Synthesis and biological assay of 4-aryl-6-chloro-quinoline derivatives as novel non-nucleoside anti-HBV agents

Article abstract of DOI:10.1016/j.bmc.2011.01.006

A series of 4-aryl-6-chloro-quinoline derivatives were synthesized and evaluated for their anti-hepatitis B virus (HBV) activities, namely the abilities to inhibit the secretion of HBV surface antigen (HBsAg), HBV e antigen (HBeAg), and replication of HBV

Full text of DOI:10.1016/j.bmc.2011.01.006

Bioorganic & Medicinal Chemistry 19 (2011) 1400–1408
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry
journal homepage: www.elsevier.com/locate/bmc
Synthesis and biological assay of 4-aryl-6-chloro-quinoline derivatives
as novel non-nucleoside anti-HBV agents
Rui-Hua Guo a,b, Quan Zhang a, Yun-Bao Ma a, Xiao-Yan Huang a, Jie Luo a, Li-Jun Wang a,b, Chang-An Geng a,b
,
Xue-Mei Zhang a, Jun Zhou a, Zhi-Yong Jiang a, Ji-Jun Chen a,
⇑
a State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, PR China
b Graduate School of Chinese Academy of Sciences, Beijing 100039, PR China
a r t i c l e i n f o
a b s t r a c t
Article history:
A series of 4-aryl-6-chloro-quinoline derivatives were synthesized and evaluated for their anti-hepatitis B
virus (HBV) activities, namely the abilities to inhibit the secretion of HBV surface antigen (HBsAg), HBV e
antigen (HBeAg), and replication of HBV DNA in HepG 2.2.15 cells. Most of the compounds exhibited
moderate inhibitory activity against the secretion of HBsAg and HBeAg. Nine compounds (3, 5, 6, 7, 10,
14, 17, 20, 24) showed significant inhibition against HBV DNA replication with IC50 values in the range
Received 2 December 2010
Revised 4 January 2011
Accepted 5 January 2011
Available online 11 January 2011
of 4.4–9.8 lM, which were comparative to that of positive control tenofovir. Of them, compounds 10,
17, and 20 had low cytotoxicities, resulting in high SI values, >551.2, >143.7, and >284.5, respectively.
Keywords:
Hepatitis B virus
4-Aryl-6-chloro-quinoline
Derivatives
Crown Copyright Ó 2011 Published by Elsevier Ltd. All rights reserved.
Synthesis
1. Introduction
of HBeAg, HBsAg, and HBV DNA replication in vitro. The anti-
HBV mechanism of non-nucleosides is not confined to the HBV
Persistent infection with hepatitis B virus (HBV) remains a seri-
ous global health problem, leading to 1.2 million deaths per year
according to the world health organization.1 HBV infection can re-
sult in acute, fulminant, or chronic disease, liver cirrhosis, and the
development of hepatocelluar carcinomas.2 Current treatments for
DNA polymerase, which made them more potent to be developed
as anti-HBV agents.6,7 So far, non-nucleosides have also been re-
ported to inhibit HBV infection.7–18 Nevertheless, the search for
compounds with novel anti-HBV target and mechanism is still a
fascinating topic.
chronic HBV infection include the usage of
a
-interferon (interferon
Previously, we first reported that 4-aryl-6-chloroquinoline-2-
one analogues (Fig. 1) exhibited in vitro anti-HBV activity and
revealed their preliminary structure–activity relationship (SAR).19
Compound 1 showed moderate activity against the secretion of
HBV surface antigen (HBsAg) and HBV e antigen (HBeAg). In view
of its novel structural template, with compound 1 as starting mate-
rial, a series of 4-aryl-6-chloroquinoline analogues were designed
and synthesized (Fig. 1) via chemical modification at position 2
and C-3 hydroxyethyl moiety, and evaluated for their anti-HBV
activities in vitro in order to further study the structure–activity
relationships (SARs).
alpha-2a and PEGylated interferon alpha-2a) and nucleoside drug
(i.e., lamivudine, adefovir, entecavir, telbivudine, and tenofovir).
The mechanism of action of nucleoside analogues is suggested to
be through the interaction of their triphosphate derivatives,
formed after cellular metabolic transformation, with HBV DNA
polymerase or reverse transcriptase as substrates and/or inhibi-
tors.3 However, the use of
a-interferon can lead to low response
rate in the patient, while treatment with nucleoside analogues
results in development of drug-resistant virus after long-term
treatment.4,5 Nowadays, the development of new anti-HBV agents
is focused on discovering diverse compounds with either novel
structures or a new mechanism of action. Non-nucleosides with
various skeleton types exhibit inhibitory activity on the secretion
2. Chemistry
Treatment of compound 1 with phenylphosphonic dichloride
gave compound 2.20 Reaction of compound 1 with methanesulfo-
nyl chloride in the presence of triethylamine in CH2Cl2 afforded
derivative 3. Acylation of compound 1 yielded compound 4, which
was treated with phenylphosphonic dichloride to produce 2-Cl
Abbreviations: HBV, hepatitis B virus; HBsAg, hepatitis surface antigen; HBeAg,
hepatitis e antigen; SARs, structure–activity relationships; SI, selectivity index;
CC50, 50% cytotoxic concentration; IC50, 50% inhibitory concentration.
⇑
Corresponding author. Tel./fax: +86 871 5223265.
E-mail address: chenjj@mail.kib.ac.cn (J.-J. Chen).
derivative 5. Reaction of compound
5 with MeOH afforded
0968-0896/$ - see front matter Crown Copyright Ó 2011 Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmc.2011.01.006

R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
1401
H
H
N
N
O
N
R1
Cl
O
Cl
OH
Cl
R2
Cl
R2
R1
Cl
4-aryl-6-chloro-quinolin-2-one
4-aryl-6-chloro-quinoline
1
Figure 1. Structures of 4-aryl-6-chloro-quinoline-2-one, compound 1, and 4-aryl-6-chloro-quinoline.
2-OMe derivative 6. Deacylation of compound 5 without influence
3. Results and discussion
of 2-Cl was succeeded by refluxing with NH4OAc in MeOH/H2O
(4:1) to give compound 7, which was converted to methanesulf-
onylate 8. Subsequently, compound 8 underwent substitution
reaction with NaN3 to produce derivatives 9 and 10 as show in
Scheme 1.
As shown in Scheme 2, compound 1 was protected as tert-butyl-
diphenylsilyl (TBDPS) ether (11), followed by treatment with 2,6-
difluorobenzyl bromide/2,6-dichorobenzyl bromide in the
presence of K2CO3 in acetone to afford derivatives 12/13.21 Depro-
tection of TBDPS with TBAF (tetra-butylammoniumfluoride) gave
compounds 14/15.22 TBDPS ether (11) was converted to com-
pounds 17–20 through triflate formation, nucleophilic substitution
reaction with various amines. Compounds 21–24 were obtained by
deprotection of TBDPS group with TBAF in THF.
The potential anti-HBV activity and cytotoxicity of the synthe-
sized 4-aryl-6-chloro-quinoline analogues (1–3, 5–10, and 12–24)
were tested in HepG 2.2.15 cells, and tenofovir was used as a ref-
erence antiviral drug. The results were summarized in Table 1.
The anti-HBV activity of each compound was expressed as the con-
centration of compound that achieved 50% inhibition (IC50) of
HBsAg, HBeAg, and HBV DNA replication. The cytotoxicity of each
compound was expressed as the concentration of compound
required to kill 50% (CC50) of the HepG 2.2.15 cells. The selectivity
index (SI), an important pharmaceutical parameter that estimates
possible future clinical development, was determined as the ratio
of CC50 value to IC50 value. The bioactivity of each compound
was evaluated by the combination of its IC50 values and SI.
N
Cl
Cl
N
OMs
Cl
N
OCH3
OH
Cl
Cl
Cl
OMs
Cl
Cl
2
3
6
b
a
e
H
H
N
N
Cl
Cl
N
O
O
d
c
Cl
OAc
Cl
OAc
Cl
OH
Cl
Cl
5
4
1
N
Cl
f
Cl
N3
N
Cl
N
Cl
Cl
Cl
g
h
Cl
OMs
Cl
OH
9
+
Cl
N
N3
Cl
7
8
Cl
N3
10
Scheme 1. Reagents and conditions: (a) phenylphosphonic dichloride, 100 °C, 91%; (b) MsCl, TEA, DCM, rt, 8%; (c) Ac2O, pyridine, rt, 88%; (d) phenylphosphonic dichloride,
100 °C, 81%; (e) K2CO3, MeOH/H2O (4:1), refluxed, 69%; (f) NH4OAc, MeOH/H2O (4:1), refluxed, 84%; (g) MsCl, TEA, DCM, rt, 77%; (h) NaN3, DMF, 80 °C, 52% (9), 47% (10).

1402
R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
H
N
R1
N
O
R1
O
N
O
c
b
Cl
OH
Cl
R
Cl
OTBDPS
Cl
Cl
Cl
F
F
F
1
R=OH
1
1
12
R =
14
R =
a
F
11
R=OTBDPS
Cl
Cl
13 R1
=
15 R1
=
d
Cl
Cl
R2
N
R2
Cl
N
OTf
N
f
e
Cl
OH
Cl
OTBDPS
Cl
OTBDPS
Cl
Cl
16
R2
22 R2
=
=
=
N
21
R2
18 R2
=
=
=
=
N
17
O
N
N
O
N
N
R2
NH
R2
23
19
NH
N
N
N
N
24 R2 =
20 R2
HN
N
HN
N
Scheme 2. Reagents and conditions: (a) TBDPSCl, DMF, DIEPA, rt, 86%; (b) for 12: 2,6-difluorobenzyl bromide K2CO3, acetone, rt, 54%; for 13: 2,6-dichorobenzyl bromide,
K2CO3, acetone, rt, 49%; (c) TBAF, THF, rt, 90–91%; (d) Tf2O, DIEPA, pyridine, 86%; (e) DIEA, CH3CN, refluxed, 56–89%; (f) TBAF, THF, rt, 50–81%.
Compound 1 showed moderate inhibitory potency to the secre-
tion of HBsAg (IC50 = 70.2 M), HBeAg (IC50 = 340.5 M), and repli-
cation of HBV DNA (IC50 = 72.1 M), which led to relatively low SI
their anti-HBV activities and cytotoxicities, the results were shown
in Table 1. For 2-O-substituted derivatives 12–16, compounds 14
and 15 showed good efficacy against HBV DNA replication
l
l
l
values (SIHBsAg = 5.5, SIHBeAg = 1.1, SIHBV DNA = 5.4). When quinolin-
2-one compound 1 was converted to 2-Cl quinoline derivative 7,
the inhibitory activity against secretion of HBeAg and HBV DNA
replication were increased by 30- and 7.4-fold, respectively, but
inhibition to the secretion of HBsAg was increased slightly
(IC50 = 4.8, 17.7
the secretion of HBsAg (IC50 = 43.5, 18.2
peared toxic (CC50 = 108.9, 38.5 M, respectively), resulting in low
l
M, respectively) and moderate inhibition against
l
M, respectively), but ap-
l
SI values (SIHBV DNA = 22.7, 2.2, respectively; SIHBsAg = 2.5, 2.1,
respectively). Decreased cytotoxicities were observed with the
protection of hydroxyl groups of compounds 14 and 15 by TBDPS
(compounds 12 and 13), but the conversion resulted in the loss
of anti-HBV activity. 2-N-substituted subseries of compounds
17–24 were also synthesized to detect their anti-HBV activities.
For derivatives 21–24 with free hydroxyl groups at C-3 hydroxy-
ethyl moiety, compound 24 showed potent activity against HBV
(IC50 = 45.3
l
M vs IC50 = 70.2
lM). However, compound 7 was
toxic (CC50 = 42.5
lM), which led to low SI values. For compounds
2, 5, 8, 9 with different patterns of modification on C-3 hydroxy-
ethyl moiety, compounds 2, 5, 9 exhibited high activities against
HBV DNA replication and had low cytotoxicities with IC50 values
of 19.0 lM (SI >73.8), 6.1 lM (SI = 19.1), 16.6 lM (SI >151.4),
respectively, and were almost inactive against the secretion of
HBsAg and HBeAg. The methanesulfonylate 8 almost lost anti-HBV
activity. Compounds 3, 6, 10 had different substitutions on C-2 as
shown in Table 1, these compounds generally exhibited good po-
DNA replication with a IC50 value of 8.3
tory activities against the secretion of HBsAg (IC50 = 37.7
HBeAg (IC50 = 111.4 M). However, its high cytotoxicity
(CC50 = 82.4 M) led to low SI values (SIHBsAg = 2.2, SIHBeAg <1.0,
l
M and moderate inhibi-
l
M) and
l
l
tency against HBV DNA replication (IC50 = 6.8
lM, 6.1
lM, 4.5
lM,
SIHBV DNA = 10.0). Conversion of compound 24 to the corresponding
respectively). The results indicated that at position C-2 could accom-
modate some substitutions for their suppressant potency against
HBV comparing to 2-Cl derivative 7. Furthermore, compound 3
showed the highest activity against the secretion of HBsAg
TBDPS substituted derivative 20 induced 2-fold improvement on
inhibiting HBV DNA replication (IC50 = 4.4 lM vs IC50 = 8.3 lM)
and reduced cytotoxicity resulting in high SI value (SI >284.5),
whereas compound 20 lost suppressant property against the secre-
tion of HBsAg and HBeAg. Compound 21 showed weak potency
(IC50 = 16.5
l
M). It is worth noting that the most active compound
M),
10 was more potent and had low cytotoxicity (CC50 >2480.4
l
against HBV DNA replication (IC50 = 151.2
of TBDPS to hydroxyethyl moiety (compound 17), its anti-HBV
activity was enhanced by 22.6-fold (IC50 = 6.7 M vs IC50 = 151.2
M). Moreover, decreased activities against the secretion of HBsAg
and HBeAg were also observed.
lM). When introduction
resulting in high SI value of >551.2. These results indicated that
C-2 might be a good target for further lead optimization.
To further explore the influence of C-2 of quinoline on anti-HBV
activity, compounds 12–24 were synthesized and evaluated for
l
l

R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
1403
Table 1
Anti-HBV activity, cytotoxicity, and selectivity index of analogues (1–3, 5–10, 12–24)
H
N
R1
Cl
N
O
Cl
R2
Cl
OH
Cl
1
2, 3, 5-10, 12-24
a
Compd
R1
R2
CC50 (lM)
HBsAgb
M)
HBeAgc
M)
HBV DNA
IC50 (lM)
d
IC50
70.2
(l
SIe
IC50
340.5
(l
SI
SI
1
2
3
5
6
7
8
9
10
—
Cl
OMs
Cl
OCH3
Cl
Cl
Cl
N3
—
Cl
OMs
OAc
OH
OH
OMs
N3
387.5
>1401.6
804.1
116.4
141.2
5.5
—
1.1
—
72.1
19.0
6.8
6.1
6.9
5.4
>1401.6
16.5
>1401.6
367.3
>73.8
118.2
19.1
20.5
4.3
—
>151.4
>551.2
48.6
<1
2.1
<1
<1
—
2.2
<1
<1
3.8
>1.4
—
146.8
66.3
45.3
70.9
>2708.9
11.3
42.5
9.8
881.7
>2513.2
>2480.4
1020.9
>2513.2
>2480.4
646.6
>881.7
16.6
4.5
>2513.2
>2480.4
N3
—
—
F
O
O
12
OTBDPS
>1865.1
>1865.1
—
>1865.1
—
>1865.1
—
F
Cl
13
14
15
OTBDPS
>1026.0
108.9
38.5
>1026.0
43.5
—
>1026.0
1634.0
12.2
—
>1026.0
—
Cl
F
F
O
O
OH
2.5
2.1
<1
3.2
4.8
22.7
2.2
Cl
OH
18.2
17.7
Cl
16
17
OTf
OTBDPS
OTBDPS
>1562.5
>968.8
454.5
3.4
—
767.0
2.0
—
>1562.5
6.7
—
>968.8
>968.8
>143.7
N
18
19
OTBDPS
OTBDPS
>1203.1
<18.8
>1203.1
18.8
—
>1203.1
>1173.7
—
>1203.1
42.8
—
O
N
N
<1
<1
<4.43
NH
N N
HN N
20
OTBDPS
>1251.9
>1251.9
—
>1251.9
—
4.4
>284.5
21
22
23
OH
OH
OH
155.0
>1592.0
<5.0
37.5
323.4
>5.0
4.1
>4.9
<1
50.0
3.1
—
151.2
>1592.0
>5.0
1.0
—
N
>1592.0
>5.0
O
N
N
<1
—
NH
(continued on next page)

1404
R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
Table 1 (continued)
a
Compd
R1
R2
CC50
(l
M)
HBsAgb
M)
HBeAgc
M)
HBV DNA
M)
d
IC50
(l
SIe
IC50
(l
SI
IC50
(
l
SI
N N
HN N
24
OH
—
82.4
37.7
2.2
111.4
<1
8.3
10.0
Tenofovirf
—
>1740
1450.1
>1.2
1160.2
>1.5
0.54
>3222
a
CC50: 50% cytotoxic concentration.
HBsAg: HBV surface antigen.
HBeAg: HBV e antigen.
b
c
d
e
f
IC50: 50% inhibitory concentration.
SI (selectivity index) = CC50/IC50
.
Tenofovir: an antiviral agent used as positive control.
warm up to room temperature and stirred at room temperature
for 2 h. Then water (10.2 mL) was added over 10 min, and the reac-
tion mixture was stirred at room temperature for 24 h. The aque-
ous layer was extracted with ethyl acetate (100 mL) and the
organic layer was washed with water (80 mL) and brine
(3 Â 50 mL) and dried with anhydrous Na2SO4. Removal of the sol-
vents gave a residue which was purified by silica gel column chro-
matography (Si CC) with CHCl3/CH3OH (98:2) to obtain compound
1 (1.08 g, yield 86%) as white amorphous powder; 1H NMR (DMSO-
d6, 400 MHz) d 12.16 (1H, br s), 7.68 (1H, dd, J = 1.6, 5.2 Hz), 7.59–
7.49 (3H, m), 7.41–7.36 (2H, m), 6.56 (1H, s), 4.61 (1H, br s), 3.43
(2H, t, J = 7.2 Hz), 2.56–2.48 (1H, m), 2.31–2.29 (1H, m); 13C NMR
(DMSO-d6, 100 MHz) d 161.6, 144.5, 136.4, 134.1, 131.9, 131.2,
130.7, 130.5, 129.8, 129.7, 127.9, 125.9, 124.3, 120.4, 117.4, 58.8,
32.3; ESIMS: m/z 334 [M+H]+, HRESIMS: calcd for C17H14NO2Cl2
[M+H]+ 334.0401, found 334.0409.
4. Conclusions
A series of 4-aryl-6-chloro-quinoline derivatives mainly modi-
fied on C-2 and C-3 hydroxyethyl moiety were synthesized and as-
sayed for their anti-HBV activities and cytotoxicities in vitro. Most
compounds exhibited moderate inhibitory activity against the
secretion of HBsAg and HBeAg. Nine compounds (3, 5, 6, 7, 10,
14, 17, 20, 24) showed significant inhibition against HBV DNA rep-
lication with IC50 values in the range of 4.4–9.8 lM, which were
comparative to that of positive control tenofovir. Of them, com-
pounds 10, 17, and 20 had low cytotoxicities, resulting in high SI
values, >551.2, >143.7, and >284.5, respectively. Based on the
above results, the following conclusion could be made: (a) for C-
2 substituted quinoline derivatives, the anti-HBV activity largely
depends on the size and character of the substituents, and this po-
sition can accommodate some substituents without decreasing the
anti-HBV activity. (b) TBDPS substitution is an important feature in
the conferring relatively low cytotoxicity. (c) The role of TBDPS at
hydroxyethyl moiety for anti-HBV activity is ambiguous.
5.1.2. 2,6-Dichloro-3-(2-chloroethyl)-4-(2-chlorophenyl)
quinoline (2)
To solid compound 1 (50 mg, 0.15 mmol) in a flask was added
phenylphosphonic dichloride (2 mL). The mixture was slowly
warmed to 100 °C with stirring and kept for 2 h. The resulting mix-
ture was carefully basified with ammonium hydroxide, extracted
with EtOAc, washed with brine, dried with anhydrous Na2SO4. Re-
moval of the solvents gave a residue which was purified by Si CC
with petroleum ether/acetone (100:1) to afford compound 2
(50 mg, yield 91%) as white amorphous powder; 1H NMR (CDCl3,
500 MHz) d 8.00 (1H, d, J = 9.0 Hz), 7.66–7.62 (2H, m), 7.56–7.48
(2H, m), 7.25 (1H, dd, J = 7.5, 2.0 Hz), 7.12 (1H, d, J = 2.0 Hz),
3.67–3.63 (2H, m), 3.26–3.20 (1H, m), 3.07–3.01 (1H, m); 13C
NMR (CDCl3, 125 MHz) d 151.8, 147.4, 145.0, 133.9, 133.5, 133.0,
131.3, 130.9, 130.8, 130.3, 130.2, 129.0, 127.4, 127.3, 124.6, 41.2,
34.5; ESIMS: m/z 370 [M+H]+, HRESIMS: calcd for C17H12NCl4
[M+H]+ 369.9723, found 369.9733.
For 2-O-substituted analogues, etherification of hydroxyl group
at C-3 of 4-aryl-6-chloro-quinoline decreased anti-HBV activity.
For 2-N-substituted analogues, TBDPS substitution increased activ-
ity against HBV DNA replication, but caused the loss of suppressant
property on the secretion of HBsAg and HBeAg. The preliminary
SAR study provides valuable information for our on-going anti-
HBV studies on 4-aryl-6-chloro-quinoline compounds.
5. Experimental
5.1. Chemistry
MS spectra were run on a VG Auto Spec-3000 spectrometer (VG,
Manchester, England); NMR spectra were recorded on Bruker AM
400 (1H/13C, 400 MHz/100 MHz) or DRX-500 (1H/13C, 500 MHz/
125 MHz) spectrometer (Bruker, Bremerhaven, Germany) and
chemical shifts were given in d with TMS as internal reference; sil-
ica gel column chromatography (CC): silica gel (200–300 mesh);
Qingdao Makall Group Co., Ltd; Qingdao; China). All reactions were
monitored using thin-layer chromatography (TLC) on silica gel
plates.
5.1.3. 2-[6-Chloro-4-(2-chlorophenyl)-2-(methylsulfonyloxy)
quinolin-3-yl]ethylmethanesulfonate (3)
Methanesulfonyl chloride (372 mg, 3.26 mmol) was added
dropwise to a solution of compound 1 (300 mg, 0.90 mmol) and
Et3N (109 mg, 1.08 mmol) in CH2Cl2 (10 mL) at 0 °C. The reaction
was warmed to room temperature and stirred 4 h. The reaction
was then quenched with 5% HCl and extracted with EtOAc. The
combined organic layer was washed with brine, dried with anhy-
drous Na2SO4, and concentrated in vacuo to give the residue which
was purified by Si CC with petroleum ether/acetone (20:1) give
compound 3 (36 mg, yield 8%) as yellow amorphous power; 1H
NMR (CDCl3, 400 MHz) d 7.95 (1H, d, J = 8.9 Hz), 7.65 (2H, m),
7.52 (2H, m), 7.28 (1H, m), 6.86 (1H, d, J = 1.7 Hz), 4.34 (2H, m),
3.78 (3H, s), 3.13 (1H, m), 2.97 (1H, m), 2.92 (3H, m); 13C NMR
5.1.1. 6-Chloro-4-(2-chlorophenyl)-3-(2-hydroxyethyl)
quinolin-2(1H)-one (1)
A 100 mL, 2-neck flask was charged with 2-amino-2’,5-dic-
hlorobenzo-phenone (1.0 g, 3.76 mmol) and THF (20 mL). The
resulting solution was cooled to 0 °C and LiHMDS (28.2 mL, 1 M
in THF) was added over 15 min. The internal temperature was con-
trolled 0 °C for 10 min, then
c-valerolactone (1.7 g, 16.90 mmol)
was added over 10 min. The reaction solution was allowed to

R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
1405
(CDCl3, 100 MHz) d 155.2, 149.7, 143.1, 133.3, 133.2, 133.0, 131.4,
131.2, 130.9, 130.3, 129.9, 127.5, 127.4, 124.8, 121.1, 67.2, 41.9,
37.2, 28.0; FABMS: m/z 490 [M+H]+, HRESIMS: calcd for
and concentrated in vacuo to obtain the residue which was puri-
fied by Si CC with petroleum ether/acetone (5:1) to produce com-
pound 7 (41 mg, yield 84%) as white amorphous power; 1H NMR
(CDCl3, 400 MHz) d 7.95 (1H, d, J = 9.0 Hz), 7.61– 7.57 (2H, m),
7.50–7.42 (2H, m), 7.24 (1H, dd, J = 7.2, 1.9 Hz), 7.09 (1H, d,
J = 2.2 Hz), 3.85–3.73 (2H, m), 3.08–3.01 (1H, m), 2.90–2.83 (1H,
m); 13C NMR (CDCl3, 100 MHz) d 152.3, 147.2, 144.6, 134.3,
133.3, 133.1, 131.0, 131.0, 130.5, 130.2, 130.0, 129.5, 127.4,
127.3, 124.5, 60.9, 34.6; EIMS: m/z (%) 351 ([M]+, 24), 286 (65%),
250 (100%), 214 (60%), HREIMS: calcd for C17H12NOCl3 [M]+
350.9984, found 350.9981.
C
19H18NO6S2Cl2 [M+H]+ 489.9953, found 489.9951.
5.1.4. 2-[6-Chloro-4-(2-chlorophenyl)-2-oxo-1,2-dihydroquin-
olin-3-yl]ethylacetate (4)
To a solution of compound 1 (100 mg, 0.30 mmol), Ac2O (37 mg,
0.36 mmol) in anhydrous pyridine (5 mL), was stirred until the
starting material was not observed by TLC. The reaction mixture
was diluted with 50 mL of EtOAc and washed three times with
50 mL of 5% HCl and saturated NaHCO3 (3 Â 30 mL). The organic
layer was dried with anhydrous Na2SO4 and concentrated in vacuo
to give the residue which was purified by Si CC with CHCl3/MeOH,
(98:2) to afford the product 4 (99 mg, yield 88%) as white amor-
phous power; 1H NMR (CDCl3, 500 MHz) d 13.13 (1H, br s), 7.59
(1H, dd, J = 9.5, 2.0 Hz), 7.46 (4H, m), 7.25 (1H, m), 6.86 (1H, d,
J = 1.8 Hz), 4.30 (2H, t, J = 6.8 Hz), 2.95 (1H, m), 2.67 (1H, m), 1.97
(3H, s); 13C NMR (CDCl3, 125 MHz) d 170.8, 164.0, 147.1, 136.0,
134.2, 133.0, 130.7, 130.4, 130.3, 130.1, 129.1, 128.1, 127.2,
125.5, 121.1, 117.6, 62.3, 28.1, 21.1; FABMS: m/z 376 [M+H]+, HRE-
SIMS: calcd for C19H16NO3Cl2 [M+H]+ 376.0507, found 376.0497.
5.1.8. 2-[2,6-Dichloro-4-(2-chlorophenyl)quinolin-3-yl]ethyl
methanesulfonate (8)
A solution of compound 7 (50 mg, 0.14 mmol) and trimethyla-
mine (17 mg, 0.17 mmol) in 3 mL of dichloromethane was cooled
to 0 °C. A solution of methanesulfonyl chloride (32 mg, 0.28 mmol)
in 1 mL of dichloromethane was added dropwise. The ice was re-
moved and the mixture was stirred at room temperature for 3 h.
The mixture was extracted three times with 50 mL of EtOAc. The
combined organic layer was washed with brine, dried with anhy-
drous Na2SO4, and concentrated in vacuo to give the residue which
was purified by Si CC with petroleum ether/acetone (6:1) to yield
derivative 8 (46 mg, 77%) as white amorphous power; 1H NMR
(CDCl3, 400 MHz) d 7.99 (1H, d, J = 9.0 Hz), 7.64 (2H, m), 7.50
(2H, m), 7.27 (1H, dd, J = 7.2, 1.6 Hz), 7.12 (1H, d, J = 2.0 Hz),
4.38–4.34 (2H, m), 3.26–3.19 (1H, m), 3.08–3.01 (1H, m), 2.88
(3H, s); 13C NMR (CDCl3, 100 MHz) d 151.5, 147.9, 145.0, 133.65,
133.56, 132.8, 131.4, 131.0, 130.8, 130.23, 130.16, 127.5, 127.2,
127.1, 124.6, 66.8, 37.2, 31.1; EIMS: m/z (%) 429 ([M]+, 7), 298
(52), 262 (100), 214 (41), HREIMS: calcd for C18H14NO3SCl3 [M]+
428.9760, found 428.9754.
5.1.5. 2-(2,6-Dichloro-4-(2-chlorophenyl)quinolin-3-yl)ethyl
acetate (5)
To solid compound 4 (20 mg, 0.05 mmol) was added phenyl-
phosphonic dichloride (2 mL). The mixture was slowly warmed
to 100 °C with stirring and kept for 2 h. The resulting mixture
was carefully basified with ammonium hydroxide, extracted with
EtOAc, washed with brine, dried with anhydrous Na2SO4, concen-
trated in vacuo to give the residue which was purified by Si CC with
petroleum ether/acetone (97:3) to afford compound 5 (17 mg,
yield 81%) as white amorphous power; 1H NMR (CDCl3,
500 MHz) d 8.00 (1H, d, J = 9.0 Hz), 7.62 (2H, m), 7.54–7.46 (2H,
m), 7.25 (1H, d, J = 7.5 Hz), 7.12 (1H, d, J = 2.1 Hz), 4,24–4.16 (2H,
m), 3.16–3.12 (1H, m), 2.93–2.88 (1H, m), 2.16 (3H, s); 13C NMR
(CDCl3, 125 MHz) d 170.6, 152.1, 147.3, 144.9, 134.0, 133.4,
133.1, 131.1, 131.0, 130.7, 130.2, 130.2, 128.9, 127.3, 127.2,
124.6, 62.2, 30.5, 20.9; ESIMS: m/z 416 [M+Na]+, HRESIMS: calcd
for C19H15NO2Cl3 [M+H]+ 394.0168, found 394.0161.
5.1.9. 3-(2-Azidoethyl)-2,6-dichloro-4-(2-chlorophenyl)quin-
oline (9) and 2-azido-3-(2-azidoethyl)-6-chloro-4-(2-chloro-
phenyl)quinoline (10)
A solution of compound 8 (64 mg, 0.15 mmol) in N,N-dimethyl-
formamide (3 mL) and sodium azide (20 mg, 0.31 mmol) was
heated at 80 °C for 4 h. The mixture was cooled and extracted with
EtOAc (100 mL). The organic layer was washed with brine, dried
with anhydrous Na2SO4, concentrated in vacuo to obtain the resi-
due which was purified by Si CC with petroleum ether/acetone
(100:1) to afford derivatives 9 (29 mg, yield 52%) as white amor-
phous power and 10 (27 mg, yield 47%) as white amorphous
power; Compound 9: 1H NMR (CDCl3, 400 MHz) d 8.00 (1H, d,
J = 8.9 Hz), 7.65–7.61 (2H, m), 7.55–7.47 (2H, m), 7.24 (1H, d,
J = 1.6 Hz), 7.12 (1H, d, J = 2.0 Hz), 3.46–3.42 (2H, m), 3.05–3.00
(1H, m), 2.91–2.85 (1H, m); 13C NMR (CDCl3, 100 MHz) d 151.8,
147.3, 144.9, 134.0, 133.5, 133.1, 131.2, 130.81, 130.78, 130.3,
130.2, 129.0, 127.5, 127.3, 124.6, 49.4, 30.8; ESIMS: m/z 399
[M+Na]+, HRESIMS: calcd for C17H12N4Cl3 [M+H]+ 377.0127, found
377.0132.; Compound 10: 1H NMR (CDCl3, 500 MHz) d 8.70 (1H, d,
J = 8.8 Hz), 7.80 (1H, dd, J = 8.8, 2.1 Hz), 7.66 (1H, m), 7.60–7.53
(2H, m), 7.36 (1H, dd, J = 7.4, 1.7 Hz), 7.24 (1H, d, J = 2.2 Hz),
3.09–3.85 (1H, m), 3.74–3.69 (1H, m), 3.27–3.21 (1H, m), 3.07–
3.01 (1H, m); 13C NMR (CDCl3, 100 MHz) d 151.8, 147.4, 140.2,
134.2, 133.7, 132.8, 131.4, 131.1, 130.4, 128.2, 127.7, 126.9,
125.5, 123.5, 118.4, 49.4, 29.4; ESIMS: m/z 406 [M+Na]+, HRESIMS:
calcd for C17H12N7Cl2 [M+H]+ 384.0531, found 384.0520.
5.1.6. 2-[6-Chloro-4-(2-chlorophenyl)-2-methoxyquinolin-3-yl]
ethanol (6)
To a solution of compound 5 (300 mg, 0.76 mmol) in MeOH/
H2O (15 ml, 4:1) was added K2CO3 (314 mg, 2.28 mmol). The mix-
ture was refluxed and monitored by TLC (petroleum ether/acetone,
4:1), then quenched by 5% HCl, and extracted three times with
50 mL of EtOAc. The EtOAc layer was washed with brine, dried with
anhydrous Na2SO4. Removal of the solvents gave a residue which
was purified by Si CC with petroleum ether/acetone (5:1) to give
compound 6 (241 mg, yield 69%) as white amorphous power; 1H
NMR (CDCl3, 400 MHz) d 7.80 (1H, d, J = 8.8 Hz), 7.56–7.37 (4H,
m), 7.20 (1H, dd, J = 7.2, 2.0 Hz), 7.02 (1H, d, J = 2.3 Hz), 4.12 (3H,
s), 3.70 (2H, m), 2.88–2.81 (1H, m), 2.71–2.62 (1H, m); 13C NMR
(CDCl3, 100 MHz) d 161.1, 145.8, 143.7, 134.8, 133.3, 131.1,
130.0, 129.9, 129.5, 128.7, 127.1, 125.4, 124.4, 122.0, 61.4, 53.8,
31.6, 21.6; ESIMS: m/z 370 [M+Na]+, HRESIMS: calcd for
C
18H16NO2Cl2 [M+H]+ 348.0558, found 348.0554.
5.1.7. 2-[2,6-Dichloro-4-(2-chlorophenyl)quinolin-3-yl] ethanol
(7)
5.1.10. 3-[2-(tert-Butyldiphenylsilyloxy)ethyl]-6-chloro-4-(2-
chlorophenyl)quinolin-2(1H)-one (11)
Compound 1 (909 mg, 2.72 mmol) was dissolved in 15 mL of
DMF, stirred and cooled to 0 °C in an ice bath. N-Ethyldiisopropyl-
amine (DIEA, 35 mg, 0.27 mmol) and tert-butyldiphenylchlorosi-
lane (TBDPSCl, 1.5 g, 5.45 mmol) were added to the solution and
To a solution of compound 5 (55 mg, 0.14 mmol) in MeOH/H2O
(5.0 ml, 4:1) was added NH4OAc (86 mg, 1.11 mmol). The mixture
was refluxed and monitored by TLC (petroleum ether/acetone, 4:1),
then quenched by 5% HCl, and extracted with EtOAc. The combined
EtOAc layer was washed with brine, dried with anhydrous Na2SO4,

1406
R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
the resulting mixture was stirred for 12 h at room temperature.
The reaction mixture was quenched with water and extracted with
EtOAc. The organic layer was washed with 5% HCl and brine, dried
with anhydrous MgSO4, filtered. Removal of the solvents gave a
residue which was purified by Si CC with CHCl3/MeOH (70:1) to
produce compound 11 (1.32 g, yield 86%) as white amorphous
power; 1H NMR (CDCl3, 400 MHz) d 13.1 (1H, s), 7.57 (5H, m),
7.50–7.18 (11H, m), 6.85 (1H, s), 4.10–4.04 (1H, m), 3.98–3.92
(1H, m), 3.07–3.00 (1H, m), 2.79–2.72 (1H, m), 1.04 (9H, s); 13C
NMR (CDCl3, 125 MHz) d 164.1, 146.6, 135.9, 135.42 (C Â 2),
135.40 (C Â 2), 134.4, 133.9 (C Â 2), 133.8, 132.9, 131.1, 130.0,
129.99 (C Â 2), 129.96 (C Â 2), 129.4, 127.8, 127.7, 127.51 (C Â 2),
127.49 (C Â 2), 127.1, 125.3, 117.5, 62.1, 32.0, 27.0 (C Â 3), 19.3;
ESIMS: m/z 572 [M+H]+, HRESIMS: calcd for C33H32NO2SiCl2
[M+H]+ 572.1579, found 572.1585.
(1H, d, J = 8.8 Hz), 7.56–7.22 (6H, m), 7.04 (1H, d, J = 2.2 Hz), 6.96
(2H, m), 5.68 (2H, m), 3.70 (2H, t, J = 6.8 Hz), 2.86–2.79 (1H, m),
2.69–2.62 (1H, m); 13C NMR (CDCl3, 100 MHz) d 163.4, 160.8,
160.2, 146.1, 143.5, 134.8, 133.4, 131.2, 130.6, 130.03, 129.98,
129.9, 129.6, 128.8, 127.1, 125.6, 124.4, 122.1, 112.8, 111.5,
111.3, 61.5, 56.3, 31.6; ESIMS: m/z 482 [M+Na]+, HRESIMS: calcd
for C24H18NO2F2Cl2 [M+H]+ 460.0682, found 460.0679.
5.3.2. 2-[2-(2,6-Dichlorobenzyloxy)-6-chloro-4-(2-chloro-
phenyl) quinolin-3-yl] ethanol (15)
White amorphous power, yield 91% (after chromatography with
petroleum ether/acetone, 80:20); 1H NMR (CDCl3, 500 MHz) d 7.89
(1H, d, J = 8.8 Hz), 7.57–7.52 (2H, m), 7.46–7.39 (4H, m), 7.24 (2H,
m), 7.06 (1H, d, J = 2.2 Hz), 5.86 (1H, d, J = 11.5 Hz), 5.81 (1H, d,
J = 11.5 Hz), 3.69 (2H, t, J = 7.0 Hz), 2.84–2.78 (1H, m), 2.68–2.62
(1H, m); 13C NMR (CDCl3, 125 MHz) d 160.4, 146.1, 143.6, 137.1,
134.8, 133.4, 132.4, 131.2, 130.4, 130.0, 130.0, 129.9, 129.6, 128.8,
128.5, 127.1, 125.7, 124.4, 122.0, 63.5, 61.5, 31.6; ESIMS: m/z 514
[M+Na]+, HRESIMS: calcd for C24H18NO2Cl4 [M+H]+ 492.0091, found
492.0105.
5.2. General procedure for the synthesis of compounds 12 and
13
To a solution of compound 11 (200 mg, 0.35 mmol) in acetone
(5 mL) were added K2CO3 (241 mg, 1.75 mmol), and 2,6-difluorob-
enzyl bromide or 2,6-dichlorobenzyl bromide (250 mg, 1.05 mmol)
at room temperature, The resulting mixture was stirred at room
temperature until the starting material disappeared on the TLC.
The reaction mixture was filtered, concentrated in vacuo to give
the residue which was performed on Si CC to afford the products
(12 and 13).
5.3.3. 3-[2-(tert-Butyldiphenylsilyloxy)ethyl]-6-chloro-4-(2-
chlorophenyl) quinolin-2-yltrifluoro-methanesulfonate (16)
To a solution of compound 11 (57 mg, 0.01 mmol), pyridine
(0.25 mmol, 20 mg), and diisopropylethylamine (29 mg, 0.22
mmol) in dichloromethane (5 mL) trifluoromethanesulfonic anhy-
dride (57 mg, 0.02 mmol) was added. The reaction mixture was
stirred at room temperature for 5 h and evaporated in vacuo to
produce the residue which was purified by Si CC with petroleum
ether/acetone (100:1) to obtain compound 18 (60 mg, yield 86%)
as yellow oil; 1H NMR (CDCl3, 400 MHz) d 7.99 (1H, d, J = 8.8 Hz),
7.57 (9H, m), 7.31–7.24 (5H, m), 7.13 (1H, d, J = 2.2 Hz), 7.01 (1H,
d, J = 7.6 Hz), 3.80–3.68 (2H, m), 3.06–2.99 (1H, m), 2.86–2.79
(1H, m), 0.97 (9H, s); 13C NMR (CDCl3, 100 MHz) d 154.2, 149.8,
142.8, 135.6, 135.42 (C Â 2), 135.40 (C Â 2), 133.8, 133.5, 133.42,
133.38, 133.2, 131.3, 131.1, 130.6, 130.4, 130.2, 129.6 (C Â 2),
128.1, 127.7 (C Â 2), 127.6 (C Â 2), 127.2, 124.6, 122.9, 62.2, 31.3,
26.8 (C Â 3), 19.1; ESIMS: m/z 726 [M+Na]+, HRESIMS: calcd for
5.2.1. 12-(2,6-Difluorobenzyloxy)-3-[2-(tert-butyldiphenyl-
silyloxy)ethyl]-6-chloro-4-(2-chlorophe-nl) quinoline (12)
Colorless oil, yield 54% (after chromatography with petroleum
ether/acetone, 20:1); 1H NMR (CDCl3, 400 MHz) d 7.82 (1H, d,
J = 8.9 Hz), 7.43–7.24 (15H, m), 7.23 (1H, d, J = 8.9 Hz), 6.97 (1H,
d, J = 2.4 Hz), 6.89 (2H, m), 5.58 (2H, s), 3.79–3.74 (2H, m), 2.93–
2.86 (1H, m), 2.71–2.64 (1H, m), 0.92 (9H, s); 13C NMR (CDCl3,
100 MHz)
d 163.3, 160.9, 160.3, 145.9, 143.5, 135.3, 134.8,
133.92, 133.86, 133.3, 131.5, 130.3, 130.2, 129.8, 129.4, 129.3,
128.8, 127.4, 126.9, 125.6, 124.4, 122.2, 111.42, 111.35, 111.2;
ESIMS: m/z 720 [M+Na]+, HRESIMS: calcd for C40H36NO2F2SiCl2
[M+H]+ 698.1860, found 698.1842.
C
34H31NO4F3SCl2Si [M+H]+ 704.1072, found 704.1054.
5.4. General procedure for the synthesis of compounds 17–20
5.2.2. 2-(2,6-Dichlorobenzyloxy)-3-(2-(tert-butyldiphenylsi-
lyloxy)ethyl)-6-chloro-4-(2-chloroph-enyl)quinoline (13)
Colorless oil, yield 49% (after chromatography with petroleum
ether/acetone, 20:1); 1H NMR (CDCl3, 500 MHz) d 7.90 (2H, d,
J = 8.5 Hz), 7.53 (2H, m), 7.42 (5H, m), 7.35 (4H, m), 7.29–7.21
(6H, m), 7.14 (1H, dd, J = 7.6, 1.6 Hz), 7.01 (1H, d, J = 7.4 Hz), 5.77
(2H, m), 3.81 (2H, m), 2.92–2.87 (1H, m), 2.73–2.63 (1H, m), 0.91
(9H, s); 13C NMR (CDCl3, 125 MHz) d 160.5, 146.1, 143.4, 137.1,
135.3, 134.7 (C Â 4), 132.5, 131.6, 130.2, 129.8, 129.7, 129.5,
129.4, 129.3, 128.7, 128.3, 127.5, 127.4, 126.9, 125.7, 124.5,
122.3, 63.5, 62.5, 31.6, 26.8, 19.2; ESIMS: m/z 730 [M+H]+, HRE-
SIMS: calcd for C40H36NO2Cl4Si [M+H]+ 730.1269, found 730.1271.
Compound 16 (58 mg, 0.082 mmol), amines (0.16 mmol) and
diisopropylamine (22 mg, 0.16 mmol) in acetonitrile (5 mL) was
refluxed for 5 h. The solvent was removed in vacuo to provide a
residue which was followed by Si CC to yield the products (17–20).
5.4.1. 3-[2-(tert-Butyldiphenylsilyloxy)ethyl]-6-chloro-4-(2-
chlorophenyl)-2-(piperidin-1-yl) quinoline (17)
Choroless oil, yield 56% (after chromatography with petroleun
ethher/EtOAc, 100:1); 1H NMR (CDCl3, 500 MHz) d 7.75 (1H, d,
J = 11.0 Hz), 7.44–7.15 (14H, m), 6.95 (1H, dd, J = 9.4, 2.0 Hz), 6.88
(1H, d, J = 2.8 Hz), 3.66–3.56 (2H, m), 3.12–3.05 (4H, m) 2.99–
2.92 (1H, m), 2.78–2.71 (1H, m), 1.68–1.54 (6H, m), 0.86 (9H, s);
13C NMR (CDCl3, 100 MHz) d 163.0, 145.6, 144.4, 135.6, 135.34
(C Â 4), 135.33, 133.73, 133.69, 133.4, 131.6, 129.9, 129.7, 129.5,
129.4 (C Â 2), 129.2, 127.5 (C Â 4), 126.8, 126.5, 125.8, 124.1,
62.8, 52.3 (C Â 2), 33.1, 26.8 (C Â 3), 26.1 (C Â 2), 24.6, 19.1; ESIMS:
m/z 639 [M+H]+, HRESIMS: calcd for C38H41N2OCl2Si [M+H]+
639.2365, found 639.2357.
5.3. General procedure for the synthesis of compounds 14 and
15
To a solution of compounds (12 and 13) (0.14 mmol) in THF
(3 mL) at 0 °C was added tetrabutylammonium fluoride (0.28
mmol, 280 lL) in one portion. After stirring at room temperature
for 12 h, the solvent was evaporated in vacuo to give the residue
which was performed on Si CC to afford the products (14 and 15).
5.4.2. 4-{3-[2-(tert-Butyldiphenylsilyloxy)ethyl]-6-chloro-4-(2-
chlorophenyl)quinolin-2-yl}mor-ph-oline (18)
Choroless oil, yield 82% (after chromatography with petroleum
ether/EtOAc, 30:1); 1H NMR (CDCl3, 400 MHz) d 7.84 (1H, d,
J = 8.6 Hz), 7.54–7.36 (9H, m), 7.30–7.26 (5H, m), 7.03 (1H, d,
5.3.1. 2-[2-(2,6-Difluorobenzyloxy)-6-chloro-4-(2-chlorophenyl)
quinolin-3-yl]ethanol (14)
White amorphous power, yield 90% (after chromatography with
petroleum ether/acetone, 80:20); 1H NMR (CDCl3, 400 MHz) d 7.86

R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
1407
J = 7.6 Hz), 6.98 (1H, d, J = 2.0 Hz), 3.89–3.79 (4H, m), 3.75–3.63
(2H, m), 3.35–3.31 (2H, m), 3.22–3.18 (2H, m), 3.07–3.00 (1H,
m), 2.87–2.80 (1H, m), 0.94 (9H, s); 13C NMR (CDCl3, 100 MHz) d
161.6, 145.0, 144.4, 135.3, 133.5, 133.3, 131.5, 130.4, 129.9,
129.8, 129.6, 129.53, 129.48, 127.5, 126.9, 125.98, 125.96, 124.1,
67.0, 62.6, 51.3, 32.9, 26.7, 19.1; EIMS: m/z (%) 640 ([M]+, 5), 583
(100), 327 (50), 199 (93), HREIMS: calcd for C37H38N2O2Cl2Si [M]+
640.2080, found 640.2069.
3.22 (2H, m), 3.18–3.12 (2H, m), 2.85–2.78 (1H, m), 2.69–2.62
(1H, m); 13C NMR (CD3OD, 125 MHz) d 161.3, 146.1, 144.0, 134.9,
133.0, 131.0, 130.9, 129.9, 129.8, 129.6, 129.3, 127.0, 126.6,
126.1, 124.0, 66.6 (C Â 2), 61.5, 51.2 (C Â 2), 32.4; EIMS: m/z 402
([M]+, 85), 367 (100), 282 (83), 199 (75), 86 (100), HREIMS: calcd
for C21H20N2O2Cl2 [M]+ 402.0902, found 402.0904.
5.5.3. 2-(6-Chloro-4-(2-chlorophenyl)-2-(piperazin-1-yl)quin-
olin-3-yl)ethanol (23)
5.4.3. 3-[2-(tert-Butyldiphenylsilyloxy)ethyl]-6-chloro-4-(2-
chlorophenyl)-2-(piperazin-1-yl) quinoline (19)
White amorphous power, yield 76% (after chromatography
with CHCl3/CH3OH/Et2NH, 500:50:1); 1H NMR (CDCl3, 400 MHz)
d 7.88 (1H, d, J = 8.9 Hz), 7.59–7.52 (2H, m), 7.48–7.40 (2H, m),
7.19 (1H, dd, J = 7.2, 1.8 Hz), 7.02 (1H, d, J = 2.2 Hz), 3.77–3.71
(1H, m), 3.62–5.57 (1H, m), 3.38–3.13 (8H, m), 3.00–2.92 (1H,
m), 2.83–2.75 (1H, m); 13C NMR (CDCl3, 100 MHz) d 161.9,
145.8, 144.4, 135.2, 133.3, 131.3, 131.2, 130.1, 130.0, 129.9,
129.8, 128.1, 127.2, 126.5, 124.3, 63.0, 52.3 (C Â 2), 45.8
(C Â 2), 32.5; EIMS: m/z 401 ([M]+, 15), 333 (100), 297 (85), 83
(25), HRESIMS: calcd for C21H21N3OCl2 [M]+ 401.1062, found
401.1062.
White amorphous power, yield 89% (after chromatography
with petroleum ether/EtOAc/Et2NH (200:1:0.5); 1H NMR (CDCl3,
400 MHz) d 7.83 (1H, d, J = 8.9 Hz), 7.51–7.39 (9H, m), 7.38–
7.28 (5H, m), 7.03 (1H, dd, J = 7.5, 1.4 Hz), 6.97 (1H, d,
J = 2.2 Hz), 3.73–3.65 (2H, m), 3.35–3.25 (2H, m), 3.22–3.12
(2H, m), 3.08–3.00 (5H, m), 2.90–2.80 (1H, m), 0.94 (9H, m);
13C NMR (CDCl3, 100 MHz) d 162.1, 145.8, 144.4, 135.4, 135.3,
133.6, 133.3, 131.5, 130.2, 129.9, 129.8, 129.5, 129.4, 127.5,
126.8, 126.2, 126.0, 124.1, 62.7, 52.1, 45.9, 32.9, 26.7, 19.1; EIMS:
m/z 639 ([M]+, 33), 571 (82), 535 (82), 327 (100), 199 (93), 135
(65), HREIMS: calcd for C37H39N3OCl2Si [M+H]+ 639.2239, found
639.2206.
5.5.4. 2-[2-(1H-Benzo[d][1,2,3]triazol-1-ylamino)-6-chloro-4-(2-
chlorophenyl)quinolin-3-yl]ethan-nol (24)
Colorless oil, yield 50% (after chromatography with petroleum
ether/acetone, 50:50); 1H NMR (CDCl3, 400 MHz) d 7.50 (1H, d,
J = 7.5 Hz), 7.40–7.23 (7H, m), 7.13 (1H, d, J = 6.8 Hz), 6.75 (2H,
m), 3.29 (2H, m), 2.69–2.64 (1H, m), 2.52–2.48 (1H, m); 13C NMR
(CDCl3, 100 MHz) d 163.9, 146.7, 135.4, 134.1, 132.7, 130.7,
130.3, 130.2, 130.0, 128.3, 128.2, 127.72, 127.67, 127.4, 127.3,
127.2, 125.4, 121.2, 116.9, 115.9, 115.7, 61.2, 31.4; ESI: m/z 450
[M+H]+, HREIMS: calcd for C23H18N5OCl2 [M+H]+ 450.0888, found
450.0879.
5.4.4. N-(1H-Benzo[d][1,2,3]triazol-1-yl)-3-[2-(tert-butyldiphen-
ylsilyloxy)ethyl]-6-chloro-4-(2chlorophenyl) quinolin-2-amine
(20)
White amorphous power, yield 42% (after chromatography with
petroleum ether/EtOAc/Et2NH (50:50:0.1); 1H NMR (CDCl3,
500 MHz) d 7.65 (1H, d, J = 6.0 Hz), 7.61 (1H, d, J = 6.4 Hz), 7.46–
7.16 (17H, m), 7.03 (1H, d, J = 7.4 Hz), 6.70 (1H, d, J = 2.0 Hz),
3.84–3.73 (2H, m), 2.88–2.83 (1H, m), 2.61–2.55 (1H, m), 0.90
(9H, s); 13C NMR (CDCl3, 125 MHz) d 164.1, 146.9, 135.6, 135.4,
135.3, 134.7, 134.0, 133.3, 132.7, 130.4, 130.3, 130.1, 129.5,
129.3, 128.3, 125.4, 121.3, 117.1, 61.9, 31.8, 26.7, 26.6, 26.4; ESI:
m/z 688 [M+H]+, HREIMS: calcd for C39H36N5OCl2Si [M+H]+
688.2066, found 688.2063.
5.6. Determination of HBV replication23
HepG 2.2.15 cells were seeded in 24 well culture plates at a den-
sity of 5 Â 105 cells per well. Every 2 days, medium was changed.
After 6 days, compounds were added to the cell cultures, and fresh
medium was fed every other day for another 6 days. Cells were col-
lected and total DNA was isolated by using TIANamp Gemomic
DNA Kit (TIANGEN, Biotech Co., Ltd, China) following the manufac-
turer’s instructions. For detection of HBV DNA, a real-time PCR as-
say was used.
5.5. General procedure for the synthesis of compounds 21–24
To a solution of compound 17–20 (0.078 mmol) in THF (3 mL) at
0 °C was added tetrabutylammonium fluoride (0.16 mmol, 160 lL)
in one portion. After stirring at room temperature for 12 h, the sol-
vent was evaporated in vacuo and the residue was performed on Si
CC to give compounds 21–24.
5.7. Analysis of secreted HBV antigens24,25
5.5.1. 2-[6-Chloro-4-(2-chlorophenyl)-2-(piperidin-1-yl)quino-
lin-3-yl]ethanol (21)
Medium from HepG 2.2.15 cells was collected, centrifuged at
6000g to remove cellular debris, transferred to clean tubes. The
levels of HBsAg and HBeAg were determined utilizing commer-
cially available quantitative ELISA test kits (Autobio diagnostics
Co., LTD, China.) and measured with a microplate reader (model
680, Bio-Rad, USA).
White amorphous power, yield 81% (after chromatography with
petroleum ether/acetone, 80:20); 1H NMR (CDCl3, 500 MHz) d 7.90
(1H, d, J = 8.9 Hz), 7.58–7.52 (2H, m), 7.45–7.41 (2H, m), 7.19 (1H,
d, J = 7.3 Hz), 7.04 (1H, d, J = 1.8 Hz), 3.76 (1H, m), 3.59 (1H, m),
3.30 (2H, m), 3.18 (2H, m), 2.80 (1H, m), 2.51 (1H, m), 1.80 (4H,
m), 1.67 (2H, m); 13C NMR (CDCl3, 125 MHz) d 162.8, 145.4,
144.3, 135.2, 134.7, 133.2, 131.1, 130.0, 129.9, 129.8, 129.6,
128.9, 127.1, 126.5, 124.2, 63.2, 52.5 (C Â 2), 32.4, 25.7 (C Â 2),
24.0; EIMS: m/z (%) 400 ([M]+, 55), 366 (100), 251 (63), 214 (70),
84 (87), HREIMS: calcd for C22H22N2OCl2 [M]+ 400.1109, found
400.1119.
Acknowledgments
The work was supported by grants from National Natural
Science Foundation of China for Distinguished Young Scholars
(No. 81025023), Xibu Zhiguang Joint-Scholarship of Chinese
Academy of Sciences, the External Cooperation Program of Chi-
nese Academy of Sciences (No. GJHI200818), and CAS–Croucher
Fund (CAS-CF07/08.SC03). The authors are grateful to the staff
of the analytical group of the State Key Laboratory of Phyto-
chemistry and Plant Resources in West China, Kunming Institute
of Botany, Chinese Academy of Sciences, for measurements of all
spectra.
5.5.2. 2-[6-Chloro-4-(2-chlorophenyl)-2-morpholinoquinolin-3-
yl]ethanol (22)
White amorphous power, yield 62% (after chromatography with
with CHCl3/CH3OH, 50:1); 1H NMR (CD3OD, 400 MHz) d 7.77 (1H,
d, J = 8.9 Hz), 7.48–7.30 (4H, m), 7.11 (1H, dd, J = 8.9, 2.2 Hz), 6.90
(1H, d, J = 2.2 Hz), 3.90–3.80 (4H, m), 3.58–3.46 (2H, m), 3.28–

1408
R.-H. Guo et al. / Bioorg. Med. Chem. 19 (2011) 1400–1408
14. Zhang, Q.; Jiang, Z. Y.; Luo, J.; Liu, J. F.; Ma, Y. B.; Guo, R. H.; Zhang, X. M.; Zhou,
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