Discovery of potent and specific CXCR3 antagonists

Article abstract of DOI:10.1016/j.bmcl.2011.10.120

The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3 receptor is reported. Compounds were optimized to avoid the formation of active metabolites and time-dependent-inhibitors of CYP3A4. In addition, antagon

Full text of DOI:10.1016/j.bmcl.2011.10.120

Bioorganic & Medicinal Chemistry Letters 22 (2012) 357–362
Contents lists available at SciVerse ScienceDirect
Bioorganic & Medicinal Chemistry Letters
journal homepage: www.elsevier.com/locate/bmcl
Discovery of potent and specific CXCR3 antagonists
⇑
Xiaoqi Chen , Jeff Mihalic, Jeff Deignan, Darin J. Gustin, Jason Duquette, Xiaohui Du, Johann Chan,
Zice Fu, Michael Johnson, An-Rong Li, Kirk Henne, Tim Sullivan, Bryan Lemon, Ji Ma,
Shichang Miao, George Tonn, Tassie Collins, Julio C. Medina
Amgen Inc., 1120 Veterans Boulevard, ASF2-3, South San Francisco, CA 94080, USA
a r t i c l e i n f o
a b s t r a c t
Article history:
The optimization of a series of 8-aza-quinazolinone analogs for antagonist activity against the CXCR3
receptor is reported. Compounds were optimized to avoid the formation of active metabolites and
time-dependent-inhibitors of CYP3A4. In addition, antagonists showed potent against CXCR3 activity
in whole blood and optimized to avoid activity in the chromosomal aberration assay. Compound 25
was identified as having the optimal balance of CXCR3 activity and pharmacokinetic properties across
multiple pre-clinical species, which are reported herein.
Received 3 October 2011
Revised 28 October 2011
Accepted 31 October 2011
Available online 9 November 2011
Keywords:
CXCR3
Ó 2011 Elsevier Ltd. All rights reserved.
Antagonist
Inflammation
Leukocyte migration is a critical step in the pathophysiology of
autoimmune and inflammatory conditions. Recent clinical data
with protein therapeutics such as Raptiva and Tysabri, and with
small molecules such as Gilenya indicates that blockade of T cell
migration into inflammed tissue provides an effective way of treat-
ing inflammatory diseases. CXCR3 is the predominant chemokine
receptor expressed on activated T-cells of Type-1 (Th1) and medi-
ates recruitment and activation of Th1 cells. In addition to Th1
cells, CXCR3 is also expressed on NK cells, B cells and on a fraction
of circulating CD4+ and CD8+ T cells. CXCR3 and its ligands, MIG
(CXCL9), IP-10 (CXCL10), and I-TAC (CXCL11), are upregulated in
several inflammatory diseases including multiple sclerosis,1
inflammatory bowel disease,2 rheumatoid arthritis,3 and solid or-
gan transplant rejection.4 The established clinical utility of inter-
dicting lymphocyte recruitment coupled with strong human
disease association data and compelling pre-clinical data provide
the rationale for proposing blockade of CXCR3-mediated T-cell
recruitment as a therapeutic target with opportunity for develop-
ment in several immunologic inflammatory diseases. Therefore,
we and others have been interested in discovering CXCR3 antago-
nists as potential therapeutics.5
(IC50 = 15 nM), and MIG (IC50 = 36 nM) in vitro. However, daily
doses above 100 mg of AMG 487 resulted in drug accumulation
in humans receiving multiple doses that was not observed in pre-
clinical species. Evaluation of AMG 487 using in vitro and in vivo
preclinical models led to the discovery of a major metabolite,
M1, and a minor metabolite M2 (Fig. 1). M1 was found to be a cir-
culating active metabolite in human, while M2 was found to be a
time-dependent inhibitor (TDI) of CYP3A4.7 M2 is believed to be
responsible for the accumulation seen in humans with AMG 487.
We have previously reported that replacement of the pyridyl
methyl group with an ethyl sulfone group, as shown in compound
3, increases CXCR3 affinity.8 Thus, we decided to focus on analogs
bearing this moiety since they would also avoid the formation of
the pyridine N-oxide metabolite.
In order to address the potential formation of a phenol metab-
olite similar to M2 new cores were explored. It was hypothesized
that a inhibitor wherein the 4-ethoxy-phenyl moiety is attached
to the core through a carbon atom would be more stable to oxida-
tion than through a nitrogen atom. This was considered a viable
strategy given that earlier optimization efforts demonstrated that
a broad variety of structural changes at the 8-aza-quinazolinone
core were tolerated.9 Unfortunately, it was found that while the
O-ethyl substituted phenol analogs, like compounds 1 and 4, were
not time-dependent inhibitors of CYP3A4, the phenol congeners 2
and 5 were time-dependent inhibitors of CYP3A4 (Fig. 2). This find-
ing suggested that the 4-ethoxy-phenyl functional group would
have to be replaced. Toward this end a cyano group was tested
as a potential replacement for the ethoxy moiety.
Our earlier efforts led to the discovery of a potent and selective
CXCR3 antagonist, AMG 487 (Fig. 1), which was evaluated in phase
I clinical trials.6 AMG 487 is a potent and selective inhibitor of
CXCR3. It inhibits binding of [125I]-IP-10 and [125I]-ITAC to CXCR3
with IC50 values of 8.0 and 8.2 nM, respectively, and inhibits
CXCR3-mediated migration in response to IP-10 (IC50 = 8 nM), ITAC
The synthesis of cyano-substituted analogs is outlined in
Scheme 1. In the first step of the synthesis, 4-iodoaniline 7 was
⇑
Corresponding author.
E-mail address: xiaoqic@amgen.com (X. Chen).
0960-894X/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmcl.2011.10.120

358
X. Chen et al. / Bioorg. Med. Chem. Lett. 22 (2012) 357–362
OEt
OEt
OH
O
N
O
N
O
N
N
O
N
O
N
O
N
N
N
N
N
N
N+
N
N
O-
F3CO
F3CO
F3CO
AMG 487
Binding assaya IC50 = 5 2 nM
Binding HS assayb IC50 = 49 22 nM
M1
M2
Binding assaya IC50 = 7 4 nM
Binding assaya IC50 = 816 nM
Binding HS assayb IC50 = 14 6 nM
Binding HS assayb IC50 = 4.1 µM
Figure 1. AMG 487 and metabolites M1 and M2. a Binding assay: [125I]-IP-10 in buffer; b binding HS (human serum) assay: [125I]-IP-10 in buffer in the presence of 100%
human serum.
OEt
OEt
OH
O
N
O
N
O
N
N
O
N
N
N
O
S
O
O
S
O
N
N
F3C
F
N
1
F3C
F
N
O
O
F3CO
AMG 487
2
OEt
OEt
OH
O
N
N
N
N
N
N
N
N
N
N
O
S
O
O
S
O
O
S
O
F3C
F
F3C
F
N
F3C
F
N
O
3
O
O
4
5
Figure 2. Ethoxide substituted CXCR3 analogs. AMG 487, compound 1, 3, 4 were not CYP3A4 time dependent inhibitors. Compound 2, 5 were CYP3A4 time dependent
inhibitors.
I
I
O
O
O
N
I
a
b
OH
NH2
+
N
H
N
H2N
Me
N
N
NH2
8
N
6
7
9
CN
CN
O
CN
O
N
O
N
c
d
e
N
N
N
Me
NH2
CN
Me
N
N
Me
N
N
Cl
10
11
12
O
N
CN
CN
O
N
O
N
h
f
g
N
N
Me
N
Me
Me
NH2
N
N
N
N
CF3
F
EtO2S
NH
EtO2S
O
15
13
14
Scheme 1. Synthesis of analog 15. Reagents: (a) EDC, HOBT, Et3N in CH2Cl2, 75%; (b) HOAc, triethyl orthopropionate, 60 °C, 78%; (c) Pd2(dba)3, dppf, Zn(CN)2, DMF, 115 °C,
96%; (d) NCS, HOAc, 40 °C, 99%; (e) NaN3, THF/H2O, then PMe3, 0 °C, 60% (two steps); (f) L-malic acid, resolution, 36%, 99% ee; (g) ethylvinyl sulfone, 65 °C; (h) 4-fluoro-3-
trifluoromethyl-phenyl acetic acid, EDC, HOBT, Et3N, 73% (two steps).
coupled with 2-aminonicotinic acid 6 using a standard peptide
coupling. The resulting amide 8 was subsequently cyclized with
triethyl orthopropionate to form the 8-aza-quinazolinone 9.10
Iodide 9 was converted to the cyano group by palladium-catalyzed
coupling with Zn(CN)2. This sequence of reactions was required
since 4-aminobenzonitrile was unreactive towards the formation

X. Chen et al. / Bioorg. Med. Chem. Lett. 22 (2012) 357–362
359
in wet THF followed by the addition of trimethylphosphine gave
primary amine 12. Compound 12 could be resolved by chiral chro-
matography or through selective recrystallization of the diastereo-
Table 1
Pharmacokinetic profile for analog 15a
Mouse
Rat
Beagle dog
Cynomolgus monkey
meric salt complex with L-malic acid to obtain enantiomerically
CLb (L/h/kg)
MRTb (h)
%Fc
0.35
0.70
17
2.4
0.53
47
1.0
1.2
69
0.74
1.7
13
pure 8-aza-quinazolinone 13. The amine of 13 was then alkylated
with ethylvinyl sulfone and followed by a standard amide coupling
with 4-fluoro-3-(trifluoromethyl)phenyl acetic acid to generate the
final product 15. Compound 15 was a highly potent CXCR3 antag-
onist. The binding IC50 of [125I]-IP-10 in buffer and [125I]-IP-10 in
the present of human serum were 10 and 18 nM, respectively.
Compound 15 effectively inhibited CXCR3-mediated in vitro cell
migration in response to ITAC (IC50 = 62 nM). The compound was
further evaluated in animals for its PK profile. It was found that
15 demonstrated moderate Cl in rat and beagle dog, with rates of
2.4 and 1.0 L/h/kg, respectively. However, the clearance rates were
a
Amorphous solid.
b
iv Dose 1 mg/kg in mouse and 0.5 mg/kg in rat, dog and monkey in 10%
N,N-dimethylacetamide, 10% ethanol, 30% propylene glycol, and 50% water.
c
p.o. Dose 5 mg/kg in mouse and 2 mg/kg in rat, beagle dog, and cynomolgus
monkey as a suspension in 1% Tween 80 in 1% methylcellulose.
of the pyridopyrimidin-4-one intermediate used in our original
synthesis. The benzylic position of 10 was chlorinated with NCS
to provide racemic chloride 11. Treatment of 11 with sodium azide
Table 2
Analogs evaluated in the chromosomal aberrations assay
R1
Core
N
R3
R2
O
Compd. Core
R1
R2
R3
[
125I]-IP-10 binding
ITAC migration IC50
(nM)
Chromosomal aberrations
assaya
Buffer IC50
(nM)
With HS IC50
(nM)
O
S
O
O
O
3-CF3,
4-F
N
N
N
N
N
15
CN
CN
CN
CN
CN
CN
CN
F
11
10
13
7
46
23
29
15
12
17
22
58
—
+
+
+
+
À
+
+
À
N
N
O
S
O
O
4-CF3,
3-F
16
47
—
N
N
O
S
O
3-CF3,
4-F
17
N
N
O
O
S
4-CF3,
3-F
O
O
18
37
39
—
N
N
O
O
S
3-CF3,
4-F
19
8
N
N
O
S
S
O
O
O
3-CF3,
4-F
N
N
20
21
2
N
O
O
S
O
4-OCF3
6
60
292
N
O
O
4-CF3,
3-F
N
22
47
N
N
Binding assay: [125I]-IP-10 in buffer; binding HS (human serum) assay: [125I]-IP-10 in buffer in the presence of 100% human serum; migration: ITAC mediated migration in the
presence of 100% human serum.
a
Chromosomal aberrations in cultured human peripheral blood lymphocytes at concentration of 7.81–1000
lg/mL (+S9 and ÀS9) at Covance Inc.

360
X. Chen et al. / Bioorg. Med. Chem. Lett. 22 (2012) 357–362
Table 3
Analogs which tested negative in the chromosomal aberrations assay
R1
O
N
N
O
N
R3
R4
N
R2
Compd.
R1
R2
R3
R4
[
125I]-IP-10 binding assay
ITAC migration IC50 (nM)
Buffer IC50 (nM)
With HS IC50 (nM)
S
23
24
Cl
Cl
CF3
F
F
6
22
102
107
O2
S
CF3
7
6
21
12
O2
SO2
SO2
25
26
Cl
Cl
CF3
F
F
45
55
CF3
7
13
S
22
27
F
F
CF3
F
F
42
47
50
58
254
292
O2
S
CF3
O2
SO2
28
29
F
F
CF3
F
F
7
7
17
22
72
90
SO2
CF3
Binding assay: [125I]-IP-10 in buffer; binding HS (human serum) assay: [125I]-IP-10 in buffer in the presence of 100% human serum; migration: ITAC mediated migration in the
presence of 100% human serum.
Table 4
Pharmacokinetic profile of analogs 25a and 28a in multiple species
Mouse
Rat
Beagle dog
Cynomolgus monkey
25
28
25
28
25
28
25
28
CLb (L/h/kg)
MRTb (h)
0.13
3.9
0.48
45
0.34
2.1
0.73
59
0.49
3.5
1.9
69
2.1
2.4
5.0
>100
1.5
1.1
1.4
>100
0.89
1.5
1.3
0.12
8.7
1.2
44
0.34
6.4
2.2
51
b
Vdss (L/kg)
%Fc
>100
a
b
c
Amorphous solid.
iv Dose 1 mg/kg in mouse and 0.5 mg/kg in rat, beagle dog and cynomolgus monkey in 10% N,N-dimethylacetamide, 10% ethanol, 30% propylene glycol, and 50% water.
p.o. Dose 5 mg/kg in mouse and 2 mg/kg in rat, cynomolgus monkey and beagle dog as a suspension in 1% Tween 80 in 1% methylcellulose.
low in mice and cynomolgus monkeys of 0.35 and 0.74 L/h/kg,
respectively (Table 1).
39 nM. Switching the position of the fluoro and trifluoromethyl
group in the acetamide of 15 did not affect the CXCR3 inhibitory
activity. The list of compounds which were tested in the chromo-
somal aberration assay is tabulated in Table 2. With the exception
of compound 19, the remaining compounds that feature the CN
moiety were positive in the chromosomal aberration assay. Evalu-
ation of the pharmacokinetic properties of 19 showed that the
compound had a low rate of clearance in mice, beagle dogs and
cynomolgus monkeys, the clearance was 0.49, 0.5, and 1.3 L/h/kg
after iv dosing of 1.0, 0.5, and 0.5 mg/kg, respectively. However,
the oral bioavailability of this molecule was rather poor. The oral
bioavailability was 17% in mouse and only 1.6% and 1% in beagle
dog and cynomolgus monkey following a p.o. dosing of 5, 2, and
2 mg/kg, respectively. It was possible that the poor oral bioavail-
ability of compound 19 was the result of low permeability. The
PAMPA permeability11 of 19 measured 0–0.1 Â 10À6 cm/s perme-
The cyano replacement of the ethoxy substituent in 3 afforded a
compound (15) that did not produce any metabolites with CYP3A4
time-dependent inhibitory (TDI) activity. However, while com-
pound 15 was negative in the Ames test for mutagenic potential,
it tested positive in the in vitro chromosomal aberration assay.
To this end, a series of related analogs, 16–22 were prepared and
submitted for the chromosomal aberration assay for a better
understanding of this issue (Table 2). With the exception of com-
pounds 19 and 22, the compounds featuring the nitrile moiety
were positive in the chromosomal aberration assay. It was found
that replacement of the ethyl sulfone group with a cyclic sulfone
to generate compounds 18 and 19 afforded CXCR3 antagonists
with increased potency. The IC50 of ITAC mediated migration assay
of 18 and 19 in the presence of 100% human serum was 37 and

X. Chen et al. / Bioorg. Med. Chem. Lett. 22 (2012) 357–362
361
Average Cells/mL
6.0E+05
Total Cells
5.0E+05
4.0E+05
3.0E+05
2.0E+05
1.0E+05
0.0E+00
PBS
10
1
10
3
1
Veh
-------------------
---------------------------------
Compound 25 (mg/kg)
AMG 487 (mg/kg)
Exposure (µM)*
Mouse WB IC50 (µM)
AMG 487
2.3
0.16
1.9
1.3
0.2
3.4
5.6
Compound 25
*1 hour post dose
Figure 3. Mouse Bleomycin efficacy model results of AMG 487 and compound 25 against lung inflammation.
ability between pH 5 and 7.4. It was speculated that the favorable
chromosomal aberration results might also be attributed to the
intrinsically low permeability of the compound.
0.48 L/kg in mouse to 1.9 L/kg in rats. This variance followed the
same rank order as the extent of plasma protein binding across
species. The unbound fractions were 0.7%, 6.1%, 1.5%, and 3.7% in
mice, rats, dogs, and monkeys, respectively. The half-life (T1/2) of
25 after intravenous dosing was approximately 4 h in mice and
rats, 1 h in dogs, and 9 h in monkeys.
Following oral gavage administration, 25 exhibited moderate to
high oral bioavailability (%F). Oral bioavailabilities of 25 ranged
from 44% to 69% in mice, rats, and cynomolgus monkeys. In beagle
dogs, the apparent bioavailability exceeded 100% due to nonlinear
pharmacokinetic behavior.
Compound 25 was further evaluated in a CXCR3 receptor
occupancy assay in whole blood. The CXCR3 occupancy assay
was performed via FACS analysis by using a fluorescently-tagged
anti-CXCR3 antibody. Addition of the CXCR3 ligand, ITAC, results
in the loss of fluorescent signal of antibody. The CXCR3-antagonists
blocks ITAC binding against receptor, but this series of compounds
does not block binding of the anti-CXCR3 antibody to the CXCR3
receptor. An ITAC concentration of 500 ng/mL was used in the as-
say. In this assay, compound 25 demonstrated IC50 values of 200
and 9.8 nM using mouse and human whole blood, respectively.
It has been shown that CXCR3 plays an important role in a mouse
model of lung injury induced by bleomycin administered by the in-
tra-tracheal route.12 Changes in bronchoalveolar lavage (BAL) fluid
attributed to bleomycin treatment include increased total cell count
followed by a sustained increase in lymphocyte count. In this effi-
cacy experiment, C57BL/6 mice were treated by a single intra-tra-
cheal instillation 1 mg/kg of bleomycin. The previous clinical
candidate, AMG 487, was used as a positive control in this experi-
ment. AMG 487 and compound 25 were dosed subcutaneously with
the use of an Alzetosmotic mini-pump onthe same day of bleomycin
challenge for 6 days.13 A BAL was performed on day six and the num-
ber of cells was counted. Plasma samples were collected at the end of
the experiment to determine drug level.
Replacement of the cyano group with a fluorine resulted in com-
pound 22, which tested negative in the chromosomal aberration as-
say. This SAR trend indicated that the cyano group could be the cause
for the positive results in the chromosomal aberration assay. In addi-
tion, compound 22 had a better PAMPA permeability of 0.8–1.4 Â 10
À6 cm/s at pH of 5–7.4 than compound 19. However, its potency as a
CXCR3 antagonist was diminished (Table 2). The potency was in
agreement with the previous SAR that showed the fluoride-substi-
tuted analogs had lower activity in the binding and migration assays
when compared to the ethoxy or cyano substituted phenyl analogs.
However, it was interesting to note that 22 showed relatively good
potency in the CXCR3 binding in the presence of human serum, with
an IC50 of 58 nM. Based on this evidence and previous SAR, a logical
choice was to further investigate the chloro-substituted analogs. A
number of chloro-substituted ethyl sulfone analogs were synthe-
sized and tested in the CXCR3 assay (Table 3). Compounds 23 and
24 displayed good potency in the binding and migration assays (Ta-
ble 3). Cyclic sulfone analogs 25 and 26 demonstrated increased po-
tency when compared to the ethyl sulfone analogs 23 and 24,
especially in the CXCR3-mediated in vitro cell migration assay med-
iated by ITAC. Compounds 25 and 26 were profiled in the CYP inhi-
bition assay. It was found that both 25 and 26 showed IC50 values
of greater than 10 lM against CYP 3A4 and 2D6. In addition, com-
pounds 25 and 26 tested negative for inducing chromosomal aberra-
tions, with and without metabolic activation, confirming the
hypothesis that the cyano-substitution was likely responsible for
the positive chromosomal aberration results.
Based on their potency in the CXCR3 in vitro assays compounds
25 and 28 were selected for further evaluation. The in vivo phar-
macokinetic properties of compounds 25 and 28 were profiled in
multiple species including, mice, rats, beagle dogs, and cynomolgus
monkeys and the results are summarized in Table 4. In general,
compound 25 demonstrated lower clearance and longer half lives
across the species tested with the exception of dogs. The plasma
clearance (CL) of 25 was low in mice, rats, and monkeys (3–15% he-
patic blood flow), but higher in dogs (82% hepatic blood flow). The
volume of distribution (Vdss) varied across species, ranging from
Compound 25 was effective in blocking leukocyte migration into
the lungs of mice following bleomycin challenge with an effective
dose of 1 mg/kg (Fig. 3). The level of blocking of cell penetration
was similar to the CXCR3 knockout animals. This dose results in
blood levels of 1.3
lM 1 h post dose, which is six-fold the mouse
whole blood receptor occupancy assay IC50
.

362
X. Chen et al. / Bioorg. Med. Chem. Lett. 22 (2012) 357–362
Kozlowski, J. A.; Anilkumar, G. N.; Rosenblum, S. B. Bioorg. Med. Chem. Lett.
In conclusion, through detailed compound optimization efforts,
2009, 19, 5205; (c) Bongartz, J. P.; Buntinx, M.; Coesemans, E.; Hermans, B.; Van
Lommen, G.; Van Wauwe, J. Bioorg. Med. Chem. Lett. 2008, 18, 5819; (d) Watson,
R. J.; Allen, D. R.; Birch, H. L.; Chapman, G. A.; Galvin, F. C.; Jopling, L. A.; Knight,
R. L.; Meier, D.; Oliver, K.; Meissner, J. W. G.; Owen, D. A.; Thomas, E. J.;
Tremayne, N.; Williams, S. C. Bioorg. Med. Chem. Lett. 2008, 18, 147; (e) Knight,
R. L.; Allen, D. R.; Birch, H. L.; Chapman, G. A.; Galvin, F. C.; Jopling, L. A.; Lock, C.
J.; Meissner, J. W. G.; Owen, D. A.; Raphy, G.; Watson, R. J.; Williams, S. C. Bioorg.
Med. Chem. Lett. 2008, 18, 629; (f) Watson, R. J.; Allen, D. R.; Birch, H. L.;
Chapman, G. A.; Hannah, D. R.; Knight, R. L.; Meissner, J. W. G.; Owen, D. A.;
Thomas, E. J. Bioorg. Med. Chem. Lett. 2007, 17, 6806; (g) Storelli, S.; Verzijl, D.;
Al-Badie, J.; Elders, N.; Bosch, L.; Timmerman, H.; Smit, M. J.; De Esch, I. J. P.;
Leurs, R. Archiv der Pharmazie (Weinheim, Germany) 2007, 340, 281; (h) Allen, D.
R.; Bolt, A.; Chapman, G. A.; Knight, R. L.; Meissner, J. W. G.; Owen, D. A.;
Watson, R. J. Bioorg. Med. Chem. Lett. 2007, 17, 697; (i) Cole, A. G.; Stroke, I. L.;
Brescia, M. R.; Simhadri, S.; Zhang, J. J.; Hussain, Z.; Snider, M.; Haskell, C.;
Ribeiro, S.; Appell, K. C.; Henderson, I.; Webb, M. L. Bioorg. Med. Chem. Lett.
2006, 16, 200; (j) Heise, C. E.; Pahuja, A.; Hudson, S. C.; Mistry, M. S.; Putnam, A.
L.; Gross, M. M.; Gottlieb, P. A.; Wade, W. S.; Kiankarimi, M.; Schwarz, D.;
Crowe, P.; Zlotnik, A.; Alleva, D. G. J.Pharm. Exp. Therap. 2005, 313, 1263; (k)
Ondeyka, J. G.; Herath, K. B.; Jayasuriya, H.; Polishook, J. D.; Bills, G. F.;
Dombrowski, A. W.; Mojena, M.; Koch, G.; DiSalvo, J.; DeMartino, J.; Guan, Z.;
Nanakorn, W.; Morenberg, C. M.; Balick, M. J.; Stevenson, D. W.; Slattery, M.;
Borris, R. P.; Singh, S. B. Mol. Divers. 2005, 9, 123; (l) Storelli, S.; Verzijl, D.; Al-
Badie, J.; Elders, N.; Bosch, L.; Timmerman, H.; Smit, M. J.; De Esch, I. J. P.; Leurs,
R. Arch. Pharm. 2007, 340, 281.
several CXCR3 antagonists with improved in vitro potency over
AMG 487 were discovered. These compounds lack the ethoxy
group responsible for the circulating metabolite M2, which causes
the CYP3A4 TDI in vivo with AMG 487. Furthermore, these com-
pounds avoid the formation of the pyridine N-oxide active metab-
olite, M1 also observed with AMG 487. Compound 25 showed good
oral bioavailability in multiple preclinical species and demon-
strated efficacy in a mouse model of bleomycin-induced leukocytes
trafficking into the lung. Moreover, 25 showed potent inhibitory
activity in a CXCR3 receptor occupancy assay using human and
mouse whole blood.
References and notes
1. (a) Mahad, D. J.; Howell, S. J. L.; Woodroofe, M. N. J. Neurol. Neurosurg. Psychiatry
2002, 72, 498; (b) Mahad, D. J.; Lawry, J.; Howell, S. J.; Woodroofe, M. N. Mult.
Scler. 2003, 9, 189; (c) Sorensen, T. L.; Tani, M.; Jensen, J.; Pierce, V.; Lucchinetti,
C.; Folcik, V. A.; Qin, S.; Rottman, J.; Sellebjerg, F.; Strieter, R. M.; Frederiksen, J.
L.; Ransohoff, R. M. J. Clin. Invest. 1999, 103, 807; (d) Sorensen, T. L.; Trebst, C.;
Kivisakk, P.; Klaege, K. L.; Majmudar, A.; Ravid, R.; Lassmann, H.; Olsen, D. B.;
Strieter, R. M.; Ransohoff, R. M.; Sellebjerg, F. J. Neuroimmunol. 2002, 127, 59.
2. (a) Uguccioni, M.; Gionchetti, P.; Robbiani, D. F.; Rizzello, F.; Peruzzo, S.;
Campieri, M.; Baggiolini, M. Am. J. Pathol. 1999, 155, 331; (b) Yuan, Y. H.; Hove,
T.; The, F. O.; Slors, J. F.; van Deventer, S. J.; Velde, A. A. Inflamm. Bowel Dis. 2001,
7, 281.
6. Johnson, M.; Li, A. R.; Liu, J.; Fu, Z.; Zhu, L.; Miao, S.; Wang, X.; Xu, Q.; Huang, A.;
Marcus, A.; Xu, F.; Ebsworth, K.; Sablan, E.; Danao, J.; Kumer, J.; Dairaghi, D.;
Lawrence, C.; Sullivan, T.; Tonn, G.; Schall, T.; Collins, T.; Medina, J. Bioorg. Med.
Chem. Lett. 2007, 17, 3339.
7. Tonn, G. R.; Wong, S. G.; Wong, S. C.; Johnson, M. G.; Ma, J.; Cho, R.; Floren, L. C.;
Kersey, K.; Berry, K.; Marcus, A. P.; Wang, X.; Van Lengerich, B.; Medina, J. C.;
Pearson, P. G.; Wong, B. K. Drug Metab. Dispos. 2009, 37, 502.
8. Liu, J.; Fu, Z.; Li, A. R.; Johnson, M.; Zhu, L.; Marcus, A.; Danao, J.; Sullivan, T.;
Tonn, G.; Collins, T.; Medina, J. Bioorg. Med. Chem. Lett. 2009, 19, 5114.
9. Du, X.; Gustin, D. J.; Chen, X.; Duquette, J.; McGee, L. R.; Wang, Z.; Ebsworth, K.;
Henne, K.; Lemon, B.; Ma, J.; Miao, S.; Sabalan, E.; Sullivan, T. J.; Tonn, G.;
Collins, T. L.; Medina, J. C. Bioorg. Med. Chem. Lett. 2009, 19, 5200.
10. Chan, J.; Gustin, D. J.; Divirgilio, E.; Guram, A.; Faul, M. M. Synthesis 2007, 23,
3678.
11. Balimane, P.; Han, Y. H.; Saeho; Chong, S. AAPS J. 2008, 8, E1.
12. Jiang, D.; Liang, J.; Hodge, J.; Lu, B.; Zhu, Z.; Yu, S.; Fan, J.; Gao, Y.; Yin, Z.; Homer,
R.; Gerard, C.; Noble, P. W. J. Clin. Invest. 2004, 114, 291–299.
3. (a) Patel, D. D.; Zachariah, J. P.; Whichard, L. P. Clin. Immunol. 2001, 98, 39; Qin,
S.; Rottman, J. B.; Myers, P.; Kassam, N.; Weinblatt, M.; Loetscher, M.; Koch, A.
E.; Moser, B.; Mackay, C. R. J . Clin. Invest. 1998, 101, 746.
4. (a) Agostini, C.; Calabrese, F.; Rea, F.; Facco, M.; Tosoni, A.; Loy, M.; Binotto, G.;
Valente, M.; Trentin, L.; Semenzato, G. Am. J. Pathol. 2001, 158, 1703; (b) Melter,
M.; Exeni, A.; Reinders, M. E.; Fang, J. C.; McMahon, G.; Ganz, P.; Hancock, W.
W.; Briscoe, D. M. Circulation 2001, 104, 2558; (c) Goddard, S.; Williams, A.;
Morland, C.; Qin, S.; Gladuem, R.; Hubscher, S. G.; Adams, D. H. Transplantation
2000, 72, 1957; (d) Hancock, W. W.; Wang, L.; Ye, Q.; Han, R.; Lee, I. Curr. Opin.
Immunol. 2003, 15, 479; (e) Segerer, S.; Cui, Y.; Eitner, F.; Goodpaster, T.;
Hudkins, K. L.; Mack, M.; Cartron, J. P.; Colin, Y.; Schlondorff, D.; Alpers, C. E.
Am. J. Kidney Dis. 2001, 37, 518.
5. (a) Crosignani, S.; Missotten, M.; Cleva, C.; Dondi, R.; Ratinaud, Y.; Humbert, Y.;
Mandal, A. B.; Bombrun, A.; Power, C.; Chollet, A.; Proudfoot, A. Bioorg. Med.
Chem. Lett. 2010, 20, 3614; (b) McGuinness, B. F.; Carroll, C. D.; Zawacki, L. G.;
Dong, G.; Yang, C.; Hobbs, D. W.; Jacob-Samuel, B.; Hall, J. W.; Jenh, C. H.;
13. Alzet osmotic mini-pump with
subcutaneously. The infusion rate was 1
visit http://www.alzet.com/downloads/TIM.pdf.
a
volume of 0.2 mL was implanted
lL/h. For more information, please