DETERMINATION OF STRUCTURES OF SPHINGOLIPID BASES BY COMBINED GAS CHROMATOGRAPHY-MASS SPECTROMETRY

Analysis of the N-acetyl-O-trimethylsilyl derivatives of sphingolipid bases by combined gas chromatography-mass spectrometry gives detailed information about the chemical structures of these substances. In addition to defining the chain length and degree of unsaturation of an unknown base, mass spectral data provide information to classify the base as a sphinganine or 4-hydroxysphinganine type. The positions of double bonds in the aliphatic chains of these bases can be determined by mass spectrometry of the osmium tetroxide oxidation products of N-acetyl derivatives after conversion of the products into trimethylsilyl derivatives. Characteristic mass spectral fragmentations at positions of vicinal trimethylsilyloxy groups give conclusive evidence for the location of double bonds in the parent base. © 1969, American Chemical Society. All rights reserved.