Synthesis of macrocyclic peptide nucleic acid derivatives via intramolecular chemical ligation

Solid-phase synthesis and thermal denaturation study of cyclic PNAs targeting the HIV-1 TAR RNA loop

Cyclic PNAs targeting the HIV-1 TAR RNA loop have been synthesized following a convenient solid-phase strategy which allows on-resin cyclisation. UV-monitored thermal denaturation studies demonstrate that these cyclic PNAs are able to strongly interact with their TAR RNA target, very likely through the formation of a six-base pair stable complex, involving the TAR RNA loop.

Convergent synthesis of peptide nucleic acids by native chemical ligation

[reaction: see text] A convergent strategy for synthesizing long contiguous PNA by a native chemical ligation-like technique of PNA segment couplings is presented. This approach required the synthesis of a new PNA-monomer featuring a 1-amino-2-thiol group. It is shown that the additional mercaptomethyl group leaves the hybridization properties of PNA ligation products unaffected. Furthermore, rapid and efficient fluorescence labeling of the ligation products is demonstrated.