Abstract:
The possibilities and limitations of the mass-spectrometric method in the solution of problems concerning the location of the double bond in steroids have been demonstrated for a large number of such compounds containing the double bond in various positions in the polycyclic system and in the side chain. The mass spectra of Δ1-, Δ2-, Δ4-, Δ5-, Δ7-, Δ13-, Δ16-, Δ22-, Δ23-, and Δ24-steroids, in which the diagnostic fragments are due to the dissociation of at least one allylic bond, are the most characteristic. The double bonds in other positions in the steroid skeleton either do not initiate specific decomposition processes at all, or inhibit processes characteristic of the corresponding saturated analogues, or cause the appearance of fragments the driving force responsible for the formation of which is obscure. A separate section of the review deals with aromatic and diene steroids. The bibliography includes 86 references.