Chiral PNAs with Constrained Open-Chain Backbones

  • Roberto Corradini
  • Tullia Tedeschi
  • Stefano Sforza
  • Rosangela Marchelli
Part of the Methods in Molecular Biology book series (MIMB, volume 1050)


Chiral open-chain PNAs have been shown to have improved properties in terms of control of helical handedness, DNA affinity, sequence selectivity, and cellular uptake. They can be synthesized either using preformed chiral monomers or by means of a submonomeric strategy. The former is preferred when only a stereogenic center is present at C-5, whereas for PNA-bearing substituents at C-2, the submonomeric approach is preferred, since racemization, generally occurring during the solid-phase synthesis, can be minimized by this procedure. Here we describe the protocols for the synthesis of PNA oligomers containing C-2- or C-5- (or both) modified monomers and a GC method for checking the optical purity of C-2-modified PNAs.

Key words

Stereochemistry Chiral PNA Submonomeric strategy Optical purity Solid-phase synthesis 

Acronym List




Carboxymethyl nucleobase














N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride


O-(Benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate




4-methyl benzhydrylamine




Trifluoroacetic acid


Trifluoromethanesulfonic acid



This work was supported by the Italian Ministry of University and Research (MIUR) with the national projects PRIN 2007 and PRIN 2009.


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Copyright information

© Springer Science+Business Media, New York 2014

Authors and Affiliations

  • Roberto Corradini
    • 1
  • Tullia Tedeschi
    • 2
  • Stefano Sforza
    • 2
  • Rosangela Marchelli
    • 1
  1. 1.Department of ChemistryUniversity of ParmaParmaItaly
  2. 2.Department of Food ScienceUniversity of ParmaParmaItaly

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