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Updated: Jul 10, 2026

Constructing Cyclic Peptides Using an On-Tether Sulfonium Center
Published on: September 28, 2022
Solid-phase synthesis and properties of chiral peptide nucleic acids bearing cationic side chains
Hirotake Harada1, Sho Funayama, Yoshiaki Shoji
1Department of Medical Genome Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
Abstract:
A novel chiral peptide nucleic acid, ornithine-based nucleobase-linked polyamide (ONA), aimed to hybrid with a DNA duplex to form triplexes, was designed and synthesized. The chiral monomers composed of the ornithine-based backbone and the serine-derived side chains were synthesized in stereocontrolled manners. The diastereopure oligomers were synthesized by a solid-phase method using the diastereopure monomers. Highly cross-linked polystyrene (HCP) resin was employed as a solid support to minimize the aggregation of the oligomer which was suspected to occur during the chain elongation. By the use of new solid-phase method, homo-thymine ONA oligomers were synthesized in good yields. The ONA hexamer was found to form a triplex with the dsDNA in a sequence specific manner.
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