The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
Takeshi Imanishi - One of the best experts on this subject based on the ideXlab platform.
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Design, synthesis, and properties of 2',4'-BNA(NC): a bridged Nucleic Acid Analogue.
Journal of the American Chemical Society, 2008Co-Authors: S. M. Abdur Rahman, Satoshi Obika, Sayori Seki, Haruhisa Yoshikawa, Kazuyuki Miyashita, Takeshi ImanishiAbstract:The novel bridged Nucleic-Acid Analogue 2‘,4‘-BNANC (2‘-O,4‘-C-aminomethylene bridged Nucleic Acid), containing a six-membered bridged structure with an N−O linkage, was designed and synthesized efficiently, demonstrating a one-pot intramolecular NC bond-forming key reaction to construct a perhydro-1,2-oxazine ring (11 and 12). Three monomers of 2‘,4‘-BNANC (2‘,4‘-BNANC[NH], [NMe], and [NBn]) were synthesized and incorporated into oligonucleotides, and their properties were investigated and compared with those of 2‘,4‘-BNA (LNA)-modified oligonucleotides. Compared to 2‘,4‘-BNA (LNA)-modified oligonucleotides, 2‘,4‘-BNANC congeners were found to possess: (i) equal or higher binding affinity against an RNA complement with excellent single-mismatch discriminating power, (ii) much better RNA selective binding, (iii) stronger and more sequence selective triplex-forming characters, and (iv) immensely higher nuclease resistance, even higher than the Sp-phosphorthioate Analogue. 2‘,4‘-BNANC-modified oligonucleot...
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2 4 bna nc a novel bridged Nucleic Acid Analogue with excellent hybridizing and nuclease resistance profiles
Nucleosides Nucleotides & Nucleic Acids, 2007Co-Authors: S Abdur M Rahman, Satoshi Obika, Sayori Seki, Kazuyuki Miyashita, Kazushige Utsuki, Takeshi ImanishiAbstract:Oligonucleotides modified with 2 ′,4 ′-BNA NC (N-H)/(N-Me) monomers exhibited excellent hybridizing and nuclease resistance properties. Duplex and triplex thermal stabilities were greatly enhanced by incorporating 2′,4′-BNA NC (N-H) and (N-Me) monomers and nuclease resistance was tremendously higher than that of natural oligonucleotide.
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2′,4′-BNA NC : A Novel Bridged Nucleic Acid Analogue with Excellent Hybridizing and Nuclease Resistance Profiles
Nucleosides nucleotides & nucleic acids, 2007Co-Authors: S. M. Abdur Rahman, Satoshi Obika, Sayori Seki, Kazuyuki Miyashita, Kazushige Utsuki, Takeshi ImanishiAbstract:Oligonucleotides modified with 2 ′,4 ′-BNA NC (N-H)/(N-Me) monomers exhibited excellent hybridizing and nuclease resistance properties. Duplex and triplex thermal stabilities were greatly enhanced by incorporating 2′,4′-BNA NC (N-H) and (N-Me) monomers and nuclease resistance was tremendously higher than that of natural oligonucleotide.
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synthesis and chemical properties of a novel 2 4 bridged Nucleic Acid Analogue with a seven membered cyclic carbamate structure
Nucleic acids symposium series (2004), 2007Co-Authors: Masaru Nishida, Satoshi Obika, Tetsuya Kodama, Takeshi ImanishiAbstract:BNA We designed and synthesized a novel bridged Nucleic Acid (BNA) with N-type sugar conformation, possessing a seven-membered cyclic carbamate structure (2',4'-(CNC) monomer). The monomer shows interesting chemical properties, such as prompt migration of the carbamate bridge from the 2'-to the 3'-position and consequent conformational change of the furanose moiety. These chemical behaviors of 2',4'-BNA(CNC) were investigated by (1)H-NMR analysis, and the structure of the compound after migration was confirmed by X-ray crystallographic analysis.
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n methyl substituted 2 4 bnanc a highly nuclease resistant Nucleic Acid Analogue with high affinity rna selective hybridization
Chemical Communications, 2007Co-Authors: Kazuyuki Miyashita, Satoshi Obika, Sayori Seki, S Abdur M Rahman, Takeshi ImanishiAbstract:Oligonucleotides modified with a novel BNA Analogue, 2′, 4′-BNANC[N–Me], were synthesized, and in comparison to 2′,4′-BNA (LNA), have similarly high RNA affinity, better RNA selectivity and much higher resistance to nuclease degradation, suggesting that the novel BNA Analogue may be particularly useful for antisense approaches.
Satoshi Obika - One of the best experts on this subject based on the ideXlab platform.
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Design, synthesis, and properties of 2',4'-BNA(NC): a bridged Nucleic Acid Analogue.
Journal of the American Chemical Society, 2008Co-Authors: S. M. Abdur Rahman, Satoshi Obika, Sayori Seki, Haruhisa Yoshikawa, Kazuyuki Miyashita, Takeshi ImanishiAbstract:The novel bridged Nucleic-Acid Analogue 2‘,4‘-BNANC (2‘-O,4‘-C-aminomethylene bridged Nucleic Acid), containing a six-membered bridged structure with an N−O linkage, was designed and synthesized efficiently, demonstrating a one-pot intramolecular NC bond-forming key reaction to construct a perhydro-1,2-oxazine ring (11 and 12). Three monomers of 2‘,4‘-BNANC (2‘,4‘-BNANC[NH], [NMe], and [NBn]) were synthesized and incorporated into oligonucleotides, and their properties were investigated and compared with those of 2‘,4‘-BNA (LNA)-modified oligonucleotides. Compared to 2‘,4‘-BNA (LNA)-modified oligonucleotides, 2‘,4‘-BNANC congeners were found to possess: (i) equal or higher binding affinity against an RNA complement with excellent single-mismatch discriminating power, (ii) much better RNA selective binding, (iii) stronger and more sequence selective triplex-forming characters, and (iv) immensely higher nuclease resistance, even higher than the Sp-phosphorthioate Analogue. 2‘,4‘-BNANC-modified oligonucleot...
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2 4 bna nc a novel bridged Nucleic Acid Analogue with excellent hybridizing and nuclease resistance profiles
Nucleosides Nucleotides & Nucleic Acids, 2007Co-Authors: S Abdur M Rahman, Satoshi Obika, Sayori Seki, Kazuyuki Miyashita, Kazushige Utsuki, Takeshi ImanishiAbstract:Oligonucleotides modified with 2 ′,4 ′-BNA NC (N-H)/(N-Me) monomers exhibited excellent hybridizing and nuclease resistance properties. Duplex and triplex thermal stabilities were greatly enhanced by incorporating 2′,4′-BNA NC (N-H) and (N-Me) monomers and nuclease resistance was tremendously higher than that of natural oligonucleotide.
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2′,4′-BNA NC : A Novel Bridged Nucleic Acid Analogue with Excellent Hybridizing and Nuclease Resistance Profiles
Nucleosides nucleotides & nucleic acids, 2007Co-Authors: S. M. Abdur Rahman, Satoshi Obika, Sayori Seki, Kazuyuki Miyashita, Kazushige Utsuki, Takeshi ImanishiAbstract:Oligonucleotides modified with 2 ′,4 ′-BNA NC (N-H)/(N-Me) monomers exhibited excellent hybridizing and nuclease resistance properties. Duplex and triplex thermal stabilities were greatly enhanced by incorporating 2′,4′-BNA NC (N-H) and (N-Me) monomers and nuclease resistance was tremendously higher than that of natural oligonucleotide.
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synthesis and chemical properties of a novel 2 4 bridged Nucleic Acid Analogue with a seven membered cyclic carbamate structure
Nucleic acids symposium series (2004), 2007Co-Authors: Masaru Nishida, Satoshi Obika, Tetsuya Kodama, Takeshi ImanishiAbstract:BNA We designed and synthesized a novel bridged Nucleic Acid (BNA) with N-type sugar conformation, possessing a seven-membered cyclic carbamate structure (2',4'-(CNC) monomer). The monomer shows interesting chemical properties, such as prompt migration of the carbamate bridge from the 2'-to the 3'-position and consequent conformational change of the furanose moiety. These chemical behaviors of 2',4'-BNA(CNC) were investigated by (1)H-NMR analysis, and the structure of the compound after migration was confirmed by X-ray crystallographic analysis.
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n methyl substituted 2 4 bnanc a highly nuclease resistant Nucleic Acid Analogue with high affinity rna selective hybridization
Chemical Communications, 2007Co-Authors: Kazuyuki Miyashita, Satoshi Obika, Sayori Seki, S Abdur M Rahman, Takeshi ImanishiAbstract:Oligonucleotides modified with a novel BNA Analogue, 2′, 4′-BNANC[N–Me], were synthesized, and in comparison to 2′,4′-BNA (LNA), have similarly high RNA affinity, better RNA selectivity and much higher resistance to nuclease degradation, suggesting that the novel BNA Analogue may be particularly useful for antisense approaches.
Jesper Wengel - One of the best experts on this subject based on the ideXlab platform.
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Locked Nucleic Acid as a novel class of therapeutic agents
RNA biology, 2009Co-Authors: Rakesh N. Veedu, Jesper WengelAbstract:Locked Nucleic Acid (LNA) is a Nucleic Acid Analogue with unprecedented binding affinity and excellent specificity toward complementary RNA and DNA oligonucleotides. The remarkable properties of LNA have led to applications within various gene silencing strategies both in vitro and in vivo. In the present review, we highlight the uses of LNA for regulation of gene expression with emphasis on RNA targeting.
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Locked Nucleic Acid (LNA): High affinity targeting of RNA for diagnostics and therapeutics.
Drug discovery today. Technologies, 2005Co-Authors: Sakari Kauppinen, Birte Vester, Jesper WengelAbstract:Locked Nucleic Acid (LNA) is a Nucleic Acid Analogue containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA mimicking sugar conformation. This conformational restriction results in unprecedented hybridization affinity towards complementary single stranded RNA and thus, makes LNA uniquely suited for mimicking RNA structures and sequence specific targeting of RNA in vitro or in vivo. The focus of this paper is on LNA-antisense, LNA-modified siRNA (siLNA), and detection and analysis of microRNAs by LNA-modified oligonucleotide probes.
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lna locked Nucleic Acid high affinity targeting of complementary rna and dna
Biochemistry, 2004Co-Authors: Birte Vester, Jesper WengelAbstract:Locked Nucleic Acid (LNA) is a Nucleic Acid Analogue containing one or more LNA nucleotide monomers with a bicyclic furanose unit locked in an RNA mimicking sugar conformation. LNA oligonucleotides display unprecedented hybridization affinity toward complementary single-stranded RNA and complementary single- or double-stranded DNA. Structural studies have shown that LNA oligonucleotides induce A-type (RNA-like) duplex conformations. The wide applicability of LNA oligonucleotides for gene silencing and their use for research and diagnostic purposes are documented in a number of recent reports, some of which are described herein.
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NMR studies of fully modified locked Nucleic Acid (LNA) hybrids: solution structure of an LNA:RNA hybrid and characterization of an LNA:DNA hybrid.
Bioconjugate chemistry, 2003Co-Authors: Katrine E. Nielsen, Jesper Wengel, Jill Rasmussen, Ravindra Kumar, Jens Peter Jacobsen, Michael B. PetersenAbstract:LNA is a bicyclic Nucleic Acid Analogue that contains one or more 2‘-O,4‘-C methylene linkage(s), which effectively locks the furanose ring in a C3‘-endo conformation. We report here the NMR soluti...
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LNA: a versatile tool for therapeutics and genomics
Trends in biotechnology, 2003Co-Authors: Michael Nebeling Petersen, Jesper WengelAbstract:Locked Nucleic Acid (LNA) is a Nucleic Acid Analogue that displays unprecedented hybridization affinity towards complementary DNA and RNA. Structural studies have shown LNA to be an RNA mimic, fitting seamlessly into an A-type duplex geometry. Several reports have revealed LNA as a most promising molecule for the development of oligonucleotide-based therapeutics. For example, Tat-dependent transcription and telomerase activity have been efficiently suppressed by LNA oligomers, and efficient cleavage of highly structured RNA has been achieved using LNA-modified DNAzymes ('LNAzyme'). Furthermore, convincing examples of the application of LNA to Nucleic Acid diagnostics have been reported, including high capturing efficiencies and unambiguous scoring of single-nucleotide polymorphisms.
Mitsuaki Sekiguchi - One of the best experts on this subject based on the ideXlab platform.
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synthesis and properties of a novel bridged Nucleic Acid Analogue 5 amino 3 5 bna
Nucleosides Nucleotides & Nucleic Acids, 2005Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:An oligonucleotide P3′⇉N5′ phosphoramidate (5′-amino-DNA) attracts much attention because of its potential for application to DNA sequencing; however, its ability to hybridize with complementary st...
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Synthesis and properties of a novel bridged Nucleic Acid Analogue, 5'-amino-3',5'-BNA.
Nucleosides nucleotides & nucleic acids, 2005Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:An oligonucleotide P3'-->N5' phosphoramidate (5'-amino-DNA) attracts much attention because of its potential for application to DNA sequencing; however, its ability to hybridize with complementary strands is low. To overcome this drawback of the 5-amino-DNA, we have designed and successfully synthesized a novel Nucleic Acid Analogue having a P3'-->N5' phosphoramidate linkage and a constrained sugar moiety, 5'-amino-3'-C,5'-N-methylene bridged Nucleic Acid (5'-amino-3',5'-BNA). The binding affinity of the 5'-amino-3',5'-BNA towards complementary DNA and RNA strands was investigated by UV melting experiments. The melting temperature (Tm) of the duplex comprising the 5'-amino-3',5'-BNA and its complementary strand was much higher than that of the duplex containing the corresponding 5-amino-DNA.
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Synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a P3′→N5′ phosphoroamidate linkage, 5′-amino-3′, 5′-BNA
Nucleic Acids Symposium Series, 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
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synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a p3 n5 phosphoroamidate linkage 5 amino 3 5 bna
Nucleic acids symposium series (2004), 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
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Synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a P3'-->N5' phosphoroamidate linkage, 5'-amino-3', 5'-BNA.
Nucleic acids symposium series (2004), 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
Roongjang Somjing - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and properties of a novel bridged Nucleic Acid Analogue, 5'-amino-3',5'-BNA.
Nucleosides nucleotides & nucleic acids, 2005Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:An oligonucleotide P3'-->N5' phosphoramidate (5'-amino-DNA) attracts much attention because of its potential for application to DNA sequencing; however, its ability to hybridize with complementary strands is low. To overcome this drawback of the 5-amino-DNA, we have designed and successfully synthesized a novel Nucleic Acid Analogue having a P3'-->N5' phosphoramidate linkage and a constrained sugar moiety, 5'-amino-3'-C,5'-N-methylene bridged Nucleic Acid (5'-amino-3',5'-BNA). The binding affinity of the 5'-amino-3',5'-BNA towards complementary DNA and RNA strands was investigated by UV melting experiments. The melting temperature (Tm) of the duplex comprising the 5'-amino-3',5'-BNA and its complementary strand was much higher than that of the duplex containing the corresponding 5-amino-DNA.
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synthesis and properties of a novel bridged Nucleic Acid Analogue 5 amino 3 5 bna
Nucleosides Nucleotides & Nucleic Acids, 2005Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:An oligonucleotide P3′⇉N5′ phosphoramidate (5′-amino-DNA) attracts much attention because of its potential for application to DNA sequencing; however, its ability to hybridize with complementary st...
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Synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a P3′→N5′ phosphoroamidate linkage, 5′-amino-3′, 5′-BNA
Nucleic Acids Symposium Series, 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
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synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a p3 n5 phosphoroamidate linkage 5 amino 3 5 bna
Nucleic acids symposium series (2004), 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
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Synthesis and properties of a novel bridged Nucleic Acid Analogue bearing a P3'-->N5' phosphoroamidate linkage, 5'-amino-3', 5'-BNA.
Nucleic acids symposium series (2004), 2004Co-Authors: Mitsuaki Sekiguchi, Satoshi Obika, Roongjang Somjing, Takeshi ImanishiAbstract:We have designed and successfully synthesized a novel bridged Nucleic Acid Analogue with a P3'-->N5' phosphoramidate linkage, 5'-amino-3',5'-BNA. X-ray crystallographic analysis demonstrated that the 5'-amino-3',5'-BNA had C1-exo-O4-endo sugar puckering and a constrained gamma dihedral angle of 22.8 degrees. The oligonucleotides containing 5'-amino-3',5'-BNA exhibited strong binding affinity towards complementary strands. In addition, the 5'-amino-3',5'-BNA oligonucleotide was easily hydrolyzed at its phosphoramidate linkage under mild Acidic conditions.
