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bioRxiv · 10.1101/2022.04.24.489320

Direct N-Me Aziridination Reaction Enables Pinpointing C=C Bonds in Lipids with Mass Spectrometry

Feng, G.·Gao, M.·Fu, R.·Wan, Q.·Wang, T.·Zhang, Z.·Chen, S.
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Abstract

The biological functions of lipids largely depend on their chemical structures. The position of C=C bonds is an essential attribute that determines the structures of unsaturated lipids. Here, we developed a new type of chemical derivatization method for C=C bond using aziridination reaction. This new cyclization method for the C=C bonds in lipids based on the direct N-Me aziridination reaction of olefins using N-methyl-O-tosylhydroxylamine (TsONHCH3) as the aminating reagent. When combined with the tandem MS analysis, this novel activation approach for C=C bonds enables the accurate identification their positions in different kinds of unsaturated lipids. Furthermore, an integrated workflow has been established for comprehensively identifying the C=C bond positional isomers of lipids in complicated biological sample. This work provided a new chemical approach for the structural lipidomics.

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Feng, G., Gao, M., Fu, R., Wan, Q., Wang, T., Zhang, Z., Chen, S.. 2022-04-25. Direct N-Me Aziridination Reaction Enables Pinpointing C=C Bonds in Lipids with Mass Spectrometry. https://doi.org/10.1101/2022.04.24.489320

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