Influence of 11-trimethylsilyloxy- or 11-hydroxy-substituents on the electron-impact-induced fragmentation of trimethylsilyl derivatives of some androstanols
The mass spectra of the trimethylsilyl derivatives of some androstanes containing an 11-hydroxy-substituent exhibit several prominent and characteristic ions containing the trimethylsilyl group. The mechanisms of formation of these ions have been investigated with the aid of high-resolution mass spectrometry and deuterium, 18O, and perdeuteriotrimethylsilyl labelling. Ions of the same mass and composition occurring in the spectra of different compounds do not necessarily have the same structure, but their formation is dependent on the presence of the 11-trimethylsilyloxy-function.