Abstract: A method of reducing the level of a transcription product in a cell comprising contacting with the cell a composition comprising a double-stranded nucleic acid complex comprising a first nucleic acid strand annealed to a second nucleic acid strand, wherein: (i) the first nucleic acid strand hybridizes to the transcription product and comprises (a) a region consisting of at least 4 consecutive nucleotides that are recognized by RNase H when the strand is hybridized to the transcription product, (b) one or more nucleotide analogs located on 5? terminal side of the region, (c) one or more nucleotide analogs located on 3? terminal side of the region and (d) a total number of nucleotides and nucleotide analogs ranging from 8 to 35 nucleotides and (ii) the second nucleic acid strand comprises (a) nucleotides and optionally nucleotide analogs and (b) at least 4 consecutive RNA nucleotides.

Abstract: Disclosed are bridged nucleosides and nucleotides. The nucleosides of the present invention have a 2?,4?-bridged structure and are represented by formula I below: An oligonucleotide containing a 2?,4?-bridged artificial nucleotide of the present invention has a binding affinity for single-stranded RNA comparable to that of known 2?,4?-BNA/LNA and higher nuclease resistance than LNA. In particular, since the oligonucleotide has a much higher binding affinity for single-stranded RNA than S-oligo, it is expected that the oligonucleotide is applicable to nucleic acid drugs.

Abstract: Disclosed are bridged nucleosides and nucleotides. The nucleosides of the present invention have a 2?,4?-bridged structure and are represented by formula I below: An oligonucleotide containing a 2?,4?-bridged artificial nucleotide of the present invention has a binding affinity for single-stranded RNA comparable to that of known 2?,4?-BNA/LNA and higher nuclease resistance than LNA. In particular, since the oligonucleotide has a much higher binding affinity for single-stranded RNA than S-oligo, it is expected that the oligonucleotide is applicable to nucleic acid drugs.

Abstract: Disclosed are double-stranded antisense nucleic acid complexes that can efficiently alter the processing of RNA in a cell via an antisense effect, and methods for using the same. One method comprises contacting with the cell a double-stranded nucleic acid complex comprising: a first nucleic acid strand annealed to a second nucleic acid strand, wherein: the first nucleic acid strand comprises (i) nucleotides independently selected from natural DNA nucleotides, modified DNA nucleotides, and nucleotide analogs, (ii) no regions that have 4 or more consecutive natural DNA nucleotides, (iii) the total number of natural DNA nucleotides, modified DNA nucleotides, and nucleotide analogs in the first nucleic acid strand is from 8 to 100, and (iv) the first nucleic acid strand is capable of hybridizing to RNA inside of the cell; and the second nucleic acid strand comprises nucleotides independently selected from natural RNA nucleotides, modified RNA nucleotides, and nucleotide analogs.

Abstract: The present invention provides compounds shown by the formula: wherein Y1-Y2 is S(?O)2—NR6, NR6—S(?O)2 or the like, R6 is a hydrogen atom, substituted or unsubstituted alkyl or the like, Bx is a nucleic acid base moiety, Z1 and Z2 are each independently, a hydrogen atom, a hydroxyl protecting group or a reactive phosphorus group, R1 to R5 are each independently, a hydrogen atom, halogen, cyano, substituted or unsubstituted alkyl or the like, and n is an integer of 0 to 3, or salts thereof, that are novel nucleosides or nucleotides that can be useful as materials for synthesizing nucleic acid pharmaceuticals.

Abstract: An oligonucleotide or a pharmacologically acceptable salt thereof of the present invention contains a compound represented by formula I or II or a salt thereof, and at least one of nucleoside structures represented by formula I? or II?. According to the present invention, provided is a nucleic acid molecule for oligonucleotides having high binding affinity and specificity to a target nucleic acid, and exhibiting high nuclease resistance.

Abstract: An object of the present invention is to provide an oligonucleotide useful as a therapeutic agent for dyslipidemia that has excellent binding affinity to the PCSK9 gene as well as stability and safety. The oligonucleotide of the present invention contains a sugar-modified nucleoside, the sugar-modified nucleoside has a bridging structure between 4?-position and 2?-position, and the oligonucleotide can bind to the human PCSK9 gene. Also, the present invention provides a therapeutic agent for dyslipidemia containing the oligonucleotide as an active ingredient, and the therapeutic agent preferably contains a bioabsorbable material as a carrier. The bioabsorbable material is preferably atelocollagen or peptide gel.

Abstract: The oligonucleotide of the present invention includes a sugar-modified nucleoside, the sugar-modified nucleoside has a cross-linked structure between 4?-position and 2?-position, and the oligonucleotide is capable of binding to the apolipoprotein C-III gene. According to the present invention, an oligonucleotide useful as a therapeutic agent for hyperlipidemia that is excellent in binding affinity to the apolipoprotein C-III gene, stability and safety is provided.

Abstract: A method of reducing the level of a transcription product in a cell comprising contacting with the cell a composition comprising a double-stranded nucleic acid complex comprising a first nucleic acid strand annealed to a second nucleic acid strand, wherein: (i) the first nucleic acid strand hybridizes to the transcription product and comprises (a) a region consisting of at least 4 consecutive nucleotides that are recognized by RNase H when the strand is hybridized to the transcription product, (b) one or more nucleotide analogs located on 5? terminal side of the region, (c) one or more nucleotide analogs located on 3? terminal side of the region and (d) a total number of nucleotides and nucleotide analogs ranging from 8 to 35 nucleotides and (ii) the second nucleic acid strand comprises (a) nucleotides and optionally nucleotide analogs and (b) at least 4 consecutive RNA nucleotides.

Abstract: The present invention provides an 18F-labeled azide compound usable in the Huisgen reaction which enables 18F-labeling although only a small quantity of alkyne compound is available as a counterpart substrate, more specifically the 18F-labeled azide compound enabling the PET to be applied to peptides or oligonucleotides and enabling the 18F-labeling of any sites of oligonucleotide other than the 5? end or 3? end thereof, a reagent for 18F-labeling, and a method for 18F-labeling of an alkyne compound using the same.

Abstract: It is an object of the present invention to provide a novel molecule for antisense therapies which is not susceptible to nuclease degradation in vivo and has a high binding affinity and specificity for the target mRNAs and which can efficiently regulate expression of specific genes. The novel artificial nucleoside of the present invention has an amide bond introduced into a bridge structure of 2?,4?-BNA/LNA. The oligonucleotide containing the 2?,4?-bridged artificial nucleotide has a binding affinity for a single-stranded RNA comparable to known 2?,4?-BNA/LNA and has an increased nuclease resistance over LNA. Particularly, it is expected to be applied to nucleic acid drugs because of its much stronger binding affinity for single-stranded RNAs than S-oligo's affinity.

Abstract: An object of the present invention is to provide an oligonucleotide useful as a therapeutic agent for dyslipidemia that has excellent binding affinity to the PCSK9 gene as well as stability and safety. The oligonucleotide of the present invention contains a sugar-modified nucleoside, the sugar-modified nucleoside has a bridging structure between 4?-position and 2?-position, and the oligonucleotide can bind to the human PCSK9 gene. Also, the present invention provides a therapeutic agent for dyslipidemia containing the oligonucleotide as an active ingredient, and the therapeutic agent preferably contains a bioabsorbable material as a carrier. The bioabsorbable material is preferably atelocollagen or peptide gel.

Abstract: It is an object of the present invention to provide a novel molecule for antisense therapies which is not susceptible to nuclease degradation in vivo and has a high binding affinity and specificity for the target mRNAs and which can efficiently regulate expression of specific genes. The novel artificial nucleoside of the present invention has an amide bond introduced into a bridge structure of 2?,4?-BNA/LNA. The oligonucleotide containing the 2?,4?-bridged artificial nucleotide has a binding affinity for a single-stranded RNA comparable to known 2?,4?-BNA/LNA and has an increased nuclease resistance over LNA.

Abstract: [OBJECT] The present invention provides an 18F-labeled azide compound usable in the Huisgen reaction which enables 18F-labeling although only a small quantity of alkyne compound is available as a counterpart substrate, more specifically the 18F-labeled azide compound enabling the PET to be applied to peptides or oligonucleotides and enabling the 18F-labeling of any sites of oligonucleotide other than the 5? end or 3? end thereof, a reagent for 18F-labeling, and a method for 18F-labeling of an alkyne compound using the same. [SOLVING MEANS] An 18F-labeled azide compound according to the present invention is expressed by the following structural formula 1.

Abstract: Oligonucleotide analogues which have anti-sense or anti-gene activity, as well as in vivo stability, or pharmaceutically acceptable salts thereof. The oligonucleotide analogues have one or more structural units represented by the following formula (1a): provided that when the oligonucleotide has two or more structural units of formula (1a), each B is the same or different, wherein B represents a purin-9-yl group or a 2-oxo-1,2-dihydropyrimidin-1-yl group.

Abstract: A nucleotide analogue compound represented by formula (1) and salts thereof. In formula (1), A represents a direct bond, C1-4 alkylene, etc.; B represents an optionally substituted aromatic heterocyclic groups; and R1, R2, R3 and R4 each represents hydrogen, an amino-protecting group, a hydroxyl-protecting group, a phosphate group, or —P(R7)R8, wherein R7 and R8 each represents hydroxyl, protected hydroxyl, mercapto, protected mercapto, etc. The compounds are useful as nucleotide analogues for producing oligonucleotide analogues useful in an antisense method and for producing intermediates thereof.

Abstract: An oligonucleotide analogue useful for the antisense method, etc., having excellent enzyme resistance, having potent selective binding affinity for single-stranded RNA, and further having an excellent triplex-forming capacity with double-stranded DNA, and a nucleoside analogue useful for its production are provided. Nucleoside analogues, which are compounds of the general formula (I) and salts thereof, and oligonucleotide analogues containing one or more of the nucleoside analogues: where Base is an aromatic heterocyclic group or the like optionally having a substituent; R1, R2 and R3 are each a hydrogen atom, a protective group for an amino group, a protective group for a hydroxyl group, a phosphate group, or —P(R4)R5 [where R4 and R5 are each a hydroxyl group, a protected hydroxyl group, a mercapto group, a protected mercapto group, etc.]; m=0 to 2; and n=1 to 3].

Abstract: Oligonucleotide analogues which have anti-sense or anti-gene activity, as well as in vivo stability, or pharmaceutically acceptable salts thereof. The oligonucleotide analogues have one or more structural units represented by the following formula (1a): provided that when the oligonucleotide has two or more structural units of formula (1a), each B is the same or different, wherein B represents a purin-9-yl group or a 2-oxo-1,2-dihydropyrimidin-1-yl group.

Abstract: An oligonucleotide analogue useful for the antisense method, etc., having excellent enzyme resistance, having potent selective binding affinity for single-stranded RNA, and further having an excellent triplex-forming capacity with double-stranded DNA, and a nucleoside analogue useful for its production are provided. Nucleoside analogues, which are compounds of the general formula (I) and salts thereof, and oligonucleotide analogues containing one or more of the nucleoside analogues: where Base is an aromatic heterocyclic group or the like optionally having a substituent; R1, R2 and R3 are each a hydrogen atom, a protective group for an amino group, a protective group for a hydroxyl group, a phosphate group, or —P(R4)R5 [where R4 and R5 are each a hydroxyl group, a protected hydroxyl group, a mercapto group, a protected mercapto group, etc.]; m=0 to 2; and n=1 to 3].

Abstract: An oligo- or polynucleotide analogue having one or more structures of the general formula where B is a pyrimidine or purine nucleic acid base, or an analogue thereof, is disclosed. The use of this analogue provides an oligonucleotide analogue antisense molecule, which is minimally hydrolyzable with an enzyme in vivo, has a high sense strand binding ability, and is easily synthesized.