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PubMed · 15772418

N-acyl migration in ceramides.

Helena Van Overloop·Gerd Van der Hoeven·Paul P Van Veldhoven
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Abstract

Upon exposure of truncated ceramides, such as N-acetyl-sphingenine, and long-chain ceramides to moderate acidic conditions, three derivatives are formed. Two of them turned out to be O-acylated sphingenine, 1-O- and 3-O-acyl-sphingenine, and the other was identified as sphingenine. Truncated dihydroceramides (e.g., N-acetyl- and N-hexanoyl-sphinganine) also show this type of rearrangement, which is therefore not related to the presence of the allylic hydroxy group or to the length of the N-acyl chain. Of particular concern is the fact that the O-acylated compounds, which can be considered sphingoid base analogs, can be formed in chloroform or chloroform-methanol mixtures upon storage. For long-term storage, methanol or dichloromethane is the preferred solvent. A procedure to document the presence/formation of such O-acylated sphingoid bases in ceramide solutions in the picomole range, based on reversed-phase chromatography after derivatization of their amino group with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate, is presented.

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AcidsAcylationCeramidesChromatography, High Pressure LiquidChromatography, Thin LayerHydrogen-Ion ConcentrationMolecular StructureJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

Helena Van Overloop, Gerd Van der Hoeven, Paul P Van Veldhoven. 2005-01-16. N-acyl migration in ceramides.. https://doi.org/10.1194/jlr.d400034-jlr200

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