Synthesis of new diarylamides with pyrimidinyl pyridine scaffold and evaluation of their anti-proliferative effect on cancer cell lines

Article abstract of DOI:10.1016/j.bmcl.2016.01.014

A new series of diarylamides, having a pyrimidinyl pyridine scaffold, was designed and synthesized. The target compounds were synthesized in three steps. A selected group from the target compounds was tested over a panel of 60 cancer cell lines at a singl

Full text of DOI:10.1016/j.bmcl.2016.01.014

Bioorganic & Medicinal Chemistry Letters xxx (2016) xxx–xxx
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry Letters
journal homepage: www.elsevier.com/locate/bmcl
Synthesis of new diarylamides with pyrimidinyl pyridine scaffold
and evaluation of their anti-proliferative effect on cancer cell lines
Ahmed Z. Abdelazem a,b,d, , Mohammad M. Al-Sanea a,b,e, Hyun-Mee Park c, So Ha Lee a,b
⇑
a Chemical Kinomics Research Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea
b Department of Biological Chemistry, University of Science and Technology, 113 Gwahangno, Yuseong-gu, Daejeon 305-333, Republic of Korea
c Advanced Analysis Center, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Republic of Korea
d Biotechnology & Life Sciences Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Egypt
e Pharmaceutical Chemistry Department, Faculty of Pharmacy, Modern University for Technology & Information, Cairo, Egypt
a r t i c l e i n f o
a b s t r a c t
Article history:
A new series of diarylamides, having a pyrimidinyl pyridine scaffold, was designed and synthesized. The
target compounds were synthesized in three steps. A selected group from the target compounds was
tested over a panel of 60 cancer cell lines at a single dose concentration of 10 lM, and the most active
compound, 5j, was further tested in a five-dose testing mode to determine its IC50 value over the 60 cell
lines. In single-dose testing mode, compound 5j showed the highest growth inhibition against the NCI-60
cancer cell lines, while other tested compounds showed a weak to moderate inhibitory activity against a
range of different cancer cell lines. In five-dose testing mode, compound 5j showed strong inhibitory
activity in micro molar range against many cancer cell lines. Its major activity was against melanoma
cancer cell lines. Therefore, compound 5j is a promising hit compound targeting this severe form of
cancer.
Received 13 August 2015
Revised 29 December 2015
Accepted 7 January 2016
Available online xxxx
Keywords:
Synthesis
Anti-proliferative effect
Pyrimidinyl pyridine
Diarylamide
Ó 2016 Elsevier Ltd. All rights reserved.
Melanoma
Cancer is a group of diseases characterized by abnormalities in
cellular growth, proliferation, and survival pathways, resulting in
uncontrolled expansion of cancer cells and tumor formation.
Collectively, these diseases represent one of the most pressing
challenging health problems in the 21st century.1 The develop-
ment of cancer is a complex multi-step process in which malignant
cells gradually change as a result of a series of mutations.2 There is
still an urgent need for searching for and developing of more
potential anticancer agents with minimal side effects.
Melanoma is a type of skin cancer which is formed from mela-
nocytes (pigment-containing cells in the skin). Incidence of mela-
noma has tripled in the last 40 years.3 Melanoma is less common
than other skin cancers. However, it is much more dangerous if it
is not found in the early stages. It causes the majority (75%) of
deaths related to skin cancer.4
(FDA) for treatment of chronic myeloid leukemia (CML) with
diminished side effects.14
In a previous study by our group, we used the pyrimidinyl pyr-
idine moiety as a part of the chemical scaffold of some potent
antiproliferative compounds.15 A noteworthy observation is that
the diarylamide and the pyrimidinyl pyridine moieties were com-
bined in the structure of Imatinib.
Encouraged by the interesting antiproliferative activity of the
diarylamide derivatives, and as a continuation of our previous
study about the pyrimidinyl pyridine scaffold,15 we designed and
synthesized a series of new diarylamides containing a pyrimidinyl
pyridine scaffold (Fig. 1). A selected group (8 compounds) from the
target compounds was tested over a panel of 60 cancer cell lines at
a single dose concentration of 10 lM, and the most active com-
pound 5j was further tested in a five-dose testing mode to deter-
Diarylamides have been highlighted as potential antiprolifera-
tive agents against a variety of cancer cell lines.5–13 Imatinib
(GleevecÒ) (Fig. 1) is an example of anticancer diarylamide that
has been approved by the U.S. Food and Drug Administration
mine its IC50 value over the 60 cell lines.
A simple synthetic strategy was used to obtain the target com-
pounds 5a–j as illustrated in Scheme 1.
Treatment of 2-amino-4,6-dichloropyrimidine (1) with the
amine 2a or 2b led to nucleophilic displacement of chloro group
by aliphatic amine group. Two regioisomers resulted from this
step, the major one was the 4-amino substituent, 3a or 3b, as it
was proved using 2D NOESY, and also it coincides with literature
data.16 The pure isomers 3a and 3b were subjected to Suzuki cou-
pling with 3-pyridine boronic acid to give compounds 4a and 4b,
⇑
Corresponding author at: Chemical Kinomics Research Center, Korea Institute of
Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791,
Republic of Korea. Tel.: +82 02 958 6795.
E-mail address: aznagi2003@gmail.com (A.Z. Abdelazem).
http://dx.doi.org/10.1016/j.bmcl.2016.01.014
0960-894X/Ó 2016 Elsevier Ltd. All rights reserved.
Please cite this article in press as: Abdelazem, A. Z.; et al. Bioorg. Med. Chem. Lett. (2016), http://dx.doi.org/10.1016/j.bmcl.2016.01.014

2
A. Z. Abdelazem et al. / Bioorg. Med. Chem. Lett. xxx (2016) xxx–xxx
X
N
H
N
O
N
HN
N
N
H
N
H
N
N
N
O
R
N
N
R = morpholine, methoxy
X = various substitutents
Imatinib
Target Compounds
Figure 1. Structures of Imatinib and target compounds with highlight of the common structural features.
Cl
N
NH2
Cl
N
NH2
HN
N
NH2
R
i
R
NH2
N
+
+
N
N
NH
R
Cl
Cl
2a: R = (CH2)3OCH3
2b
Major isomer
: R = (CH2)3Morpholine
1
3a: R = (CH2)3OCH3
3b
: R = (CH2)3Morpholine
Ar
H
H
HN
N
NH2
N
N
N
R
R
ii
N
N
iii
N
N
O
4a: R = (CH2)3OCH3
5a-j
4b
: R = (CH2)3Morpholine
Scheme 1. Reaction conditions and reagents: (i) n-butanol, TEA, 90 °C, 12 h; (ii) 3-pyridineboronic acid, Pd(PPh3)4, K2CO3, DME/H2O (4:1), 12 h; (iii) ArCOOH, EDCI, THF,
DMAP, 0 °C–rt, 24 h.
respectively. The nucleophilic substitution of the 4-chloro group in
the first step was proved by two pieces of evidences. First, the 2D
NOESY spectrum of compound 3a, as a representative, did not
show any coupling interaction between the secondary amine pro-
ton and the aromatic proton. Second, in the 2D NOESY spectrum of
compound 4a, as a representative, there is cross interaction
between the aromatic proton of the pyrimidine ring and two aro-
matic protons from the pyridine ring (Fig. 2).
In the final step, through amide coupling, compounds 4a and 4b
were coupled to five different substituted benzoic acid derivatives
to give the target compounds 5a–j. Structures of the target com-
pounds are illustrated in Table 1.
Table 1
Structures of the target compounds and mean% inhibition
H
N
H
N
N
Ar
R
N
N
O
5a-j
Compd No.
R
Ar
Mean% inhibition
0.78
The structure of the target compounds were submitted to the
NCI, Bethesda, Maryland, USA, and eight compounds out of ten
were selected on the basis of degree of structural variation and
computer modeling techniques for evaluation of their
O
O
F
5a
F
5b
5c
2.78
Cl
O
O
Cl
O
Not tested
Cl
O
N
NH2
HN
H
N
N
O
H
H
5d
5e
8.06
O
CF3
4a
11.33
Br
Figure 2. 2D-NOESY NMR spectrum of compound 4a.
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A. Z. Abdelazem et al. / Bioorg. Med. Chem. Lett. xxx (2016) xxx–xxx
3
Table 2
Table 1 (continued)
% inhibition of compounds 5a, 5b, 5d, 5e, 5f, 5g and 5i against most sensitive cancer
cell lines
Compd No.
R
Ar
Mean% inhibition
1.46
F
O
Compd
No.
Cell line
Cancer type
% inhibition at
10
l
M
5f
N
N
5a
HOP-92
Non-small cell lung
cancer
32.97
F
O
O
NCI-H522
Non-small cell lung
cancer
21.40
5g
3.57
Cl
5b
5d
A498
UO-31
RPMI-8226
HOP-92
Renal cancer
Renal cancer
Leukemia
Non-small cell lung
cancer
45.92
21.50
30.65
47.41
Cl
O
N
N
5h
5i
Not tested
NCI-H522
Non-small cell lung
cancer
23.53
Cl
O
O
SK-MEL-2
SK-MEL-5
SNB-75
OVCAR-8
UO-31
Melanoma
Melanoma
CNS cancer
Ovarian cancer
Renal cancer
Breast cancer
21.20
27.60
26.88
20.70
43.26
30.87
8.88
O
CF3
MDA-MB-231/
ATCC
N
5j
57.16
T-74D
K-562
RPMI-8226
HOP-92
Breast cancer
Leukemia
Leukemia
Non-small cell lung
cancer
36.18
26.67
34.44
42.06
5e
Br
SK-MEL-5
A498
UO-31
PC-3
MDA-MB-231/
ATCC
Melanoma
29.51
23.77
39.45
29.38
24.20
Renal cancer
Renal cancer
Prostate cancer
Breast cancer
antiproliferative activity. The selected compounds were tested for
their in vitro antiproliferative activity against tumor cells in a full
panel of 60 cell lines taken from nine different tissues (blood, lung,
colon, CNS, skin, ovary, kidney, prostate, and breast).17 The com-
T-74D
NCI-H226
Breast cancer
Non-small cell lung
cancer
Non-small cell lung
cancer
Renal cancer
Leukemia
Leukemia
Non-small cell lung
cancer
Melanoma
Renal cancer
Breast cancer
34.98
22.36
pounds were tested at a single-dose concentration of 10 lM. The
5f
mean inhibition percentages of all of the tested compounds over
the full panel of cell lines are illustrated in Table 1 and the figures
showing the inhibitions exerted by each compound over the full
cell lines panel are showed in the Supplementary data. Compound
5j was the most active against the tested cell lines; its mean% inhi-
bition is far higher than other tested compounds. It showed growth
inhibition value of more than 50% in 19 cancer lines, and lethal
effect in 7 cancer lines (Fig. 3). Compounds 5a, 5b, 5d, 5e, 5f, 5g
and 5i showed weak to moderate growth inhibition against a range
of cancer cell lines (Table 2). Certain cell lines were commonly
sensitive to many of the tested compounds. The cell lines HOP-
92, UO-31, T-47D, SK-MEL5, MDA-MB-231/ATCC and A498 were
sensitive to three or more of the tested compounds. We tried to
find a common genetic mutation in these cell lines in the light of
a research about genetic mutation in NCI cell line set,18 but the
only common genetic mutation was CDKN2A, which is a common
A498
22.81
5g
5i
UO-31
K-562
SR
22.97
25.87
42.09
32.33
NCI-H226
SK-MEL-5
UO-31
MDA-MB-231/
ATCC
31.69
46.44
20.44
T-74D
Breast cancer
27.18
mutation in the majority of NCI-60 cancer cell lines and isn’t speci-
fic to the commonly sensitive cell lines. Therefore, there might be
another common genetic variation, that is, not elaborated yet.
Figure 3. % inhibition expressed by compound 5j at a single-dose concentration of 10 lM over the NCI-60 cancer cell lines.
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4
A. Z. Abdelazem et al. / Bioorg. Med. Chem. Lett. xxx (2016) xxx–xxx
Table 3
In summary, a series of new diarylamides possessing a pyrim-
IC50 values (lM) of compound 5j over the most sensitive cell lines
idinyl pyridine scaffold was synthesized based on the Imatinib
structure and also on our previous literature study. The in vitro
antiproliferative activities were screened over the NCI-60 cancer
cell line panel of nine different cancer types. It was found that
compound 5j with the common central pyrimidinyl pyridine moi-
ety, 3-morpholinopropylamino as polar chain, and 3-bromo-5-(tri-
fluoromethyl)phenyl terminal ring, showed the highest inhibition
percentages with great selectivity toward melanoma cell lines. In
five-dose testing mode, compound 5j showed the highest inhibi-
tory activity against melanoma cell lines. Therefore, due to its high
activity toward melanoma cell lines, compound 5j can be consid-
ered as a promising lead for the development of potent anticancer
agents for treatment of melanoma.
Cancer cell lines
Lung
IC50 (lM)
HOP-92
1.97
1.95
1.77
1.77
1.92
1.94
1.67
1.52
1.62
1.76
1.67
1.66
1.73
1.62
1.94
1.55
1.80
1.40
1.79
NCI-H522
COLO 205
HCC-2998
HCT-15
SF-295
SF-539
Colon
CNS
SNB-75
Melanoma
LOX IMVI
MALME-3M
M14
MDA-MB-435
SK-MEL-28
SK-MEL-5
UACC-62
786-0
Acknowledgements
Renal
RXF 393
UO-31
MDA-MB-231/ATCC
This research was supported by Korea Institute of Science and
Technology (2E24760). We would like to express our gratitude
and thanks to the National Cancer Institute (NCI), Bethesda
Maryland, USA for performing the anticancer testing of new
compounds.
Breast
Compound 5j has the same pyrimidinyl pyridine core moiety as
other compounds in this series. In addition to the common central
moiety, compound 5j has a 3-morpholinopropylamino as polar
chain, and a 3-bromo-5-(trifluoromethyl)phenyl terminal ring. A
notable observation is that the difference between compound 5e
and compound 5j is only in the polar chain, but the activity of com-
pound 5j is far higher than compound 5e. Therefore, it seems that
the compound should be considered as a whole rather than its
individual components.
Supplementary data
Supplementary data associated with this article can be found, in
the online version, at http://dx.doi.org/10.1016/j.bmcl.2016.01.
014.
References and notes
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a
promising hit candidate to develop new effective drugs against
melanoma, this severe form of cancer.
Please cite this article in press as: Abdelazem, A. Z.; et al. Bioorg. Med. Chem. Lett. (2016), http://dx.doi.org/10.1016/j.bmcl.2016.01.014