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Synthesis and biophysical studies of PNA and chimeric PNA-DNA antisense oligomers with five atom linkages

Khirud Gogoi


The amide linkage being shorter than the natural phosphate linkage, an additional atom is introduced into oligodeoxyribonucleosides (ODNs) with sugar–thioacetamide backbone that show very good RNA recognition properties. Also an a/b-peptide backbone oligonucleotide comprising natural a-amino acids alternating with a b-amino acid component derived from thymidine sequence specifically recognizes and binds to deoxy- and ribo-oligoadenylates in triplex mode. The highly versatile “click-chemistryâ€, the reaction between azide and alkyne groups is employed to generate the conjugates of peptides with DNA oligonucleotides and their different chemically modifications including peptide nucleic acids (PNAs) and thioacetamido nucleic acids (TANA).


Antisense Oligonucleotides; phosphate backbone modification; Thioacetamido Nucleic Acid; Peptide Nucleic Acids; Peptide-oligonucleotide conjugates; Click Chemistry

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