) was purified using chloroform / methanol (100 / 0 to 90 / 10) and diol (hexane / ethyl acetate (50 / 50 to 0 / 100) to obtain compound 8Te as compound 21 of the present invention. HRMS(FAB): C ４５ H ５２ N ７ O ８ Calculated value at P [M+H] + : 850.3693, Measured value: 850.3685 31 P-NMR (CDCl3) δ: 148.93, 149.47

[0228] Synthesis of ALNA[4Pym]-mC

[0229] Example 60 Synthesis of Compound 8Ca [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 8Td (234 mg, 0.360 mmol), DMAP (4.4 mg, 0.0360 mmol), and pyridine (3.6 mL) was mixed with acetic anhydride (51.1 μL, 0.540 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with 5% copper sulfate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was triturated with diisopropyl ether to obtain Compound 8Ca (219 mg, yield 88%). HRMS(FAB): C ３８ H ３７ N ５ O ８ Calculated value [M+H] + : 692.2720, Measured value: 692.2720

[0230] Example 61 Synthesis of Compound 8Cb [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-[5-methyl-2-oxo-4-(1,2,4-triazole-1-yl)pyrimidine-1-yl)-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 8Ca (201 mg, 0.291 mmol), 1,2,4-triazole (181 mg, 2.62 mmol), DIPEA (507 μL, 2.91 mmol), and acetonitrile (3 mL) were mixed with phosphorus oxychloride (46.1 μL, 0.494 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Trituration with diisopropyl ether yielded compound 8Cb (211 mg, 98% yield). HRMS(FAB): C ４０ H ３８ N ８ O ７ Calculated value [M+H]+ : 743.2942, Measured value: 743.2939

[0231] Example 62 Synthesis of Compound 8Cc 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 8Cb (613 mg, 0.825 mmol) and acetonitrile (8.3 mL) was mixed with 28% aqueous ammonia (5.5 mL), and the mixture was stirred overnight at room temperature. The acetonitrile of the reaction solution was concentrated. Insoluble matter was filtered off and washed with water. The crude product was triturated again with ethyl acetate to obtain Compound 8Cc (380 mg, yield 71%). HRMS(FAB): C ３６ H ３６ N ６ O ６ Calculated value [M+H] + : 649.2775, Measured value: 649.2773

[0232] Example 63 Synthesis of Compound 8Cd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide A mixture of Compound 8Cc (378 mg, 0.583 mmol) and pyridine (6 mL) was mixed with benzoic anhydride (198 mg, 0.875 mmol), and the mixture was stirred at room temperature for 3 days. The reaction mixture was concentrated, and the residue was subjected to column chromatography (diol: 0.5% triethylamine-chloroform / methanol = 100 / 0 to 90 / 10, SiO ２ The compound 8Cd (247 mg, 56% yield) was obtained by purification using 0.5% triethylamine-chloroform / methanol (100 / 0 to 90 / 10). HRMS(FAB): C ４３ H ４０ N ６ O ７ Calculated value [M+H] +: 753.3037, Measured value: 753.3040

[0233] Example 64 Synthesis of Compound 8Ce N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidine-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 22 of the present invention) Compound 8Cd (135 mg, 0.179 mmol), dichloromethane (2 mL), and DIPEA (125 μL, 0.716 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (120 μL, 0.537 mmol), and the mixture was stirred at room temperature under a nitrogen atmosphere for 2 days. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using the following methods: hexane / ethyl acetate = 50 / 50 to 0 / 100 (for diols: hexane / ethyl acetate = 60 / 40 to 10 / 90, for NH: hexane / ethyl acetate = 50 / 50 to 0 / 100) to obtain compound 8Ce (61.9 mg, 36% yield) as compound 22 of the present invention. HRMS(FAB): C ５２ H ５７ N ８ O ８ Calculated value at P [M+H] + : 953.4115, Measured value: 953.4109 31 P-NMR (CDCl3) δ: 149.65, 150.24

[0234] ALNA [4-CF] ３ Synthesis of -2Pym]-T

[0235] Example 65 Synthesis of Compound 9Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (500 mg, 0.875 mmol), 2-chloro-4-trifluoropyrimidine (239 mg, 1.31 mmol), DIPEA (457 μL, 2.63 mmol), and EtOH (4.4 mL) was stirred at 120°C for 30 minutes under microwave irradiation. 2-chloro-4-trifluoropyrimidine (239 mg, 1.31 mmol) and DIPEA (457 μL, 2.63 mmol) were added to the reaction mixture, and the mixture was stirred at 120°C for 1 hour under microwave irradiation. The reaction mixture was concentrated, ethyl acetate was added, and it was washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO₂). ２ The compound 9Ta (545 mg, 87% yield) was obtained by purification using chloroform / methanol (100 / 0 to 95 / 5). HRMS(FAB): C ３７ H ３４ F ３ N ５ O ７ Calculated value [M+H] + : 718.2489, Measured value: 718.2491

[0236] Example 66 Synthesis of Compound 9Tb 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 23 of the present invention) A mixture of Compound 9Ta (527 mg, 0.734 mmol), dichloromethane (7 mL), and DIPEA (384 μL, 2.20 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (328 μL, 1.47 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound 9Tb (530 mg, 79% yield) was purified using hexane / ethyl acetate (80 / 20-30 / 70, diol: hexane / ethyl acetate = 70 / 30-20 / 80) as compound 23 of the present invention. HRMS(FAB): C ４６ H ５１ F ３ N ７ O ８ Calculated value at P [M+H] + : 918.3567, Measured value: 918.3568 31 P-NMR (CDCl3) δ: 149.04, 149.12, 149.20, 149.47

[0237] ALNA [4-CF] ３ Synthesis of -2Pym]-G

[0238] Example 67 Synthesis of Compound 9Ca 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 4Ca (500 mg, 0.876 mmol), 2-chloro-4-trifluoropyrimidine (317 μL, 2.63 mmol), DIPEA (610 μL, 3.50 mmol), and EtOH (4.4 mL) was stirred at 150°C for 1 hour under microwave irradiation. The reaction mixture was concentrated, ethyl acetate was added, and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO2 ２ The compound 9Ca (186 mg, 30% yield) was obtained by purification using chloroform / methanol (100 / 0 to 90 / 10). HRMS(FAB): C ３７ H ３５ F ３ N ６ O ６ Calculated value [M+H] + : 717.2648, Measured value: 717.2651

[0239] Example 68 Synthesis of Compound 9Cb N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 9Ca (395 mg, 0.551 mmol) and DMF (5.5 mL) were mixed with benzoic anhydride (131 mg, 0.579 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 15) to obtain compound 9Cb (335 mg, 74% yield). HRMS(FAB): C４４ H ３９ F ３ N ６ O ７ Calculated value [M+H] + : 821.2911, Measured value: 821.2932

[0240] Example 69 Synthesis of Compound 9Cc N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanethoxy-(diisopropylamino)phosphanyl]oxy-5-[4-(trifluoromethyl)pyrimidine-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 24 of the present invention) Compound 9Cb (316 mg, 0.385 mmol), dichloromethane (4 mL), and DIPEA (201 μL, 1.16 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (172 μL, 0.770 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound 9Cc (227 mg, 58% yield) was purified using hexane / ethyl acetate (100 / 0 to 50 / 50, Diol:hexane / ethyl acetate = 100 / 0 to 50 / 50) as compound 24 of the present invention. HRMS(FAB): C ５３ H ５６ F ３ N ８ O ８ Calculated value at P [M+H] + : 1021.3989, Measured value: 1021.3993 31 P-NMR (CDCl3) δ: 149.15, 149.28, 149.36, 149.60

[0241] Synthesis of ALNA[5-Cl-2Pym]-G

[0242] Example 70 Synthesis of Compound 10Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (500 mg, 0.875 mmol), 2,5-dichloropyrimidine (196 mg, 1.31 mmol), DIPEA (457 μL, 2.63 mmol), and EtOH (4.4 mL) was stirred at 150°C for 1 hour under microwave irradiation. Insoluble matter in the reaction mixture was dissolved with chloroform and concentrated. The residue was subjected to column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 10Ta (263 mg, 44% yield). HRMS(FAB): C ３６ H ３４ ClN ５ O ７ Calculated value [M+H] + : 684.2225, Measured value: 684.2226

[0243] Example 71 Synthesis of Compound 10Tb 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 25 of the present invention) A mixture of Compound 10Ta (240 mg, 0.351 mmol), dichloromethane (3.5 mL), and DIPEA (183 μL, 1.05 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (157 μL, 0.702 mmol) under ice cooling, and the mixture was stirred at room temperature under a nitrogen atmosphere for 4 days. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２The compound was purified using hexane / ethyl acetate (70 / 30 to 20 / 80, diol: hexane / ethyl acetate (70 / 30 to 20 / 80)) to obtain compound 10Tb (201 mg, yield 65%) as compound 25 of the present invention. HRMS(FAB): C ４５ H ５１ ClN ７ O ８ Calculated value at P [M+H] + : 884.3304, Measured value: 884.3303 31 P-NMR (CDCl3) δ: 149.12

[0244] Synthesis of ALNA[5-Cl-2Pym]-mC

[0245] Example 72 Synthesis of Compound 10mCa 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 4Ca (500 mg, 0.876 mmol), 2,5-dichloropyrimidine (391 mg, 2.63 mmol), DIPEA (610 μL, 3.50 mmol), and EtOH (4.4 mL) (2 batches) was stirred at 150°C for 1 hour under microwave irradiation for each batch. The reaction mixture was concentrated, water was added, and extracted with chloroform. The combined organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain 10 mCa (381 mg, 32% yield). HRMS(FAB): C ３６ H ３５ ClN ６ O ６ Calculated value [M+H] + : 683.2385, Measured value: 683.2389

[0246] Example 73 Synthesis of Compound 10mCb N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide A mixture of Compound 10mCa (375 mg, 0.549 mmol) and DMF (5.5 mL) was mixed with benzoic anhydride (130 mg, 0.576 mmol), and the mixture was stirred overnight at room temperature. Benzoic anhydride (24.8 mg, 0.110 mmol) was added to the reaction mixture and stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Residual column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain 10 mCb of compound (422 mg, 98% yield). HRMS(MALDI): C ４３ H ３９ ClN ６ O ７ Calculated value [M+Na] + : 809.2461, Measured value: 809.2463

[0247] Example 74 Synthesis of Compound 10 mCc N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidine-2-yl)-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-pyrimidine-4-yl]benzamide (Compound 26 of the present invention) Compound 10 mCb (409 mg, 0.520 mmol), dichloromethane (5 mL), and DIPEA (272 μL, 1.56 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (232 μL, 1.04 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using hexane / ethyl acetate (100 / 0 to 50 / 50, diol: hexane / ethyl acetate (100 / 0 to 50 / 50)) to obtain compound 10 mCc (264 mg, yield 51%) as compound 26 of the present invention. HRMS(MALDI): C ５２ H ５６ ClN ８ O ８ Calculated value at P [M+Na] + : 1009.3540, Measured value: 1009.3521 31 P-NMR (CDCl3) δ: 149.28

[0248] ALNA[6-NMe ２ Synthesis of -4Pym]-T

[0249] Example 75 Synthesis of Compound 11Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(6-chloropyrimidine-4-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (1.00 g, 1.75 mmol), 4,6-2-dichloropyrimidine (391 mg, 2.63 mmol), DIPEA (914 μL, 5.25 mmol), and EtOH (18 mL) was stirred at 120°C under microwave irradiation for 1 hour. The reaction mixture was concentrated and the residue was subjected to column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain compound 11Ta (1.00 g, yield 84%). HRMS(FAB): C ３６ H ３４ ClN ５ O ７ Calculated value [M+H] + : 684.2225, Measured value: 684.2214

[0250] Example 76 Synthesis of Compound 11Tb 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 11Ta (500 mg, 0.731 mmol), DIPEA (637 μL, 3.66 mmol), and EtOH (5 mL) was mixed with dimethylamine hydrochloride (179 mg, 2.19 mmol) and stirred at 150°C for 30 minutes under microwave irradiation. Compound 11Tb (386 mg, yield 76%) was obtained by filtering off the insoluble material. HRMS(FAB): C ３８ H ４０ N ６ O ７ Calculated value [M+H] + : 693.3037, Measured value: 693.3030

[0251] Example 77 Synthesis of Compound 11Tc 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamine)phosphanyl]oxypropanenitrile (Compound 27 of the present invention) A mixture of Compound 11Tb (335 mg, 0.484 mmol), dichloromethane (5 mL), and DIPEA (253 μL, 1.45 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (216 μL, 0.968 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Add 2 mL of DMF to the reaction mixture and stir overnight at room temperature under a nitrogen atmosphere. Add 253 μL, 1.45 mmol of DIPEA and 216 μL, 0.968 mmol of 2-cyanoethyl N,N-diisopropyl chlorophosphoramide to the reaction mixture and stir the mixture at room temperature under a nitrogen atmosphere for 2 days. Add ethyl acetate to the reaction mixture and wash with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10, Diol:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 11Tc (189 mg, 44% yield) as compound 27 of the present invention. HRMS(FAB): C ４７ H ５７ N ８ O ８ Calculated value at P [M+H] + : 893.4115, Measured value: 893.4115 31 P-NMR (CDCl3) δ: 148.83, 148.99

[0252] ALNA[6-NMe ２ Synthesis of -4Pym]-mC

[0253] Example 78 Synthesis of Compound 11mCa 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(6-chloropyrimidine-4-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 4mCa1 (2.00 g, 3.50 mmol), 4,6-dichloropyrimidine (626 mg, 4.20 mmol), DIPEA (1.83 mL, 10.5 mmol), and EtOH (17.5 mL) was stirred at 100°C for 4 hours. The reaction mixture was concentrated, water was added, and it was extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO2 ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain 11 mCa (1.34 g, 56% yield). HRMS(FAB): C ３６ H ３５ ClN ６ O ６ Calculated value [M+H] + : 683.2385, Measured value: 683.2384

[0254] Example 79 Synthesis of Compound 11mCb 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 11mCa (1.12 g, 1.64 mmol), dimethylamine (50% aqueous solution, 863 μL, 8.20 mmol), and EtOH (11 mL) was stirred at 150°C for 30 minutes under microwave irradiation. The reaction mixture was concentrated, and the residue was purified by column chromatography (NH: chloroform / methanol = 100 / 0 to 95 / 5) to obtain Compound 11mCb (1.09 g, yield 96%). HRMS(MALDI): C ３８ H ４１ N ７ O ６ Calculated value [M+Na] +: 714.3011, Measured value: 714.3003

[0255] Example 80 Synthesis of Compound 11mCc N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide A mixture of Compound 11mCb (1.08 g, 1.56 mmol) and DMF (8 mL) was mixed with benzoic anhydride (389 mg, 1.72 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO2). ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain 11 mCc (1.02 g, yield 82%). HRMS(MALDI): C ４５ H ４５ N ７ O ７ Calculated value [M+H] + : 796.3453, Measured value: 796.3466

[0256] Example 81 Synthesis of Compound 11mCd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanothoxy-(diisopropylamino)phosphanyl]oxy-5-[(6-dimethylamino)pyrimidine-4-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 28 of the present invention) Compound 11mCc (972 mg, 1.22 mmol), dichloromethane (12 mL), and DIPEA (637 μL, 3.66 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (545 μL, 2.44 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using hexane / ethyl acetate (50 / 50 to 0 / 100, NH:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 11mCd (788 mg, yield 65%) as compound 28 of the present invention. HRMS(MALDI): C ５４ H ６２ N ９ O ８ Calculated value at P [M+H] + : 996.4532, Measured value: 996.4513 31 P-NMR (CDCl3) δ: 149.06, 149.17

[0257] ALNA[2-NMe ２ Synthesis of -4Pym]-T

[0258] Example 82 Synthesis of Compound 12Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(2-chloropyrimidine-4-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (2.00 g, 3.50 mmol), 2,4-dichloropyrimidine (782 mg, 5.25 mmol), DIPEA (1.83 mL, 10.5 mmol), and EtOH (17.5 mL) was stirred at 100°C for 4.5 hours. The reaction mixture was concentrated, water was added, and it was extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain compound 12Ta (1.86 g, 78% yield). HRMS(FAB): C ３６ H ３４ ClN ５ O ７ Calculated value [M+H] + : 684.2225, Measured value: 684.2223

[0259] Example 83 Synthesis of Compound 12Tb 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 12Ta (500 mg, 0.731 mmol), DIPEA (637 μL, 3.66 mmol), and EtOH (5 mL) was mixed with dimethylamine hydrochloride (179 mg, 2.19 mmol) and stirred at 150°C under microwave irradiation for 30 minutes. The reaction mixture was concentrated and the residue was subjected to column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5). Tritylation with diisopropyl ether was performed to obtain compound 12Tb (648 mg) as the crude product. HRMS(FAB): C ３８ H ４０ N ６ O ７Calculated value [M+H] + : 693.3037, Measured value: 693.3041

[0260] Example 84 Synthesis of Compound 12Tc 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)oxypropanenitrile (Compound 29 of the present invention) A mixture of Compound 12Tb (638 mg, 0.731 mmol, crude), dichloromethane (7 mL), and DIPEA (382 μL, 2.19 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (326 μL, 1.46 mmol) under ice cooling, and the mixture was stirred at room temperature under a nitrogen atmosphere for 5 days. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10, diol: hexane / ethyl acetate (50 / 50 to 0 / 100) to obtain compound 12Tc (304 mg, 47% yield in two steps) as compound 29 of the present invention. HRMS(FAB): C ４７ H ５７ N ８ O ８ Calculated value at P [M+H] + : 893.4115, Measured value: 893.4128 31 P-NMR (CDCl3) δ: 148.91, 149.33

[0261] ALNA[2-NMe ２ Synthesis of -4Pym]-mC

[0262] Example 85 Synthesis of Compound 12mCa 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(2-chloropyrimidine-4-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of 4mCa compound (2.00g, 3.50 mmol), 2,4-dichloropyrimidine (627mg, 4.20 mmol), DIPEA (1.83mL, 10.5 mmol), and EtOH (17.5mL) was stirred at 100°C for 3 hours. The reaction mixture was concentrated, water was added, and it was extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO2 ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain 12 mCa (1.28 g, 54% yield). HRMS (MALDI): C ３６ H ３５ ClN ６ O ６ Calculated value [M+Na] + : 705.2199, Measured value: 705.2194

[0263] Example 86 Synthesis of Compound 12mCb 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 12mCa (941 mg, 1.38 mmol), dimethylamine (50% aqueous solution, 725 μL, 6.90 mmol), and EtOH (14 mL, 0.1 M) was stirred at 150°C for 30 minutes under microwave irradiation. The reaction mixture was concentrated, and the residue was purified by column chromatography (NH: chloroform / methanol = 100 / 0 to 90 / 10) to obtain Compound 12mCb (784 mg, yield 82%). HRMS(MALDI): C ３８ H ４１ N ７ O ６ Calculated value [M+H] +: 692.3191, Measured value: 692.3167

[0264] Example 87 Synthesis of Compound 12mCc N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 12mCb (754 mg, 1.09 mmol) and DMF (5.5 mL) were mixed with benzoic anhydride (271 mg, 1.20 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain 12 mCc of the compound (731 mg, yield 84%). HRMS(MALDI): C ４５ H ４５ N ７ O ７ Calculated value [M+H] + :796.3453, Measured value: 796.3440

[0265] Example 88 Synthesis of Compound 12mCd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-[2-(dimethylamino)pyrimidine-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 30 of the present invention) Compound 12mCc (709 mg, 0.891 mmol), dichloromethane (9 mL), and DIPEA (466 μL, 2.67 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (397 μL, 1.78 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using hexane / ethyl acetate (50 / 50 to 0 / 100, NH:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 12mCd (482 mg, yield 54%) as compound 30 of the present invention. HRMS(MALDI): C ５４ H ６２ N ９ O ８ Calculated value at P [M+H] + : 996.4532, Measured value: 996.4526 31 P-NMR (CDCl3) δ: 149.19, 149.46, 149.65

[0266] Synthesis of ALNA[Prz]-T

[0267] Example 89 Synthesis of Compound 13Ta [1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (500 mg, 0.875 mmol), 2-fluoropyrazine (201 μL, 2.63 mmol), DIPEA (610 μL, 3.50 mmol), and DMSO (8.8 mL) was stirred under a nitrogen atmosphere at 140°C for 1.5 hours and then at 150°C for 4.5 hours. Ethyl acetate was added to the reaction mixture and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO ２ : Chloroform / methanol = 100 / 0 to 90 / 10, SiO ２ The compound was purified using hexane / ethyl acetate (50 / 50 to 0 / 100) to obtain compound 13Ta (227 mg, 40% yield). HRMS(MALDI): C ３６ H ３５ N ５ O ７ Calculated value [M+Na] + : 672.2429, Measured value: 672.2409

[0268] Example 90 Synthesis of Compound 13Tb 3-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 31 of the present invention) A mixture of Compound 13Ta (214 mg, 0.329 mmol), dichloromethane (6.6 mL), and DIPEA (172 μL, 0.987 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (147 μL, 0.658 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated aqueous sodium bicarbonate solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂).２ The compound was purified using hexane / ethyl acetate (50 / 50 to 0 / 100, NH:ethyl acetate / methanol (100 / 0 to 90 / 10)) to obtain compound 13Tb (204 mg, 73% yield) as compound 31 of the present invention. HRMS(MALDI): C ４５ H ５２ N ７ O ８ Calculated value at P [M+Na] + : 872.3507, Measured value: 872.3507 31 P-NMR (CDCl3) δ: 149.12, 149.31

[0269] Synthesis of ALNA[Prz]-mC

[0270] Example 91 Synthesis of Compound 13mCb [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 13Ta (746 mg, 1.15 mmol), DMAP (14.0 mg, 0.115 mmol), and pyridine (5.8 mL) was mixed with acetic anhydride (163 μL, 1.73 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. Pyridine was removed azeotropically with ethyl acetate, and the residue was triturated with diisopropyl ether to obtain compound 13 mCb (712 mg, 90% yield). HRMS(MALDI): C ３８ H ３７ N ５ O ８ Calculated value [M+Na] + : 714.2534, Measured value: 714.2520

[0271] Example 92 Synthesis of Compound 13mCc [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2-oxo-(4-1,2,4-triazole-1-yl)pyrimidine-1-yl]-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of compound 13mCb (692 mg, 1.00 mmol), 1,2,4-triazole (622 mg, 9.00 mmol), DIPEA (1.74 mL, 10.0 mmol), and acetonitrile (10 mL) was mixed with phosphorus oxychloride (158 μL, 1.70 mmol) under ice cooling, and the mixture was stirred at room temperature under a nitrogen atmosphere for 1 hour. Ethyl acetate was added to the reaction mixture, and it was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated to obtain compound 13mCc (753 mg) as the crude product. HRMS(MALDI): C ４０ H ３８ N ８ O ７ Calculated value [M+Na] + : 765.2756, Measured value: 765.2750

[0272] Example 93 Synthesis of Compound 13mCd 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Compound 13mCc (744 mg, 1.00 mmol, crude) and acetonitrile (10 mL) were mixed with 28% aqueous ammonia (6.7 mL), and the mixture was stirred overnight at room temperature. Water was added to the reaction mixture and extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate and concentrated to obtain Compound 13mCd (638 mg, yield 98%, 2 steps). HRMS(MALDI): C ３６ H ３６ N ６ O ６ Calculated value [M+Na] + : 671.2589, Measured value: 671.2591

[0273] Example 94 Synthesis of Compound 13mCe N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 13mCd (625 mg, 0.963 mmol) and DMF (4.8 mL) were mixed with benzoic anhydride (327 mg, 1.44 mmol) and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate and concentrated. The residue was analyzed by column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain compound 13mCe (245 mg, 34% yield). HRMS(MALDI): C ４３ H ４０ N ６ O ７ Calculated value [M+Na] + : 775.2851, Measured value: 775.2845

[0274] Example 95 Synthesis of Compound 13mCf N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrazine-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 32 of the present invention) A mixture of Compound 13mCe (565 mg, 0.751 mmol), dichloromethane (7.5 mL), and DIPEA (392 μL, 2.25 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (335 μL, 1.50 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２The compound was purified using hexane / ethyl acetate (70 / 30 to 20 / 80, NH:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 13 mCf (369 mg, yield 52%) as compound 32 of the present invention. HRMS(MALDI): C ５０ H ４４ N ６ O ８ Calculated value [M+Na] + : 975.3929, Measured value: 975.3923 31 P-NMR (CDCl3) δ: 149.25, 149.49

[0275] Synthesis of ALNA[Trz]-T

[0276] Example 96 Synthesis of Compound 14Ta (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carbothioamide A mixture of Compound 1a (2.00 g, 3.50 mmol) and THF (17.5 mL) was mixed with 1,1-thiocarbonyldiimidazole (1.25 g, 7.00 mmol), and the mixture was stirred overnight at room temperature. 28% aqueous ammonia (17.5 mL) was added to the reaction mixture and stirred overnight at room temperature. The reaction mixture was concentrated, and the insoluble material was filtered off. By washing the insoluble material with water, Compound 14Ta (2.35 g) was obtained as crude. HRMS(MALDI): C ３３ H ３４ N ４ O ７ Calculated value [M+Na] + : 653.2040, Measured value: 653.2026

[0277] Example 97 Synthesis of Compound 14Tb Methyl (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboxymidothioate A mixture of Compound 14Ta (2.35 g, 3.50 mmol, crude) and THF (17.5 mL) was mixed with methyl iodide (654 μL, 10.5 mmol), and the mixture was stirred at room temperature for 2 days. Saturated aqueous sodium bicarbonate solution was added to the reaction mixture and extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. The residue was analyzed by column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 80 / 20) to obtain compound 14Tb (1.88 g, 83% yield in two steps). HRMS(MALDI): C ３４ H ３６ N ４ O ７ Calculated value [M+H] + : 645.2377, Measured value: 645.2374

[0278] Example 98 Synthesis of Compound 14Tc [(1R,3R,4R,7S)-5-[(Z)-N-acetyl-C-methylsulfanyl-carboimidyl]-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 14Tb (1.87 g, 2.90 mmol), DMAP (35.4 mg, 0.290 mmol), and pyridine (14.5 mL) were mixed with acetic anhydride (822 μL, 8.70 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with 5% copper sulfate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure to obtain compound 14Tc (2.11 g, 100% yield). HRMS(MALDI): C ３８ H ４０ N ４ O ９Calculated value [M+Na]+ in S: 751.2408, Measured value: 751.2398

[0279] Example 99 Synthesis of Compound 14Td 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 14Tc (1.66 g, 2.28 mmol) and EtOH (23 mL) was mixed with methylhydrazine (1.20 mL, 22.8 mmol), and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated, and the residue was subjected to column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 14Td (985 mg, 65% yield). HRMS(MALDI): C ３６ H ３８ N ６ O ７ Calculated value [M+Na] + : 689.2694, Measured value: 689.2684

[0280] Example 100 Synthesis of Compound 14Te 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 33 of the present invention) Compound 14Td (576 mg, 0.864 mmol), dichloromethane (8.6 mL), and DIPEA (451 μL, 2.59 mmol) were mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (385 μL, 1.73 mmol), and the mixture was stirred at room temperature under a nitrogen atmosphere for 2 days. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２The compound 14Te (517 mg, 69% yield) was purified using a diol (hexane / ethyl acetate = 50 / 50 to 0 / 100, diol: hexane / ethyl acetate = 50 / 50 to 0 / 100) as compound 33 of the present invention. HRMS(MALDI): C ４５ H ５５ N ８ O ８ Calculated value at P [M+Na] + :889.3773, Measured value: 889.3778 31 P-NMR (CDCl3) δ: 148.40, 148.45

[0281] Synthesis of ALNA[Trz]-mC

[0282] Example 101 Synthesis of Compound 14Ca [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 14Td (918 mg, 1.38 mmol), DMAP (16.9 mg, 0.138 mmol), and pyridine (6.9 mL) was mixed with acetic anhydride (196 μL, 2.07 mmol), and the mixture was stirred overnight at room temperature. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure to obtain compound 14Ca (955 mg, 98% yield). HRMS(MALDI): C ３８ H ４０ N ６ O ８ Calculated value [M+Na] + : 731.2800, Measured value: 731.2791

[0283] Example 102 Synthesis of Compound 14Cb [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-3-(5-methyl-2-oxo-4-(1,2,4-triazole-1-yl)pyrimidine-1-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of compound 14Ca (915 mg, 1.29 mmol), 1,2,4-triazole (802 mg, 11.6 mmol), DIPEA (2.25 mL, 12.9 mmol), and acetonitrile (12.9 mL) was mixed with phosphorus oxychloride (204 μL, 2.19 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Ethyl acetate was added to the reaction mixture, and it was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure to obtain the crude compound 14Cb (1.08 g). HRMS(MALDI): C ４０ H ４１ N ９ O ７ Calculated value [M+Na] + : 782.3021, Measured value: 782.3019

[0284] Example 103 Synthesis of Compound 14Cc 4-amino-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Compound 14Cb (1.07 g, 1.29 mmol, crude) and acetonitrile (12.9 mL) were mixed with 28% aqueous ammonia (8.6 mL), and the mixture was stirred overnight at room temperature. Water was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and concentrated to obtain Compound 14Cc (748 mg, 87% yield in two steps). HRMS(MALDI): C ３６ H ３９ N ７ O ６ Calculated value [M+Na] +: 688.2854, Measured value: 688.2857

[0285] Example 104 Synthesis of Compound 14Cd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide Compound 14Cc (733 mg, 1.10 mmol) and pyridine (5.5 mL) were mixed with benzoic anhydride (374 mg, 1.65 mmol), and the mixture was stirred overnight at room temperature. 2 N aqueous sodium hydroxide solution (5.5 mL) was added to the reaction mixture, and the mixture was stirred at room temperature for 1 hour. Ethyl acetate was added to the reaction mixture, and it was washed with saturated aqueous sodium bicarbonate solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. Residual column chromatography (SiO ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 14Cd (744 mg, yield 88%). HRMS(MALDI): C ４３ H ４３ N ７ O ７ Calculated value [M+Na] + : 792.3116, Measured value: 792.3111

[0286] Example 105 Synthesis of Compound 14Ce N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 34 of the present invention) A mixture of Compound 14Cd (730 mg, 0.948 mmol), dichloromethane (9.5 mL), and DIPEA (0.495 mL, 2.84 mmol) was mixed with 2-cyanoethyl under ice cooling. N,N-diisopropyl chlorophosphoramide (0.423 mL, 1.90 mmol) was added, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture, and it was extracted with chloroform. The organic layer was passed through a phase separator, and the solvent was removed by distillation. The residue was analyzed by column chromatography (SiO₂). ２ The compound 14Ce (672 mg, 73% yield) was purified using hexane / ethyl acetate (50 / 50 to 0 / 100, NH:hexane / ethyl acetate (50 / 50 to 0 / 100) as compound 34 of the present invention. HRMS(MALDI): C ５２ H ６０ N ９ O ８ Calculated value at P [M+Na] + : 992.4195, Measured value: 992.4186 31 P-NMR (CDCl3) δ: 148.50, 148.58

[0287] Synthesis of ALNA[Trz]-G

[0288] Example 106 Synthesis of Compound 14Ga (1R,3R,4R,7S)-3-(2-amino-6-oxo-1H-purine-9-yl)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-5-carbothioamide 1 g (55.0 g, 58.9 mmol) of the compound synthesized by the method described in International Publication No. 2017 / 047816 was dissolved in THF (270 mL) and 1,1-thiocarbonyldiimidazole (21.0 g, 118 mmol) was added, and the mixture was stirred at room temperature for 2 hours. 28% aqueous ammonia (270 mL) was added to the reaction mixture, and the mixture was stirred at room temperature for 30 minutes, and then stirred at 50°C for 46 hours. Chloroform (700 mL) was added to the reaction mixture, and after stirring for a while, the organic layer was separated and dried over anhydrous sodium sulfate. After filtering off the insoluble material, the solvent was removed by distillation under reduced pressure, and the resulting residue was subjected to silica gel column chromatography (SiO₂). ２ The compound was crudely purified using chloroform / methanol (100 / 0 to 90 / 10). The resulting residue was dissolved in ethyl acetate (250 mL) and toluene (250 mL) was added. The solvent was removed by distillation under reduced pressure (solid precipitate), and diisopropyl ether (IPE) (50 mL) was added to the resulting suspension. The mixture was stirred at room temperature for 30 minutes. The precipitate was collected by filtration, the filter material was washed with IPE (50 mL), and then dried under reduced pressure to obtain compound 14Ga (27.9 g, yield 72%). MS (ESI): m / z = 656 [M + H] ＋

[0289] Example 107 Synthesis of Compound 14Gb Methyl (1R,3R,4R,7S)-3-(2-amino-6-oxo-1H-purine-9-yl)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-5-carboximidothioate 27.9 g, 42.5 mmol of Compound 14Ga was added dropwise to a solution of Compound 14Ga (27.9 g, 42.5 mmol) in THF (400 mL) under ice cooling with methyl iodide (4.24 mL, 68.1 mmol), and the mixture was stirred at room temperature for 24 hours. The reaction mixture was added with stirring to a mixture of sodium bicarbonate solution (prepared from saturated sodium bicarbonate solution (400 mL) and water (400 mL)) and chloroform (1400 mL). After stirring for a while, the organic layer was separated and dried over anhydrous sodium sulfate. The compound was filtered using Celite, and the filtrate was concentrated under reduced pressure and then azeotropically removed with toluene to obtain compound 14Gb (26.9g, yield 82%). MS (ESI): m / z = 670 [M + H] ＋

[0290] Example 108 Synthesis of Compound 14Gc [(1R,3R,4R,7S)-5-(N-acetyl-C-methylsulfanyl-carbonimidoyl)-3-(2-amino-6-oxo-1H-purine-9-yl)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 14Gb (26.9 g, 34.7 mmol) was dissolved in pyridine (100 mL), to which acetic anhydride (9.83 mL, 104 mmol) and DMAP (424 mg, 3.47 mmol) were added, and the mixture was stirred at room temperature for 4 hours. Ethyl acetate (400 mL) and saturated sodium bicarbonate solution (200 mL) were added to the reaction mixture, and after vigorous stirring for 20 minutes, the organic layer was separated. The organic layer was washed with water (2 × 200 mL) and saturated brine (200 mL), and then dried over anhydrous sodium sulfate. After filtering off insoluble matter, the solvent was removed by vacuum distillation, and the resulting residue was azeotropically removed with toluene to obtain compound 14 Gc (30.5 g). No purification was performed, and the compound was used directly in the next step. MS (ESI): m / z = 754 [M + H] ＋

[0291] Example 109 Synthesis of Compound 14Gd N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-formamidine To a solution of Compound 14Gc (30.5 g, 35.9 mmol) in 1,4-dioxane (300 mL), methylhydrazine (18.9 mL, 359 mmol) was added, and the mixture was stirred at room temperature for 2 hours, and then stirred at 50°C for 3 hours. Water (100 mL) was added to the reaction mixture and removed by distillation under reduced pressure. Chloroform (250 mL) was added, and after gentle stirring for a while, the organic layer was separated by passing it through a phase separator. After removing the solvent under reduced pressure, the mixture was azeotropically treated with toluene. The resulting residue was suspended in IPE (100 mL), placed in an ultrasonic bath for 20 minutes, and the precipitate was filtered off. After air drying, it was dried under reduced pressure. To a solution of the resulting residue in DMF (75 mL, 970 mmol), N,N-dimethylformamide dimethylacetal (50 mL, 375 mmol) was added, and the mixture was stirred at room temperature for 2 hours. The reaction solvent was removed under reduced pressure, and the resulting concentrated residue was subjected to silica gel column chromatography (SiO₂). ２ : Chloroform / methanol = 100 / 0 to 90 / 10, SiO ２ The compound was purified crudely using ethyl acetate / methanol (90 / 10 to 72 / 28). The crude product was washed with ethyl acetate (200 mL), filtered, and dried under reduced pressure to obtain compound 14 Gd (11.2 g, 40% yield). MS (ESI): m / z = 748 [M + H] ＋

[0292] Example 110 Synthesis of Compound 14Ge N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethyl-formamidine (Compound 35 of the present invention) To a solution of Compound 14Gd (6.00 g, 7.60 mmol) in dichloromethane (60 mL), DIPEA (5.30 mL, 30.6 mmol) was added under ice cooling, followed by 2-cyanoethyl N,N-diisopropyl chlorophosphoramide (5.12 mL, 23.0 mmol) was added dropwise, and the mixture was stirred at room temperature for 6 hours. The reaction mixture was cooled on ice, saturated sodium bicarbonate solution (120 mL) and chloroform (160 mL) were added, and the mixture was vigorously stirred for 15 minutes. The organic layer was then separated and dried over anhydrous sodium sulfate. After filtering off the insoluble material, the solvent was removed by distillation under reduced pressure, and the resulting residue was subjected to silica gel column chromatography (SiO₂). ２ The compound was purified using ethyl acetate / methanol (100 / 0 to 84 / 16) to obtain compound 14Ge (5.59 g, 74% yield) as compound 35 of the present invention. MS (ESI): m / z = 948 [M + H] ＋ 31 P-NMR (CDCl3) δ: 148.52, 148.59

[0293] Synthesis of ALNA[Trz]-A

[0294] Example 111 Synthesis of Compound 14Aa Benzotriazole-1-yl (benzotriazole-2-yl)methanymine To a solution of benzotriazole (7.70 g, 64.6 mmol) in EtOH (135 mL), a solution of cyanogen bromide (3.41 g, 32.2 mmol) in acetone (15 mL) was slowly added dropwise under ice cooling, followed by the slow addition of 2 N aqueous sodium hydroxide solution (16.2 mL, 32.4 mmol). After stirring under ice cooling for 30 minutes, the precipitate was collected by filtration, and the filtered material was washed with cold ethanol (80 mL). Compound 14Aa (5.14 g, yield 61%) was obtained by air drying followed by vacuum drying.1 H NMR (400 MHz, CHLOROFORM- d δ ppm 6.92 - 6.98 (m, 1 H) 7.46 - 7.55 (m, 2 H) 7.58 - 7.65 (m, 1 H) 7.77 (ddd, J=8.35, 7.06, 1.03 Hz, 1 H) 8.17 - 8.22 (m, 1 H) 8.22 - 8.27 (m, 1 H) 8.31 - 8.37 (m, 1 H) 9.67 (s, 1 H) MS (ESI): Not detected

[0295] Example 112 Synthesis of Compound 14Ae (1R,3R,4R,7S)-3-(6-aminopurine-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-ol Compound 1a (10.3 g, 17.9 mmol) was gradually added to a suspension of N-(9H-purine-6-yl)benzamide (5.15 g, 21.5 mmol) in toluene (200 mL), followed by the addition of BSA (38 mL, 120 mmol), and the mixture was vigorously stirred at 60°C for 30 minutes. At the same temperature, TMSOTf (0.324 mL, 1.79 mmol) was added, and the mixture was stirred at 60°C for 15 minutes. The reaction mixture was cooled with ice water, and then added to a mixture of ice-cooled IPE (100 mL), water (100 mL), and saturated sodium bicarbonate solution (100 mL) under vigorous stirring. After vigorous stirring for 20 minutes, insoluble matter was filtered off with Celite. The organic layer of the filtrate was separated, washed with saturated brine (200 mL), dried over anhydrous sodium sulfate, and the solvent was removed to obtain the residue of crude compound 14Gb. Compound 14Aa (4.72 g, 17.9 mmol) was added to the obtained residue in a solution of THF (200 mL), and the mixture was stirred at room temperature for 92 hours, and then stirred at 50°C for 9 hours. Ethyl acetate (400 mL) and saturated sodium bicarbonate solution (200 mL) were added to the reaction mixture, and after stirring for 20 minutes, the organic layer was separated. The organic layer was washed with water (300 mL) and saturated brine (100 mL), then dried over anhydrous sodium sulfate. After filtering off insoluble matter, the solvent was removed by distillation to obtain a residue of crude compound 14 Gc. To a pyridine (65 mL) solution of the obtained residue, anhydrous acetic acid (5.08 mL, 53.8 mmol) and DMAP (219 mg, 1.79 mmol) were added, and the mixture was stirred at room temperature for 3 hours. Ethyl acetate (400 mL) and saturated sodium bicarbonate solution (200 mL) were added to the reaction mixture, and after stirring for 20 minutes, the organic layer was separated. The organic layer was washed with water (300 mL) and saturated brine (100 mL), then dried over anhydrous sodium sulfate. After filtering off insoluble matter, the solvent was removed by reduced pressure distillation, and then azeotropic distillation with toluene was performed to obtain a residue of crude compound 14 Gd. To the obtained residue, a 1,4-dioxane (100 mL) solution was met with methylhydrazine (9.44 mL, 179 mmol) dropwise while cooling with cold water, and the mixture was stirred at room temperature for 3 hours.The mixture was heated to 50°C and stirred for 10 hours. After adding water (100 mL) to the reaction mixture, the solution was removed by vacuum distillation, and the residue was extracted by liquid-liquid extraction with chloroform (2 × 150 mL). The organic layer was washed with saturated brine (100 mL) and dried over anhydrous sodium sulfate. After filtering off insoluble matter, the solvent was removed by vacuum distillation, and the resulting residue was purified by silica gel column chromatography (NH silica: chloroform / methanol = 100 / 0 to 99 / 1) to obtain compound 14Ae (4.91 g, yield 41%). MS (ESI): m / z = 675 [M-H]. －

[0296] Example 113 Synthesis of Compound 14Af N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide A mixture of Compound 14Ae (4.80 g, 7.10 mmol) and pyridine (10 mL) was mixed with benzoyl chloride (2.48 mL, 21.3 mmol) under ice cooling, and the mixture was stirred under ice cooling for 3 hours. 2 N aqueous sodium hydroxide solution (25 mL, 50 mmol) was added to the reaction mixture, and the mixture was stirred at room temperature for 2 hours. The reaction mixture was extracted four times with chloroform (50 mL), the organic layer was passed through a phase separator, and then dried over anhydrous sodium sulfate. The solution was filtered by Celite and then concentrated. Residual column chromatography (SiO ２ The compound was purified by chloroform / methanol (100 / 0 to 93 / 7) to obtain compound 14Af (4.60 g, 83% yield). MS (ESI): m / z = 781 [M + H] ＋

[0297] Example 114 Synthesis of Compound 14Ag N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide (Compound 36 of the present invention) A mixture of Compound 14Af (4.26 g, 5.46 mmol) and dichloromethane (50 mL) was mixed with DIPEA (3.78 mL, 21.8 mmol) and 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (3.66 mL, 16.4 mmol) under ice cooling, and the mixture was stirred at room temperature for 2 hours. The reaction mixture was cooled on ice, 100 mL of saturated sodium bicarbonate aqueous solution was added, and the mixture was extracted with chloroform (100 mL). The organic layer was dried over anhydrous sodium sulfate, and insoluble matter was filtered off to remove the solvent. The residue was then subjected to column chromatography (SiO₂). ２ The compound was purified using ethyl acetate / methanol (100 / 0 to 94 / 6) and NH silica (ethyl acetate / methanol (100 / 0 to 93 / 7)) to obtain compound 14Ag (3.88g, yield 67%) as compound 36 of the present invention. MS (ESI): m / z = 980 [M + H] ＋ 31 P-NMR (CDCl3) δ: 148.84, 149.04

[0298] Synthesis of ALNA[Oxz]-T

[0299] Example 115 Synthesis of Compound 15Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 14Tc (2.10 g, 2.88 mmol) and EtOH (14.4 mL) was mixed with hydroxylamine (50% aqueous solution, 1.90 mL, 28.8 mmol), and the mixture was stirred at room temperature for 2 days. The reaction mixture was concentrated, and the residue was subjected to column chromatography (SiO₂). ２The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 15Ta (1.34 g, 71% yield). HRMS(MALDI): C ３５ H ３５ N ５ O ８ Calculated value [M+Na] + : 676.2378, Measured value: 676.2363

[0300] Example 116 Synthesis of Compound 15Tb 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 37 of the present invention) A mixture of Compound 15Ta (300 mg, 0.459 mmol), dichloromethane (4.6 mL), and DIPEA (240 μL, 1.38 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (205 μL, 0.918 mmol), and the mixture was stirred at room temperature under a nitrogen atmosphere for 5 days. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using the following methods: hexane / ethyl acetate = 60 / 40 to 10 / 90, Diol: hexane / ethyl acetate = 70 / 30 to 20 / 80, NH: chloroform / methanol = 100 / 0 to 95 / 5) to obtain compound 15Tb (214 mg, yield 55%) as compound 37 of the present invention. HRMS(MALDI): C ４４ H ５２ N ７ O ９ Calculated value at P [M+Na] + : 876.3456, Measured value: 876.3441 31 P-NMR (CDCl3) δ: 148.83, 149.09

[0301] Synthesis of ALNA[Oxz]-mC

[0302] Example 117 Synthesis of Compound 15Ca [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 15Ta (999 mg, 1.53 mmol), DMAP (18.7 mg, 0.153 mmol), and pyridine (7.7 mL) was mixed with acetic anhydride (217 μL, 2.30 mmol), and the mixture was stirred at room temperature for 2 days. Ethyl acetate was added to the reaction mixture and washed with saturated sodium bicarbonate aqueous solution, water, and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure to obtain compound 15Ca (1.10 g, quantitative analysis proceeding). HRMS(MALDI): C ３７ H ３７ N ５ O ９ Calculated value [M+Na] + : 718.2483, Measured value: 718.2470

[0303] Example 118 Synthesis of Compound 15Cb [(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-5-(5-methyl-1,2,4-oxadiazole-3-yl)-3-[5-methyl-2-oxo-4-(1,2,4-triazole-1-yl)pyrimidine-1-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 15Ca (1.05 g, 1.51 mmol), 1,2,4-triazole (939 mg, 13.6 mmol), DIPEA (2.63 mL, 15.1 mmol), and acetonitrile (15 mL) were mixed with phosphorus oxychloride (239 μL, 2.57 mmol) under ice cooling, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Ethyl acetate was added to the reaction mixture, and it was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, and after filtering off insoluble matter, the mixture was concentrated under reduced pressure to obtain compound 15Cb (1.32 g) as the crude product. HRMS(MALDI): C ３９ H ３８N ８ O ８ Calculated value [M+Na] + : 769.2705, Measured value: 769.2707

[0304] Example 119 Synthesis of Compound 15Cc 4-amino-1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Compound 15Cb (1.30 g, 1.51 mmol, crude) and acetonitrile (15.1 mL) were mixed with 28% aqueous ammonia (10.1 mL), and the mixture was stirred overnight at room temperature. Water was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and concentrated to obtain Compound 15Cc (0.96 g, 97% yield in 2 steps). HRMS(MALDI): C ３５ H ３６ N ６ O ７ Calculated value [M+Na] + : 675.2538, Measured value: 675.2539

[0305] Example 120 Synthesis of Compound 15Cd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-hydroxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide A mixture of Compound 15Cc (0.93 g, 1.42 mmol) and pyridine (7.1 mL) was mixed with benzoic anhydride (482 mg, 2.13 mmol), and the mixture was stirred overnight at room temperature. 2 N aqueous sodium hydroxide solution (7.1 mL) was added to the reaction mixture and stirred at room temperature for 1 hour. Ethyl acetate was added to the reaction mixture and washed with saturated aqueous sodium bicarbonate solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. Residual column chromatography (SiO ２The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 15Cd (958 mg, yield 89%). HRMS(MALDI): C ４２ H ４０ N ６ O ８ Calculated value [M+Na] + : 779.2800, Measured value: 779.2794

[0306] Example 121 Synthesis of Compound 15Ce N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(5-methyl-1,2,4-oxadiazole-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 38 of the present invention) A mixture of Compound 15Cd (949 mg, 1.25 mmol), dichloromethane (12.5 mL), and DIPEA (0.653 mL, 3.75 mmol) was mixed with 2-cyanoethyl under ice cooling. N,N-diisopropyl chlorophosphoramide (0.559 mL, 2.50 mmol) was added, and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture, and it was extracted with chloroform. The organic layer was passed through a phase separator, and the solvent was removed by distillation. The residue was analyzed by column chromatography (SiO₂). ２ The compound was purified using hexane / ethyl acetate (80 / 20 to 30 / 70, NH:hexane / ethyl acetate (50 / 50 to 0 / 100)) to obtain compound 15Ce (834 mg, 70% yield) as compound 38 of the present invention. HRMS(MALDI): C ５１ H ５７ N ８ O ９ Calculated value at P [M+Na] + : 979.3878, Measured value: 979.3876 31 P-NMR (CDCl3) δ: 148.98, 149.27

[0307] Synthesis of ALNA[Tdz]-T

[0308] Example 122 Synthesis of Compound 16Ta 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione A mixture of Compound 1a (3.00 g, 5.25 mmol), 5-chloro-3-methyl-1,2,4-thiadiazole (848 mg, 6.30 mmol), DIPEA (2.72 mL, 15.7 mmol), and DMSO (26 mL) was stirred at 120°C for 2 hours. Ethyl acetate was added to the reaction mixture and washed with water and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. The residue was analyzed by column chromatography (SiO2). ２ The compound was purified using chloroform / methanol (100 / 0 to 95 / 5) to obtain compound 16TaAB37420-001 (3.30 g, 94% yield). MS (ESI): m / z = 670 [M + H] ＋

[0309] Example 123 Synthesis of Compound 16Tb 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile (Compound 39 of the present invention) A mixture of Compound 16Ta (2.26 g, 3.37 mmol), dichloromethane (17 mL), and DIPEA (1.75 mL, 10.1 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (1.51 mL, 6.77 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２The compound was purified using a diol (hexane / ethyl acetate = 70 / 30 to 20 / 80, Diol:hexane / ethyl acetate = 70 / 30 to 20 / 80) to obtain compound 16Tb (2.45 g, yield 84%) as compound 39 of the present invention. MS (ESI): m / z = 870 [M + H] ＋ 31 P-NMR (CDCl3) δ: 149.23, 149.51

[0310] Synthesis of ALNA[Tdz]-mC

[0311] Example 124 Synthesis of Compound 16mCa [[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxopyrimidine-1-yl)-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate A mixture of Compound 16Ta (5.92 g, 8.84 mmol), DMAP (120 mg, 0.982 mmol), and pyridine (18 mL) was mixed with acetic anhydride (1.25 mL, 13.2 mmol), and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated, ethyl acetate was added to the residue, and it was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the compound was concentrated under reduced pressure to obtain 16 mCa (5.69 g, 90% yield). MS (ESI): m / z = 712 [M + H] ＋

[0312] Example 125 Synthesis of Compound 16mCb [[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-[5-methyl-2-oxo-4-(1,2,4-thiadiazole-1-yl)pyrimidine-1-yl]-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]acetate Compound 16mCa (5.52 g, 7.75 mmol), 1,2,4-triazole (4.82 g, 69.8 mmol), DIPEA (13.4 mL, 77.5 mmol), and acetonitrile (39 mL) were mixed with phosphorus oxychloride (1.23 mL, 13.2 mmol) under ice cooling, and the mixture was stirred at room temperature under a nitrogen atmosphere for 2 hours. Ethyl acetate was added to the reaction mixture, and it was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, and after filtering off insoluble matter, the mixture was concentrated under reduced pressure to obtain compound 16 mCb (6.18 g, including impurities) as the crude product.

[0313] Example 126 Synthesis of Compound 16mCc 4-amino-1-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one A mixture of Compound 16mCb (6.18 g, 7.75 mmol, including impurities) and acetonitrile (39 mL) was mixed with 28% aqueous ammonia (39 mL), and the mixture was stirred at room temperature for 4 days. Water was added to the reaction mixture and extracted with chloroform. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and the mixture was concentrated under reduced pressure. The residue was analyzed by column chromatography (SiO2). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain 16 mCc of the compound (4.50 g, 87% yield in two steps). MS (ESI): m / z = 667 [M-H] －

[0314] Example 127 Synthesis of Compound 16mCd N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide A mixture of Compound 16mCc (4.37 g, 6.53 mmol), benzoic anhydride (2.22 g, 9.81 mmol), and pyridine (13 mL) was stirred overnight at room temperature. 2 N aqueous sodium hydroxide solution (13 mL, 26 mmol) was added to the reaction mixture, and the mixture was stirred at room temperature for 1.5 hours. Ethyl acetate was added to the reaction mixture, and it was washed with saturated aqueous sodium bicarbonate solution and saturated brine. The organic layer was dried over anhydrous magnesium sulfate, insoluble matter was filtered off, and then concentrated under reduced pressure. The residue was subjected to column chromatography (SiO₂). ２ The compound was purified using chloroform / methanol (100 / 0 to 90 / 10) to obtain compound 16mCdAB37471-001 (4.76 g, 94% yield). MS (ESI): m / z = 773 [M + H] ＋

[0315] Example 128 Synthesis of Compound 16mCe N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(3-methyl-1,2,4-thiadiazole-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]benzamide (Compound 40 of the present invention) A mixture of Compound 16mCd (4.62 g, 5.98 mmol), dichloromethane (12 mL), and DIPEA (3.10 mL, 17.9 mmol) was mixed with 2-cyanoethyl N,N-diisopropylchlorophosphoroamide (2.67 mL, 12.0 mmol), and the mixture was stirred overnight at room temperature under a nitrogen atmosphere. A saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and the solvent was removed by distillation. The residue was subjected to column chromatography (SiO₂). ２The compound was purified using hexane / ethyl acetate (80 / 20-30 / 70, NH:hexane / ethyl acetate (70 / 30-20 / 80)) to obtain compound 16mCe (3.57g, yield 61%) as compound 40 of the present invention. MS (ESI): m / z = 974 [M + H] ＋ 31 P-NMR (CDCl3) δ: 149.45, 149.78

[0316] ALNA[Ms]-mC can also be synthesized by converting the nucleic acid base portion of ALNA[Ms]-T nucleoside as follows: Synthesis of compound 2Cf

[0317] Example 129 Synthesis of Compound 2Cd 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-methylsulfonyl-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-6-(1,2,4-triazole-1-yl)-1,6-dihydropyrimidine-2-one 2Tb (14.1 g, 0.019 mol) was dissolved in acetonitrile (310 mL), triethylamine (97.29 mL, 0.961 mol) was added, and the mixture was stirred at 0°C for 15 minutes. 1,2,4-triazole (30.36 g, 0.439 mol) was added to the reaction solution and stirred at 0°C for 15 minutes. Then phosphorus oxychloride (4.44 mL, 0.028 mol) was added and stirred at 0°C for 15 minutes, and the temperature was raised to room temperature and stirred for 2 hours. The reaction mixture was concentrated under reduced pressure, and then ethyl acetate (200 mL) and water (100 mL) were added and separated. The organic layer was washed twice with sodium carbonate (100 mL), dried over sodium sulfate, and concentrated under reduced pressure to obtain crude product 2Cd (11.8 g).

[0318] Example 130 Synthesis of Compound 2Ce 6-amino-3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Crude product 2Cd (11.8 g) was dissolved in 1,4-dioxane (118 mL), and 25% aqueous ammonia (118 mL) was added and the mixture was stirred overnight at room temperature. The reaction solution was concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (dichloromethane / methanol, 95 / 5 to 94 / 6). This was stirred in a mixture of dichloromethane / hexane (10 / 90), and the precipitate was filtered off to obtain compound 2Ce (8.3 g, 2-step yield 64%). MS (ESI): m / z = 649.3 (M+H) +

[0319] Example 131 Synthesis of Compound 2Cf N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxopyrimidine-4-yl]dihydropyrimidine-2-one Compound 2Ce (8.3 g, 0.012 mol) was added to a solution of compound 2Ce (63 mL) in DMF (2.57 g, 0.011 mol) and stirred at room temperature for 24 hours. The reaction mixture was diluted with ethyl acetate (200 mL) and washed twice with water (100 mL). The organic layer was sequentially washed with sodium carbonate solution (100 mL) and saturated brine (100 mL) and dried over sodium sulfate. This was concentrated under reduced pressure, and the resulting residue was purified by silica gel column chromatography (dichloromethane / methanol, 99.5 / 0.5–99 / 1). This was stirred in a mixture of dichloromethane / hexane (10 / 90), and the precipitate was filtered to obtain compound 2Cf (4.0 g, 47% yield). MS (ESI): m / z = 753.1 (M + H) +

[0320] Furthermore, ALNA[Ms]-mC nucleoside can also be synthesized as follows: Synthesis of compound 2Cj

[0321] Example 132 Synthesis of Compound 2Cg 1-[(1R,3R,4R,7S)-7-benzyloxy-1-(benzyloxymethyl)-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione 1-[(1R,3R,4R,7S)-7-benzyloxy-1-(benzyloxymethyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2,4-dione (1h) (20.00g, ) synthesized by the method described in International Publication No. 2017 / 047816 To a mixed solution of 21.61 mmol of dichloromethane (200 mL), triethylamine (15.5 mL, 111 mmol) was added, and mesylchloride (4.15 mL, 53.4 mmol) was added under ice bath conditions. The mixture was stirred under ice bath conditions for 4.5 hours. 5% sodium bicarbonate solution (60 mL) was added to the reaction mixture and stirred, then the mixture was separated. The aqueous layer was extracted with dichloromethane (40 mL), and the organic layer of dichloromethane was combined and mixed. The organic layer was washed with 15% saline solution (60 mL), and the solvent was removed by distillation. Methanol (90 mL) was added to the concentrated residue and suspended washing was performed. The resulting precipitate was filtered and vacuum dried to obtain 2 C g of compound (21.94 g, yield 94%). MS (ESI): m / z = 528 (M+H) +

[0322] Example 133 Synthesis of Compound 2Ch 1-[(1R,3R,4R,7S)-7-benzyloxy-1-(benzyloxymethyl)-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-4-(1,2,4-triazole-1-yl)pyrimidine-2-one Compound 2Ch (3.4 g) was obtained as a crude product from 2C g (3.0 g, 5.6 mmol) in the same manner as in Example 129.

[0323] Example 134 Synthesis of Compound 2Ci 4-amino-1-[(1R,3R,4R,7S)-7-benzyloxy-1-(benzyloxymethyl)-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Compound 2Ci (2.6 g, 87% yield) was obtained from Compound 2Ch (3.4 g, 5.8 mmol) in the same manner as in Example 130. MS (ESI): m / z = 527.2 (M + H) +

[0324] Example 135 Synthesis of Compound 2Cj 4-amino-1-[(1R,3R,4R,7S)-7-hydroxy-1-(hydroxymethyl)-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methylpyrimidine-2-one Compound 2Ci (2.6 g, 4.9 mmol) was dissolved in acetic acid (28.6 mL), 20% palladium hydroxide / carbon (0.35 g) was added, and the mixture was stirred at room temperature under a hydrogen atmosphere for 16 hours. After filtering off the insoluble matter, the mixture was concentrated under reduced pressure. 1-butanol and IPE were added to the residue and stirred, and the precipitate was filtered off. The obtained solid was recrystallized in methanol to obtain Compound 2Cj (1.0 g, 58% yield). MS (ESI): m / z = 346.9 (M + H) +

[0325] ALNA[Ms]-G can be used to synthesize monomers in which the guanine moiety is protected with a dimethylaminomethylenyl group, as described below. Furthermore, when monomers with this protection method are used in oligomer synthesis, it is possible to control the generation of by-products that may occur when using 2Gd, in which the 6th position of guanine is DPC protected, in oligomer synthesis.

[0326] Example 136 Synthesis of Compound 2Ge 2-amino-9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-1H-purine-6-one Compound 2Gc (1000 mg, 1.1 mmol) was dissolved in tetrahydrofuran (10 mL) at room temperature, and 28% aqueous ammonia (5 mL) was added and the mixture was stirred overnight at room temperature. Further, 28% aqueous ammonia (15 mL) was added and the mixture was stirred at 70°C for 8 hours. Water and dichloromethane were added at room temperature, and after stirring, the organic layer was collected and dried over sodium sulfate. The residue was filtered, and after solvent removal, compound 2Ge (620 mg, yield 86%) was obtained by silica gel column chromatography (chloroform / methanol, 97 / 3 to 92 / 8). MS (ESI): m / z = 675 (M+H) +

[0327] Example 137 Synthesis of Compound 2Gf N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethylformamidine Compound 2Ge (150 mg, 0.22 mmol) was dissolved in tetrahydrofuran (2.22 mL), and N,N-dimethylformamide dimethylacetal (132 mg, 1.11 mmol) was added at room temperature and stirred for a time. The mixture was added at room temperature and extracted once with ethyl acetate (2 mL). The resulting organic layer was washed with brine and dried over sodium sulfate. The residue was filtered, the solvent was removed, and then the compound was purified by silica gel column chromatography (chloroform / methanol = 99 / 1, chloroform / methanol = 93 / 7) to obtain 2Gf (145 mg, yield 89%). MS (ESI): m / z = 728 (MH)-

[0328] Example 138 Synthesis of Compound 2 Gg N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-N,N-dimethylformamidine Compound 2 Gf (900 mg, 1.2 mmol) was dissolved in dichloromethane (15 mL), and N,N-diisopropylethylamine (747 mg, 5.8 mmol) and 2-cyanoethyl-N,N-diisopropylchlorophosphoramidide (1061 mg, 4.5 mmol) were added at room temperature and the mixture was stirred overnight. Saturated baking soda water and dichloromethane were added at room temperature, and the organic layer was separated. The resulting organic layer was dried over sodium sulfate, and the residue was filtered. After solvent removal, the compound was purified by amino silica gel column chromatography (chloroform / methanol, 100 / 0–97 / 3) and diol silica gel column chromatography (chloroform / methanol, 100 / 0–97 / 3) to obtain 2 Gg (690 mg, 60% yield) of the compound. MS (ESI): m / z = 930 (M+H) +

[0329] ALNA[Ms]-G can be used to synthesize monomers in which the guanine moiety is protected solely by isobutyroyl groups, as described below. Furthermore, when monomers with this protection method are used in oligomer synthesis, it is possible to control the generation of by-products that may occur when using 2Gd, in which the 6th position of guanine is DPC protected, for oligomer synthesis.

[0330] Example 139 Synthesis of Compound 2Gh N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Compound 2Ge (100 mg, 0.15 mmol) was dissolved in pyridine (1.4 mL), and at room temperature, N,N-dimethyl-4-aminopyridine (29 mg, 0.24 mmol) and 2-methylpropanoyl 2-methylpropanoate (100 μL, 0.6 mmol) were added and the mixture was stirred at 100°C for 4 hours. Further, 2-methylpropanoyl 2-methylpropanoate (100 μL, 0.6 mmol) was added and the mixture was stirred at 100°C for 2 hours. At room temperature, saturated baking soda water and sodium acetate were added, and the organic layer was separated. The obtained organic layer was dried over sodium sulfate. The residue was filtered, and after solvent removal, it was purified by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 20 / 80). Furthermore, the compound was dissolved in tetrahydrofuran (1 mL), 0.1 N sodium hydroxide aqueous solution (1 mL) was added, and the mixture was stirred at 0°C for 40 minutes. Water and ethyl acetate were added to the reaction mixture, and the organic layer was separated. After washing with saturated ammonium chloride aqueous solution, the organic layer was separated again. After drying over sodium sulfate, the residue was filtered, and solvent removal was performed to obtain 2 Gh of the compound (56 mg, 50% yield). MS (ESI): m / z = 745 (M+H) +

[0331] Example 140 Synthesis of Compound 2Gi N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Molecular sieve 3A was added to dichloromethane (3.6 mL) and stirred for 1 hour. Compound 2Gh (500 mg, 0.67 mmol), 1-methylimidazole (10.9 mg, 0.1 mol), tetrazole (84 mg, 1.2 mmol), and 3-bis(diisopropylamino)phosphanyloxypropanenitrile (949 mg, 3.1 mmol) were added at room temperature and stirred for 6 hours. Saturated baking soda water was added at room temperature, and the mixture was extracted twice with dichloromethane. The resulting organic layer was dried over sodium sulfate, and the residue was filtered. After solvent removal, compound 2Gi (500 mg, 79% yield) was obtained by silica gel column chromatography (hexane / ethyl acetate, 50 / 50 to 25 / 75). MS (ESI): m / z = 946 (M+H) +

[0332] Furthermore, the ALNA[Ms]-G monomer, in which the guanine moiety is protected only by an isobutyroyl group, can also be synthesized directly from compound 1a by transglycosylation as follows.

[0333] Example 141 Synthesis of Compound 2Gj N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Compound 1a (5.0 g, 8.75 mmol) and 2-methyl-N-(6-oxo-1,9-dihydropurine-2-yl)propanamide (3.87 g, 17.5 mmol) were mixed in 1,2-dichloroethane (30 mL) and BSA (21.4 mL, 87.5 mmol) was added and the mixture was stirred at 60°C for 30 minutes. Subsequently, TMSOTf (0.254 mL, 1.31 mmol) was added and the mixture was stirred for 1.5 hours. After cooling, chloroform (50 mL) and saturated sodium bicarbonate aqueous solution (50 mL) were added to the reaction mixture and stirred. After suction filtration of insoluble matter, the organic layer was washed with water and saturated brine, dried over magnesium sulfate, and concentrated. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 90 / 10) to obtain compound 2 Gj (3.83 g, yield 59%). MS (ESI): m / z = 739.5 (M + H) +

[0334] Example 142 Synthesis of Compound 2Gk N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-methylsulfonyl-7-trimethylsilyloxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Compound 2Gj (1.0 g, 1.35 mmol) and pyridine (0.327 mL, 4.06 mmol) were dissolved in dichloromethane (7 mL), to which methanesulfonic anhydride (284 mg, 1.63 mmol) was added under ice cooling and stirred for 45 minutes under ice cooling. Saturated sodium bicarbonate aqueous solution was added to the reaction mixture and extracted with chloroform. The organic layer was passed through a phase separator and then concentrated. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 90 / 10) to obtain compound 2 Gk (657 mg, 59% yield). MS (ESI): m / z = 817.4 (M + H) +

[0335] Example 143 Synthesis of Compound 2Gh N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Compound 2Gk (3.16 g, 3.87 mmol) was added to a solution of compound 2Gk (8 mL) in THF (4.6 mL, 4.6 mmol) and stirred at room temperature for 1 hour. The reaction mixture was concentrated, ethyl acetate was added, and the organic layer was washed with water and saturated brine. The organic layer was dried over magnesium sulfate and concentrated. The resulting residue was purified by silica gel column chromatography (chloroform / methanol, 100 / 0 to 90 / 10) to obtain 2 GHz of the compound (2.57 g, 89% yield). MS (ESI): m / z = 745.5 (M + H) +

[0336] Furthermore, compound 2Gh can also be synthesized from compound 2Gb as follows.

[0337] Example 144 Synthesis of Compound 2Gh N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purine-2-yl]-2-methyl-propanamide Compound 2Gb (1010 mg, 1.0 mmol) was dissolved in tetrahydrofuran (10 mL), and tetrabutylammonium fluoride (1 mol / L tetrahydrofuran solution, 3 mL, 3.0 mmol) was added at room temperature and the mixture was stirred at 70°C for 24 hours. Furthermore, tetrabutylammonium fluoride (1 mol / L tetrahydrofuran solution, 9 mL, 9.0 mmol) was added at room temperature and the mixture was stirred at 80°C for 8 hours. After solvent removal, the compound was purified by silica gel column chromatography (chloroform / methanol, 98 / 2–93 / 7). Further silica gel column chromatography (chloroform / methanol, 100 / 0–94 / 6) yielded 2 Gh of the compound (570 mg, 77% yield). MS(ESI): m / z = 745 (M+H) +

[0338] Example 145 Synthesis and Purification of Oligonucleotide Analogues (in vitro) Using the various amidites (compounds 1 to 44 of the present invention) obtained in the above examples, the oligonucleotide analogue compounds listed in Tables 1 to 4 below were synthesized on a 0.2 or 1.0 μmol scale using a DNA / RNA oligonucleotide automated synthesizer ns-8II (manufactured by Gene Design Co., Ltd.) with CPG or polystyrene support. All amidites were prepared in a 0.1 M acetonitrile solution, and the coupling time for the non-natural nucleoside was 10 minutes. The other steps were carried out under the standard conditions of the ns-8II. Activator 42 (Sigma-Aldrich) was used as the activator, and Sulfurizing Reagent II (Green Research Corporation) was used for thiolation. The synthesized oligonucleotides were reacted with 28% aqueous ammonia at 60-65°C for 8 hours to cleave from the support and deprotect the base portion. After concentrating and removing ammonia, the solution was purified by reverse-phase HPLC.

[0339] Example 146 Synthesis and Purification of Oligonucleotide Analogues (in vivo) Using the various amidites (compounds 1 to 44 of the present invention) obtained in the above examples, the oligonucleotide analogue compounds listed in Table 5 below were synthesized on a 20 μmol scale using a polystyrene support with an AKTA oligopilot plus 10 automated DNA / RNA oligonucleotide synthesizer (manufactured by GE Healthcare Japan Co., Ltd.). DNA amidites were prepared in a 0.1 M acetonitrile solution, and unnatural amidites in a 0.05 M acetonitrile solution. The coupling and recycling time for unnatural nucleosides was 20 minutes, and when introducing the first base to the universal support, the coupling, thiolation, and capping steps were each performed twice consecutively. All other steps were performed under the standard conditions of the AKTA oligopilot plus 10. Activator 42 (Sigma-Aldrich) was used as the activator, and Sulfurizing Reagent II (Green Research Corporation) was used for thiolation. The synthesized oligonucleotides were reacted with 28% aqueous ammonia at 60-65°C for 8 hours to cleave them from the support and deprotect the base portion. After concentrating and removing the ammonia, the solution was purified using an anion exchange column. Excess salts remaining after anion exchange were removed using a desalting column.

[0340] The synthesized oligonucleotide analogs were purified and their purity confirmed by reverse-phase HPLC under the following conditions. Reverse-phase HPLC Mobile phase: Solution A: 20 mM hexylamine acetate aqueous solution Solution B: Acetonitrile Gradient: A:B = 90:10 → 50:50 (40 min) or A:B = 90:10 → 40:60 (45 min) Column used: Analytical Waters XBridge@ Oligoncleotide BEH C18 Column, 130 Å, 2.5 μm, 4.6 mm * 50 mm Preparative Waters XBridge@ Oligoncleotide BEH C18 OBD™ Prep Column, 130 Å, 2.5 μm, 10 mm * 50 mm

[0341] Flow rate: Analysis 1 ml / min, Preparative 4 ml / min; Column temperature: 60°C; Detection: UV (260 nm)

[0342] Anion exchange purification Mobile phase: Solution A: 20mM Tris-HCl (pH 8.0) aqueous solution Solution B: 20mM Tris-HCl (pH 8.0), 1M NaBr aqueous solution Column used: GE HiTrap CaptQ ImpRes (Anion exchange) 5ml Flow rate: 5ml / min Column temperature: Room temperature Detection: UV (260nm)

[0343] Desalting column Mobile phase: Solution A: H ２ OB liquid: H ２ Column used: GE HiPrep 26 / 10 Desalting; Flow rate: 10 ml / min; Column temperature: Room temperature

[0344] The molecular weight of the synthesized oligonucleotide analogs was determined using Waters ZQ under the following conditions: Mobile phase: Solution A: 400 mM hexafluoroisopropanol, 15 mM triethylamine aqueous solution Solution B: methanol Gradient: A:B = 80:20 → 70:30 (2.5 min) or A:B = 90:10 → 40:60 (45 min) Column used: Analytical Waters ACQUITY UPLC @ Oligonucleotide BEH C18 Column, 130 Åm 1.7 μm, 2.1 mm * 100 mm Flow rate: 0.2 ml / min Column temperature: 60°C Detection: UV (260 nm)

[0345] Table 1. Mass spectral measurement results for each Tm sequence gcgttT(X)tttgct (Sequence ID 1) (Here, lowercase letters represent each nucleic acid base of DNA, T(X) represents each artificial nucleic acid species containing thymine, and all phosphate bonds are phosphodiesters)

[0346] Table 2 Mass spectral measurement results for each SRB1 (2-10-2) sequence T(X)C(X)agtcatgactT(X)C(X) (Sequence ID 2) (Here, lowercase letters represent each nucleic acid base of DNA, T(X) and C(X) represent each artificial nucleic acid species containing thymine and each artificial nucleic acid species containing 5-methylcytosine, respectively, and all phosphate bonds are phosphorothioates)

[0347] Table 3 Mass spectral measurement results for each SRB1 (3-10-3) sequence T(X)T(X)C(X)agtcatgactT(X)C(X)C(X) (Sequence ID 3) (Here, lowercase letters represent each nucleic acid base of DNA, T(X) and C(X) represent each artificial nucleic acid species containing thymine and the artificial nucleic acid species containing 5-methylcytosine, respectively, and all phosphate bonds are phosphorothioates)

[0348] Table 4 Mass spectral measurement results for each antimiR-21 sequence A(m)C(X)atC(X)agtC(X)tgaT(X)aagC(X)tA(m) (Sequence ID 4) (Here, A(m) represents 2'-MOE adenosine, lowercase letters represent each nucleic acid base of DNA, T(X) and C(X) represent each artificial nucleic acid species containing thymine and the artificial nucleic acid species containing 5-methylcytosine, respectively, and all phosphate bonds are phosphorothioates)

[0349] Table 5 Mass spectral measurement results for each Malat1 sequence G(X)T(X)T(X)cactgaatG(X)C(X)G(X) (Sequence ID 5) (Here, lowercase letters represent each nucleic acid base of DNA, T(X), C(X), and G(X) represent the artificial nucleic acid species containing thymine, the artificial nucleic acid species containing 5-methylcytosine, and the artificial nucleic acid species containing guanine, respectively, and all phosphate bonds are phosphorothioates)

[0350] Example 147 Evaluation of binding ability to target chain and mismatch selectivity The double-strand formation ability of oligonucleotides was investigated by annealing each of the following: an antisense strand containing various artificial nucleic acid species (where the sequence is gcgttT(X)tttgct (SEQ ID NO: 1), lowercase letters represent each nucleic acid base of DNA, and T(X) represents each artificial nucleic acid species containing thymine); a sense strand, i.e., a DNA strand having a sequence complementary to the antisense strand (where the sequence is agcaaaaaacgc (SEQ ID NO: 6), lowercase letters represent each nucleic acid base of DNA); an RNA strand having a complementary sequence (where the sequence is AGCAAAAAACGC (SEQ ID NO: 7), uppercase letters represent each nucleic acid base of RNA); and an RNA strand having three types of complementary sequences including a single base mismatch (where the sequence is AGCAAANAACGC (SEQ ID NO: 8), uppercase letters represent each nucleic acid base of RNA, and N represents uracil (U), guanine (G), and cytosine (C), respectively) to form a double helix, and then measuring the Tm value, which is the temperature at which 50% of the double helix dissociates. Specifically, a sample solution (150 μL) containing 100 mmol / L sodium chloride aqueous solution, 10 mmol / L sodium phosphate buffer (pH 7.4), 4 μmol / L antisense chain, and 4 μmol / L sense chain was heated to 95°C and then cooled to room temperature over 4 hours. A nitrogen stream was passed through the cell chamber of a spectrophotometer (JASCO, V-730, PAC-743R) to prevent condensation, and the sample solution was gradually cooled to 10°C. After maintaining this temperature for 1 minute, measurements were started. The temperature was increased to 80°C at a rate of 0.5°C per minute, and the absorbance at 260 nm was measured every 0.5°C. A cell with a lid was used to prevent concentration changes due to temperature rise. The results are shown in Table 6.

[0351] Table 6. Measurement results of each Tm value

[0352] As is clear from Table 6, antisense strands containing various artificial nucleic acids had sense strand binding ability and mismatch selection ability equivalent to or better than those containing natural DNA or the known ALNA ALNA[Me].

[0353] Example 147 In vitro SR-B1 knockdown activity test Hepa 1c1c7 cells 2.5 × 10⁶ cells per well 3 After seeding and culturing for 24 hours, various modified antisense oligonucleotides having sequences complementary to SRB1 were added at final concentrations of 100, 20, and 4 nmol / L, and quantitative PCR was performed after 48 hours. The same procedure was performed in 3 wells. Antisense activity was expressed as a percentage of inhibition of SRB1 expression when the antisense compound was added, based on the ratio of SRB1 to GAPDH in the negative control. The results are shown in Table 7.

[0354] Table 7 In vitro SRB1 knockdown activity The target gene (SRB1) knockdown activity of antisense oligonucleotides containing each artificial nucleic acid in two sequence patterns, 3-10-3 and 2-10-2, was demonstrated at Gymnosis 100 nM. The two sequence patterns are as follows: 3-10-3: T(X)T(X)C(X)agtcatgactT(X)C(X)C(X) (same as SEQ ID NO: 3 in Table 3 above) 2-10-2: T(X)C(X)agtcatgactT(X)C(X) (same as SEQ ID NO: 2 in Table 2 above) Lowercase letters represent each nucleic acid base of DNA, T(X) and C(X) represent each artificial nucleic acid species containing thymine and the artificial nucleic acid species containing 5-methylcytosine, respectively, and all phosphate bonds are phosphorothioates.

[0355] As is clear from Table 7, ALNA[Ms], ALNA[ipU], ALNA[2Pym], ALNA[Prz], ALNA[Trz], and ALNA[Oxz] exhibited potent in vitro target gene knockdown activity compared to the known ALNA, ALNA[Me].

[0356] Example 148: In vitro miRNA-21 inhibitory activity test 3.0 × 10 6HEK293 cells at a concentration of cells / ml were seeded in a 10 cm dish and cultured overnight in a CO2 incubator. The following day, 10 μg of a reporter plasmid containing the complementary sequence of miR-21 cloned into the multi-cloning site of the psiCHECK-2 vector (Promega) was transfected into the cells using FuGENE HD Transfection Reagent, and the cells were cultured in a CO2 incubator for approximately 24 hours. These cells were harvested and placed in a 96-well plate in a 2.0 × 10⁶ layer. 4 Cells were reseeded in cells / wells, and miR-21 inhibitors containing each artificial nucleic acid were added. After culturing the cells in a CO2 incubator for 96 hours, the luminescence values ​​of firefly luciferase and Renilla luciferase in the cells were detected using a plate reader with a Dual-Glo Luciferase Assay System. To correct for the effects of transfection efficiency and cell number, the ratio of the luminescence value due to firefly luciferase activity to the luminescence value due to Renilla luciferase activity was calculated. Furthermore, from the calculated ratio, the inhibition rate was calculated for cells containing the psiCHECK-2 vector (100% inhibition rate) and for cells containing the psiCHECK-2 vector with the cloned miR-21 complementary sequence (0% inhibition rate), and the inhibitory activity was determined. The results are shown in Table 8.

[0357] Table 8 In vitro miRNA-21 inhibitory activity The sequence of the antisense oligo used is as follows: A(m)C(X)atC(X)agtC(X)tgaT(X)aagC(X)tA(m) (same as sequence number 4 in Table 4 above). Here, A(m) represents 2'-MOE adenosine, the lowercase letters represent each nucleic acid base of DNA, and T(X) and C(X) represent each artificial nucleic acid species containing thymine and the artificial nucleic acid species containing 5-methylcytosine, respectively. All phosphate bonds are phosphorothioates.

[0358] As is clear from Table 8, ALNA[mU], ALNA[ipU], ALNA[dmU], ALNA[Trz], and ALNA[Oxz] exhibited potent in vitro microRNA inhibitory activity compared to the known ALNA, ALNA[Me].

[0359] Example 149 In vivo MALAT1 knockdown activity test Six-week-old C57BL / 6J mice (male, Charles River, Japan) were administered antisense oligonucleotides targeting MALAT1 (10 mg / kg and 50 mg / kg) in PBS to a concentration of 10 mg / mL, diluted in PBS to 5 mL / kg, and administered intravenously via tail vein. After 72 hours, blood was collected from the abdominal vena cava of the mice under isoflurane (Japanese Pharmacopoeia, Pfizer Inc.) anesthesia, and the mice were induced by exsanguination. After blood coagulation, serum was prepared by centrifugation and stored frozen (-80°C) until measurement. After exsanguination, the liver, kidneys, fat, skeletal muscle (quadriceps femoris, gastrocnemius), lungs, heart, stomach, jejunum, testes, skin, spleen, and brain were collected and frozen in liquid nitrogen. Homogenization buffer from the Maxwell RSC simplyRNA Tissue Kit was added to frozen tissue, and the tissue was disrupted using a multi-bead shocker. RNA was purified according to the protocol described in the kit. Reactions from RT onward were performed using duplicates, with RNA amounts ranging from 50 to 500 ng per reaction. Knockdown activity was expressed as a percentage of Malat1 expression inhibition, based on the ratio of Malat1 to GAPDH in the vehicle group. The standard error was calculated by determining the individual value from the average of the duplicates. The results are shown in Tables 9 and 10.

[0360] Table 9 Malat1 knockdown rate (%) in each organ after administration of 50 mg / kg Table 10 Malat1 knockdown rate (%) in each organ after administration of 10 mg / kg The sequence of the antisense oligonucleotide used is as follows: G(X)T(X)T(X)cactgaatG(X) (same as sequence number 5 in Table 5 above). Here, lowercase letters represent each nucleic acid base of DNA, T(X), C(X), and G(X) represent the artificial nucleic acid species containing thymine, the artificial nucleic acid species containing 5-methylcytosine, and the artificial nucleic acid species containing guanosine, respectively, and all phosphate bonds are phosphorothioates.

[0361] As is clear from Tables 9 and 10, ALNA[Ms] exhibited potent target gene knockdown activity in many organs (liver, kidney, skeletal muscle, lung, heart, stomach, jejunum, testes, and adipose tissue) compared to the known ALNA[Me]. Furthermore, ALNA[2Pym] exhibited potent target gene knockdown activity in specific organs (heart, jejunum, testes, and adipose tissue) compared to the known ALNA[Me]. Additionally, ALNA[ipU] showed comparable target gene knockdown activity in the liver to ALNA[Me], but exhibited significantly stronger target gene knockdown activity in the lungs and spleen. Since various immune cells accumulate in the spleen, antisense oligonucleotides containing ALNA[ipU] are expected to act on immune cells that are thought to have low penetration rates with conventional nucleic acid drugs. Furthermore, ALNA[ipU] is expected to have potent therapeutic effects on the lungs and immune system while reducing toxicity in the liver.

[0362] Example 150 MALAT1 knockdown activity test in central nervous system tissues, liver, and kidney after intraventricular administration A 7-week-old C57BL / 6J (male, Charles River, Japan) was fixed to a stereotactic device under isoflurane anesthesia and laid on a warming mat. The scalp was incised to expose the skull. After confirming the location of the bregma, a hole was drilled in the skull 1-2 mm around the upper left ventricle (1.0 mm to the left and 0.4 mm posterior to the bregma) using a dental electric drill. A 27-gauge needle was inserted into the skull at the 1 mm position, and a single dose of MALAT1-targeting antisense oligonucleotide (5 μg / 10 μL / head), prepared in physiological saline at a concentration of 5 μg / 10 μL, was administered at a flow rate of 2 μL / min for 5 minutes using a microinfusion pump attached to the needle. The hole in the skull was then sealed with Belfast medical cement (Mutsumi Chemical Industry), the incision was sutured, and gentamicin ointment 0.1% (Takada Pharmaceutical) was applied to prevent infection. 72 hours after administration, blood was collected from the abdominal vena cava of the mice under isoflurane anesthesia, and they were euthanized by exsanguination. After blood coagulation, serum was obtained by centrifugation and stored frozen (-30°C) until measurement. After exsanguination, the brain, spinal cord, kidneys, and liver were collected. For the brain, the skull and spine were separated after euthanasia, and the brain was removed using a Brain slicer for sagittal section preparation. Using Matrices (RBM-2000S, BioResearch Center Co., Ltd.), the brain was thinly sectioned to a thickness of approximately 2 mm from the midline toward the left hemisphere. From these sections, the olfactory bulb, cerebral cortex, hippocampus, striatum, and cerebellum were extracted. The remaining portion of the section, after removing these five areas, was also collected as a composite region including the brainstem. The spinal cord was divided at T13, and two sections were collected: the brain side of T13 (hereinafter referred to as the proximal spinal cord) and the section from T13 to L5 (hereinafter referred to as the distal spinal cord). The collected organs were immersed in RNA later (Invitrogen) and stored at -30°C. The organs and QIAzol Lysis Reagent (QIAGEN) were added to a tube, crushed using a multi-bead shocker, and mixed with chloroform (Junsei Chemical).The aqueous layer was recovered from this mixture by centrifugation, and RNA was purified from this aqueous layer according to the protocol described in the RNeasy 96 Universal Tissue Kit (QIAGEN). From the RT reaction onward, the amount of RNA per reaction was 2 to 7 ng. Knockdown activity was expressed as the inhibition rate of MALAT1 expression in percent, based on the amount ratio of MALAT1 to GAPDH in the vehicle group. The standard error was calculated based on individual values. Table 11 shows the MALAT1 knockdown rate (%) in each central tissue, liver, and kidney after administration of 5 μg / head. The sequence of the antisense oligonucleotide used is as follows: G(X)T(X)T(X)cactgaatG(X)C(X) (same as sequence number 5 in Table 5 above). Here, lowercase letters represent each nucleic acid base of DNA, T(X), C(X), and G(X) represent the artificial nucleic acid species containing thymine, the artificial nucleic acid species containing 5-methylcytosine, and the artificial nucleic acid species containing guanosine, respectively, and all phosphate bonds are phosphorothioates.

[0363] As is clear from Table 11, ALNA[Ms], ALNA[mU], and ALNA[Oxz] exhibited potent target gene knockdown activity in each central tissue compared to the known ALNA, ALNA[Me].

[0364] The amino-crosslinked artificial nucleic acid (ALNA) of the present invention can be used in the production of novel artificial nucleic acid oligomers. Furthermore, oligomers containing the amino-crosslinked artificial nucleic acid of the present invention have potent target gene knockdown activity in specific organs and can be used as nucleic acid drugs.

[0365] Sequence IDs 1-6 represent DNA oligonucleotides. Sequence IDs 7-8 represent RNA oligonucleotides.

Claims

1. General formula I: indicates the point of attachment to the 2'-amino group; R ７ and R ８ are each independently a hydrogen atom, a C optionally substituted with one or more substituents, １－６ an alkyl group, optionally substituted with one or more substituents; ２－６ alkenyl group, optionally substituted with one or more substituents; ２－６ A is an alkynyl group or an aromatic group optionally substituted with one or more substituents; A is an aromatic group; M is a C group optionally substituted with one or more substituents; １－６ and a sulfonyl group substituted with one substituent selected from the group consisting of an alkyl group and an aromatic group optionally substituted with one or more substituents.] or a salt thereof.

2. The compound according to claim 1, or a salt thereof, wherein B is adeninyl optionally having one or more protecting groups, guaninyl optionally having one or more protecting groups, cytosinyl optionally having one or more protecting groups, 5-methylcytosinyl optionally having one or more protecting groups, or uracilyl optionally having one or more protecting groups.

3. R １ , R ２ , R ３ and R ４ The compound according to claim 1 or 2, wherein each independently represents a hydrogen atom; and m is 1, or a salt thereof.

4. X is a group represented by formula (II-1); and R ７ and R ８ are each independently a hydrogen atom, C optionally substituted with one or more substituents １－６ The compound according to any one of claims 1 to 3, or a salt thereof, wherein the aryl group is an alkyl group or an aromatic group optionally substituted with one or more substituents.

5. R ７ and R ８ are each independently a hydrogen atom, C optionally substituted with one or more substituents １－３ The compound according to claim 4, or a salt thereof, which is an alkyl group.

6. R ７ and R ８ The compound according to claim 5, or a salt thereof, wherein one of the groups is a hydrogen atom and the other is a methyl group.

7. R ７ and R ８ The compound according to claim 5, or a salt thereof, wherein one of the groups is a hydrogen atom and the other is an isopropyl group.

8. The compound according to any one of claims 1 to 3, or a salt thereof, wherein X is a group represented by formula (II-2); and A is a 5- or 6-membered heteroaryl group containing one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, optionally substituted with one or more substituents.

9. A is a 5- or 6-membered heteroaryl group containing two or three heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents, and each of the substituents may independently be substituted with one or more halogen atoms. １－３ alkyl group, halogen atom, and one or more C １－３ The compound according to claim 8, or a salt thereof, which is selected from the group consisting of amino groups optionally substituted with alkyl groups.

10. The compound according to claim 9, or a salt thereof, wherein the 5- or 6-membered heteroaryl group is selected from the group consisting of a triazolyl group, an oxadiazolyl group, a thiadiazolyl group, a pyrimidinyl group, and a pyrazinyl group, each of which may be substituted with one or more substituents.

11. The compound according to claim 10, or a salt thereof, wherein the triazolyl group optionally substituted with one or more substituents is a 1,5-dimethyl-1,2,4-triazol-3-yl group.

12. The compound according to claim 10, or a salt thereof, wherein the oxadiazolyl group optionally substituted with one or more substituents is a 5-methyl-1,2,4-oxadiazol-3-yl group.

13. The compound according to claim 10, or a salt thereof, wherein the thiadiazole group optionally substituted with one or more substituents is a 3-methyl-1,2,4-thiadiazol-5-yl group.

14. X is a group represented by formula (II-3); and M is a C group optionally substituted with one or more substituents. １－６ The compound according to any one of claims 1 to 3, or a salt thereof, which is a sulfonyl group substituted with one substituent selected from the group consisting of an alkyl group and an aryl group optionally substituted with one or more substituents.

15. The compound according to claim 14, or a salt thereof, wherein M is a sulfonyl group substituted with one substituent selected from the group consisting of a methyl group and a phenyl group.

16. R ６ is a hydrogen atom or a DMTr group, and R ５ is a hydrogen atom or -P(O(CH ２ ) ２ CN) (N(iPr) ２ 16. The compound according to any one of claims 1 to 15, or a salt thereof, wherein 17. The following compounds: 3-[[(1R,4R,6R,7S)-4-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-6-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-methylsulfonyl-5-oxa-2-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate; N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-purin-6-yl]benzamide; 3-[[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopronylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-5-(benzenesulfonyl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl)oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxo-pyrimidin-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(methylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate; (1R,3R,4R,7S)-3-(6-benzamidopurin-9-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-methyl-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxopyrimidin-1-yl)-1-[[bis(4-methoxyphenyl)phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; [9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(isopropylcarbamoyl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-2-(2-methylpropanoylamino)purin-6-yl]N,N-diphenylcarbamate; (1R,3R,4R,7S)-3-(6-benzamidopurin-9-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N-isopropyl-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; (1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; (1R,3R,4R,7S)-3-(4-benzamido-5-methyl-2-oxo-pyrimidin-1-yl)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-N,N-dimethyl-2-oxa-5-azabicyclo[2.2.1]heptane-5-carboxamide; 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-pyrimidin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; 1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purin-2-yl]-N,N-dimethyl-6-formamidine; N'-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide; 3-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-pyrimidin-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile;N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrimidin-4-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-[4-(trifluoromethyl)pyrimidin-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanethoxy-(diisopropylamino)phosphanyl]oxy-5-[4-(trifluoromethyl)pyrimidin-2-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidin-2-yl)-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(5-chloropyrimidin-2-yl)-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-pyrimidin-4-yl]benzamide;3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[6-(dimethylamino)pyrimidin-4-yl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamine)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanothoxy-(diisopropylamino)phosphanyl]oxy-5-[(6-dimethylamino)pyrimidin-4-yl]-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-[2-(dimethylamino)pyrimidin-4-yl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-[2-(dimethylamino)pyrimidin-4-yl]-7-hydroxy-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-pyrazin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile;N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-pyrazin-2-yl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-5-(1,5-dimethyl-1,2,4-triazol-3-yl)-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazol-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazol-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purin-2-yl]-N,N-dimethyl-formamidine N-[9-(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(1,5-dimethyl-1,2,4-triazol-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]purin-6-yl]benzamide;3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-(5-methyl-1,2,4-oxadiazol-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenylmethoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(5-methyl-1,2,4-oxadiazol-3-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; 3-[[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-3-(5-methyl-2,4-dioxo-pyrimidin-1-yl)-5-(3-methyl-1,2,4-thiadiazol-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-7-yl]oxy-(diisopropylamino)phosphanyl]oxypropanenitrile; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-(3-methyl-1,2,4-thiadiazol-5-yl)-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]benzamide; N-[1-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-5-methyl-2-oxo-pyrimidin-4-yl]dihydropyrimidin-2-one;N'-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purin-2-yl]-N,N-dimethylformamidine; N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-[2-cyanoethoxy-(diisopropylamino)phosphanyl]oxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl] -6-oxo-1H-purin-2-yl]-2-methyl-propanamide; and N-[9-[(1R,3R,4R,7S)-1-[[bis(4-methoxyphenyl)-phenyl-methoxy]methyl]-7-hydroxy-5-methylsulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-yl]-6-oxo-1H-purin-2-yl]-2-methyl-propanamide; 18. General formula (I'): represents a point of attachment to the 2'-amino group; A represents an aromatic group containing one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents; M represents a C group which may be substituted with one or more substituents; １－６ and a sulfonyl group substituted with one substituent selected from the group consisting of an alkyl group and an aromatic group optionally substituted with one or more substituents.] or a salt thereof.

19. The oligonucleotide compound of claim 18, or a salt thereof, wherein B is adeninyl optionally having one or more protecting groups, guaninyl optionally having one or more protecting groups, cytosinyl optionally having one or more protecting groups, 5-methylcytosinyl optionally having one or more protecting groups, or uracilyl optionally having one or more protecting groups.

20. R １ , R ２ , R ３ and R ４ 20. The oligonucleotide compound according to claim 18 or 19, or a salt thereof, wherein: each independently represents a hydrogen atom; and m is 1.

21. X is a group represented by formula (II'-1); and R ７ and R ８ are each independently a hydrogen atom, C optionally substituted with one or more substituents １－６ The oligonucleotide compound according to any one of claims 18 to 20, or a salt thereof, wherein the aryl group is an alkyl group or an aromatic group optionally substituted with one or more substituents.

22. R ７ and R ８ are each independently a hydrogen atom, C optionally substituted with one or more substituents １－３ 22. The oligonucleotide compound of claim 21, or a salt thereof, which is an alkyl group.

23. R ７ and R ８ 23. The oligonucleotide compound according to claim 22, or a salt thereof, wherein one of is a hydrogen atom and the other is a methyl group.

24. R ７ and R ８ 24. The oligonucleotide compound according to claim 23, or a salt thereof, wherein one of is a hydrogen atom and the other is an isopropyl group.

25. The oligonucleotide compound or salt thereof according to any one of claims 18 to 20, wherein X is a group represented by formula (II'-2); and A is a 5- or 6-membered heteroaryl group containing one or more heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, optionally substituted with one or more substituents.

26. A is a 5- or 6-membered heteroaryl group containing 2 or 3 heteroatoms, including at least two nitrogen atoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms, which may be substituted with one or more substituents, and each of the substituents may independently be substituted with one or more halogen atoms. １－３ alkyl group, halogen atom, and one or more C １－３ 26. The oligonucleotide compound according to claim 25, or a salt thereof, wherein the amino group is selected from the group consisting of an amino group optionally substituted with an alkyl group.

27. The oligonucleotide compound of claim 26, or a salt thereof, wherein the 5- or 6-membered heteroaryl group is selected from the group consisting of a triazolyl group, an oxadiazolyl group, a thiadiazolyl group, a pyrimidinyl group, and a pyrazinyl group, each optionally substituted with one or more substituents.

28. The oligonucleotide compound or a salt thereof according to claim 27, wherein the triazolyl group optionally substituted with one or more substituents is a 1,5-dimethyl-1,2,4-triazol-3-yl group.

29. The oligonucleotide compound or a salt thereof according to claim 27, wherein the oxadiazolyl group optionally substituted with one or more substituents is a 5-methyl-1,2,4-oxadiazol-3-yl group.

30. The oligonucleotide compound or a salt thereof according to claim 27, wherein the thiadiazolyl group optionally substituted with one or more substituents is a 3-methyl-1,2,4-thiadiazol-5-yl group.

31. X is a group represented by formula (II'-3); and M is a C optionally substituted with one or more substituents. １－６ The oligonucleotide compound or a salt thereof according to any one of claims 18 to 20, which is a sulfonyl group substituted with one substituent selected from the group consisting of an alkyl group and an aryl group optionally substituted with one or more substituents.

32. The compound according to any one of claims 18 to 31, or a salt thereof, wherein M is a sulfonyl group substituted with one substituent selected from the group consisting of a methyl group and a phenyl group.

33. The sulfurized oligonucleotide according to any one of claims 1 to 32, or a salt thereof, in which at least one of the internucleotide phosphate bonds is a phosphorothioate bond.