Zur lokalisierrung funktioneller gruppen mit hilfe der massenspektrometrie—IX : 17 β-hydroxy-androstan-3,6-dione, 3-hydroxy-androstan-6,17-dione und 3,17β-dihydroxy-androstan-6-one

Mass spectra of steroids with a 3β-configurated hydroxy-group and a keto-function in position 6 are characterized in the case of cis-connection of the A/B-ring system by a key ion at M-71, whereas if the rings A and B are trans-connected the production of a key ion of mass 139 is preferred. The substitution of the 3-hydroxy group by a keto-function alters the main fragmentation routes: In the case of cis-connection of the A/B-ringsystem a key ion corresponding to the loss of C-3 to C-7 is observed, while by trans-connection of the A/B-ringsystem C-1 and C-2 are lost as C₂H₅-radical.