Base-Modified Oligonucleotides With Increased Duplex Stability

Pyrazolo[3,4-d] Pyrimidines Replacing Purines
  • Frank Seela
  • Yang He
  • Junlin He
  • Georg Becher
  • Rita Kröschel
  • Matthias Zulauf
  • Peter Leonard
Part of the Methods in Molecular Biology book series (MIMB, volume 288)


Oligonucleotides incorporating 8-aza-7-dazapurines (pyrazolo[3,4-d]pyrimidines) were synthesized. The corresponding nucleosides were prepared and were converted into phosphoramidites. The oligonucleotide duplex stability was studied and was compared to that of the parent compounds containing the canonical purine nucleosides. The presence of 7-halogeno or 7-alkynyl substituents increases the duplex stability significantly.

Key Words

Nucleosides phosphoramidites oligonucleotides glycosylation solid-phase synthesis base modification pyrazolo[3,4-d]pyrimidines 8-aza-7-deazapurines base pair stability Tm values hybridization harmonization of base pair stability 


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Copyright information

© Humana Press Inc. 2005

Authors and Affiliations

  • Frank Seela
    • 1
  • Yang He
    • 1
  • Junlin He
    • 1
  • Georg Becher
    • 1
  • Rita Kröschel
    • 1
  • Matthias Zulauf
    • 1
  • Peter Leonard
    • 1
  1. 1.Laboratorium für Organische und Bioorganische Chemie, Institut für ChemieUniversität OsnabrückOsnabrückGermany

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