Letters
Journal of Medicinal Chemistry, 2004, Vol. 47, No. 27 6661
Table 3. Pharmacokinetic Properties of Compound 13 in
Sprague-Dawley Rats
potent Src and Bcr-Abl kinase inhibitory activity was
identified. Analogues demonstrated broad spectrum
antiproliferative activity against hematological and solid
tumor cell lines originating in breast, prostate, and colon
tissue. Compound 13, a picomolar inhibitor of Src and
Bcr-Abl kinase, was orally active in a K562 xenograft
model of chronic myelogenous leukemia, demonstrating
tumor regressions at multiple dose levels. On the basis
of its favorable in vivo efficacy and pharmacokinetic
profile, 13 has been advanced into clinical trials.
parameter
unit
iv dosea
oral dosea
dose
Cmax
Tmax
AUCtot
t1/2
MRT
Cl
mg/kg
10
13.2 (-)
-
13.9 (4.6)
3.3 (0.9)
4.1 (1.2)
26.4 (7.8)
6.3 (2.2)
-
10
µM
0.5 (0.2)
2.2 (3.2)
3.8 (2.1)
3.1 (0.3)
6.7 (0.6)
-
h
µM‚h
h
h
mL/min/mg
L/kg
%
Vss
Fpo
-
27
a Data reported as an average of three animals with associated
standard deviations in parentheses.
Acknowledgment. We thank A. Donald Crews,
Christopher Ellis, Christopher Sheng, Laurence I. Wu,
and Yufen Zhao for synthetic chemistry support and
Bethanne Warrack and Discovery Analytical Sciences
for compound characterization efforts.
Supporting Information Available: Characterization
data for compounds 1 through 12. Full experimental proce-
dures and characterization data for compound 13. Detailed
description of pharmacokinetic assays. This material is avail-
References
(1) O′Dwyer, M. E.; Mauro, M. J.; Druker, B. J. STI571 as a targeted
therapy for CML. Cancer Invest. 2003, 21, 429-438.
(2) Frame, M. C. Src in cancer: deregulation and consequences for
cell behaviour. Biochim. Biophys. Acta 2002, 1602, 114-130.
(3) Wityak, J.; Das, J.; Moquin, R. V.; Shen, Z.; Lin, J.; Chen, P.;
Doweyko, A. M.; Pitt, S.; Pang, S.; Shen, D. R.; Fang, Q.; De
Fex, H. F.; Schieven, G. L.; Kanner, S. B.; Barrish, J. C.
Discovery and initial SAR of 2-amino-5-carboxamidothiazoles as
inhibitors of the Src-family kinase p56lck. Bioorg. Med. Chem.
Lett. 2003, 13, 4007-4010.
(4) Chen, P.; Norris, D.; Das, J.; Spergel, S. H.; Wityak, J.; Leith,
L.; Zhao, R.; Chen, B.-C.; Pitt, S.; Pang, S.; Shen, D. R.; Zhang,
R.; De Fex, H. F.; Dowyeko, A. M.; McIntyre, K. W.; Shuster, D.
J.; Behnia, K.; Schieven, G. L.; Barrish, J. C. Identification of
BMS-334864 as a novel, potent and orally active Src-family
kinase p56lck inhibitor. Bioorg. Med. Chem. Lett., in press.
(5) Antiproliferative activities were determined based on tetrazolium
dye conversion following 72 h drug exposure. Details of the assay
and culture conditions for the tumor cell lines are contained in
the following reference: Lee, F. Y. F.; Borzilleri, R. M.; Fairchild,
C. R.; Kim, S. H.; Long, B. H.; Reventos-Suarez, C.; Vite, G. D.;
Rose, W. C.; Kramer, R. A. BMS-247550: A novel epothilone
Figure 3. In vivo antitumor activity of compound 13 versus
K562 xenografts in nude mice. Drug formulated as a solution
in citric acid buffer at pH 4.6.
and mean residence time (MRT). The measured oral
bioavailability (Fpo) in this study was 27%. In conjunc-
tion with the mouse 4 h oral exposure data, it was
concluded that 13 had a pharmacokinetic profile ap-
propriate for continued advancement into in vivo ef-
ficacy studies. A summary of the PK parameters from
the rat study is contained in Table 3.
The in vivo activity of 13 was evaluated in a K562
xenograft assay in nude mice (Figure 3). Tumor cells
were implanted subcutaneously and staged to ap-
proximately 300 mg prior to two cycles of oral drug
administration on a 5 day on and 2 day off schedule.
Following once daily doses of either 5 or 50 mg/kg,
compound 13 showed partial tumor regressions after
one treatment cycle and complete disappearance of the
tumor mass by the end of drug treatment. No toxicity
(animal deaths, lack of weight gain) was observed in
either cohort of animals. Thus, it was determined that
13 possessed potent in vivo activity and a high safety
margin in this animal model of CML. The in vivo
activity of 13 in imatinib-resistant12 and imatinib-
refractory models and solid tumor xenografts will be
reported in separate communications.
analogue with
a mode of action similar to paclitaxel but
possessing superior antitumor efficacy. Clin. Cancer Res. 2001,
7, 1429-1437.
(6) Begtrup, M.; Hansen, L. B. New methods for the introduction
of substituents into thiazoles. Acta Chem. Scand. 1992,46, 372-
383.
(7) Saito, J.; Tamura, T.; Morishima, N. JP 50,089,344, 1975.
(8) Ueno, K.; Kinoene, M.; Minami, T. JP 43,005,394, 1968.
(9) Commercially available from Sigma-Aldrich Corporation.
(10) Nagar, B.; Bornmann, W. G.; Pellicena, P.; Schindler, T.; Veach,
D. R.; Miller, W. T.; Clarkson, B.; Kuriyan, J. Crystal structures
of the kinase domain of c-Abl in complex with the small molecule
inhibitors PD173955 and imatinib (STI-571). Cancer Res. 2002,
62, 4236.
(11) Huron, D. R.; Gorre, M. E.; Kraker, A. J.; Sawyers, C. L.; Rosen,
N.; Moasser, M. M. A novel pyridopyrimidine inhibitor of Abl
kinase is a picomolar inhibitor of Bcr-Abl-driven K562 cells and
is effective against STI571-resistant Bcr-Abl mutants. Clin.
Cancer. Res. 2003, 9, 1267-1273.
(12) Shah, N. P.; Tran, C.; Lee, F. Y.; Chen, P.; Norris, D.; Sawyers,
C. L. Overriding imatinib resistance with a novel Abl kinase
inhibitor. Science 2004, 305, 399-401.
(13) Xu, W.; Doshi, A.; Lei, M.; Eck, M. J.; Harrison, S. C. Crystal
structures of c-Src reveal features of its autoinhibitory mecha-
nism. Mol. Cell 1999, 3, 629-638.
In conclusion, a novel series of 2-(aminopyridyl)-
and 2-(aminopyrimidinyl)thiazole-5-carboxamides with
JM049486A