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bioRxiv · 10.1101/2025.09.26.678795

Towards One-Step and Universal Synthesis of Hypermodified Uracil Nucleosides: acp3U and cmnm5U

Mejdr, I.·Mejdr, E.·Heinickel, L.·Carell, T.
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Abstract

Hypermodified nucleosides have been recently in the center of scientific attention. They represent a unique group of nucleosides with an alternated structure, such as the addition of functional groups or amino acids. Their distinctive structures and positions in RNAs are crucial for the processes of translation and stability. High demand of oligonucleotides bearing those hypermodified nucleobases lead us to the development of a single step synthesis of acp3U phosphoramidite, as acp3U has been recognized as an important molecule for the structural integrity of tRNA and native immunity. We also present a novel synthesis of cmnm5U phosphoramidite and its incorporation into an oligonucleotide from a universal starting material, allowing a transformation into at least two other hypermodified nucleosides.

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Mejdr, I., Mejdr, E., Heinickel, L., Carell, T.. 2025-09-26. Towards One-Step and Universal Synthesis of Hypermodified Uracil Nucleosides: acp3U and cmnm5U. https://doi.org/10.1101/2025.09.26.678795

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