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PubMed · 16002284

Trichloroacetaldehyde modified oligonucleotides.

Hans Gaus·Phil Olsen·Kent Van Sooy·Claus Rentel·Brett Turney·Kathleen L Walker·James V McArdle·Daniel C Capaldi
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Abstract

Some commercial batches of dichloroacetic acid (DCA) contain traces of chloral (trichloroacetaldehyde). Using such DCA to effect detritylation during solid-phase oligonucleotide synthesis results in the formation of a family of process impurities in which the atoms of chloral (Cl3CCHO) are incorporated between the 5'-oxygen and phosphorus atoms of an internucleotide linkage. The structure was elucidated by HPLC with UV and MS detection, digestion of the oligonucleotide, synthesis of model compounds, and 1H and 31P NMR spectroscopy. By understanding the chemistry behind its formation, we are now able to limit levels of this impurity in synthetic oligonucleotides by limiting chloral in DCA.

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Chloral HydrateChromatography, High Pressure LiquidChromatography, Ion ExchangeDrug ContaminationMass SpectrometryMolecular StructureOligonucleotidesJournal Article

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Hans Gaus, Phil Olsen, Kent Van Sooy, Claus Rentel, Brett Turney, Kathleen L Walker, James V McArdle, Daniel C Capaldi. 2005-09-15. Trichloroacetaldehyde modified oligonucleotides.. https://doi.org/10.1016/j.bmcl.2005.06.018

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