Discovery and SAR of cinnolines/quinolines as liver X receptor (LXR) agonists with binding selectivity for LXRβ

Article abstract of DOI:10.1016/j.bmc.2009.04.012

A series of cinnolines/quinolines was prepared and it was found that 4-phenyl-cinnoline/quinolines with either a 2′,3′ or 2′,5′-disubstituted benzyloxy moiety or the 1-Me-7-indole methoxy moiety on the meta position of the 4-phenyl ring showed good binding selectivity for LXRβ over LXRα. The LXRβ binding selective modulators displayed good activity for inducing ABCA1 gene expression in J774 macrophage cell line and poor efficacy in the LXRα Gal4 functional assay. 26, 37 and 41 were examined for their ability to induce SREBP-1c gene expression in Huh-7 liver cell line and they were weak partial agonists.

Full text of DOI:10.1016/j.bmc.2009.04.012

Bioorganic & Medicinal Chemistry 17 (2009) 3519–3527
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Discovery and SAR of cinnolines/quinolines as liver X receptor (LXR)
agonists with binding selectivity for LXRb
a
a
b
c
Baihua Hu a, , Raymound Unwalla , Michael Collini , Elaine Quinet , Irene Feingold ,
*
Annika Goos-Nilsson d, Anna Wihelmsson d, Ponnal Nambi b, Jay Wrobel a
a Chemical and Screening Science, Wyeth Research, 500 Arcola Road, Collegeville, PA 19426, USA
b Cardiovascular and Metabolic Disease, Wyeth Research, Collegeville, PA, USA
c Bio Transformation and Disposition, Wyeth Research, Collegeville, PA, USA
d Karo-Bio, Huddinge, Sweden
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 27 February 2009
Revised 8 April 2009
Accepted 9 April 2009
Available online 12 April 2009
A series of cinnolines/quinolines was prepared and it was found that 4-phenyl-cinnoline/quinolines with
either a 20,30 or 20,50-disubstituted benzyloxy moiety or the 1-Me-7-indole methoxy moiety on the meta
position of the 4-phenyl ring showed good binding selectivity for LXRb over LXR
selective modulators displayed good activity for inducing ABCA1 gene expression in J774 macrophage cell
line and poor efficacy in the LXR Gal4 functional assay. 26, 37 and 41 were examined for their ability to
a. The LXRb binding
a
induce SREBP-1c gene expression in Huh-7 liver cell line and they were weak partial agonists.
Keywords:
Ó 2009 Elsevier Ltd. All rights reserved.
Liver X receptor (LXR)
LXRb binding selective agonists
Cinnoline
Quinoline
1. Introduction
and fatty acid synthase (FAS) which limits the utility of these LXR
synthetic agonists. Several strategies1,2 have been proposed for
Liver X receptors (LXR
a
and LXRb) are members of the nuclear
the improvement of the therapeutic window of LXR agonists
including LXRb subtype selective agonists, partial agonists, and
gene or tissue specific agonists. The first hypothesis is based on
hormone receptor super family and are involved in the regulation
of cholesterol and lipid metabolism.1,2 They are ligand-activated
transcription factors and bind to DNA as obligate heterodimers with
retinoid X receptors (RXR). In macrophages, liver, and intestine,
activation of LXRs induce the expression of several genes involved
in lipid metabolism and reverse cholesterol transport including
ATP binding cassette transport A1 (ABCA1), ATP binding cassette
transport G1 (ABCG1) and apolipoprotein E (ApoE). The potential
to prevent or even reverse atherosclerotic process by increasing
the expression of these genes makes LXR an attractive drug target
for the treatment of atherosclerosis which is one of the leading
health concerns in the United States.3 Several LXR pan agonists (
Fig. 1), such as GW39654, TO901317,5 and WAY-254011,6 have
been shown to increase expression of several genes involved in lipid
metabolism and reverse cholesterol transport including ABCA1,
ABCG1 and ApoE. These compounds reduced or even reversed ath-
erosclerotic processes in mouse models of atherosclerosis. Cur-
rently available synthetic LXR pan agonists, however, also
activated triglyceride (TG) synthesis in the liver by the up regula-
tion of sterol regulatory element binding protein 1c (SREBP-1c)
the observation that LXR
in the liver and that activation of LXR
a
is the predominant isoform expressed
may be responsible for the
a
TG liability in vivo. Therefore, LXRb selective LXR modulators may
have less impact on TG synthesis, but may be effective in macro-
phage reverse cholesterol transport. Thus our new efforts were fo-
cused on the identification of LXRb selective modulators. A recent
study has shown that ligand activation of LXRb reversed atheroscle-
rosis and cellular cholesterol overload in mice lacking LXR
a and
ApoE.7 This observation provided strong in vivo support for LXRb
as a drug target for the treatment of atherosclerosis. Unfortunately,
there are only minor structural differences in the ligand binding do-
mains (LBD) of LXR
highly b-selective ligands. The two LXR isoforms
a
and LXRb that can be exploited to obtain
/b share a high
a
sequence identity (78%) and residue differences are located far
away from the ligand binding pocket.8 This high similarity in the
binding pocket of the two LXR isoforms constitutes a serious obsta-
cle to the development of highly b-selective ligands. Nevertheless, a
modest level of LXRb selectivity in a small molecule has been
achieved. N-Acylthiadiazoline 5 with preferential affinity for LXRb
in scintillation proximity assays (SPA) measuring total binding
* Corresponding author. Tel.: +1 484 865 7867; fax: +1 484 865 9399.
E-mail address: hub@wyeth.com (B. Hu).
(LXRb IC50 0.3 lM, LXRa IC50 9.8 l
M) has been reported.9 Func-
0968-0896/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2009.04.012

3520
B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
H
O
CO2H
O
O
N
N
S
F3C
F3C
O
Cl
HO
F3C
HO
CF3
2 (GW-3965)
3 (TO901317)
1
F
CO2H
CO2H
O
F
N
H
F
O
N
N
N
S
MeO
N
6
CF3
4 (WAY-254011)
Cl
OMe
CF3
5
Figure 1. Known LXR agonists.
tional selectivity was also confirmed using macrophages derived
from LXR-null mice: compound 5 showed significantly higher
expression of ABCA1 in LXRa-null macrophages than in LXRb-null
Following literature precedent for analogous transformations 2-
amino-3-chloro-benzophenones 7 were synthesized via the Sugas-
awa reaction11 between an aniline and a nitrile in the presence of
stoichiometric amounts of AlCl3 and BCl3. Conversion of 7 into the
corresponding cinnoline phenol derivatives 8 was readily achieved
in two steps by diazotization (NaNO2/acid) of the 2-aminobenz-
ophenones 7 followed by cyclization upon heating at 80 °C. Reflux-
ing the phenol 8 with phosphorus oxychloride or phosphorus
oxybromide afforded good yields of the corresponding cinnoline
halo derivatives 9. Reaction of 9 with phenylboronic acid under
standard Suzuki conditions provided 10. Reductive amination of
10 (Y = NH2) with benzyl aldehydes gave the desired 8-chloro-ben-
zyl-amine cinnolines 11. 8-Chloro-benzyl-ether cinnolines 12 were
prepared from 10 (Y = OH) under standard Mitsonobu conditions
or alkylations with benzyl bromides under basic conditions.
For 8-CF3-cinnolines because CF3 group does not survive the
Sugasawa reaction conditions (BCl3–AlCl3), an alternative synthesis
was developed as shown in Scheme 2. The Weinreb amide 1312
was prepared using standard conditions from commercially avail-
able 2-fluoro-3-trifluoromethylbenzoic acid. Treatment of 13 with
phenylethylmagnesium bromides gave fluorobenzophenones 14.
Conversion of 14 into aniline 15 was accomplished with ammo-
nium hydroxide at 140 °C in a steel pressure reactor. The aniline
macrophages. We previously identified quinoline-based agonists
with a 20,30,- or 20,50-dimethylphenyl acetic acid moiety (such as
6) or a naphthalene acetic acid moiety that showed good binding
affinity for LXRb and moderate to good binding selectivity for LXRb
over LXR
gain selectivity via ligand interaction with LXRb Ile277/LXR
a.
10 The premise for the design of these compounds was to
a
Val263.
However, compound 6 also exhibited cross-activity with peroxi-
some proliferator-activated nuclear receptors (PPAR). In an effort
to eliminate PPAR activity and maintain or improve LXRb selectivity
we prepared a series of substituted cinnolines/quinolines in which
the acetic acid of 6 was removed and a variety of substitutions on
the adjunct phenyl ring were examined.
2. Results and discussion
2.1. Synthetic chemistry
In an attempt to enlarge the chemical diversity of LXRb selective
ligands, we prepared a series of cinnoline derivatives as shown in
Scheme 1 (8-chloro-cinnolines) and Scheme 2 (8-CF3-cinnolines).
O
Cl
a
HO
R1
H2N
b, c
d
X
R1 CN
R1
R1
H2N
N N
Cl
N N Cl
9, X = Cl or Br
Cl
8
7, R1 = Ph or Bn
R3
e
H
N
R3
Y = NH2
R2
+
Y
O
f
R1
R2
N
N
11
R1
Cl
O
R3
N
N
Cl
R3
R2
Y = OH
g
R2
10, Y = OH or NH2
+
Br
R1
N
N
12
Cl
Scheme 1. Reagents and conditions: (a) BCl3/AlCl3, 30–60%; (b) NaNO2/H+; (c) 80 °C, 20–80% over all yield for step (b) and (c); (d) POBr3/DMF or POCl3, 90–100%;
(e) arylboronic acids, K3PO4, Pd(PPh3)4, dioxane, 30–85%; (f) benzyl amines, NaBH(OAc)3, DMF, 30–90%; (g) benzyl bromides/K2CO3 or benzyl alcohol, DIAD, PPh3; 30–90%.

B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
3521
O
F
O
F
O
F
O
OMe
Bn
Bn
NH2
N
a, b
d
OH
c
CF3
CF3
14
CF3
CF3
15
13
R1
R2
OH
Bn
OH
h
O
Bn
e
f, g
N
N
N
Bn
N
CF3
CF3
17
N
N
18
16
CF3
Scheme 2. Reagents and conditions: (a) SOCl2, 84% (b) NMeOMe; (c) PhCH2CH2MgCl, 81% for step (b) and (c); (d) NH3/DMF, 90%; (e) NaNO2/H+, 20–80%; (f) POBr3, DMF, 34%
for step (e) and (f); (g) K3PO4, Pd(PPh3)4, dioxane, 74%; (h) benzyl bromides, K2CO3, or benzyl alcohol, DIAD, PPh3, 30–90%.
15 was then converted to 8-CF3 cinnolines 18 in the same manner
as shown in Scheme 1. Quinoline analogs (39 to 42) were prepared
as previously described.6,13
cinnoline scaffold) were prepared14 and they showed similar LXRb
binding potency and selectivity as the quinoline-based compounds
4 and 6. However, these acetic acid substituted cinnolines also had
unwanted PPAR activity, activating all three subtypes of the PPAR.
It is speculated that the phenyl acetic acid moiety is responsible for
the PPAR activity, and we therefore focused our new efforts on the
synthesis of analogs without the acid moiety. The LXR binding
affinity of the newly synthesized compounds was evaluated in
radioligand binding assays as reported.6 As a reference, TO-
901317 (compound 3) was tested in our binding assays and was
found to be a potent LXR pan agonist (Table 1). As would be ex-
pected from the earlier quinoline series,10 non-substituted (19)
or mono substituted benzyl analogs (20 and 21) showed potent
2.2. LXR receptor binding assays
Results from the quinoline series10 showed that 20,30-dimethyl-
phenyl acetic acid and 20,50-dimethylphenyl acetic acid substituted
quinolines enhanced LXRb binding selectivity. The substituents on
the phenyl acetic acid moieties were proposed to interact with the
LXRbIle277/LXRaVal263 residue, which is the only amino acid se-
quence difference within the LBD. Initially, several cinnoline acetic
acids (a combination of the phenyl acetic acid moieties and the
Table 1
Relative binding affinities of compounds 19–42 for LXR receptor
a and b
L-CH2-Ar
R2
X
N
R1
Compound
X
R1
R2
Ar
L
hLXRb IC50 (nM)*
hLXRa
IC50 (nM)*
Ratio a/b
3
9
2
4
14
10
58
1.4
5.0
15
46
610
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
N
CH
CH
CH
CH
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
CF3
CF3
CF3
CF3
CF3
CF3
Cl
Bn
Bn
Bn
Bn
Bn
Bn
Bn
Bn
Bn
Ph
Ph
Bn
Bn
Bn
Bn
Bn
Bn
Bn
Bn
Ph
Bn
Bn
Bn
Bn
Ph
2-Cl–Ph
3-CF3–Ph
O
O
O
O
O
O
O
NH
NH
O
NH
O
O
O
O
O
46
14
10
24
12
85
44
40
62
65
19
57
38
63
43
42
14
24
24
10
34
20
39
38
180
92
62
837
147
1826
1191
1124
3.9
6.7
6.2
36
12
21
2-Cl–3-CF3–Ph
2-Cl–5-CF3–Ph
2-CF3–5-Cl–Ph
2-CF3–5-F–Ph
2-Cl–3-CF3–Ph
2-CF3–5-F–Ph
2-CF3–5-Cl–Ph
2-Cl–3-CF3–Ph
2-CF3–5-Cl–Ph
2-CF3–5-F–Ph
2-F–3-CF3–Ph
2-Cl–3-CF3–Ph
1-Me–2-indole
1-Me–7-indole
1-Me–7-indole
1-Me–7-indole
1-Me–7-indole
1-Me–7-indole
1-Me–7-indole
1-Me–2-indole
1-H–7-indole
27
28
>1000
332
179
>16
5.1
9.6
>17
31
>1000
1194
1336
2927
>1000
>1000
>1000
603
62
1415
668
1123
134
21
68
>23
>71
>41
25
6.2
41
33
29
3.5
O
NH
NH
NH
NH
O
Cl
Cl
CF3
CF3
CF3
CF3
NH
NH
*
Results are given as the mean of at least two independent experiments. The standard deviations for these assays were typically 30% of mean or less.

3522
B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
(IC50 < 50 nM) binding affinity for LXRb, but their subtype binding
selectivity against LXR was low (<10-fold). Better binding selec-
tivity was observed with disubstituted analogs, such as 2-Cl–3-
CF3 substituted compound 22 (LXR /b ratio of 36). The binding
a
a
selectivity dropped to 12-fold when moving the CF3 substituent
from position 3 to position 5 (compound 23). The selectivity im-
proved to 21-fold when switching the orientation of the two sub-
stituents from 2-Cl–5-CF3 (compound 23) to 2-CF3–5-Cl
(compound 24), however, the LXRb binding affinity decreased from
12 nM for compound 23 to 85 nM for compound 24. Compared to
24 the 2-CF3–5-F analog 25 showed similar binding affinity (LXRb
IC50 44 nM) and selectivity (27-fold) toward LXRa.
Modifications on the linker region, C3- and C8-position were
undertaken. As it was seen in the quinoline series6,10,13 that the
analogs with a NHCH2 linker (compound 26 vs 22; 27 vs 25)
showed a similar potency or selectivity profile. However, the
introduction of phenyl substituent on the 3-position of the cinn-
oline ring resulted in a big loss in term of binding selectivity
(compound 28 vs 24; 29 vs 26) although the LXRb binding affinity
was similar between the pairs. In our SAR studies on quinoline-
based compounds, we have shown that the 8-Cl moiety can be al-
tered to a CF3 moiety without compromising the LXR binding
affinity.13 Interestingly, all the 8-CF3 compounds with 2,3 or
2,5-disubstituted phenyls (compounds 30–33) and N-methyl-in-
doles (34 and 35) seem to have good binding selectivity for LXRb
Figure 2. Compound 35 docked into the LXRb/WAY-254011 pocket (ligand is
shown in magenta). Only key residues of the binding site are shown for simplicity.
Residue difference, that is, Ile277(b)/Val263(a) closest to the ligand is highlighted in
yellow and distance from Cd of Ile277 to 7-methyl group of indole is shown in
magenta. Hydrogen bonds to key residues are shown as dotted cyan line.
tions to ligand selectivity could come from differential interaction
of residues outside the immediate binding site (>5 Å) which are
different in the two isoforms. Such effects could originate from
shift of one or more conserved residues within the binding pocket
which in turn could propagate to residues differences outside the
binding site. We believe such shifts in second shell residues are
responsible for the selectivity differences seen in the case of the
3-phenyl substituted analogs versus 3-benzyl substituted analogs,
that is, compound 28 versus 24; and 29 versus 26. For example in
order to accommodate the larger 3-benzyl group within the C2
pocket, the Phe residues within the C2 pocket would have to adopt
alternate rotamer states which could affect residues differences
seen in the outer shell of two isoforms.
(a
/b > 17). 1-Me-7-indole 35 was the most selective compound in
this 8-CF3 cinnoline series which had good (71-fold) binding
selectivity over LXR . The compound also showed potent binding
a
affinity (LXRb IC50 14 nM). While the 8-Cl-3-benzyl indole 36 was
also potent (24 nM) and selective (42-fold) the 8-Cl-3-phenyl in-
dole analog 37 was potent (LXRb IC50 10 nM) but not selective
(6.2-fold) against LXRa which is consistent with results obtained
by other 3-phenyl cinnoline analogues (28 and 29). Several clo-
sely related quinoline-based 1-methyl-indoles (39–41) were pre-
pared and they had basically the same LXRb binding affinity and
selectivity as the corresponding cinnolines (34–37). Compared to
the 1-methyl indoles the 1-H indole 42 showed similar binding
affinity (LXRb IC50 of 38 nM) but reduced selectivity (a/b 3.5-
fold).
2.4. Functional assays
2.3. Molecular modeling
A few binding selective LXR agonists were tested in Gal4 func-
tional transactivation assays (Table 2, for assay conditions see Ref.
6). In these assays, all binding selective compounds (22, 26, 31, 33,
35, 37, 39, and 41) proved to be LXRb partial agonists, reaching a
maximum activation of 75% when compared to the literature stan-
dard TO901317. The binding selective compounds showed large
efficacy differences in the Gal4 transactivation assays between
In order to understand the modest LXRb selectivity (a/b 71-fold)
of the cinnoline compound 35, we docked this ligand into a previ-
ously solved in-house X-ray structure of WAY-254011.6 The best
scoring pose of 35 from the docking studies is shown in Figure 2.
A similar binding mode was also observed for compound 39 of
the quinoline series.
LXRb and LXRa, although their potency differences were only 2–
Ligand recognition within the binding site was achieved by a
hydrogen bond interaction between the N1 atom of the cinnoline
7-fold. Compared to the reference compound 3 and pan agonist 4
these binding selective compounds showed reduced potency with
ring and the N
e
atom of His435 residue, while the N-3 benzyl group
very weak partial agonism on LXRa (1–23% efficacy), suggesting
was completely surrounded by hydrophobic Phe residues (271,
340, and 349)6 in the C2 pocket. The benzyloxy linker was able
to extend the indole group further out towards the b sheet region
and orient the N-methyl group of the 7-indole towards the conser-
vative amino acid difference Ile277(b)/Val263(a) at a distance of
5.3 Å to the Cd atom of Ile277 residue. At this distance, the non-
potentially less lipogenic impact on the triglyceride synthesis. Fur-
thermore, when profiled in the J774 macrophages, all of the bind-
ing selective compounds in Table 2 showed good potency (0.7 lM
or less) and high efficacy (71% or greater) for stimulating an endog-
enous LXR target gene ABCA1. As expected, the compounds in this
new series (without the acetic acid moiety) had no cross activity
bonded energy contribution of this methyl group from any differ-
against PPARa, c, and d receptors (data not shown) as measured
ential interaction with Ile277(b)/Val263
small, but important for ligands selectivity. The lack of selectivity
observed for the 1-H-7-indole 42 ( /b 3.5-fold) analog of the quin-
oline series when compared to the 1-Me-7-indole analog 39 ( /b
(
a
) residues are probably
in transiently transfected cell lines. As stated previously, LXRb
selective compounds should have less impact on the triglyceride
synthesis when compared to LXR pan agonists. In this regard, cinn-
oline 26 and 37, and quinoline 41 were tested in SREBP-1c gene
expression in Huh-7 cells and they showed much reduced potency
a
a
41-fold) further supports our hypothesis that extending groups,
that is, methyl in this region of the pocket, the ligand was able to
(EC50 > 1.0
for 26, 37% for 37, and 34% for 41) relative to pan agonists 3
(EC50 0.067 M, 100%) and 4 (EC50 0.168 M, 103%).
lM for the three compounds) and lower efficacy (34%
make some differential interactions with Ile277(b)/Val263
(a) residue
and enhance selectivity. It is also possible that additional contribu-
l
l

B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
3523
Table 2
Gene expression activity and Gal4 transactivation activity for binding selective compounds
Compound
LXRb IC50 (nM)
a/b ratio
Transactivation LXRb EC50
(
l
M, %eff)a,b
Transactivation LXR
a
EC50
(l
M, %eff)a,b
Macrophage ABCA1 EC50
(
l
M, %eff)a,b
3
9
2
1.4
5.0
36
28
31
68
71
25
41
29
0.178 (100%)
0.09 (63%)
6.54 (54%)
3.63 (20%)
3.65 (61%)
8.60 (52%)
1.16 (67%)
2.78 (35%)
4.17 (75%)
10.18 (53%)
0.135 (100%)
0.24 (90%)
15.3 (6%)
0.034 (100%)
0.041 (115%)
0.18 (81%)
0.35 (95%)
0.067 (71%)
0.12 (91%)
0.068 (109%)
0.70 (129%)
0.076 (104%)
0.109 (82%)
46
22
26
31
33
35
37
39
41
24
40
38
43
14
24
34
39
11.1 (1%)
8.41 (9.5%)
18.1 (5.5%)
8.32 (23%)
6.00 (11%)
12.0 (15%)
13.5 (13%)
a
Results are given as the mean of two to three independent experiments. The standard deviations for these assays were typically 50% of mean or less. The percentage of
efficacy is relative to reference compound 3.
b
LXR transactivation assay used Huh7 cells transfected with human LXR LBD fused to Gal4 DBD; ABCA1 gene regulation by LXR ligands was measured J774 (murine) cells.
2.5. ADME profile
4.1.1. 1-(2-Amino-3-chlorophenyl)-2-phenylethanone (7a)
2-Chlorophenylaniline (2.92 g, 23 mmol) in 25 mL of 1,2-dichlo-
roethane was added dropwise to a solution of 25.3 mL (25.3 mmol)
of BCl3 in xylene at 0–5 °C. 5.38 g (46 mmol) of benzyl cyanide and
3.37 g (25.3 mmol) of AlCl3 were added to the suspension, and the
reaction mixture was stirred at 80 °C for 20 h and cooled to 0 °C.
2 N HCl was added to the mixture and the mixture was then re-
fluxed for 30 min at 80 °C and extracted with dichloromethane.
The organic phase was washed with 1 M NaOH, dried, and evapo-
rated to yield 1.5 g of 7a as a gray solid (27%). 1H NMR (CDCl3) d
7.80 (d, 1H, J = 8.2 Hz), 7.41 (d, 1H, J = 7.7 Hz), 7.40–7.20 (m, 5H),
6.85 (br s, 2H), 6.62 (t, 1H, J = 7.8 Hz), 4.27(s, 2H); MS m/z 246.
While the principle goal of this study was to probe the LXRb
selectivity, drug-like properties of analogs were also evaluated.
Using human and mouse liver microsomes the in vitro metabolic
stability was investigated and the majority of the compounds
tested showed poor metabolic stability (t1/2 < 10 min, <40% remain
at 30 min) in both species. Upon oral administration (10 mg/kg) in
mice 35 had no detectable plasma exposure which is consisted
with the poor metabolic stability (t1/2 < 5 min). Poor absorption
may also be a factor since the compound had poor aqueous solubil-
ity (2 lg/mL) and high c Log P (7.82) value.
4.1.2. 8-Chloro-3-phenylcinnolin-4-ol (8a)
3. Conclusion
A solution of sodium nitrite (0.60 g, 8.4 mmol) in water (1.5 mL)
was added dropwise to a solution of 7a (1.5 g, 6.1 mmol) in acetic
acid (20 mL) and sulfuric acid (3.0 mL). After being stirred for
20 min at 80 °C the solution was poured into iced water and the
pH was adjusted to ꢁ6 with 2 N sodium hydroxide. The aqueous
layer was extracted with ethyl acetate. The combined organics
were dried over MgSO4 and concentrated. The material was puri-
fied via column chromatography using 5–50% ethyl acetate in hex-
ane as the eluent to yield 0.20 g of 8a as a pale yellowish gum
(13%). 1H NMR (CDCl3) d 10.32 (s, 1H), 8.30 (d, 1H, J = 7.0 Hz),
8.14–8.11 (m, 2H), 7.75 (d, 1H, J = 7.7 Hz), 7.52–7.40 (m, 3H),
7.34 (t, 1H, J = 7.7 Hz); MS (ES) m/z 257.0.
In summary, a series of novel cinnolines/quinolines was found
to be potent LXRb binders. This work has led to >60-fold LXRb
binding selective modulators even though there is only one ami-
no acid difference in the ligand binding domain (LXRbIle277/LXR
a
Val263). It was found that cinnolines/quinolines with a 20,30 or
20,50-disubstituted phenyl or1-Me-7-indole moiety showed good
(>25-fold) binding selectivity for LXRb over LXR
binding selective modulators showed good potency (0.7
a
. Those LXRb
M or
l
less) and efficacy (71% or greater) for inducing ABCA1 gene
expression in macrophages and no PPAR agonist activity. Cinno-
lines 26/37 and quinoline 41 also showed poor efficacy in the
LXR
a Gal4 functional assay and they were weak partial agonists
for inducing SREBP-1c gene expression in Huh-7 liver cells.
4.1.3. 3-Benzyl-8-chlorocinnolin-4-ol (8b)
Prepared from 2-chlorophenylaniline and 3-phenylpropanenitri-
le according to the procedures for 7a and 8a as a white solid in 56%
yield for the two steps. 1H NMR (DMSO-d6) d 13.2 (s, 1H), 8.02 (d, 1H,
J = 8.1 Hz), 7.92 (d, 1H, J = 7.5 Hz), 7.38 (t, 1H, J = 7.7 Hz), 7.35–7.25
(m, 4H), 7.25–7.15 (m, 1H), 4.07 (s, 2H); MS (ES) m/z 271.0.
4. Experimental
4.1. General
Solvents and chemicals were purchased from VWR and Aldrich
Chemical Co. and were used without further purification. Anhy-
drous and deuterated solvents as well as fine chemicals were pur-
chased from Aldrich Chemical Co and used without further
treatment. High-resolution mass spectra were taken on a Waters
LC-TOFMS instrument and were measured to within 5 ppm of the
calculated values. 1H NMR spectra were taken on a Bruker
DPX300 (300 MHz) instrument and delta values (d) were measured
in ppm using tetramethylsilane as an internal standard
(d = 0 ppm). High-performance liquid chromatography (HPLC)
was performed with an Agilent 1100F series instrument with auto
4.1.4. 4-Bromo-8-chloro-3-phenylcinnoline (9a)
A solution of 8a (0.19 g, 0.74 mol) and POBr3 (1.0 g, 3.5 mmol)
in DMF (10 mL) was heated to 50 °C for 30 min. The reaction was
poured into ice-water, adjusted to pH to ꢁ10 by diluted ammo-
nium hydroxide and extracted with ethyl acetate. The combined
organics were concentrated to yield 9a (0.15 g, 64%) as a pale yel-
low solid. 1H NMR (CDCl3) d 8.22 (d, 1H, J = 8.6 Hz), 8.00 (d, 1H,
J = 7.4 Hz), 7.90–7.82 (m, 2H), 7.80 (t, 1H, J = 7.5 Hz), 7.62–7.50
(m, 3H); MS (ES) m/z 318.8; HPLC purity 100% at 10.2 min; HRMS
calcd for C14H9BrClN2: 318.9632; found (ESI, [M+H]+): 318.9630.
sampler and
a diode array detector (Xterra RP18, 3.5u,
4.1.5. 3-Benzyl-4-bromo-8-chlorocinnoline (9b)
150 ꢀ 4.6 mm column, 1.2 mL/min, 85/15–5/95 solvent A–solvent
B for 10 min, hold 4 min, solvent A: ammonium formate buffer
(pH 3.5), solvent B: ACN/MeOH 1:1). Appropriate safety practices
were observed during all laboratory functions.
Prepared from 8b according to the procedure for 9a as a a pale
yellow solid in 82% yield. 1H NMR (acetone-d6): d 8.20 (d, 1H,
J = 8.5 Hz), 8.12 (d, 1H, J = 7.4 Hz), 7.96 (t, 1H, J = 7.4 Hz), 7.41 (d,

3524
B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
2H, J = 7.5 Hz), 7.30 (t, 2H, J = 7.2 Hz), 7.25–7.20 (m, 1H), 4.85 (s,
2H); MS (ES) m/z 333.0; HRMS calcd for C15H11BrClN2: 332.9789;
found (ESI, [M+H]+): 332.9786.
tion in THF) and the reaction was warmed to room temperature.
After 2 h the reaction was poured into 2 N HCl and extracted with
ether. The organic layer was dried (MgSO4) and concentrated. The
product was purified by column chromatography (eluent 5%
EtOAc/hexane) to give 14 as a clear oil (4.8 g, 81%). 1H NMR
(DMSO-d6) d 8.14 (t, 1H, J = 8.2 Hz), 8.02 (t, 1H, J = 7.8 Hz), 7.53
(t, 1H, J = 7.8 Hz), 7.30–7.25 (m, 4H), 7.20–7.17 (m, 1H), 3.37 (t,
2H, J = 7.5 Hz), 2.94 (t, 2H, J = 7.5 Hz); MS (ES) m/z 297.0; HPLC pur-
ity 100% at 10.7 min.
4.1.6. 3-(8-Chloro-3-phenylcinnolin-4-yl)phenol (10a)
Compound 9a (0.16 g, 0.5 mmol) was taken into DME/EtOH
(10 mL/2 mL). Then 3-hydroxyphenylboronic acid (0.16 g,
1.0 mmol) was added followed by 2 M Na2CO3 (1.5 mL, 3.0 mmol)
and finally Pd(PPh3)4 (0.06 g, 0.05 mmol). The reaction was re-
fluxed for 2 h and concentrated. The resulting material was puri-
fied via column chromatography using 5–50% ethyl acetate in
hexane to elute out 0.14 g (84%) of 10a as a pale yellow solid. 1H
NMR (DMSO-d6) d 9.65 (s, 1H), 8.15 (d, 1H, J = 7.5 Hz), 7.82 (t,
1H, J = 8.6 Hz), 7.64 (d, 1H, J = 8.6 Hz), 7.53–7.48 (m, 2H), 7.40–
7.30 (m, 3H), 7.26 (t, 1H, J = 7.9 Hz), 6.85–6.83 (m, 1H), 6.76–6.68
(m, 2H); MS (ES) m/z 330.9; HRMS calcd for C20H14ClN2O:
333.0789; found (ESI, [M+H]+): 333.0805.
4.1.12. 1-[2-Amino-3-(trifluoromethyl)phenyl]-3-
phenylpropan-1-one (15)
A solution of 14 (4.8 g, 16.2 mmol) and ammonium hydroxide
(150 mL of 30% solution) in DME (50 mL) was heated to 140 °C in
a steel pressure reactor. After 3 h the reaction was cooled to 0 °C,
the steel pressure reactor was opened and the reaction was parti-
tioned between water and EtOAc. The organic layer was dried
(MgSO4) and concentrated to give 15 as a yellow oil (4.3 g, 90%).
4.1.7. [3-(8-Chloro-3-phenylcinnolin-4-yl)phenyl]amine (10b)
Prepared from 9a and 3-aminophenylboronic acid according to
the procedure for 10a as a a pale yellow solid in 55% yield. 1H NMR
(DMSO-d6) d 8.14 (d, 1H, J = 7.4 Hz), 7.81 (t, 1H, J = 8.6 Hz), 7.68 (d,
1H, J = 8.3 Hz), 7.58–7.54 (m, 2H), 7.41–7.35 (m, 3H), 7.11 (t, 1H,
J = 7.7 Hz), 6.65–6.60 (m, 1H), 6.50–6.40 (m, 2H), 5.24 (br s, 2H);
MS (ES) m/z 332.1; HPLC purity 96% at 9.3 min; HRMS calcd for
C20H15ClN3: 332.0949; found (ESI, [M+H]+): 332.0937.
1H NMR (DMSO-d6)
d 8.18 (d, 1H, J = 7.4 Hz), 7.66 (t, 1H,
J = 6.8 Hz), 7.29 (br s, 2H), 7.28–7.25 (m, 4H), 7.20–7.15 (m, 1H),
6.71 (t, 1H, J = 7.8 Hz), 3.37 (t, 2H, J = 7.3 Hz), 2.92 (t, J = 7.3 Hz,
2H); MS (ES) m/z 293.9; HPLC purity 100% at 11.0 min; HRMS calcd
for C16H14F3NO: 294.1100; found (ESI, [M+H]+), 294.1110.
4.1.13. 3-Benzyl-4-bromo-8-(trifluoromethyl)cinnoline (16)
To a solution of 15 (4.2 g, 13.8 mmol) in AcOH (70 mL) and
H2SO4 (10 mL) was added a solution of NaNO2(1.8 g in 10 mL
H2O). The reaction was then heated to 70 °C. After 1.5 h the reac-
tion was cooled, poured into water and extracted with EtOAc.
The organic layer was dried (MgSO4) and concentrated to give a
dark solid which was dissolved in DMF (30 mL). POBr3 (2.5 g,
8.7 mmol) in DMF (30 mL) was added and the mixture was heated
to 75 °C. After 1 h the reaction was cooled and poured into water.
The aqueous layer was extracted with EtOAc and the organics were
dried (MgSO4) and concentrated to give a solid. The solid was trit-
urated with MeOH and filtered to give 16 (1.7 g, 34%) as a light yel-
low solid. 1H NMR (DMSO-d6) d 8.47 (d, 1H, J = 8.7 Hz), 8.44 (d, 1H,
J = 7.1 Hz), 8.13 (t, 1H, J = 7.8 Hz), 7.40–7.30 (m, 4H), 4.79 (s, 2H);
MS (ES) m/z 366.7.
4.1.8. 3-(3-Benzyl-8-chlorocinnolin-4-yl)phenol (10c)
Prepared from 9b and 3-hydroxyphenylboronic acid according
to the procedure for 10a as a pale yellow solid in 47% yield. 1H
NMR (CDCl3) d 7.84(d, 1H, J = 7.3 Hz), 7.50 (t, 1H, J = 8.5 Hz),
7.45–7.35 (m, 2H), 7.30–7.20 (m, 2H), 7.20–7.00 (m, 4H), 6.71 (d,
1H, J = 7.6 Hz), 6.61 (s, 1H), 5.40 (br s, 1H), 4.48 (d, 1H,
J = 13.8 Hz), 4.42 (d, 1H, J = 13.8 Hz); MS (ES) m/z 347; HPLC purity
98.4% at 10.2 min; HRMS calcd for C21H16ClN2O: 347.0946; found
(ESI, [M+H]+): 347.0932.
4.1.9. [3-(3-Benzyl-8-chlorocinnolin-4-yl)phenyl]amine (10d)
Prepared from 9b and 3-aminophenylboronic acid according to
the procedure for 10a as a a pale yellow solid in 72% yield. 1H NMR
(acetone-d6): d 7.99(d, 1H, J = 7.3 Hz), 7.71 (t, 1H, J = 7.3 Hz), 7.56
(d, 1H, J = 8.5 Hz), 7.26 (t, 1H, J = 7.7 Hz), 7.20–7.10 (m, 5H),
6.89–6.86(m, 1H), 6.61 (s, 1H), 6.50 (d, 1H, J = 7.4 Hz), 4.46 (s,
2H); MS (ESI) m/z 346; HPLC purity 97.8% at 9.8 min.
4.1.14. 3-[3-Benzyl-8-(trifluoromethyl)cinnolin-4-yl]phenol
(17)
A solution of 16 (1.7 g, 4.6 mmol), 3-hydroxyphenylboronic acid
(0.84 g, 6.0 mmol), Pd(PPh3)4 (300 mg), and K3PO4 (3.0 g) in diox-
ane (50 mL) was heated to reflux. After 6 h the reaction was cooled
and poured into water and extracted with EtOAc. The organic layer
was concentrated and the product was purified by column chroma-
tography (eluent 10% EtOAc/hexane) to give 17 as a white solid
(1.3 g, 74%). 1H NMR (DMSO-d6) d 9.82 (s, 1H), 8.34 (d, 1H,
J = 7.2 Hz), 7.90 (t, 1H, J = 8.0 Hz), 7.78 (d, 1H, J = 8.6 Hz), 7.39 (t,
1H, J = 7.1 Hz), 7.25–7.10 (m, 3H), 7.10–6.95 (m, 3H), 6.78–6.76
(m, 2H), 4.40 (m, 2H); MS (ES) m/z 381.1; HPLC purity 94% at
10.6 min; HRMS calcd for C22H15F3N2O+Na+: 403.1029; found
(ESI, [M+Na]+ calcd): 403.1029.
4.1.10. 2-Fluoro-N-methoxy-N-methyl-3-(trifluoromethyl)-
benzamide (13)
A couple of drops of DMF was added to a suspension of 2-fluoro-
3-(trifluoromethyl)benzoic acid (5.0 g, 24.0 mmol), SOCl2 (10 mL)
and dichloromethane (50 mL). The reaction was refluxed for 4 h
and concentrated. The residue was dissolved in 50 mL of chloro-
form and cooled in an ice bath. N,O-Dimethylhydroxylamine hydro-
chloride (4.0 g, 41.2 mmol) and pyridine (7 mL) were added. The
reaction was then warmed to room temperature, stirred over night
and concentrated. The residue was dilute with ether, washed with
diluted HCl and sodium carbonate. The organic layer was dried over
MgSO4 and concentrated to give an oil which was used for the next
reaction without further purification (5.1 g, 84%). 1H NMR (DMSO-
d6) d 7.84–7.92 (m, 2H), 7.51 (t, 1H, J = 7.8 Hz), 3.66 (s, 3H), 3.16 (s,
3H); MS (ESI) m/z 252.1; HPLC purity 100% at 7.8 min; HRMS calcd
for C10H10F4NO2: 252.0642; found (ESI, [M+H]+): 252.0651.
4.1.15. 3-Benzyl-4-[3-(benzyloxy)phenyl]-8-chlorocinnoline
(19)
A mixture of 10c (0.05 g, 0.14 mmol), benzyl bromide (0.06 g,
0.35 mmol), and cesium carbonate (0.20 g, 0.61 mmol) in DMF
(6 mL) was stirred at room temperature for 1 h. The reaction was
quenched with water and extracted with ethyl acetate. The organic
residue was purified by semi-preparative HPLC (Column: Phenom-
4.1.11. 1-[2-Fluoro-3-(trifluoromethyl)phenyl]-3-phenylpropan-
1-one (14)
To a cooled (0 °C) solution of 13 (5.0 g, 20 mmol) in THF (50 mL)
was added phenethyl magnesium chloride (50 mL of 1.0 M solu-
enex C18 Luna 21.6 mm x 60 mm, 5 lM; solvent A: Water (0.1%
TFA buffer); solvent B: acetonitrile (0.1% TFA buffer); solvent gradi-
ent: time 0: 0% B; 10 min: 100% B; hold 100% B 5 min. Flow rate:
22.5 mL/min) to provide 19 (41 mg, 67%) as a pale yellow solid.

B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
3525
1H NMR (DMSO-d6) d 8.10 (d, 1H, J = 7.4 Hz), 7.73 (t, 1H, J = 8.6 Hz),
4.1.21. 3-Benzyl-8-chloro-4-(3-{[5-fluoro-2-
7.48 (t, 1H, J = 8.0 Hz), 7.45–7.30 (m, 6H), 7.22–7.10 (m, 4H), 6.98–
6.96 (m, 3H), 6.89 (d, 1H, J = 6.5 Hz), 5.10 (d, 1H, J = 12.1 Hz), 5.03
(d, 1H, J = 12.1 Hz), 4.38 (d, 1H, J = 16.2 Hz), 4.34 (d, 1H,
J = 16.2 Hz); MS (ES) m/z 436.8; HPLC purity 98.6% at 11.7 min;
HRMS calcd for C28H22ClN2O: 437.1415; found (ESI, [M+H]+):
437.1411.
(trifluoromethyl)benzyl]oxy}phenyl)cinnoline (25)
Prepared from 10c and 5-fluoro-2-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a gum in 38% yield. 1H
NMR (DMSO-d6) d 8.10 (d, 1H, J = 6.9 Hz), 7.90–7.80 (m, 2H), 7.74
(t, 1H, J = 7.4 Hz), 7.63 (d, 1H, J = 9.2 Hz), 7.52 (t, 1H, J = 7.3 Hz),
7.50–6.85 (m, 9H), 5.26 (d, 1H, J = 13.0 Hz), 5.22 (d, 1H,
J = 13.0 Hz), 4.41 (d, 1H, J = 14.4 Hz), 4.36 (d, 1H, J = 14.4 Hz); MS
(ES) m/z 523.0; HPLC purity 99.4% at 12.0 min; HRMS calcd for
C29H20ClF4N2O: 523.1195; found ([M+H]+): 523.1171.
4.1.16. 3-Benzyl-8-chloro-4-{3-[(2-chlorobenzyl)oxy]phenyl}-
cinnoline (20)
Prepared from 10c and 2-chlorobenzyl bromide according to
the procedure for 19 as a gum in 60% yield. 1H NMR (DMSO-d6) d
8.09 (d, 1H, J = 7.2 Hz), 7.74 (t, 1H, J = 7.9 Hz), 7.72–6.90 (m,
14H), 5.15 (d, 1H, J = 11.7 Hz), 5.12 (d, 1H, J = 11.7 Hz), 4.41 (d,
1H, J = 14.7 Hz), 4.36 (d, 1H, J = 14.7 Hz); MS (ES) m/z 470.8; HPLC
purity 99.8% at 12.1 min; HRMS calcd for C28H21Cl2N2O: 471.1025;
found (ESI, [M+H]+): 471.1016.
4.1.22. [3-(3-Benzyl-8-chlorocinnolin-4-yl)phenyl][2-chloro-3-
(trifluoromethyl)benzyl]amine (26)
Compound 10d (0.05 g, 0.14 mmol) and 2-chloro-3-trifluorom-
ethylbenzaldehyde (0.1 g, 0.48 mmol) were mixed in DMF (2 mL)
and then treated with NaBH(OAc)3 (0.1 g, 0.47 mmol) and acetic
acid (1 mL). After stirring at 50 °C for 1 h the mixture was
quenched with water and then extracted with ethyl acetate. The
organic residue was purified by silica gel chromatography using
5–50% EtOAc/hexanes as eluent to provide 26 (45 mg, 60%) as a
yellow foam. 1H NMR (CDCl3) d 7.82 (dd, 1H, J = 6.6, 1.7 Hz), 7.64
(d, 1H, J = 7.6 Hz), 7.59 (d, 1H, J = 7.8 Hz), 7.50–7.05 (m, 10H),
6.72 (dd, 1H, J = 8.2, 2.2 Hz), 6.55 (d, 1H, J = 6.6 Hz), 6.27 (br s,
1H), 4.50–4.30 (m, 4H); MS (ESI) m/z 538; HPLC purity 100% at
12.0 min; HRMS calcd for C29H21Cl2F2N3: 538.1059; found
([M+H]+): 538.1059.
4.1.17. 3-Benzyl-8-chloro-4-(3-{[3-(trifluoromethyl)benzyl]-
oxy}phenyl)cinnoline (21)
Prepared from 10c and 3-trifluoromethylbenzyl bromide
according to the procedure for 19 as a a gum in 54% yield. 1H
NMR (DMSO-d6) d 8.10 (d, 1H, J = 7.6 Hz), 7.82–7.70 (m, 4H), 7.64
(t, 1H, J = 7.6 Hz), 7.50 (t, 1H, J = 7.8 Hz), 7.39 (d, 1H, J = 8.5 Hz),
7.25–7.10 (m, 4H), 7.05–6.85 (m, 4H), 5.21 (d, 1H, J = 12.6 Hz),
5.18 (d, 1H, J = 12.6 Hz), 4.35 (s, 2H); MS (ES) m/z 504.8; HPLC pur-
ity 98.2% at 11.9 min; HRMS calcd for C29H21ClF3N2O: 505.1289;
found (ESI, [M+H]+): 505.1309.
4.1.23. [3-(3-Benzyl-8-chlorocinnolin-4-yl)phenyl][5-fluoro-2-
(trifluoromethyl)benzyl]amine (27)
Prepared from 10d and 5-fluoro-2-trifluoromethylbenzalde-
hyde according to the procedure for 26 as a gum in 31% yield. 1H
NMR (DMSO-d6) d 7.83 (dd, 1H, J = 6.9, 1.2 Hz), 7.66 (dd, 1H,
J = 8.8, 5.3 Hz), 7.55–7.00 (m, 11H), 6.70–6.67 (m, 1H), 6.55 (d,
1H, J = 7.5 Hz), 6.23–6.21 (m, 1H), 4.55–4.35 (m, 4H); MS (ES) m/
4.1.18. 3-Benzyl-8-chloro-4-(3-{[2-chloro-3-(trifluoromethyl)-
benzyl]oxy}phenyl)cinnoline (22)
Prepared from 10c and 2-chloro-3-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a gum in 37% yield.
1H NMR (DMSO-d6)
d 8.10 (d, 1H, J = 7.3 Hz), 7.92 (d, 1H,
z
522.1; HPLC purity 97.3% at 11.9 min; HRMS calcd for
J = 7.7 Hz), 7.88 (d, 1H, J = 7.8 Hz), 7.74 (t, 1H, J = 8.6 Hz), 7.62 (t,
1H, J = 7.9 Hz), 7.53 (t, 1H, J = 7.8 Hz), 7.41 (d, 1H, J = 8.6 Hz),
7.30–7.10 (m, 4H), 7.10–6.90 (m, 4H), 5.27 (d, 1H, J = 12.9 Hz),
5.20 (d, 1H, J = 12.9 Hz), 4.42 (d, 1H, J = 14.7 Hz), 4.36 (d, 1H,
J = 14.7 Hz); MS (ES) m/z 538.7; HPLC purity 99.6% at 12.2 min;
HRMS calcd for C29H20Cl2F3N2O: 539.0899; found (ESI, [M+H]+):
539.0898.
C29H21ClF4N3: 522.1355; found (ESI, [M+H]+): 522.1368.
4.1.24. 8-Chloro-4-(3-{[5-chloro-2-(trifluoromethyl)benzyl]oxy}-
phenyl)-3-phenylcinnoline (28)
Prepared from 10a and 5-chloro-2-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a yellow solid in 27%
yield. 1H NMR (CDCl3) d 7.94 (d, 1H, J = 6.1 Hz), 7.70–7.10 (m, 11
H), 7.05 (d, 1H, J = 8.3 Hz), 6.92 (d, 1H, J = 7.4 Hz), 6.81 (br s, 1H),
5.17–5.12 (m, 2 H); MS (ES) m/z 525.1; HPLC purity 100% at
12.0 min; HRMS calcd for C28H18Cl2F3N2O: 525.0743; found (ESI,
[M+H]+): 525.0754.
4.1.19. 3-Benzyl-8-chloro-4-(3-{[2-chloro-5-(trifluoromethyl)-
benzyl]oxy}phenyl)cinnoline (23)
Prepared from 10c and 2-chloro-5-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a gum in 66% yield. 1H
NMR (DMSO-d6) d 8.10 (d, 1H, J = 8.4 Hz), 7.96 (s, 1H), 7.79–7.77
(m, 2H), 7.73 (t, 1H, J = 8.6 Hz), 7.52 (t, 1H, J = 7.9 Hz), 7.40 (d,
1H, J = 8.4 Hz), 7.27 (dd, 1H, J = 7.8, 2.0 Hz), 7.20–7.10 (m, 3H),
7.10–6.90 (m, 4H), 5.25 (d, 1H, J = 12.7 Hz), 5.19 (d, 1H,
J = 12.7 Hz), 4.40 (d, 1H, J = 14.9 Hz), 4.35 (d, 1H, J = 14.9 Hz); MS
(ES) m/z 539.0; HPLC purity 98.4% at 12.2 min; HRMS calcd for
C29H20Cl2F3N2O: 539.0899; found (ESI, [M+H]+): 539.0886.
4.1.25. [3-(8-Chloro-3-phenylcinnolin-4-yl)phenyl][2-chloro-3-
(trifluoromethyl)benzyl]amine (29)
Prepared from 10b and 2-chloro-3-trifluoromethylbenzalde-
hyde according to the procedure for 26 as a pale yellow solid in
39% yield. 1H NMR (DMSO-d6) d 8.12 (d, 1H, J = 6.6 Hz), 7.70–7.30
(m, 9 H), 7.15 (t, 1H, J = 7.8 Hz), 6.68 (d, 1H, J = 9.7 Hz), 6.58 (t,
1H, J = 6.2 Hz), 6.50–6.40 (m, 2H), 4.37 (d, 2H, J = 6.1 Hz); MS
(ESI) m/z 524; MS (ESI) m/z 522; HPLC purity 100% at 11.8 min;
HRMS calcd for C28H19Cl2F3N3: 524.0903; found (ESI-FT/MS,
[M+H]+): 524.0911.
4.1.20. 3-Benzyl-8-chloro-4-(3-{[5-chloro-2-(trifluoromethyl)-
benzyl]oxy}phenyl)cinnoline (24)
Prepared from 10c and 5-chloro-2-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a pale yellow solid in
43% yield. 1H NMR (DMSO-d6) d 8.09 (d, 1H, J = 7.4 Hz), 7.90–7.80
(m, 2H), 7.74 (t, 1H, J = 8.5 Hz), 7.68 (dd, 1H, J = 8.5, 1.5 Hz), 7.52
(t, 1H, J = 8.2 Hz), 7.41 (d, 1H, J = 8.5 Hz), 7.40–7.10 (m, 4H),
7.05–6.90 (m, 4H), 5.26 (d, 1H, J = 12.9 Hz), 5.20 (d, 1H,
J = 12.9 Hz), 4.41 (d, 1H, J = 14.5 Hz), 4.36 (d, 1H, J = 14.5 Hz); MS
(ES) m/z 539.0; HPLC purity 97.6% at 12.3 min; HRMS calcd for
C29H20Cl2F3N2O: 539.0899; found (ESI, [M+H]+): 539.0866.
4.1.26. 3-Benzyl-4-(3-{[5-chloro-2-(trifluoromethyl)benzyl]oxy}-
phenyl)-8-(trifluoromethyl)cinnoline (30)
Prepared from 17 and 5-chloro-2-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a gum in 64% yield. 1H
NMR (DMSO-d6) d 8.35 (d, 1H, J = 7.2 Hz), 7.95–7.80 (m, 3H), 7.74
(d, 1H, J = 8.2 Hz), 7.68 (d, 1H, J = 8.4 Hz), 7.54 (t, 1H, J = 7.9 Hz),
7.25–6.95 (m, 8H), 5.26 (d, 1H, J = 12.9 Hz), 5.20 (d, 1H,
J = 12.9 Hz), 4.42 (d, 1H, J = 14.7 Hz), 4.37 (d, 1H, J = 14.7 Hz); MS

3526
B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
(ESI) m/z 573; HPLC purity 100% at 12.2 min; HRMS calcd for
4.1.32. N-[3-(3-Benzyl-8-chlorocinnolin-4-yl)phenyl]-N-[(1-
methyl-1H-indol-7-yl)methyl]amine (36)
C30H20ClF6N2O: 573.1163; found (ESI, [M+H]+): 573.1156.
Prepared from 10d and 1-methylindoline-7-carbaldehyde
according to the procedure for 26 as a pale yellow solid in 50%
yield. 1H NMR (DMSO-d6) d 8.07 (d, 1H, J = 7.4 Hz), 7.74 (t, 1H,
J = 8.6 Hz), 7.54 (d, 1H, J = 8.3 Hz), 7.47 (d, 1H, J = 8.0 Hz), 7.29
(t, 1H, J = 7.9 Hz), 7.25–6.90 (m, 9H), 6.62 (br s, 1H), 6.51 (d, 1H,
J = 6.6 Hz), 6.40 (d, 1H, J = 3.1 Hz), 6.34 (t, 1H, J = 5.0 Hz),
4.60–4.56 (m, 2H), 4.42 (d, 1H, J = 14.0 Hz), 4.39 (d, 1H,
J = 14.0 Hz), 3.98 (s, 3H); MS (ESI) m/z 489; HPLC purity 99.0%
at 11.8 min; HRMS calcd for C31H26ClN4: 489.1841; found
([M+H]+): 489.1860.
4.1.27. 3-Benzyl-4-(3-{[5-fluoro-2-(trifluoromethyl)benzyl]oxy}-
phenyl)-8-(trifluoromethyl)cinnoline (31)
Prepared from 17 and 5-fluoro-2-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a yellow oil in 19% yield.
1H NMR (DMSO-d6) d 8.35 (d, 1H, J = 7.2 Hz), 7.92–7.85 (m, 2 H),
7.74 (d, 1H, J = 8.4 Hz), 7.65 (dd, 1H, J = 9.8, 2.8 Hz), 7.55 (t, 1H,
J = 8.3 Hz), 7.45 (td, 1H, J = 8.3, 1.2 Hz), 7.30–6.95 (m, 8H), 5.26
(d, 1H, J = 12.9 Hz), 5.20 (d, 1H, J = 12.9 Hz), 4.42 (d, 1H,
J = 14.7 Hz), 4.37 (d, 1H, J = 14.7 Hz); MS (ES) m/z 557.2; HPLC pur-
ity 100% at 12.0 min; HRMS calcd for C30H20F7N2O: 557.1458;
found (ESI, [M+H]+): 557.1440.
4.1.33. 3-(3-Benzyl-8-chlorocinnolin-4-yl)phenyl][(1-methyl-
1H-indol-2-yl)methyl]amine (37)
4.1.28. 3-Benzyl-4-(3-{[2-fluoro-3-(trifluoromethyl)benzyl]oxy}-
phenyl)-8-(trifluoromethyl)cinnoline (32)
Prepared from 10d and 1-methylindoline-2-carbaldehyde
according to the procedure for 26 as a pale yellow solid in 35%
yield; 1H NMR (DMSO-d6) d 8.06 (d, 1H, J = 7.4 Hz), 7.65 (t, 1H,
J = 8.3 Hz), 7.46 (t, 1H, J = 6.4 Hz), 7.40 (d, 1H, J = 7.9 Hz), 7.30–
6.90 (m, 9H), 6.60–6.45 (m, 4 H), 4.45–4.35 (m, 4H), 3.71 (s, 3H);
MS (ES) m/z 489.1; HPLC purity 98.4% at 11.7 min; HRMS calcd
for C31H26ClN4: 489.1840; found (ESI, [M+H]+), 489.1839.
Prepared from 17 and 2-fluoro-3-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a yellow foam in 11%
yield. 1H NMR (DMSO-d6) d 8.35 (d, 1H, J = 7.2 Hz), 7.92–7.87 (m,
2H), 7.82 (t, 1H, J = 6.9 Hz), 7.75 (d, 1H, J = 8.2 Hz), 7.53 (t, 1H,
J = 8.3 Hz), 7.47 (t, 1H, J = 8.0 Hz), 7.28–6.93 (m, 8H), 5.25 (d, 1H,
J = 12.3 Hz), 5.18 (d, 1H, J = 12.3 Hz), 4.40 (d, 1H, J = 15.1 Hz), 4.37
(d, 1H, J = 15.1 Hz); MS (ES) m/z 557.2; HPLC purity 96.7% at
11.9 min; HRMS calcd for C30H20F7N2O: 557.1458; found (ESI,
[M+H]+): 557.1450.
4.1.34. [3-(8-Chloro-3-phenylcinnolin-4-yl)phenyl][(1-methyl-
1H-indol-7-yl)methyl]amine (38)
Prepared from 10b and 1-methylindoline-7-carbaldehyde
according to the procedure for 26 as a pale yellow solid in 58%
yield. 1H NMR (DMSO-d6) d 8.10 (d, 1H, J = 7.2 Hz), 7.76 (t, 1H,
J = 8.5 Hz), 7.67 (d, 1H, J = 8.6 Hz), 7.50–7.10 (m, 8H), 6.96 (d, 1H,
J = 6.5 Hz), 6.90 (t, 1H, J = 7.4 Hz), 6.76 (dd, 1H, J = 8.2, 1.5 Hz),
6.58 (s, 1H), 6.46 (d, 1H, J = 7.4 Hz), 6.35 (d, 1H, J = 3.1 Hz), 6.20
(t, 1H, J = 4.9 Hz), 4.48 (d, 1H, J = 4.9 Hz), 3.85 (s, 3H); MS (ES) m/
z 474.9; HPLC purity 100% at 11.5 min; HRMS calcd for C30H24ClN4:
475.1681; found ([M+H]+): 475.1689.
4.1.29. 3-Benzyl-4-(3-{[2-chloro-3-(trifluoromethyl)benzyl]oxy}-
phenyl)-8-(trifluoromethyl)cinnoline (33)
Prepared from 17 and 2-chloro-3-trifluoromethylbenzyl bro-
mide according to the procedure for 19 as a yellow solid in 37%
yield. 1H NMR (DMSO-d6) d 8.35 (d, 1H, J = 7.2 Hz), 7.93–7.87 (m,
3H), 7.74 (d, 1H, J = 8.0 Hz), 7.62 (t, 1H, J = 7.8 Hz), 7.54 (t, 1H,
J = 8.3 Hz), 7.29–6.99 (m, 8H), 5.27 (d, 1H, J = 12.8 Hz), 5.20 (d,
1H, J = 12.8 Hz), 4.42 (d, 1H, J = 14.6 Hz), 4.37 (d, 1H, J = 14.6 Hz);
MS (ES) m/z 573.1; HPLC purity 97.7% at 12.1 min; HRMS calcd
for C30H20ClF6N2O: 573.1163; found (ESI, [M+H]+): 573.1159.
4.1.35. {3-[3-Benzyl-8-(trifluoromethyl)quinolin-4-yl]phenyl}-
[(1-methyl-1H-indol-7-yl)methyl]amine (39)
Prepared from [3-[3-benzyl-8-(trifluoromethyl)quinolin-4-yl]-
phenyl]amine13 and 1-methylindoline-7-carbaldehyde according
to the procedure for 26 as a foam in 36% yield. 1H NMR (metha-
nol-d4) d 8.87 (s, 1H), 8.06 (d, 1H, J = 7.4 Hz), 7.84 (d, 1H,
J = 8.5 Hz), 7.56 (t, 1H, J = 7.9 Hz), 7.46 (d, 1H, J = 7.9 Hz), 7.32 (t,
1H, J = 7.9 Hz), 7.25–6.85 (m, 9H), 6.55–6.53 (m, 1H), 6.39 (d,
1H, J = 3.1 Hz), 4.57 (d, 1H, J = 6.1 Hz), 4.54 (d, 1H, J = 6.1 Hz),
4.06 (d, 2H, J = 4.0 Hz), 3.95 (s, 3H); HPLC purity 98.6%
12.1 min; HRMS calcd for C33H27F3N3: 522.2152; found (ESI,
[M+H]+), 522.2142.
4.1.30. 3-Benzyl-4-{3-[(1-methyl-1H-indol-2-yl)methoxy]-
phenyl}-8-(trifluoromethyl)cinnoline (34)
DIAD (0.1 g, 0.51 mmol) was added slowly to a mixture of 17
(0.11 g, 0.3 mmol), PPh3 (0.1 g, 0.38 mmol) and (1-methyl-1H-in-
dol-7-yl)-methanol (0.08 g, 0.49 mmol) in 10 mL of diethyl ether.
After being stirred for 1 h, the reaction was concentrated and puri-
fied by silica gel chromatography (ether/hexanes) to give 34 as yel-
low foam (17 mg, 11%). 1H NMR (DMSO-d6) d 8.35 (d, 1H,
J = 7.2 Hz), 7.87 (t, 1H, J = 8.5 Hz), 7.74 (d, 1H, J = 7.8 Hz), 7.54–
7.50 (m, 2H), 7.46 (d, 1H, J = 8.2 Hz), 7.28–7.20 (m, 1H), 7.20–
6.90 (m, 9H), 6.59 (s, 1H), 5.32 (d, 1H, J = 12.4 Hz), 5.23 (d, 1H,
J = 12.4 Hz), 4.41 (d, 1H, J = 15.0 Hz), 4.38 (d, 1H, J = 15.0 Hz), 3.32
(s, 3H); MS (ES) m/z 524.1; HPLC purity 98.3% at 11.8 min; HRMS
calcd for C32H24F3N3O + Na+: 546.1764; found (ESI, [M+Na]+):
546.1775.
4.1.36. 3-Benzyl-4-{3-[(1-methyl-1H-indol-7-yl)methoxy]-
phenyl}-8-(trifluoromethyl)quinoline (40)
A mixture of 3-(3-benzyl-8-trifluoromethyl-quinolin-4-yl)-phe-
nol (0.20 g, 0.5 mmol) and triphenylphosphine (polymer-bound,
ꢁ3.2 mmol/g, 1 g) in DCM (5 mL) was stirred at room temperature
for 30 min and then treated with 1-methyl-1H-indol-7-yl)metha-
nol (0.08 g, 0.5 mmol) and diisopropyl azodicarboxylate (0.2 g,
1 mmol) in 5 mL of DCM. After stirring for 2 h the solid was re-
moved and the liquid was washed with water and then extracted
with ethyl acetate. The organic residue was purified by silica gel
chromatography using 0–100% EtOAc/hexanes as eluent to provide
40 (160 mg, 61%) as a white solid. 1H NMR (DMSO-d6) d 9.03 (s,
1H), 8.16 (d, 1H, J = 6.7 Hz), 7.70–7.65 (m, 2H), 7.58–7.49 (m,
2H), 7.31–7.10 (m, 6H), 7.05–6.90 (m, 5H), 6.44 (d, 1H,
J = 3.0 Hz), 5.44 (d, 1H, J = 11.2 Hz), 5.34 (d, 1H, J = 11.2 Hz), 4.04
(d, 1H, J = 5.3 Hz), 4.00 (d, 1H, J = 5.3 Hz), 3.94 (s, 3H); MS (ESI)
m/z 523; HPLC purity 100% at 12.2 min; HRMS calcd for
C33H26F3N2O: 523.1992; found (ESI, [M+H]+), 523.1997.
4.1.31. 3-Benzyl-4-{3-[(1-methyl-1H-indol-7-yl)methoxy]-
phenyl}-8-(trifluoromethyl)cinnoline (35)
Prepared from 17 and (1-methyl-1H-indol-7-yl)methanol
according to the procedure for 34 as a yellow foam in 45% yield.
1H NMR (DMSO-d6)
d 8.35 (d, 1H, J = 7.0 Hz), 7.91 (t, 1H,
J = 8.5 Hz), 7.77 (d, 1H, J = 7.8 Hz), 7.57 (d, 1H, J = 7.9 Hz), 7.54 (d,
1H, J = 8.3 Hz), 7.30–7.28 (m, 2H), 7.25–7.10 (m, 5H), 7.10–6.95
(m, 4H), 6.45 (d, 1H, J = 3.2 Hz), 5.46 (d, 1H, J = 11.2 Hz), 5.37 (d,
1H, J = 11.2 Hz), 4.45 (d, 1H, J = 15.4 Hz), 4.40 (d, 1H, J = 15.4 Hz),
3.96 (s, 3H); MS (ES) m/z 524.1; HPLC purity 96.0% at 11.8 min;
HRMS calcd for C32H25F3N3O: 524.1940; found (ESI, [M+H]+),
524.1943.

B. Hu et al. / Bioorg. Med. Chem. 17 (2009) 3519–3527
3527
4.1.37. {3-[3-Benzyl-8-(trifluoromethyl)quinolin-4-yl]phenyl}-
[(1-methyl-1H-indol-2-yl)methyl]amine (41)
logical assay data. We also thank Drs. Ron Magolda, Magid Abou-
Gharbia, Steve Gardell, and George Vlasuk for their support of this
work.
Prepared from [3-[3-benzyl-8-(trifluoromethyl)quinolin-4-yl]-
phenyl]amine13 and 1-methylindoline-7-carbaldehyde according
to the procedure for 26 as a white foam in 29% yield. 1H NMR
(DMSO-d6): d 8.96 (s, 1H), 8.12 (d, 1H, J = 7.1 Hz), 7.75 (d, 1H,
J = 8.9 Hz), 7.57 (t, 1H, J = 8.2 Hz), 7.46 (d, 1H, J = 7.8 Hz), 7.40 (t,
1H, J = 8.2 Hz), 7.27 (t, 1H, J = 7.6 Hz), 7.25–6.85 (m, 7H), 6.60 (br
s, 1H), 6.48 (d, 1H, J = 7.5 Hz), 6.40–6.35 (m, 2H), 4.40 (d, 2H,
J = 7.5 Hz), 4.00 (d, 1H, J = 5.0 Hz), 3.96 (d, 1H, J = 5.0 Hz), 3.72 (s,
3H); MS (ESI) m/z 522; HPLC purity 100% at 12.1 min; HRMS calcd
for C33H27F3N3: 522.2152; found (ESI, [M+H]+), 522.2151.
References and notes
1. Bennett, D. J.; Carswell, E. L.; Cooke, A. J.; Edwards, A. S.; Nimz, O. Curr. Med.
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B.; Parks, D. J.; Wilson, J. G.; Tippin, T. K.; Binz, J. G.; Plunket, K. D.; Morgan, D.
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4.1.38. {3-[3-Benzyl-8-(trifluoromethyl)quinolin-4-yl]phenyl}-
(1H-indol-7-ylmethyl)amine (42)
Prepared from [3-[3-benzyl-8-(trifluoromethyl)quinolin-4-yl]-
phenyl]amine13 and 1H-indole-7-carbaldehyde according to the
procedure for 26 as a foam in 82% yield. 1H NMR (DMSO-d6): d
11.1 (s, 1H), 8.92 (s, 1H), 8.12 (d, 1H, J = 7.1 Hz), 7.70 (d, 1H,
J = 8.7 Hz), 7.60 (t, 1H, J = 7.6 Hz), 7.43 (d, 1H, J = 7.9 Hz), 7.33 (t,
1H, J = 2.6 Hz), 7.30–6.90 (m, 17H), 6.80 (d, 1H, J = 8.2 Hz), 6.55–
6.40 (m, 3H), 4.50 (d, 2H, J = 6.8 Hz), 3.92 (s, 2H);MS (ES) m/z
508.2; HPLC purity 94.6% at 11.9 min; HRMS calcd for
C32H25F3N3: 508.1994; found (ESI, [M+H]+), 508.1992.
7. (a) Bradley, M. N.; Hong, C.; Chen, M.; Joseph, S. B.; Wilpitz, D. C.; Wang, X.;
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aꢂ/ꢂ mice and LXRbꢂ/ꢂ mice the
role of LXR and LXRb has been extensively studied, for a review on the
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4.2. Docking calculations
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Trybulski, E.; Chadwick, C. C.; Chippari, S.; Kenney, T.; Eckert, A.; Borges-
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13. Hu, B.; Jetter, J.; Kaufman, D.; Singhaus, R.; Bernotas, R.; Unwalla, R.; Quinet, E.;
Savio, D.; Halpern, A.; Basso, M.; Keith, J.; Clerin, V.; Chen, L.; Liu, Q.; Feingold,
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15. Glide, version 5.0, Schrodinger, LLC, New York, NY, 2008.
16. Friesner, R. A.; Banks, J. L.; Murphy, R. B.; Halgren, T. A.; Klicic, J. J.; Mainz, D. T.;
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Docking studies were carried out using Schrodingers Glide pro-
gram.15 Protein preparation was done on the in-house X-ray struc-
ture of hLXRb/WAY-254011 using the Protein Preparation Wizard,
a comprehensive protein preparation tool which adds hydrogens,
adjusts protonation states for ionizable residues, modifies tauto-
meric forms for histidine residues, and repositions hydrogens
(e.g., side chain hydroxyl hydrogens). This was followed by re-
strained minimization to allow hydrogens to be freely minimized
while allowing for sufficient heavy atom movement (0.3 A) to alle-
viate potential steric clashes. The final refined structure was then
visually examined for correct formal charges, bond order and pro-
tonation states. The receptor grid generation was done with the
scaling factors for van der Waals radii of non-polar atoms (those
with an absolute partial charge less than 0.25) set to 0.9. Ligand
was built using the Maestro interface and prepared for docking
using the LigPrep utility. Flexible docking of the ligand was per-
formed using the standard precision16,17 (SP) followed by post-
minimization of 5 best poses eliminate poses with close intraligand
distances and high strain energies.
Acknowledgments
We thank the Wyeth Discovery Analytic Chemistry Department
for the analytical data, and Anita Halpern and Dawn Savio for bio-