title: New strategies for the synthesis of unmodified and modified oligonucleotides.
abstract: In this paper, our recent studies on the synthesis of unmodified and modified oligonucleotides are comprehensively reviewed. We have developed a new synthetic strategy using TrS, a new 5'-protecting group, that enabled us to reduce one of the steps previously required for DNA synthesis. The "activated phosphite method" without base protection could provide a new tool for the synthesis of DNA oligomers involving base-labile functional groups such as N-acylated nucleobases capable of Watson-Crick base pairing. This new method was successfully applied to the synthesis of oligodeoxynucleotides incorporating cytosine N-oxide or adenine N-oxide that could not be synthesized by the current methods. Furthermore, several approaches we recently developed for the synthesis of several kinds of 2'-O-modified RNA oligomers will be reported.
authors.affiliation: Department of Life Science, Tokyo Institute of Technology, 4259 Nagatsuta, Midoriku, Yokohama, 226-8501, Japan. msckine@bio.titech.ac.jp
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Sekine
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ohkubo
authors.forename: Kohji
authors.initials: K
authors.lastname: Seio
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives / Q000737:chemistry; D001671:Biochemistry / Q000379:methods; D003497:Cyclic N-Oxides / Q000737:chemistry*; D003596:Cytosine / Q000031:analogs & derivatives* / Q000737:chemistry; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D003497:Cyclic N-Oxides; D009838:Oligodeoxyribonucleotides; C030755:adenine-N-oxide; D003596:Cytosine; D000225:Adenine