Studies on trimethylsilyl derivatives of 1‐alkyl‐2‐acylglycerols by gas‐liquid chromatography mass spectrometry

Trimethylsilyl derivatives of 1‐hexadecyl‐2‐decanoyl‐, ‐hexadecanoyl‐ and ‐octadecenoylglycerols and 1‐octadecyl‐2‐decanoyl‐, ‐hexadecanoyl‐ and ‐octadecenoylglycerols as well as 1,2‐dihexadecanoylglycerol were analysed by a gas chromatograph mass spectrometer system. The following points are characteristic of the fragmentation pattern of these 1‐alkyl‐2‐acyl derivatives: (1) in the spectra of alkyl acyl derivatives, ions at [M – 15] + and [M – 90] + ˙ are 14 mass units less than those of the corresponding diacyl derivatives; (2) the base peak is m / e 130; (3) alkyl acyl derivatives show fragments due to one acyl group instead of the two acyl groups of diacyl derivatives; (4) ions at m / e 314 and 342, [R 1 0 + 73] + ˙, are characteristic of the trimethylsilyl derivatives of hexadecyl‐ and octadecylglycerols, respectively; (5) the ion [M – R 1 0] + is present, but the complementary alkoxy ion is absent.