title: Oligo-2'-fluoro-2'-deoxynucleotide N3'-->P5' phosphoramidates: synthesis and properties.
abstract: Uniformly modified oligodeoxyribonucleotide N3'-->P5' phosphoramidates containing 2'-fluoro-2'-deoxy-pyrimidine nucleosides were synthesized using an efficient interphase amidite transfer reaction. The 3'-amino group of solid phase-supported 2'-fluoro-2'-deoxynucleoside was used as an acceptor and 5'-diisopropylamino phosphoramidite as a donor of a phosphoramidite group in the tetrazole-catalyzed exchange reaction. Subsequent oxidation with aqueous iodine resulted in formation of an internucleoside phosphoramidate diester. The prepared oligo-2'-fluoro-nucleotide N3'-->P5' phosphoramidates form extremely stable duplexes with complementary nucleic acids: relative to isosequential phosphodiester oligomers, the melting temperature Tm of their duplexes with DNA or RNA was increased approximately 4 or 5 degrees C per modification respectively. Moreover, these compounds are highly resistant to enzymatic hydrolysis by snake venom phosphodiesterase and they are 4-5 times more stable in acidic media (pH 2.2-5.3) than the parent oligo-2'-deoxynucleotide N3'-->P5' phosphoramidates. The described properties of the oligo-2'-fluoronucleotide N3'-->P5' phosphoramidates suggest that they may have good potential for diagnostic and antisense therapeutic applications.
authors: Lynx Therapeutics, Inc, Hayward, CA 94545, USA.
authors: R G
authors: RG
authors: Schultz
authors: S M
authors: SM
authors: Gryaznov
mesh_terms: D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D004247:DNA / Q000737:chemistry*; D017611:Fluorine Compounds / Q000737:chemistry*; D006358:Hot Temperature; D006868:Hydrolysis; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation; D009838:Oligodeoxyribonucleotides / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D012313:RNA / Q000737:chemistry
chemical_list: D017611:Fluorine Compounds; D009838:Oligodeoxyribonucleotides; D011743:Pyrimidines; D012313:RNA; D004247:DNA