Synthesis and self-pairing property of peptide nucleic acid-functionalized
monomer
Ruttiyakorn Donthongkwa, Tirayut Vilaivan and Voravee P. Hoven*
Organic Synthesis Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn
University, Bangkok, Thailand
*e-mail: [email protected]
Nucleobase-induced supramolecular interactions have gained much attention as
potential non-covalent driving force for generating interesting nano-assembled structures.
Peptide nucleic acid has been shown to recognize another strand of complementary nucleic
acid following the highly specific Watson-Crick base pairing rules. In this research,
tetra(ethylene oxide) functionalized with peptide nucleic acid at both ends of the chain
(PNA-TEO) was first prepared via copper(I)-catalyzed alkyne-azidecycloaddition (CuAAC)
click reaction of tetra(ethylene oxide)-di(alkyne) (TEO-di(alkyne)) and azide-modified PNA
(N3-PNA). Pyrrolidinyl peptide nucleic acid with (2′R,4′S)-prolyl/(1S,2S)-2aminocyclopentanecarboxylic backbone (epi-acpcPNA) having alternate CG sequence was
chosen according to its ability to undergo self-pairing. The success of the synthesis of the
PNA-TEO was confirmed by MALDI-TOF mass spectrometry. Its self-pairing property and
secondary structure were investigated by UV-vis and circular dichroism (CD) spectroscopy,
respectively. It is anticipated that this developed epi-acpcPNA-based functionalized
molecules can be used as a building block of novel self-assembled nanostructures that can be
regulated by temperature control or by the presence/absence of a DNA template.
Keywords: Supramolecular polymer; Peptide nucleic acid; Tetra(ethylene glycol)