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activity in the standard coagulation assay for activated
References and notes
partial thromboplastin time (APTT) and prothrombin
time (PT), as well as the more sensitive dilute PT (dPT)
with diluted thromboplastin reagent.10 Surprisingly,
compounds 27 and 29, which in the enzyme assay are
approximately equipotent to 22 are around 16 times
more potent than this compound in the more stringent
and predictive dPT antithrombotic assay, as well as
being more potent in the APTT and PT assays (Table
5).10 This lack of clear correlation between enzyme
inhibition and potency in coagulation assays has previ-
ously been reported.5
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ꢀ
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The same compounds were also tested in human S9 liver
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In conclusion, we have developed a new class of potent
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Acknowledgements
We would like to thank Astrid Sihorsch, Marga
€
Kammerer-Dienst, Lynn Bayer, Dirk Timme, Norbert
Laub and Stefan Engel for their excellent technical
assistance.