The Experts below are selected from a list of 1938 Experts worldwide ranked by ideXlab platform
Hiroaki Sawai - One of the best experts on this subject based on the ideXlab platform.
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duplex stabilizing effect and nuclease resistant property of novel oligonucleotides containing c 2 branched polyamine bearing deoxyinosine derivative
Chemistry Letters, 2002Co-Authors: Kazuo Shinozuka, Masaaki Onodera, Hiroshi Ikeda, Hiroaki SawaiAbstract:Novel Oligodeoxyribonucleotides containing a C-2 branched polyamine-bearing deoxyinosine moiety at either inside-region or the 5′-terminus of the sequence exhibited enhanced nuclease resistant property. Among them, only the oligomers having the modified deoxyinosine residue at inside-region brought about duplex stabilizing effect upon mixing with the complements.
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synthesis of oligodeoxyribonucleotide bearing 2 s alkyl residue and its effect on the duplex stability
ChemInform, 2000Co-Authors: Hiroaki Ozaki, Yuichi Sato, Sadaji Azuma, Hiroaki SawaiAbstract:2'-Deoxy-2'-S-hexyluridine derivative was synthesized from 2,2'-anhydrouridine and 1-hexanethiol and incorporated into an oligodeoxyribonucleotide. The thermal stability of the duplexes formed by the 2'-S-hexyl modified ODN with either the complementary DNA or RNA strand was decreased compared to the unmodified counterparts.
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synthesis of a novel 2 deoxyuridine derivative bearing a cyanomethoxycarbonylmethyl group at c 5 position and its use for versatile post synthetic functionalization of Oligodeoxyribonucleotides
Tetrahedron Letters, 1998Co-Authors: Satoru Kohgo, Kazuo Shinozuka, Hiroaki Ozaki, Hiroaki SawaiAbstract:Abstract A novel 2′-deoxyuridine derivative bearing a cyanomethoxycarbonylmethyl group at the C-5 position (1) was synthesized, and its use was examined as a convertible nucleoside for the versatile post-synthesis functionalization of Oligodeoxyribonucleotides (ODNs). The ODNs containing 1 reacted with primary monoamines such as heptylamine, histamine, and tyramine as well as d- and polyamines under mild conditions, giving the corresponding derivatized ODNs.
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novel c5 substituted 2 deoxyuridine derivatives bearing amino linker arms synthesis incorporation into Oligodeoxyribonucleotides and their hybridization properties
ChemInform, 1995Co-Authors: Hiroaki Ozaki, Akiko Nakamura, Midori A Arai, Masakazu Endo, Hiroaki SawaiAbstract:2′-Deoxyuridine derivatives bearing several kinds of amino-linker arms at C5 position were synthesized from 5-(methoxycarbonylmethyl)-2′-deoxyuridine and ethylenediamine, 1,6-hexanediamine, or tris(2-aminoethyl)amine. The modified nucleosides were incorporated into Oligodeoxyribonucleotides at one or three positions in place of thymidine residues. The thermal stability of the duplexes was investigated. Three incorporations of ethylenediamine or tris(2-aminoethyl)amine at the C5-position increase the duplex stability. The amino-linker arm affected the stability of the duplexes depending on the number of amino groups in the linker arm and the length of the arm. The linker arm improved the nuclease resistance at 5′-side phosphodiester linkage of the modified nucleoside in Oligodeoxyribonucleotides.
Hiroaki Ozaki - One of the best experts on this subject based on the ideXlab platform.
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synthesis of oligodeoxyribonucleotide bearing 2 s alkyl residue and its effect on the duplex stability
ChemInform, 2000Co-Authors: Hiroaki Ozaki, Yuichi Sato, Sadaji Azuma, Hiroaki SawaiAbstract:2'-Deoxy-2'-S-hexyluridine derivative was synthesized from 2,2'-anhydrouridine and 1-hexanethiol and incorporated into an oligodeoxyribonucleotide. The thermal stability of the duplexes formed by the 2'-S-hexyl modified ODN with either the complementary DNA or RNA strand was decreased compared to the unmodified counterparts.
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synthesis of a novel 2 deoxyuridine derivative bearing a cyanomethoxycarbonylmethyl group at c 5 position and its use for versatile post synthetic functionalization of Oligodeoxyribonucleotides
Tetrahedron Letters, 1998Co-Authors: Satoru Kohgo, Kazuo Shinozuka, Hiroaki Ozaki, Hiroaki SawaiAbstract:Abstract A novel 2′-deoxyuridine derivative bearing a cyanomethoxycarbonylmethyl group at the C-5 position (1) was synthesized, and its use was examined as a convertible nucleoside for the versatile post-synthesis functionalization of Oligodeoxyribonucleotides (ODNs). The ODNs containing 1 reacted with primary monoamines such as heptylamine, histamine, and tyramine as well as d- and polyamines under mild conditions, giving the corresponding derivatized ODNs.
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novel c5 substituted 2 deoxyuridine derivatives bearing amino linker arms synthesis incorporation into Oligodeoxyribonucleotides and their hybridization properties
ChemInform, 1995Co-Authors: Hiroaki Ozaki, Akiko Nakamura, Midori A Arai, Masakazu Endo, Hiroaki SawaiAbstract:2′-Deoxyuridine derivatives bearing several kinds of amino-linker arms at C5 position were synthesized from 5-(methoxycarbonylmethyl)-2′-deoxyuridine and ethylenediamine, 1,6-hexanediamine, or tris(2-aminoethyl)amine. The modified nucleosides were incorporated into Oligodeoxyribonucleotides at one or three positions in place of thymidine residues. The thermal stability of the duplexes was investigated. Three incorporations of ethylenediamine or tris(2-aminoethyl)amine at the C5-position increase the duplex stability. The amino-linker arm affected the stability of the duplexes depending on the number of amino groups in the linker arm and the length of the arm. The linker arm improved the nuclease resistance at 5′-side phosphodiester linkage of the modified nucleoside in Oligodeoxyribonucleotides.
Brian T Chait - One of the best experts on this subject based on the ideXlab platform.
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matrix assisted laser desorption mass spectrometry of homopolymer Oligodeoxyribonucleotides influence of base composition on the mass spectrometric response
Journal of Mass Spectrometry, 1993Co-Authors: Klaus Schneider, Brian T ChaitAbstract:Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has the potential for providing a rapid alternative to gel electrophoresis for DNA sequence analysis provided that an intense mass spectrometric response can be obtained from mixtures of DNA fragments containing up to 300 nucleotides. MALDI-MS has not yet proved viable for such analyses because the MS response falls off rapidly for mixed-base DNA fragments containing more than 20–30 nucleotides. Previous studies have demonstrated that base composition is a critical factor in the MALDI-MS response of Oligodeoxyribonucleotides. This paper describes an investigation of the physical roots of the observed influence of base composition on the mass spectrometric response, focusing on homopolymer Oligodeoxyribonucleotides (dT7, dT10, dT18, dT36, dG7, dG10, dG18, dI18 and dU18) and dT5G5. Forty-eight different matrix compounds were tested for their ability to produce laser desorption masses spectra from such homopolymer Oligodeoxyribonucleotides. Considerably stronger mass spectrometric responses were obtained from polydeoxythymidines than from polydeoxyguanosines, polydeoxycytidines and polydeoxyadenosines. Although mass spectral peaks corresponding to dT18 were observed from 20 of the matrices studied, no discernible response was observed for dG18 from any of these matrices. To elucidate the physical basis for origins of the observed differences in response, a number of factors were investigated including the ionization efficiency, the tendency towards fragmentation and the extent to which the Oligodeoxyribonucleotides were incorporated into the matrix crystals. The results of these experiments indicate that low ionization efficiency is not a likely main contributor to the low response to polydeoxyguanosines, fragmentation is a likely main contributor to the low response to polydeoxyguanosines, the overall incorporation of polydeoxyguanosines into matrix crystals is comparable to that for polydeoxythymidines and the exocyclic amino group of guanosine, adenosine and cytidine has a strong inhibitory effect on the mass spectrometric response.
Kaoru Shimada - One of the best experts on this subject based on the ideXlab platform.
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biologically active Oligodeoxyribonucleotides part 12 1 n2 methylation of 2 deoxyguanosines enhances stability of parallel g quadruplex and anti hiv 1 activity
Bioorganic & Medicinal Chemistry Letters, 2000Co-Authors: Makoto Koizumi, Keika Akahori, Toshinori Ohmine, Shinya Tsutsumi, Junko Sone, Toshiyuki Kosaka, Masakatsu Kaneko, Satoshi Kimura, Kaoru ShimadaAbstract:2'-Deoxyguanosine residues of a 3',5'-end-modified hexadeoxyribonucleotide (R-95288) with anti-HIV-1 activity were substituted with N2-methyl-2'-deoxyguanosine (m2dG). These modified Oligodeoxyribonucleotides (ODNs) showed a 2-fold higher activity than R-95288. Also, the CD spectra of these ODNs indicated that the m2dG modification stabilized the tertiary structure of the G-quadruplex.
Kenzo Fujimoto - One of the best experts on this subject based on the ideXlab platform.
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dna photo cross linking using 3 cyanovinylcarbazole modified oligonucleotide with threoninol linker
Organic Letters, 2015Co-Authors: Takashi Sakamoto, Yuya Tanaka, Kenzo FujimotoAbstract:3-Cyanovinylcarbazole modified d-threoninol (CNVD) was incorporated in oligodeoxyribonucleotide and tested for a photo-cross-linking reaction with complementary oligodeoxyribonucleotide. The photoreactivity was 1.8- to 8-fold greater than that of 3-cyanovinylcarbazole modified deoxyribose (CNVK) previously reported. From the results of melting analysis and circular dichroism spectroscopy of the duplexes, the relatively flexible structure of CNVD compared with CNVK might be advantageous for [2 + 2] photocycloaddition between the cyanovinyl group on the CNVD and pyrimidine base in the complementary strand.
