Synthesis and antitumor activity evaluation of pyrimidine analogues bearing urea moiety

Article abstract of DOI:10.1002/cjoc.201400095

A series of 4-anilino-6-phenylpyrimidines containing urea moiety were synthesized and the structures of all products were confirmed by ¹H NMR, ¹³C NMR and HRMS. The antiproliferative activities of these compounds were evaluated against three human tumor cell lines (MGC-803, MCF-7 and EC-109) by applying the MTT assay method. compounds 4a, 4b and 6a showed the most effective activity, among which, 6a was more cytotoxic than 5-fluorouracil against all tested human cancer cell lines with IC₅₀ values ranging from 1.80 to 2.72 μmol·L^-1. A series of 4-anilino-6-phenylpyrimidines containing urea moiety were synthesized. The antiproliferative activities of these compounds were evaluated against three human tumor cell lines (MGC-803, MCF-7 and EC-109) by applying the MTT assay method. compounds 4a, 4b and 6a showed most effective activity, among which, 6a was more cytotoxic than 5-fluorouracil against all tested three human cancer cell lines with IC₅₀ values ranging from 1.80 to 2.72 μmol·L^-1. Copyright

Full text of DOI:10.1002/cjoc.201400095

FULL PAPER
DOI: 10.1002/cjoc.201400095
Synthesis and Antitumor Activity Evaluation of Pyrimidine
Analogues Bearing Urea Moiety
Kunpeng Shao, Xuyao Zhang, Xiaosong Zhang, Dengqi Xue, Liying Ma,
Qiurong Zhang,* and Hongmin Liu*
School of Pharmaceutical Sciences and New Drug Research & Development Center, Zhengzhou University,
Zhengzhou, Henan 450001, China
A series of 4-anilino-6-phenylpyrimidines containing urea moiety were synthesized and the structures of all
1
products were confirmed by H NMR, 13C NMR and HRMS. The antiproliferative activities of these compounds
were evaluated against three human tumor cell lines (MGC-803, MCF-7 and EC-109) by applying the MTT assay
method. compounds 4a, 4b and 6a showed the most effective activity, among which, 6a was more cytotoxic than
5-fluorouracil against all tested human cancer cell lines with IC50 values ranging from 1.80 to 2.72 μmol•L－
.
1
Keywords synthesis, pyrimidine, urea, antitumor
Introduction
Figure 1). The synthetic strategy to prepare the target
compounds is depicted in Scheme 1. The structure-
activity relationship (SAR) of these compounds was
also discussed.
Cancer is a leading cause of death worldwide. The
pharmacological fight against cancer has made signifi-
cant progress in the last twenty years. In 2012 (October
1, 2011－September 30, 2012), 35 novel drugs were
approved by the FDA, among which, 10 (28.57%) were
used for the treatment of cancer.[1] Although many
chemotherapeutic agents have been developed to treat
different kinds of cancer effectively, some side effects
could happen simultaneously. Therefore novel mole-
cules to fight this disease are still urgently needed.[2,3]
Pyrimidine is found as a core structure in a large va-
riety of compounds that exhibit important biological
activity.[4,5] Many papers have reported that pyrimidine
derivatives showed impressive anticancer activity[6-9]
and several members of this class have earned valued
places in chemotherapy as effective agents, like
5-fluorouracil, tegafur, carmofur and fluoroadenosine.
Among them, 4-anilino-6-phenyl-pyrimidines (I, Figure
1) play an important role in the development of anti-
cancer drugs.[10,11]
On the other hand, urea hybrids with a wide range of
activities against various leukemias and solid tumors.[12]
2-Substituted-N-(arylcarbamoyl)acetamide derivatives
(II, Figure 1) are an important class of urea derivatives
and have received much attention. Several promising
antitumor active agents were found to contain the scaf-
fold.[13,14]
With this in view, here we report the synthesis and
biological activity of pyrimidine derivatives bearing
2-substituted-N-(arylcarbamoyl)acetamide moiety (III,
O
O
R2
Ar
R
HN
N
N
H
H
N
II
R1
N
R3
I
R
HN
N
H
H
X
N
N
S
N
O
O
III
Figure 1 The structures of compounds I, II and III.
Experimental
General
Reagents and solvents were purchased from com-
mercial sources and were used without further purifica-
tion. Thin-layer chromatography (TLC) was carried out
on glass plates coated with silica gel (Qingdao Haiyang
Chemical Co., G60F-254) and visualized by UV light
(254 nm). The products were purified by column chro-
matography over silica gel (Qingdao Haiyang Chemical
Co., 200－300 mesh). Melting points were determined
on an X-5 micromelting apparatus and are uncorrected.
All the NMR spectra were recorded with a Bruker
*
E-mail: liuhm@zzu.edu.cn, zqr406@sina.com; Tel.: 0086-0371-67781739; Fax: 0086-0371-67781739
Received February 21, 2014; accepted April 13, 2014; published online May 22, 2014.
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cjoc.201400095 or from the author.
Chin. J. Chem. 2014, 32, 443—447
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Shao et al.
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Scheme 1 The synthesis of pyrimidines analogues bearing urea moiety
OH
S
O
O
OH
N
a
N
+
H2N
NH2
Ph
O
N
H
H
HS
N
Ph
e
d
X
N
N
S
1
H
H
O
O
X
N
N
b
c
O
NH2
Cl
Cl
Cl
Cl
3a 3b
O
O
O
O
2a 2b
R
N
N
N
H
H
N
H
H
N
X
N
f
X
N
S
S
N
O
O
O
O
4a 4b
5a 5k, 6a 6c
Reagents and conditions: (a) KOH, EtOH, reflux; (b) NH3·H2O, 0 ℃; (c) i) Oxalyl chloride, 1,2-dichloroethane, 90 ℃; ii) 2-aminopyridine or
aniline, 0 ℃; (d) KOH, H2O-acetone (2:1), 55－60 ℃; (e) POCl3, 90 ℃; (f) substituted anilines, AcOH, 90 ℃
DPX 400 MHz spectrometer. Chemical shifts (δ) are
given relative to TMS. High-resolution mass spectra
(HRMS) were recorded on a Waters Micromass Q-T of
Micromass spectrometer by electrospray ionization
(ESI). The synthesized compounds were named using
ChemDraw Ultra software (v 12.0).
the pure product.
2-((4-Hydroxy-6-phenylpyrimidin-2-yl)thio)-N-
(pyridin-2-ylcarbamoyl)acetamide (3a) Yield 85.8%,
1
white solid, m.p. 221－222 ℃; H NMR (400 MHz,
DMSO-d6) δ: 12.75 (s, 1H), 11.34 (s, 1H), 10.70 (s, 1H),
8.33－8.20 (m, 1H), 8.04 (d, J＝7.2 Hz, 2H), 7.98 (d,
J＝8.2 Hz, 1H), 7.86－7.78 (m, 1H), 7.44 (q, J＝7.3 Hz,
1H), 7.38 (t, J＝7.3 Hz, 2H), 7.12 (dd, J＝6.9, 5.3 Hz,
1H), 6.72 (s, 1H), 4.26 (s, 2H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.1, 164.8, 162.5, 161.1, 151.2, 150.8,
148.6, 139.0, 136.2, 131.1, 129.0, 127.2, 120.1, 113.5,
104.2, 35.5. HR-MS (ESI) calcd for C18H15N5O3S [M＋
H]＋: 382.0974, found 382.0948.
General procedure to synthesize compounds 2a－2b
To a solution of compound 1 (1.8 g, 19.4 mmol) in
anhydrous 1,2-dichloroethane (20 mL) was added oxalyl
chloride (2 mL) at 0 ℃, then refluxed on oil bath at 90
℃ for 4 h. The reaction mixture was then cooled to 0
℃, and 2-aminopyridine or aniline (19.40 mmol) was
added into the reaction mixture. The reaction mixture
was stirred for another 5 min. Upon completion, the
solid was filtrated and washed with 1,2-dichloroethane
to yield the pure product.
2-((4-Hydroxy-6-phenylpyrimidin-2-yl)thio)-N-
(phenylcarbamoyl)acetamide (3b)
Yield 89.8%,
1
white solid, m.p. 208－209 ℃; H NMR (400 MHz,
DMSO-d6) δ: 12.87 (s, 1H), 11.13 (s, 1H), 10.34 (s, 1H),
8.05 (d, J＝7.4 Hz, 2H), 7.51 (d, J＝7.9 Hz, 2H), 7.45
(d, J＝7.1 Hz, 1H), 7.40 (t, J＝7.4 Hz, 2H), 7.31 (t, J＝
7.8 Hz, 2H), 7.08 (t, J＝7.4 Hz, 1H), 6.73 (s, 1H), 4.24
(s, 2H). HR-MS (ESI) calcd for C19H16N4O3S [M＋H]＋:
381.1021, found 381.1023.
2-Chloro-N-(pyridin-2-ylcarbamoyl)acetamide
1
(2a) Yield 90.7%, white solid; H NMR (400 MHz,
CDCl3) δ: 10.63 (s, 1H), 8.78 (s, 1H), 8.36 (d, J＝4.1 Hz,
1H), 8.08 (d, J＝6.9 Hz, 1H), 7.80－7.68 (m, 1H), 7.10
(dd, J＝6.9, 5.2 Hz, 1H), 4.24 (s, 2H). HR-MS (ESI)
calcd for C8H8ClN3O2 [M ＋ H] ＋ : 214.0378, found
214.0379.
General procedure to synthesize compounds 4a－4b
2-Chloro-N-(phenylcarbamoyl)acetamide (2b)
Yield 86.3%, white solid; 1H NMR (400 MHz,
DMSO-d6) δ: 10.92 (s, 1H), 10.18 (s, 1H), 7.57－7.50
(m, 2H), 7.34 (t, J＝7.9 Hz, 2H), 7.11 (t, J＝7.4 Hz, 1H),
4.41 (s, 2H); 13C NMR (100 MHz, DMSO-d6) δ: 169.0,
150.7, 137.9, 129.4, 124.2, 120.2, 43.7. HR-MS (ESI)
calcd for C9H9ClN2O2 [M ＋ H] ＋ : 213.0431, found
213.0430.
In an ice bath, phosphorous oxychloride (10 mL)
was added dropwise with gentle stirring to compound 3a
or 3b (10.12 mmol). The reaction mixture was stirred at
room temperature for 30 min, and then stirred at 90℃.
Upon completion, after cooling, the reaction mixture
was poured with continuous stirring onto crushed ice.
The formed solid was collected by vacuum filtration,
washed with water to yield the pure product.
2-((4-Chloro-6-phenylpyrimidin-2-yl)thio)-N-
(pyridin-2-ylcarbamoyl)acetamide (4a) Yield 91.2%,
white solid, m.p. 192－193 ℃; H NMR (400 MHz,
DMSO-d6) δ: 11.36 (s, 1H), 10.70 (s, 1H), 8.27 (d, J＝
4.6 Hz, 1H), 8.22 (d, J＝7.4 Hz, 2H), 8.02 (s, 1H), 7.98
(d, J＝8.3 Hz, 1H), 7.82 (t, J＝7.8 Hz, 1H), 7.57 (t, J＝
7.3 Hz, 1H), 7.49 (t, J＝7.5 Hz, 2H), 7.12 (dd, J＝6.8,
5.4 Hz, 1H), 4.30 (s, 2H); 13C NMR (100 MHz,
General procedure to synthesize compounds 3a－3b
1
To a solution of compound 1 (2.0 g, 10.0 mmol) and
potassium hydroxide (0.6 g, 10.0 mmol) in water (40
mL) was slowly added compound 2a or 2b (10.0 mmol)
dissolved in acetone (10 mL), and the reaction was
stirred at 50 ℃. Upon completion, the solid was fil-
trated and washed with water then with acetone to yield
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Chin. J. Chem. 2014, 32, 443—447

Synthesis and Antitumor Activity Evaluation of Pyrimidine Analogues Bearing Urea Moiety
DMSO-d6) δ: 171.2, 171.1, 165.6, 161.6, 151.2, 150.8,
148.5, 139.1, 134.8, 132.5, 129.4, 128.0, 120.1, 113.5,
113.2, 36.1. HR-MS (ESI) calcd for C18H14ClN5O2S [M
＋H]＋: 400.0635, found 400.0632.
11.8, 6.2 Hz, 1H), 7.01 (s, 1H), 6.87 (d, J＝7.4 Hz, 1H),
4.20 (s, 2H), 2.31 (s, 3H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.7, 169.4, 161.4, 161.2, 151.0, 150.8,
148.0, 139.7, 139.6, 138.5, 136.7, 131.0, 129.2, 129.1,
126.9, 124.1, 121.1, 120.1, 117.8, 113.8, 99.1, 35.8,
21.6. HR-MS (ESI) calcd for C25H22N6O2S [M＋H]＋:
471.1603, found 471.1605.
2-((4-Chloro-6-phenylpyrimidin-2-yl)thio)-N-
(phenylcarbamoyl)acetamide (4b)
Yield 92.1%,
1
white solid, m.p. 201－202 ℃; H NMR (400 MHz,
DMSO-d6) δ: 11.17 (s, 1H), 10.32 (s, 1H), 8.23 (d, J＝
7.5 Hz, 2H), 8.03 (s, 1H), 7.58 (t, J＝7.3 Hz, 1H), 7.50
(t, J＝7.4 Hz, 4H), 7.31 (t, J＝7.9 Hz, 2H), 7.08 (t, J＝
7.4 Hz, 1H), 4.27 (s, 2H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.2, 170.9, 165.6, 161.6, 151.0, 137.9,
134.8, 132.6, 129.4, 128.0, 124.2, 120.1, 113.2, 36.0.
HR-MS (ESI) calcd for C19H15ClN4O2S [M＋H]＋ :
399.0682, found 399.0673.
2-((4-((4-Butylphenyl)amino)-6-phenylpyrimidin-
2-yl)thio)-N-(pyridin-2-ylcarbamoyl)aceta-mide (5d)
1
Yield 89.1%, white solid, m.p. 231－232 ℃; H NMR
(400 MHz, DMSO-d6) δ: 11.29 (s, 1H), 10.81 (s, 1H),
9.96 (s, 1H), 8.35－8.23 (m, 1H), 8.06－7.95 (m, 3H),
7.91－7.84 (m, 1H), 7.53 (t, J＝8.1 Hz, 2H), 7.52－7.43
(m, 3H), 7.21－7.12 (m, 3H), 7.01 (s, 1H), 4.22 (s, 2H),
1.50 (dt, J＝15.2, 7.5 Hz, 2H), 1.27 (dq, J＝14.6, 7.3 Hz,
2H), 0.87 (t, J＝7.3 Hz, 3H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.2, 169.1, 160.9, 160.2, 150.8, 150.5,
146.8, 140.6, 137.6, 137.1, 135.9, 131.2, 129.3, 129.0,
127.1, 120.7, 120.2, 114.5 (s), 99.4, 36.0, 34.7, 33.5,
22.2, 14.2. HR-MS (ESI) calcd for C28H28N6O2S [M＋
H]＋: 513.2073, found 513.2070.
General procedure to synthesize compounds 5a－5k
and 6a－6c
To a well stirred solution of the appropriate amine
(5.30 mmol) in acetic acid glacial (3 mL), equimolar
amount of compound 4a or 4b (5.30 mmol) was added.
The reaction mixture was stirred at 90 ℃. Upon com-
pletion, the solvent was then removed by distillation
under reduced pressure and the remained solid was
washed with cold water and purified either by recrystal-
lization or by silica gel column chromatography.
2-((4-((4-Methoxyphenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5e) Yield 84.5%, white solid, m.p. 201－202
1
℃; H NMR (400 MHz, DMSO-d6) δ: 11.25 (s, 1H),
10.77 (s, 1H), 9.68 (s, 1H), 8.28 (d, J＝4.5 Hz, 1H),
7.98 (t, J＝7.3 Hz, 3H), 7.83 (t, J＝7.8 Hz, 1H), 7.52 (d,
J＝8.6 Hz, 2H), 7.47 (t, J＝6.3 Hz, 3H), 7.16－7.10 (m,
1H), 6.94 (d, J＝8.9 Hz, 2H), 6.89 (s, 1H), 4.18 (s, 2H),
3.73 (s, 3H); 13C NMR (100 MHz, DMSO-d6) δ: 171.6,
169.5, 161.2, 155.7, 151.2, 150.9, 148.3, 139.3, 136.8,
132.6, 130.9, 129.2, 126.9, 122.5, 120.1, 114.5, 113.6,
98.4, 55.6, 35.9. HR-MS (ESI) calcd for C25H22N6O3S
[M＋H]＋: 487.1552, found 487.1551.
2-((4-Phenyl-6-(phenylamino)pyrimidin-2-yl)-
thio)-N-(pyridin-2-ylcarbamoyl)acetamide (5a)
1
Yield 70.3%, white solid, m.p. 231－232 ℃; H NMR
(400 MHz, DMSO-d6) δ: 11.28 (s, 1H), 10.77 (s, 1H),
9.83 (s, 1H), 8.28 (d, J＝4.8 Hz, 1H), 8.00 (dd, J＝7.7,
1.7 Hz, 3H), 7.83 (t, J＝7.8 Hz, 1H), 7.66 (d, J＝8.0 Hz,
2H), 7.48 (dd, J＝12.5, 6.8 Hz, 3H), 7.36 (t, J＝7.9 Hz,
2H), 7.16－7.10 (m, 1H), 7.05 (t, J＝7.4 Hz, 1H), 6.99
(s, 1H), 4.20 (s, 2H); 13C NMR (100 MHz, DMSO-d6) δ:
171.7, 169.5, 161.5, 161.2, 151.2, 150.9, 148.3, 139.9,
139.3, 136.8, 131.0, 129.3, 126.9, 123.2, 120.4, 120.1,
113.6 99.1, 35.9. HR-MS (ESI) calcd for C24H20N6O2S
[M＋H]＋: 457.1447, found 457.1450.
2-((4-((2-Methoxyphenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5f) Yield 88.9%, yellow solid, m.p. 189－190
1
℃; H NMR (400 MHz, DMSO-d6) δ: 11.26 (s, 1H),
10.80 (s, 1H), 9.08 (s, 1H), 8.29 (d, J＝4.0 Hz, 1H),
8.05－7.95 (m, 3H), 7.92 (d, J＝7.7 Hz, 1H), 7.89－
7.83 (m, 1H), 7.53－7.39 (m, 3H), 7.15 (dd, J＝6.6, 5.5
Hz, 2H), 7.09 (dd, J＝9.7, 7.8 Hz, 2H), 7.03－6.93 (m,
1H), 4.17 (s, 2H), 3.85 (s, 3H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.4, 169.0, 161.6, 160.9, 151.3, 150.8,
150.7, 147.3, 140.3, 136.4, 129.3, 127.5, 127.0, 125.3,
123.6, 120.8, 120.2, 114.1, 112.0, 99.2, 56.1, 35.8.
2-((4-Phenyl-6-(p-tolylamino)pyrimidin-2-yl)thio)-
N-(pyridin-2-ylcarbamoyl)acetamide (5b)
Yield
1
82.6%, white solid, m.p. 204－205 ℃; H NMR (400
MHz, DMSO-d6) δ: 11.30 (s, 1H), 10.82 (s, 1H), 9.97 (s,
1H), 8.30 (d, J＝4.0 Hz, 1H), 8.07－7.93 (m, 3H),
7.93－7.84 (m, 1H), 7.62－7.40 (m, 5H), 7.16 (dd, J＝
11.0, 7.8 Hz, 3H), 7.00 (s, 1H), 4.21 (s, 2H), 2.24 (s,
3H); 13C NMR (100 MHz, DMSO-d6) δ: 171.1, 168.9,
160.9, 150.8, 150.2, 146.3, 141.2, 136.7, 135.6, 132.8,
131.2, 129.6, 129.3, 127.1, 120.9, 120.3, 114.5, 99.4,
36.0, 20.9. HR-MS (ESI) calcd for C25H22N6O2S [M＋
H]＋: 471.1603, found 471.1605.
HR-MS (ESI) calcd for C25H22N6O3S [M ＋ H] ＋
:
487.1552, found 487.1548.
2-((4-((4-Fluorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5g) Yield 80.1%, white solid, m.p. 215－216
1
2-((4-Phenyl-6-(m-tolylamino)pyrimidin-2-yl)-
℃; H NMR (400 MHz, DMSO-d6) δ: 11.36 (s, 1H),
thio)-N-(pyridin-2-ylcarbamoyl)acetamide
(5c)
10.90 (s, 1H), 10.23 (s, 1H), 8.31 (d, J＝4.3 Hz, 1H),
7.99 (t, J＝9.4 Hz, 3H), 7.93 (t, J＝7.7 Hz, 1H), 7.69
(dd, J＝8.1, 4.6 Hz, 3H), 7.48 (d, J＝6.5 Hz, 3H), 7.18
(t, J＝8.4 Hz, 3H), 7.05 (s, 1H), 4.22 (s, 2H); 13C NMR
(100 MHz, DMSO-d6) δ: 171.2, 169.0, 160.9, 160.3,
159.6, 157.3, 150.8, 149.9, 145.7, 141.7, 135.8, 131.2,
1
Yield 80.8%, white solid, m.p. 205－206 ℃; H NMR
(400 MHz, DMSO-d6) δ: 10.79 (s, 1H), 9.84 (s, 1H),
8.28 (d, J＝4.4 Hz, 1H), 7.99 (d, J＝6.5 Hz, 3H), 7.84 (t,
J＝7.8 Hz, 1H), 7.53 (d, J＝8.0 Hz, 1H), 7.50－7.42 (m,
3H), 7.40 (s, 1H), 7.24 (t, J＝7.8 Hz, 1H), 7.13 (dd, J＝
Chin. J. Chem. 2014, 32, 443—447
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130.0, 129.3, 127.1, 122.5, 120.3, 115.9, 115.7, 114.8,
99.4, 36.0. HR-MS (ESI) calcd for C24H19FN6O2S [M＋
H]＋: 475.1352, found 475.1345.
DMSO-d6) δ: 11.05 (s, 1H), 10.38 (s, 1H), 9.70 (s, 1H),
8.01 (t, J＝10.6 Hz, 2H), 7.49 (dd, J＝15.4, 7.2 Hz, 7H),
7.32 (t, J＝7.7 Hz, 2H), 7.16 (d, J＝8.0 Hz, 2H), 7.08 (t,
J＝7.3 Hz, 1H), 6.93 (s, 1H), 4.16 (s, 2H), 2.26 (s, 3H);
13C NMR (100 MHz, DMSO-d6) δ: 171.6, 169.6, 161.6,
161.2, 151.1, 138.0, 137.2, 136.9, 132.3, 130.9, 129.7,
129.3, 126.9, 124.1, 120.7, 120.0, 98.6, 35.7, 20.9.
2-((4-((4-Chlorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5h) Yield 90.6%, white solid, m.p. 213－214
1
℃; H NMR (400 MHz, DMSO-d6) δ: 11.34 (s, 1H),
HR-MS (ESI) calcd for C26H23N5O2S [M ＋ H] ＋
:
10.83 (s, 1H), 10.19 (s, 1H), 8.30 (d, J＝4.6 Hz, 1H),
8.00 (d, J＝5.9 Hz, 3H), 7.89 (t, J＝7.2 Hz, 1H), 7.72 (d,
J＝8.8 Hz, 2H), 7.54－7.44 (m, 3H), 7.40 (d, J＝8.7 Hz,
2H), 7.22－7.11 (m, 1H), 7.06 (s, 1H), 4.23 (s, 2H); 13C
NMR (100 MHz, DMSO-d6) δ: 171.3, 169.3, 160.9,
150.8, 150.1, 146.1, 141.4, 138.8, 136.2, 131.2, 129.3,
129.1, 127.0, 126.8, 121.9, 120.3, 114.7, 99.6, 36.0.
HR-MS (ESI) calcd for C24H19ClN6O2S [M＋H]＋ :
491.1057, found 491.1055.
470.1651, found 470.1649.
2-((4-((4-Fluorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(phenylcarbamoyl)acetamide (6b)
1
Yield 81.9%, white solid, m.p. 198－199 ℃; H NMR
(400 MHz, DMSO-d6) δ: 11.06 (s, 1H), 10.38 (s, 1H),
9.82 (s, 1H), 8.00 (d, J＝6.3 Hz, 2H), 7.71－7.60 (m,
2H), 7.50 (dd, J＝11.8, 7.4 Hz, 5H), 7.32 (t, J＝7.6 Hz,
2H), 7.20 (t, J＝8.7 Hz, 2H), 7.08 (t, J＝7.4 Hz, 1H),
6.93 (s, 1H), 4.17 (s, 2H); 13C NMR (100 MHz,
DMSO-d6) δ: 172.5, 171.5, 161.7, 161.1, 151.1, 137.9,
136.8, 136.2, 131.0, 129.3, 126.9, 124.1, 122.2, 120.1,
116.3, 116.1, 115.9, 98.7, 35.7. HR-MS (ESI) calcd for
C25H20FN5O2S [M＋H]＋: 474.1400, found 474.1405.
2-((4-((4-Chlorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(phenylcarbamoyl)acetamide (6c)
2-((4-((2-Chlorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5i) Yield 81.7%, white solid, m.p. 195－196
1
℃; H NMR (400 MHz, DMSO-d6) δ: 11.34 (s, 1H),
10.83 (s, 1H), 10.19 (s, 1H), 8.30 (d, J＝4.6 Hz, 1H),
8.00 (d, J＝5.9 Hz, 3H), 7.89 (t, J＝7.2 Hz, 1H), 7.72 (d,
J＝8.8 Hz, 2H), 7.54－7.44 (m, 3H), 7.40 (d, J＝8.7 Hz,
2H), 7.22－7.11 (m, 1H), 7.06 (s, 1H), 4.23 (s, 2H); 13C
NMR (100 MHz, DMSO-d6) δ: 171.3, 169.3, 160.9,
150.8, 150.1, 146.1, 141.4, 138.8, 136.2, 131.2, 129.3,
129.1, 127.0, 126.8, 121.9, 120.3, 114.7, 99.6, 36.0.
HR-MS (ESI) calcd for C24H19ClN6O2S [M＋H]＋ :
491.1057, found 491.1053.
1
Yield 87.1%, white solid, m.p. 230－231 ℃; H NMR
(400 MHz, DMSO-d6) δ: 11.08 (s, 1H), 10.38 (s, 1H),
9.98 (s, 1H), 8.11－7.95 (m, 2H), 7.70 (d, J＝8.7 Hz,
2H), 7.50 (dd, J＝10.0, 7.9 Hz, 5H), 7.41 (d, J＝8.8 Hz,
2H), 7.31 (t, J＝7.8 Hz, 2H), 7.07 (t, J＝7.3 Hz, 1H),
6.99 (s, 1H), 4.19 (s, 2H); 13C NMR (100 MHz,
DMSO-d6) δ: 171.4, 169.6, 161.6, 160.9, 151.1, 138.9,
138.0, 136.6, 131.1, 129.6, 128.9, 127.0, 126.7, 124.1,
121.7, 120.1, 99.3, 35.8. HR-MS (ESI) calcd for
C25H20ClN5O2S [M＋H]＋: 490.1104, found 490.1106.
2-((4-((3-Chlorophenyl)amino)-6-phenylpyri-
midin-2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acet-
amide (5j) Yield 86.1%, white solid, m.p. 231－232
1
℃; H NMR (400 MHz, DMSO-d6) δ: 11.28 (s, 1H),
10.76 (s, 1H), 10.00 (s, 1H), 8.27 (d, J＝4.1 Hz, 1H),
8.02 (d, J＝7.3 Hz, 2H), 7.98 (s, 1H), 7.89－7.78 (m,
2H), 7.61 (d, J＝8.0 Hz, 1H), 7.52－7.42 (m, 3H), 7.38
(t, J＝8.1 Hz, 1H), 7.11 (dd, J＝12.2, 7.2 Hz, 2H), 7.00
(s, 1H), 4.22 (s, 2H); 13C NMR (100 MHz, DMSO-d6) δ:
171.7, 169.6, 162.0, 161.0, 151.3, 150.9, 148.62, 141.5,
139.0, 136.7, 133.6, 131.1, 130.9, 129.3, 127.0, 122.6,
120.1, 119.6, 118.6, 113.5, 99.5, 35.8. HR-MS (ESI)
calcd for C24H19ClN6O2S [M＋H]＋: 491.1057, found
491.1056.
Results and Discussion
Compounds 3a－3b, 4a－4b, 5a－5k and 6a－6c
were investigated for their in vitro anti-tumor activities
against three human cancer cell lines including MCF-7
(human breast cancer cell line), MGC-803 (human gas-
tric cancer cell line) and EC-109 (human esophageal
cancer cell line) using MTT assay method according to
Mosmann’s method.[15] Table 1 reported the IC50
(μmol•L−1) values (concentration required to achieve
50% inhibition of the tumor growth) of the tested com-
pounds and the standard. It has been observed that
compounds 4a, 4b and 6a showed most effective activ-
ity as compared to other compounds. One of the most
active compounds was 6a, with IC50 values against the
three tested human cancer cell lines ranging from 1.80
to 2.72 μmol•L−1, which was more cytotoxic than
5-fluorouracil.
2-((4-((4-Nitrophenyl)amino)-6-phenylpyrimidin-
2-yl)thio)-N-(pyridin-2-ylcarbamoyl)acetamide (5k)
Yield 92.3%, yellow solid, m.p. 198－199 ℃; 1H NMR
(400 MHz, DMSO-d6) δ: 11.35 (s, 1H), 10.76 (s, 1H),
10.71 (s, 1H), 8.27 (t, J＝6.3 Hz, 3H), 8.03 (dd, J＝7.7,
1.6 Hz, 2H), 7.96 (d, J＝9.2 Hz, 3H), 7.86 (dd, J＝10.8,
4.9 Hz, 1H), 7.49 (dt, J＝8.8, 4.4 Hz, 3H), 7.20 (s, 1H),
13
7.18－7.12 (m, 1H), 4.28 (s, 2H); C NMR (100 MHz,
DMSO-d6) δ: 171.4, 169.8, 162.3, 160.8, 150.8, 150.3,
146.6, 141.6, 140.9, 136.4, 131.3, 129.4, 127.0, 125.5,
120.3, 119.2, 114.4, 100.5, 36.1. HR-MS (ESI) calcd for
C24H19N7O4S [M＋H]＋: 502.1297, found 502.1296.
2-((4-Phenyl-6-(p-tolylamino)pyrimidin-2-yl)thio)-
N-(phenylcarbamoyl)acetamide (6a) Yield 79.7%,
According to the activity data (3a, 4a, and 5a－5k),
it has been observed that the change at 4-position of
-pyrimidine may lead to change in the activity. The
analogues with －Cl and para-substituted anilines were
found to be more effective as compared to compounds
having －OH and ortho- or meta-substituted anilines. It
1
white solid, m.p. 200－201 ℃; H NMR (400 MHz,
446
www.cjc.wiley-vch.de
© 2014 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2014, 32, 443—447

Synthesis and Antitumor Activity Evaluation of Pyrimidine Analogues Bearing Urea Moiety
Table 1 Inhibitory results of pyrimidine derivatives against
phenyl ring influenced the antitumor activities remarka-
three human cancer cell lines
bly. Biological activity data revealed that compounds 4a,
4b and 6a showed most effective activity. Among them,
6a was more cytotoxic than 5-fluorouracil against all
tested three human cancer cell lines, which is under fur-
ther investigation as lead structure. Further modifica-
tions and SAR study are undergoing and will be re-
ported elsewhere.
R
N
H
H
X
N
N
S
N
O
O
IC50a/(μmol•L−1)
MGC-803 MCF-7 EC-109
Compound X
R
Acknowledgments
N
OH-
＞100
＞100
7.63
＞100 64.92
3a
3b
4a
4b
5a
5b
5c
5d
5e
5f
This work was supported by the National Natural
Science Foundation of China (Nos. 81172937,
U1204206), China Postdoctoral Science Foundation
(Nos. 20100480857, 201104402) and New Teachers’
Fund for Doctor Stations, Ministry of Education (No.
20114101120013).
CH OH-
Cl-
CH Cl-
73.20 45.45
N
8.77
3.71
3.03
25.38 11.01
42.34 47.72
23.36 28.21
＞100 64.58
85.36 70.13
22.97 26.81
＞100 ＞100
67.73 89.65
＞100 ＞100
＞100 ＞100
＞100 ＞100
＞100 ＞100
N
N
N
N
N
N
N
N
N
N
N
C6H5-NH-
38.76
15.69
73.16
4-CH3-C6H5-NH-
3-CH3-C6H5-NH-
References
4-butyl-C6H5-NH- 61.82
4-CH3O-C6H5-NH- 10.33
2-CH3O-C6H5-NH- ＞100
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4-F-C6H5-NH-
4-Cl-C6H5-NH-
2-Cl-C6H5-NH-
3-Cl-C6H5-NH-
52.92
65.77
＞100
＞100
5g
5h
5i
5j
4-NO2-C6H5-NH- ＞100
5k
6a
6b
6c
5-Fu
CH 4-CH3-C6H5-NH-
CH 4-F-C6H5-NH-
CH 4-Cl-C6H5-NH-
2.19
1.80
2.72
38.79
54.21
3.80
10.54 42.38
32.28 68.43
6.45
5.15
a Inhibitory activity was assayed by exposure for 72 h to sub-
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is worthy to mention that electron donating groups
(－CH3, －CH2CH2CH2CH3 and －OCH3) on benzene
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groups (－F, －Cl, －NO2). Moreover, reviewing and
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4b, 6a－6c), it is worthy to mention that the benzene
ring is more effective than the pyridine ring.
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Conclusions
In conclusion, we synthesized a series of pyrimidine
hybrids containing urea moiety and their antitumor ac-
tivities were evaluated in vitro against three human
cancer cell lines. The nature of the aromatic ring at-
tached directly to urea and the substitutions on the
(Cheng, F.)
Chin. J. Chem. 2014, 32, 443—447
© 2014 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
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