Synthesis of Nucleobase-Functionalized Morpholino Monomers

  • Bappaditya Nandi
  • Sankha Pattanayak
  • Sibasish Paul
  • Jayanta Kundu
  • Surajit SinhaEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1973)


Morpholino antisense oligonucleotides are used as routine tools in developmental biology to investigate gene function during early embryogenesis. These chemically modified oligos contain morpholine ring connected with phosphorodiamidate linkages as backbone but carry unmodified nucleobases. In this chapter, we describe the methods to further modify the nucleobases using palladium-catalyzed cross-coupling reactions. The key reactions used are halogenations of the nucleobases in suitable position and subsequent Pd-catalyzed Sonogashira and Suzuki reactions. The sequential synthetic steps are described in detail in this chapter, and the examples are shown in tables.

Key words

Morpholino oligonucleotides Morpholino monomers Functionalized nucleobases Halogenation Pd-catalyzed cross-coupling 



This work was supported by the Council of Scientific and Industrial Research (CSIR), New Delhi, by a grant no. 02(0204)/14/EMR-II.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Bappaditya Nandi
    • 1
  • Sankha Pattanayak
    • 1
  • Sibasish Paul
    • 1
  • Jayanta Kundu
    • 1
  • Surajit Sinha
    • 1
    Email author
  1. 1.Department of Organic ChemistryIndian Association for the Cultivation of ScienceJadavpurIndia

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