(A) The kinetics of entry into the cells and degradation of
AL776 inside the cells were monitored using HPLC analysis. NIH3T3-Her14
(EGFR transfected) cells were treated with 25 μM of AL776 for 1h,
2h, 6h, 24h and 48h, after which the cells and the corresponding
extracellular media were collected and processed according to the
procedure described in the Materials and Method section. The area under
the curve (AUC) for the AL776 peak was determined and its percentage
compared with all the other peaks was calculated and plotted.
(B) A representative spectrum obtained from liquid
chromatography (LC)-mass spectrometry (MS) analysis in cells treated
with AL776 for 48h is shown with m/z = 462 (AL621), m/z = 488
(dasatinib) and m/2z = 517 (AL776). (C) The kinetics of
AL776 hydrolysis in the plasma of CD-1 mice injected with 80 mg/kg of
the drug was monitored 5, 15 and 30 min post-administration. LC-MS
chromatograms at different time points with m/z values for intact AL776
and its metabolites are shown: m/z = 462 for AL621, m/z = 562 for
AL621-L (succinic acid linked-AL621), m/z = 488 for dasatinib, m/z = 588
for dasatinib-L (succinic acid linked-dasatinib), m/2z = 516 for
AL776.