Table 1

Mass spectrometric data from LC-ESI/MS analyses of pooled human liver microsomal incubates (20 μM, 20 min)

Conditions1-aComponentIons Observed1-b1-cm/z (% relative intensity)
[M-H] (Containing 1 14C Atom)M+H+ (Containing 1 14C Atom)Fragment A (Containing 1 14C Atom)Fragment A - H2O (Containing 1 14C Atom)Additional Fragments with Rel. Int. ≥5%
Positive ions, 29-V collision offsetCA324  (100)1-d 143  (92)1-d
D-DHD1314  (100)1-d 177  (16)159  (17)
D-DHD2314  (100)1-d
DOL296  (88)1-d 143  (100)1-d 119  (11)
DHD1328  (100)1-d 177  (8)1-d 159  (9)1-d
DHD2328  (100)1-d 159  (3)
OL310  (94)1-d 143  (100)1-d 119  (10)
D280  (47)1-d 143  (100)1-d 121 (6), 93 (7)
terbinafine294  (39)1-d 143  (100)1-d 93  (7)
Negative ions, 10-V collision offsetNA173  (100)
  • 1-a Offset voltage applied in the ion source region (between skimmer and transfer-octopole) for declustering and collision-induced fragmentation.

  • 1-b Parent drug 88% [14C]-labeled; ions containing the label appearing two mass units higher than without label.

  • 1-c Fragment A: cleavage of benzylic type C-N bond with charge retention on the aromatic ring system.

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  • 1-d Accompanying minor signal of the all-12C isotopomer observed two mass units lower.