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Synthesis and Evaluation of Neutral Phosphate Triester Backbone-Modified siRNAs.

ABSTRACT: Two unsymmetrical dinucleotide phosphate triesters were synthesized via transesterification from tris(2,2,2-trifluoroethyl) phosphate. The protected triesters were phosphytilated to generate phosphoramidites for solid-phase oligonucleotide synthesis. Neutral phenylethyl phosphate-modified short-interfering RNAs (siRNAs) were synthesized and evaluated for their gene-silencing ability, siRNA strand selection, and resistance to nucleases. These backbone-modified phosphate triester siRNAs offer many improvements compared to natural unmodified siRNAs.

SUBMITTER: Tsubaki K

PROVIDER: S-EPMC7357222 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Hydrogen bond formation between the naturally modified nucleobase and phosphate backbone.

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