Diethylhydrogensilyl-Cyclic Diethylsilylene Derivatives in Gas Chromatography : Mass Spectrometry of Prostanoids. IV. : 11-Dehydrothromboxane B₂

抄録

Gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) properties of 11-dehydrothromboxane B₂ (11-dehydro-TXB₂) methyl ester-11-n-propylamide-15-diethylhydrogensilyl (DEHS)-9, 12-cyclic diethylsilylene (DES) derivatives were studied. The methylene unit (MU) value of this derivative was 35.17, being 5.7 higher than that of the 11-dehydro-TXB₂ methyl ester-bis-trimethylsilyl ether derivative. The mass spectrum of this derivative was characterized by the ion at m-z 368, which consisted of the fragment of the DES ring and the α-side chain. The major fragmentations were directed by fission of the DES group to give silicon atom-containing ions, inducating that the DES ring takes a leading part in the formation of characteristic ions. Other fragmentations common to the prostanoid derivatives were losses of an ethyl radical from the DAHS or DES group, a C₅H₁₁ hydrocarbon fragment and diethylhydrogensilanol. The fragmentation mechanisms are briefly discussed.