Synthesis of quinolinylaminopyrimidines and quinazolinylmethylaminopyrimidines with antiproliferative activity against melanoma cell line

Article abstract of DOI:10.3109/14756366.2014.958082

Synthesis of a new series of quinolinylaminopyrimidines 1a-k and quinazolinylmethylaminopyrimidines 2a-i containing aminoquinoline and aminoquinazoline as hinge regions is described. Their in vitro antiproliferative activities against A375P human melanoma cell line were tested. Among them, compounds 1h and 1k exhibited the highest antiproliferative activities against A375P cell line with IC₅₀ values in sub-micromolar scale. Compounds 1i, 2b and 2g showed similar potency against A375P to Sorafenib as a reference compound. The representative compound 1h showed high, dose-dependent inhibition of MEK and ERK kinases.

Full text of DOI:10.3109/14756366.2014.958082

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ISSN: 1475-6366 (print), 1475-6374 (electronic)
J Enzyme Inhib Med Chem, Early Online: 1–8
2014 Informa UK Ltd. DOI: 10.3109/14756366.2014.958082
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RESEARCH ARTICLE
Synthesis of quinolinylaminopyrimidines and
quinazolinylmethylaminopyrimidines with
antiproliferative activity against melanoma cell line
Jun A Lee1,3, Eun Joo Roh1, Chang-Hyun Oh2, So Ha Lee1, Taebo Sim1, Jong Seung Kim3, and Kyung Ho Yoo1
2
1Chemical Kinomics Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul, Republic of Korea, Center for Biomaterials,
3
Korea Institute of Science and Technology, Cheongryang, Seoul, Republic of Korea and Department of Chemistry, Korea University, Seoul,
Republic of Korea
Abstract
Keywords
Synthesis of a new series of quinolinylaminopyrimidines 1a–k and quinazolinylmethylamino-
pyrimidines 2a–i containing aminoquinoline and aminoquinazoline as hinge regions is
described. Their in vitro antiproliferative activities against A375P human melanoma cell line
were tested. Among them, compounds 1h and 1k exhibited the highest antiproliferative
activities against A375P cell line with IC50 values in sub-micromolar scale. Compounds 1i, 2b
and 2g showed similar potency against A375P to Sorafenib as a reference compound. The
representative compound 1h showed high, dose-dependent inhibition of MEK and ERK kinases.
Antiproliferative, MEK/ERK kinase inhibition,
melanoma cell line, quinazoline, quinoline
History
Received 12 June 2014
Revised 19 August 2014
Accepted 19 August 2014
Published online 27 November 2014
Introduction
Vemurafenib (PLX4032, ZelborafÕ, Figure 1) is another drug
which targets ERK pathway through inhibition of V600E-B-RAF
kinase. In 2011, it was approved by the U.S. Food and Drug
Administration (FDA) for treatment of late-stage melanoma10.
So, inhibition of ERK signaling pathway is a very potential
avenue for treatment of melanoma.
Numerous compounds with new scaffolds consisting of hinge,
spacer, and tail regions have recently reported as potential
antiproliferative agents against melanoma cell lines11–22. In this
work, a new series of quinolinylaminopyrimidines 1a–k and
quinazolinylmethylaminopyrimidines 2a–i containing aminoqui-
noline and aminoquinazoline as hinge regions was designed and
synthesized (Figure 1). Their in vitro antiproliferative activities
were tested over A375P human melanoma cell line. And MEK
and ERK kinases inhibitory activity for the representative
compound 1h is reported.
Melanoma is a malignant tumor that arises from melanocytic cells
and primarily involves the skin. Exposure to solar ultraviolet
irradiation, fair skin, dysplastic nevi syndrome, and a family
history of melanoma are major risk factors for melanoma
development. Melanomas can metastasize either by the lymphatic
or by the hematogenous route1. Metastatic melanoma is a
particularly aggressive form of cancer that has a very poor
prognosis, and is resistant to standard anticancer therapies. Early
stage melanoma (stage I/II) can be cured surgically with more
than 95% success rate. But melanoma metastasizing to major
organs (stage IV) is virtually incurable2. Patients with advanced
melanoma have a median survival time of less than one year, and
the estimated five-year survival rate is less than 15%3,4. With the
rapid incidence of melanoma in the United States and other
developed countries, there is an urgent need to develop more
effective drugs5–7. The RAS-RAF-MEK-ERK signaling pathway
(ERK pathway) plays an important role in tumorigenesis and
cancer progression8. Sorafenib (NexavarÕ, Figure 1) targets ERK
pathway. It inhibits basal phosphorylation of ERK (p-ERK) in
numerous cancer cell lines in vitro, including melanoma cell lines,
independent of their K-RAS and b-RAF mutational status9.
Experimental
Chemistry
1H NMR spectra were recorded on a Bruker Avance 400
spectrometer using DMSO-d6 containing tetramethylsilane as an
internal standard. LC-MS spectra were determined on a Waters
Quattro Micro System. The liquid chromatography high-reso-
lution mass spectra (LC-HRMS, electron spray ionization)
experiments were performed with Synapt G2 (Waters MS
Technology, Manchester, Q-TOF MS, UK) mass analyzer. Data
were acquired in the positive ion mode. Calibration was
performed with an external calibration mixture immediately
prior to analysis. Column chromatography was carried out using
silica gel (230–400 mesh). Solvents and liquid reagents were
Address for correspondence: Dr. Kyung Ho Yoo, Chemical Kinomics
Research Center, Korea Institute of Science and Technology, PO Box 131,
Cheongryang, Seoul 130-650, Republic of Korea. Tel: +82-2-958-5152.
Fax: +82-2-958-5189. E-mail: khyoo@kist.re.kr

2
J. Lee et al.
J Enzyme Inhib Med Chem, Early Online: 1–8
F
Figure 1. Structures of Sorafenib,
Vemurafenib, and the target compounds.
Cl
O
H
N
H
O
S
N
N
CF
Cl
O
3
N
H
F
H
N
O
O
N
N
H
O
Vemurafenib
Sorafenib
N
N
N
N
N
H N
R
R
2
N
H
N
N
N
N
N
N
H
H
H
H
2a-i
R = aromatics
1a-k
R = aromatics
transferred using hypodermic syringes. Purity % of all the 2-Methyl-5-(4-(8-nitroquinolin-4-ylamino)pyrimidin-2-ylamino)-
target compounds were determined by LC-MS and found to be benzonitrile (6b)
495%.
Brown solid, yield 15%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
9.51 (s, 1H), 8.85 (d, J ¼ 4.32 Hz, 1H), 8.35–8.32 (m, 2H), 8.15–
4-Chloro-8-nitroquinoline (3)
8.11 (m, 2H), 7.82 (s, 1H), 7.64 (d, J ¼ 9.68 Hz, 1H), 7.22
To a solution of 4-chloroquinoline (2) (5.0 g, 0.031 mmol) in (d, J ¼ 8.64 Hz, 1H), 6.5 (s, 1H), 2.33 (s, 3H).
added dropwise at 0 ꢀC. The mixture was stirred at room 8-Nitroquinolin-4-yl-N2-(4-trifluoromethylphenyl)pyrimidine-2,
temperature for 4 h. Upon completion, the reaction mixture was 4-diamine (6c)
sulfuric acid (23 mL, 0.42 mol), nitric acid (4.5 mL, 0.11 mol) was
cooled to 0 ꢀC and neutralized with 1 M NH4OH. The resulting
1
White solid, yield 20%; H NMR (400 MHz, DMSO-d6, d, ppm):
precipitate was collected by filtration, washed with water, and
9.90 (s, 1H), 9.68 (s, 1H), 8.90 (d, J ¼ 4.82 Hz, 1H), 8.38 (s, 2H),
dried to give the title compound 3 (3.6 g, 56%) as a white solid.
8.23 (d, J ¼ 5.69 Hz, 1H), 7.91 (d, J ¼ 4.77 Hz, 1H), 7.83 (d,
1H NMR (400 MHz, DMSO-d6, d, ppm): 8.93 (d, J ¼ 4.59 Hz,
J ¼ 8.45 Hz, 2H), 7.46 (d, J ¼ 8.44 Hz, 1H), 6.55 (d, J ¼ 5.69 Hz,
1H), 8.47 (d, J ¼ 8.44 Hz, 1H), 8.08 (d, J ¼ 7.33 Hz, 1H), 7.74
1H).
(t, J ¼ 8.02 Hz, 1H), 7.59 (d, J ¼ 6.76 Hz, 1H).
8-Nitroquinolin-4-yl-N2-(3-trifluoromethylphenyl)pyrimidine-2,
General procedure for the synthesis of
4-diamine (6d)
pyrimidin-2,4-diamines 5
1
White solid, yield 15%; H NMR (400 MHz, DMSO-d6, d, ppm):
To a mixture of 2-chloropyrimidin-4-amine (4) (2.0 mmol),
( )-2,2-bis(diphenylphosphino)-1,1’-binaphinyl
8.85 (d, J ¼ 4.66 Hz, 1H), 8.54 (d, J ¼ 9.44 Hz, 1H), 8.32
[( )-BINAP]
(d, J ¼ 9.44 Hz, 1H), 8.26 (d, J ¼ 5.66 Hz, 1H), 7.96 (s, 1H),
7.85 (s, 1H), 7.63 (d, J ¼ 8.63 Hz, 1H), 7.55 (d, J ¼ 4.71 Hz, 1H),
7.41 (t, J ¼ 7.79 Hz, 1H), 7.29 (d, J ¼ 7.47 Hz, 1H), 6.33
(d, J ¼ 5.64 Hz, 1H).
(0.20 mmol), palladium (II) acetate (0.20 mmol), and cesium
carbonate (0.30 mmol) in toluene, the appropriate aminobenzene
(2.1 mmol) was added. The mixture was refluxed under N2
atmosphere for 6 h. Upon completion, the reaction mixture was
filtered through a pad of celite. The filtrate was evaporated under
reduced pressure, and the resulting residue was purified by
column chromatography to afford the corresponding compound 5
(21–60%).
2-Chloro-4-trifluoromethylphenyl-N4-(8-nitroquinolin-4-yl)
pyrimidine-2,4-diamine (6e)
Brown solid, yield 135%; 1H NMR (400 MHz, DMSO-d6, d,
ppm): 8.86 (d, J ¼ 4.82 Hz, 1H), 8.62 (d, J ¼ 8.74 Hz, 1H),
8.45 (d, J ¼ 9.40 Hz, 1H), 8.35 (d, J ¼ 9.40 Hz, 1H), 8.30 (d,
J ¼ 5.60 Hz, 1H), 7.85 (s, 1H), 7.66 (s, 2H), 7.57 (d, J ¼ 4.67 Hz,
1H), 7.44 (d, J ¼ 8.74 Hz, 1H), 6.42 (d, J ¼ 5.60 Hz, 1H).
General procedure for preparation of nitroquinolinyla-
minopyrimidines 6a–k
To a solution of 4-chloro-8-nitroquinoline (3) (0.50 mmol) in
DMF, the appropriate pyrimidin-2,4-diamines 5 (0.55 mmol) and
NaOtBu (0.75 mmol) were added. After stirring at room tempera-
ture for 4 h, the reaction mixture was diluted with saturated
4-Chloro-3-trifluoromethylphenyl-N4-(8-nitroquinolin-4-yl)
pyrimidine-2,4-diamine (6f)
1
aqueous NaHCO3, and extracted with ethyl acetate. The organic White solid, yield 12%; H NMR (400 MHz, DMSO-d6, d, ppm):
layer was washed with brine, dried over anhydrous MgSO4, and 8.85 (d, J ¼ 4.68 Hz, 1H), 8.46 (d, J ¼ 9.44 Hz, 1H), 8.32
concentrated in vacuo. The residue was purified by column (d, J ¼ 9.44 Hz, 1H), 8.26 (d, J ¼ 5.64 Hz, 1H), 8.0 (d,
chromatography to afford the corresponding compounds 6a–k.
J ¼ 2.47 Hz, 1H), 7.82 (s, 1H), 7.63 (d, J ¼ 2.59 Hz, 1H), 7.56
(d, J ¼ 4.72 Hz, 1H), 7.40 (d, J ¼ 8.64 Hz, 1H), 7.16 (s, 1H), 6.34
(d, J ¼ 5.67 Hz, 1H).
3,4-Dimethylphenyl-N4-(8-nitroquinolin-4-yl)pyrimidine-2,4-
diamine (6a)
4-Fluoro-3-trifluoromethylphenyl)-N4-(8-nitroquinolin-4-yl)
pyrimidine-2,4-diamine (6g)
1
White solid, yield 15%; H NMR (400 MHz, DMSO-d6, d, ppm):
8.82 (s, 1H), 8.65 (d, J ¼ 6.19 Hz, 1H), 8.25 (d, J ¼ 7.88 Hz, 1H),
8.20 (s, 1H), 7.85 (s, 1H), 7.52 (s, 1H), 7.28–7.22 (m, 5H), 6.22 Brown solid, yield 13%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
(s, 1H), 2.24 (s, 3H).
8.85 (d, J ¼ 4.75 Hz, 1H), 8.47 (d, J ¼ 9.45 Hz, 1H), 8.30

DOI: 10.3109/14756366.2014.958082
Quinolinylaminopyrimidines and quinazolinylmethylaminopyrimidines
3
(d, J ¼ 9.42 Hz, 1H), 8.24 (d, J ¼ 5.66 Hz, 1H), 7.90–7.88 (2-(4-Trifluoromethylphenylamino)pyrimidin-4-yl)quinoline-4,
(m, 1H), 7.82 (s, 1H), 7.62–7.59 (m, 1H), 7.55 (d, J ¼ 4.74 Hz, 8-diamine (1c)
1H), 7.17–7.12 (m, 2H), 6.32 (d, J ¼ 5.64 Hz, 1H).
1
White solid, yield 75%; H NMR (400 MHz, DMSO-d6, d, ppm):
8.66 (d, J ¼ 4.65 Hz, 1H), 8.03 (d, J ¼ 8.03 Hz, 1H), 7.68 (d,
J ¼ 8.45 Hz, 3H), 7.57 (d, J ¼ 8.87 Hz, 1H), 7.51–7.43 (m, 6H),
6.73 (s, 1H), 6.0 (d, J ¼ 3.24 Hz, 1H), 5.23 (s, 2H); MS m/z: 397
3-Chloro-5-trifluoromethylphenyl-N4-(8-nitroquinolin-4-yl)
pyrimidine-2,4-diamine (6h)
Brown solid, yield 18%; 1H NMR (400 MHz, DMSO-d6, d, ppm): [M+1]+.
8.85 (d, J ¼ 4.77 Hz, 1H), 8.50 (d, J ¼ 9.42 Hz, 1H), 8.40
(d, J ¼ 9.41 Hz, 1H), 8.27 (d, J ¼ 5.62 Hz, 1H), 7.94 (s, 1H), (2-(3-Trifluoromethylphenylamino)pyrimidin-4-yl)quinoline-4,
7.86 (s, 1H), 7.61 (s, 1H), 7.56 (d, J ¼ 4.76 Hz, 1H), 7.29 (s, 1H), 8-diamine (1d)
6.37 (d, J ¼ 5.66 Hz, 1H).
1
White solid, yield 72%; H NMR (400 MHz, DMSO-d6, d, ppm):
8.66 (d, J ¼ 4.42 Hz, 1H), 8.03 (d, J ¼ 4.42 Hz, 1H), 7.94 (s, 1H),
2,4-Bis(trifluoromethyl)phenyl-N4-(8-nitroquinolin-4-yl)
7.70 (d, J ¼ 6.71 Hz, 1H), 7.57 (d, J ¼ 8.82 Hz, 1H), 7.49
pyrimidine-2,4-diamine (6i)
(t, J ¼ 8.84 Hz, 2H), 7.43–7.38 (m, 3H), 7.21 (d, J ¼ 6.72 Hz,
1
White solid, yield 17%; H NMR (400 MHz, DMSO-d6, d, ppm): 1H), 6.74 (s, 1H), 5.97 (d, J ¼ 5.38 Hz, 1H), 5.22 (s, 2H); MS m/z:
8.85 (d, J ¼ 4.76 Hz, 1H), 8.56 (d, J ¼ 8.79 Hz, 1H), 8.40 (d, 397 [M+1]+.
J ¼ 9.42 Hz, 1H), 8.30 (s, 1H), 8.29 (d, J ¼ 2.63 Hz, 1H), 8.03–
7.99 (m, 2H), 7.87 (s, 1H), 7.70 (d, J ¼ 9.17 Hz, 1H), 7.57 (d, (2-(2-Chloro-4-trifluoromethylphenylamino)pyrimidin-4-yl)
J ¼ 4.76 Hz, 1H), 7.46 (s, 1H), 6.46 (d, J ¼ 5.68 Hz, 1H).
quinoline-4,8-diamine (1e)
1
Pale brown solid, yield 59%; H NMR (400 MHz, DMSO-d6, d,
ppm): 8.81 (d, J ¼ 2.76 Hz, 1H), 8.76–8.73 (m, 1H), 8.15–8.10
(m, 2H), 7.64–7.61 (m, 2H), 7.52 (d, J ¼ 4.65 Hz, 1H), 7.44 (q,
3,5-Bis(trifluoromethyl)phenyl-N4-(8-nitroquinolin-4-yl)
pyrimidine-2,4-diamine (6j)
1
White solid, yield 19%; H NMR (400 MHz, DMSO-d6, d, ppm): J ¼ 4.19 Hz, 1H), 7.38 (d, J ¼ 8.58 Hz, 1H), 7.20 (d, J ¼ 8.64 Hz,
8.86 (d, J ¼ 4.76 Hz, 1H), 8.45 (d, J ¼ 9.43 Hz, 1H), 8.34 (d, 1H), 6.54 (s, 1H), 6.05 (d, J ¼ 2.60 Hz, 1H), 5.22 (s, 2H); MS m/z:
J ¼ 9.42 Hz, 1H), 8.30 (d, J ¼ 5.64 Hz, 1H), 8.06 (s, 2H), 7.84 (s, 431 [M+1]+; HRMS (ESI, positive) calcd for C20H15ClF3N6
1H), 7.57 (d, J ¼ 4.76 Hz, 1H), 7.49 (s, 1H), 7.29 (s, 1H), 6.38 [(M+H)+] 431.0921, found 431.0989.
(d, J ¼ 5.64 Hz, 1H).
(2-(4-Chloro-3-trifluoromethylphenylamino)pyrimidin-4-yl)
8-Nitroquinolin-4-yl-N2-(3-phenoxyphenyl)pyrimidine-2,
4-diamine (6k)
quinoline-4,8-diamine (1f)
1
White solid, yield 60%; H NMR (400 MHz, DMSO-d6, d, ppm):
Orange solid, yield 17%; 1H NMR (400 MHz, DMSO-d6, d, ppm): 8.66 (d, J ¼ 4.67 Hz, 1H), 8.05 (d, J ¼ 5.79 Hz, 1H), 8.01 (d,
8.82 (d, J ¼ 4.75 Hz, 1H), 8.62 (d, J ¼ 9.44 Hz, 1H), 8.32 (d, J ¼ 2.58 Hz, 1H), 7.72 (d, J ¼ 2.51 Hz, 1H), 7.57 (d, J ¼ 8.88 Hz,
J ¼ 9.44 Hz, 1H), 8.20 (d, J ¼ 5.60 Hz, 1H), 7.83 (s, 1H), 7.51 (d, 1H), 7.53–7.48 (m, 2H), 7.34 (d, J ¼ 8.86 Hz, 1H), 7.08 (s, 1H),
J ¼ 4.76 Hz, 1H), 7.48 (t, J ¼ 4.24 Hz, 1H), 7.31–7.26 (m, 2H), 6.42 (s, 1H), 5.99 (d, J ¼ 5.73 Hz, 1H), 5.19 (s, 2H); MS m/z: 431
7.22 (d, J ¼ 8.06 Hz, 1H), 7.16 (d, J ¼ 8.31 Hz, 1H), 7.06 (t, [M+1]+; HRMS (ESI, positive) calcd for C20H15ClF3N6
J ¼ 7.35 Hz, 1H), 7.01 (d, J ¼ 7.90 Hz, 1H), 6.65 (d, J ¼ 7.80 Hz, [(M+H)+] 431.0921, found 431.0997.
1H), 6.26 (d, J ¼ 5.60 Hz, 1H).
(2-(4-Fluoro-3-trifluoromethylphenylamino)pyrimidin-4-yl)
General procedure for preparation of
aminoquinolinylaminopyrimidines 1a-k
quinoline-4,8-diamine (1g)
1
Pale brown solid, yield 70%; H NMR (400 MHz, DMSO-d6, d,
A mixture of the appropriate nitroquinolinylaminopyrimidines ppm): 8.66 (d, J ¼ 4.76 Hz, 1H), 8.02 (d, J ¼ 7.88 Hz, 1H), 7.90
6a–k and 5% Pd/C in MeOH was stirred in hydrogen atmosphere (d, J ¼ 8.08 Hz, 1H), 7.75–7.72 (m, 1H), 7.58 (d, J ¼ 11.91 Hz,
at room temperature for 1 h. Upon completion, the reaction 1H), 7.51 (d, J ¼ 6.48 Hz, 2H), 7.14 (s, 1H), 7.09 (t, J ¼ 12.2 Hz,
mixture was filtered through celite. The filtrate was evaporated 1H), 6.58 (s, 1H), 5.98 (d, J ¼ 7.68 Hz, 1H), 5.21 (s, 2H); MS m/z:
under reduced pressure, and the resulting residue was purified by 415 [M+1]+; HRMS (ESI, positive) calcd for C20H15F4N6
column chromatography to afford the corresponding compounds [(M+H)+] 415.1216, found 415.1226.
1a–k.
(2-(3-Chloro-5-trifluoromethylphenylamino)pyrimidin-4-yl)
quinoline-4,8-diamine (1h)
(2-(3,4-Dimethylphenylamino)pyrimidin-4-yl)quinoline-4,
8-diamine (1a)
1
Pale brown solid, yield 50%; H NMR (400 MHz, DMSO-d6, d,
1
White solid, yield 80%; H NMR (400 MHz, DMSO-d6, d, ppm): ppm): 9.64 (s, 1H), 9.01 (s, 1H), 8.68 (d, J ¼ 4.65 Hz, 1H), 8.14
8.82 (s, 1H), 8.66 (s, 1H), 8.26–8.22 (m, 2H), 7.85 (s, 1H), 7.52 (s, (s, 1H), 8.07 (d, J ¼ 5.77 Hz, 1H), 7.85 (s, 1H), 7.71 (s, 1H), 7.69
1H), 7.29–7.22 (m, 5H), 6.22 (s, 1H), 2.22 (s, 6H); MS m/z: 357 (t, J ¼ 2.47 Hz, 1H), 7.41 (d, J ¼ 8.94 Hz, 1H), 7.13 (s, 1H), 6.30
[M+1]+.
(d, J ¼ 5.81 Hz, 1H), 5.83 (s, 2H); MS m/z: 421 [M+1]+.
5-(4-(8-Aminoquinolin-4-ylamino)pyrimidin-2-ylamino)-
2-methylbenzonitrile (1b)
(2-(2,4-Bis(trifluoromethyl)phenylamino)pyrimidin-4-yl)
quinoline-4,8-diamine (1i)
1
Brown solid, yield 56%; 1H NMR (400 MHz, DMSO-d6, d, ppm): Pale brown solid, yield 48%; H NMR (400 MHz, DMSO-d6, d,
8.59 (d, J ¼ 4.64 Hz, 1H), 8.04 (s, 1H), 8.02 (s, 1H), 7.90 (d, ppm): 8.81 (d, J ¼ 1.64 Hz, 1H), 8.80 (d, J ¼ 8.78 Hz, 1H), 8.12
J ¼ 5.88 Hz, 1H), 7.52 (d, J ¼ 8.93 Hz, 1H), 7.45–7.38 (m, 4H), (d, J ¼ 8.28 Hz, 1H), 8.06 (d, J ¼ 5.84 Hz, 1H), 7.82 (s, 1H), 7.61
7.08 (d, J ¼ 8.48 Hz, 1H), 6.76 (s, 1H), 5.88 (d, J ¼ 5.84 Hz, 1H), (d, J ¼ 7.09 Hz, 1H), 7.47–7,42 (m, 2H), 7.36 (d, J ¼ 8.62 Hz,
4.26 (s, 1H), 2.33 (s, 3H); MS m/z: 368 [M+1]+.
1H), 7.20 (d, J ¼ 8.57 Hz, 1H), 6.56 (s, 1H), 6.03 (d, J ¼ 5.72 Hz,

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J. Lee et al.
J Enzyme Inhib Med Chem, Early Online: 1–8
1H), 5.26 (s, 2H); MS m/z: 465 [M+1]+; HRMS (ESI, positive) 1.8 mL, 23.4 mmol) was added. The mixture was stirred at room
calcd for C21H15F6N6 [(M+H)+] 465.1184, found 415.0611.
temperature for 12 h. The solvent was removed by distillation
under reduced pressure, the residue was extracted with CH2Cl2.
The organic layer was washed with brine, dried over anhydrous
Na2SO4, and concentrated in vacuo. The residue was purified by
column chromatography to afford the title compound 11 (1.3 g,
(2-(3,5-Bis(trifluoromethyl)phenylamino)pyrimidin-4-yl)
quinoline-4,8-diamine (1j)
1
White solid, yield 70%; H NMR (400 MHz, DMSO-d6, d, ppm):
1
68%) as a yellow solid. H NMR (400 MHz, DMSO-d6, d, ppm):
8.76 (d, J ¼ 1.64 Hz, 1H), 8.06 (d, J ¼ 1.61 Hz, 1H), 7.37 (t,
J ¼ 4.27 Hz, 1H), 7.32 (d, J ¼ 7.63 Hz, 1H), 7.15 (d, J ¼ 8.10 Hz,
1H), 6.93 (d, J ¼ 1.02 Hz, 1H), 5.0 (s, 2H); MS m/z: 465 [M+1]+;
HRMS (ESI, positive) calcd for C21H15F6N6 [(M+H)+] 465.1184,
found 415.0611.
8.56 (s, 1H), 8.40 (d, J ¼ 4.18 Hz, 1H), 8.18 (d, J ¼ 1.12 Hz, 1H),
7.90 (d, J ¼ 6.28 Hz, 1H), 7.50 (t, J ¼ 7.42 Hz, 1H), 5.18 (s, 2H),
3.01 (d, J ¼ 4.54 Hz, 3H).
General procedure for preparation of quinazolinyl-
methylaminopyrimidines 2a–i
(2-(3-Phenoxyphenylamino)pyrimidin-4-yl)quinoline-4,
8-diamine (1k)
To a solution of 8-bromomethyl-N-methylquinazolin-4-amine
(11) (0.50 mmol) in DMF, the appropriate pyrimidin-2,4-diamines
5 (0.55 mmol) and NaOtBu (0.75 mmol) were added. After
stirring at room temperature for 4 h, the reaction mixture was
diluted with saturated aqueous NaHCO3, and extracted with ethyl
acetate. The organic layer was washed with brine, dried over
anhydrous MgSO4, and concentrated in vacuo. The residue was
purified by column chromatography to afford the corresponding
compounds 2a–i.
Brown solid, yield 60%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.62 (d, J ¼ 4.58 Hz, 1H), 7.99 (d, J ¼ 5.66 Hz, 1H), 7.55 (d,
J ¼ 9.11 Hz, 2H), 7.46 (t, J ¼ 4.66 Hz, 2H), 7.34 (t, J ¼ 7.56 Hz,
4H), 7.21–7.16 (m, 2H), 7.10 (t, J ¼ 7.21 Hz, 2H), 7.05 (d,
J ¼ 8.06 Hz, 2H), 6.61 (d, J ¼ 7.38 Hz, 2H), 5.88 (d, J ¼ 5.60 Hz,
1H), 5.20 (s, 2H); MS m/z: 421 [M+1]+.
8-Methyl-4-quinazolinone (8)
A
mixture of 2-amino-3-methylbenzoic acid (7) (25.0 g,
0.165 mol), formamidine acetate (50.0 g, 0.496 mol), and for-
mamide (6.6 mL, 0.165 mol) was heated at 160 ꢀC for 2 h. Upon
completion, the reaction mixture was cooled to room temperature
and treated with 10% NaOH. After stirring at 60 ꢀC for 20 min,
the reaction mixture was neutralized with 1 N HCl at ice bath
temperature. The resulting precipitate was collected by filtration,
washed with water, and dried to give the title compound 8 (25.4 g,
2-Methyl-5-(4-(4-methylaminoquinazolin-8-yl)methylaminopyri-
midin-2-ylamino)benzonitrile (2a)
Brown solid, yield 15%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.64 (s, 1H), 8.01(s, 1H), 7.93 (d, J ¼ 5.68 Hz, 1H), 7.63 (d,
J ¼ 2.27 Hz, 1H), 7.59 (d, J ¼ 7.24 Hz, 1H), 7.54 (d, J ¼ 8.17 Hz,
1H), 7.49 (d, J ¼ 8.37 Hz, 1H), 7.30 (t, J ¼ 7.52 Hz, 1H), 7.18 (d,
J ¼ 8.41 Hz, 1H), 6.25 (s, 1H), 5.89 (d, J ¼ 5.66 Hz, 1H), 5.73 (s,
1H), 4.78 (s, 2H), 3.15 (s, 3H); MS m/z: 397 [M+1]+; HRMS
(ESI, positive) calcd for C22H21N8 [(M+H)+] 397.1811, found
397.1877.
1
96%) as a white solid. H NMR (400 MHz, DMSO-d6, d, ppm):
12.16 (s, 1H), 8.50 (s, 1H), 7.94 (d, J ¼ 7.94 Hz, 1H), 7.66 (d,
J ¼ 7.38 Hz, 1H), 7.38 (t, J ¼ 7.63 Hz, 1H), 2.51 (s, 3H).
8-Bromomethyl-4-quinazolinone (9)
To a solution of 8-methyl-4-quinazolinone (8) (5.0 g, 31.2 mmol)
in CCl4 (150 mL), N-bromosuccinimide (6 g, 34.3 mmol) and
AIBN (1.0 g, 6.3 mmol) were added. The mixture was stirred at
room temperature for 24 h. Upon completion, the reaction mixture
was filtered through a pad of celite. The filtrate was evaporated
under reduced pressure, and the resulting residue was triturated
with dichloromethane to afford the title compound 9 (5.5 g, 74%)
2-Chloro-5-trifluoromethylphenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2b)
Brown solid, yield 14%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.68(s, 1H), 8.12 (s, 1H), 7.87 (s, 1H), 7.59 (s, 1H), 7.49 (d,
J ¼ 6.0 Hz, 1H), 7.34 (m, 2H), 7.18 (d, J ¼ 8.40 Hz, 1H), 6.01 (s,
1H), 5.61 (s, 2H), 5.30 (d, J ¼ 8.0 Hz, 1H), 3.16 (s, 3H); MS m/z:
460 [M+1]+; HRMS (ESI, positive) calcd for C21H18ClF3N7
[(M+H)+] 460.1186, found 460.1264.
1
as a pale yellow solid. H NMR (400 MHz, DMSO-d6, d, ppm):
12.42 (s, 1H), 8.23 (s, 1H), 8.10 (d, J ¼ 7.86 Hz, 1H), 7.96
(d, J ¼ 6.45 Hz, 1H), 7.50 (t, J ¼ 7.65 Hz, 1H), 5.06 (s, 2H).
3-Chloro-4-trifluoromethylphenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2c)
8-Bromomethyl-4-chloroquinazoline (10)
1
To a solution of 8-bromomethyl-4-quinazolinone (9) (3.0 g,
12.5 mmol) in toluene (100 mL), POCl3 (2.92 mL, 31.3 mmol)
and N,N-dimethylaniline (2.38 mL, 18.8 mmol) were added. The
mixture was refluxed for 4 h and then cooled to room temperature.
The excess of POCl3 was removed by distillation under reduced
pressure. H2O was carefully added to the residue, and the
suspension was extracted with CH2Cl2. The organic layer was
washed with brine, dried over anhydrous Na2SO4, and concen-
trated in vacuo. The residue was purified by column chromatog-
raphy to afford the title compound 10 (2.7 g, 84%) as a white
solid. 1H NMR (400 MHz, DMSO-d6, d, ppm): 9.12(s, 1H),
8.29(d, J ¼ 8.4 Hz, 1H), 8.13(d, J ¼ 7.1 Hz, 1H), 7.76(t,
J ¼ 8.0 Hz, 1H), 5.26(s, 2H).
White solid, yield 14%; H NMR (400 MHz, DMSO-d6, d, ppm):
8.69 (s, 1H), 7.96 (d, J ¼ 5.6 Hz, 1H), 7.78 (d, J ¼ 2.5 Hz, 1H),
7.62 (d, J ¼ 6.9 Hz, 1H), 7.53 (d, J ¼ 8.1 Hz, 1H), 7.46 (dd,
J ¼ 2.5 Hz, 1H), 7.36 (d, J ¼ 2.5 Hz, 1H), 7.34 (d, J ¼ 3.5 Hz, 1H),
5.92 (d, J ¼ 5.7 Hz, 1H), 5.79 (s, 2H), 4.63 (s, 2H), 3.20 (d,
J ¼ 5.5 Hz, 3H); MS m/z: 460 [M+1]+.
4-Fluoro-3-trifluoromethylphenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2d)
Brown solid, yield 13%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.63 (s, 1H), 7.92 (d, J ¼ 5.68 Hz, 1H), 7.63 (m, 2H), 7.50 (m,
1H), 7.46 (d, J ¼ 8.21 Hz, 1H), 7.28 (t, J ¼ 7.42 Hz, 1H), 7.06 (d,
J ¼ 9.44 Hz, 1H), 6.15 (s, 1H), 5.88 (d, J ¼ 5.71 Hz, 1H), 5.72 (s,
1H), 4.75 (s, 2H), 3.15 (s, 3H); MS m/z: 444 [M+1]+; HRMS
(ESI, positive) Calcd for C21H18F4N7 [(M+H)+] 444.1482, found
444.1551.
8-Bromomethyl-N-methylquinazolin-4-amine (11)
To a solution of 8-bromomethyl-4-chloroquinazoline (10) (2.0 g,
7.8 mmol) in THF (50 mL), methylamine (40% solution in water,

DOI: 10.3109/14756366.2014.958082
Quinolinylaminopyrimidines and quinazolinylmethylaminopyrimidines
5
4-(4-(4-Methylaminoquinazolin-8-yl)methylaminopyrimidin-2-
ylamino)-3-trifluoromethylbenzonitrile (2e)
was assessed by the conventional 3-(4,5-dimethylthiazol-2-yl)-
2,5-diphenyltetrazolium bromide (MTT) reduction assay. MTT
assays were carried out with CellTiter 96Õ (Promega) according
to the manufacturer’s instructions. The absorbance at 590 nm was
recorded using EnVision 2103 (Perkin Elmer; Boston, MA). The
IC50 was calculated using GraphPad Prism 4.0 software.
Brown solid, yield 14%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.71 (d, J ¼ 5.84 Hz, 1H), 8.19 (d, J ¼ 9.68 Hz, 1H), 8.10 (d,
J ¼ 8.68 Hz, 1H), 7.89 (t, J ¼ 9.16 Hz, 1H), 7.84 (s, 1H), 7.62 (m,
1H), 7.51 (d, J ¼ 2.64 Hz, 1H), 7.46 (s, 1H), 7.42 (d, J ¼ 3.04 Hz,
1H), 7.38 (d, J ¼ 10.6 Hz, 1H), 5.62 (s, 2H), 7.51 (d, J ¼ 9.72 Hz,
1H), 3.21 (s, 1H); MS m/z: 451 [M+1]+; HRMS (ESI, positive)
calcd for C22H18F3N8 [(M+H)+] 451.1528, found 451.1608.
Kinase Screening
Immunoblot analysis
For immunoblotting, A375P melanoma cells grown to 70–80%
confluence were harvested in RIPA lysis buffer and disrupted by
sonication and centrifuged at 12 000 rpm for 15 min. The quantity
(4-Methylaminoquinazolin-8-yl)methyl-N2-(3-nitro-4-trifluoro-
methylphenyl)pyrimidine-2,4-diamine (2f)
Brown solid, yield 13%; 1H NMR (400 MHz, DMSO-d6, d, ppm): of protein was determined with DC protein assay kit (Bio-Rad
8.73 (s, 1H), 8.07 (s, 1H), 8.03 (d, J ¼ 5.2 Hz, 1H), 7.83 (d, Lab., Hercules, CA). Protein samples were subjected to SDS-
J ¼ 8.9 Hz, 1H), 7.56 (d, J ¼ 8.7 Hz, 2H), 7.53 (d, J ¼ 7.3 Hz, 1H), PAGE and immunoblotted with the appropriate primary anti-
7.32 (t, J ¼ 7.8 Hz, 1H), 6.05 (d, J ¼ 5.6 Hz, 1H), 5.94 (s, 1H), body overnight at 4 ꢀC. The protein bands were visualized
5.84 (s, 1H), 4.77 (s, 2H), 3.22 (d, J ¼ 4.68 Hz, 1H); MS m/z: 471 using chemiluminescence detection kit (Amersham HRP
[M+1]+; HRMS (ESI, positive) calcd for C21H18F3N8O2 Chemiluminescent
Substrates,
Amersham
Biosciences,
[(M+H)+] 471.1427, found 471.1503.
Piscataway, NJ) after hybridization with the HRP-conjugated
secondary antibody from rabbits or mice. The LAS4000-mini
(Fujifilm, Tokyo, Japan) was used for chemiluminescence
detection.
3-Chloro-5-trifluoromethylphenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2g)
Brown solid, yield 12%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.62 (s, 1H), 7.91 (d, J ¼ 5.7 Hz, 1H), 7.58 (d, J ¼ 7.70 Hz, 2H),
7.54 (d, J ¼ 7.12 Hz, 1H), 7.43 (d, J ¼ 8.02 Hz, 1H), 7.27 (s, 1H),
7.16 (t J ¼ 8.85, 1H), 6.51 (d, J ¼ 4.6 Hz, 1H), 5.88 (d,
J ¼ 5.71 Hz, 1H), 5.75 (s, 2H), 4.92 (s, 2H), 3.05 (s, 3H); MS
m/z: 460 [M+1]+; HRMS (ESI, positive) Calcd for C21H18ClF3N7
[(M+H)+] 460.1186, found 460.1255.
Compound treatment in A375P cells
To assess the effect of the target compounds on the RAF-1/MEK/
ERK signaling pathway, A375P cells were treated with the tested
compounds and Sorafenib in a dose dependent way (1, 3, and
10 mM) for 24 h and immunoblotted with antibodies against
phospho-MEK1/2, ERK1/2 and b-actin, respectively.
Results and discussion
2,4-Bis(trifluoromethyl)phenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2h)
Chemistry
Brown solid, yield 16%; 1H NMR (400 MHz, DMSO-d6, d, ppm):
8.73 (s, 1H), 8.07 (s, 1H), 8.03 (d, J ¼ 5.2 Hz, 1H), 7.83 (d,
J ¼ 8.9 Hz, 1H), 7.56 (d, J ¼ 8.7 Hz, 2H), 7.53 (d, J ¼ 7.3 Hz, 1H),
7.32 (t, J ¼ 7.8 Hz, 1H), 6.05 (d, J ¼ 5.6 Hz, 1H), 5.94 (s, 1H),
5.84 (s, 1H), 4.77 (s, 2H), 3.22 (d, J ¼ 4.68 Hz, 1H); MS m/z: 494
[M+1]+.
Quinolinylaminopyrimidines 1a–k were synthesized by the path-
ways illustrated in Scheme 1. Nitration of 4-chloroquinoline (2)
using a mixture of nitric acid and sulfuric acid yielded 4-chloro-8-
nitroquinoline (3). Nucleophilic substitution of the chloro group
of compound 3 with the appropriate pyrimidinyl amines 5
was carried out using sodium t-butoxide to produce compounds
6a–k. Pyrimidinyl amines 5 were obtained by treatment of 2-
chloropyrimidin-4-amine (4) with various aromatic amines in the
presence of ( )-2,20-bis(diphenylphosphino)-1,10-binaphthyl [( )-
BINAP], palladium (II) acetate, and cesium carbonate according
to the procedure of Buchwald-Hartwig amination23. Reduction of
the nitro group of 6a–k using Pd/C in hydrogen atmosphere gave
the title compounds 1a–k.
Synthesis of quinazolinylmethylaminopyrimidines 2a–i was
carried out by the sequence of reactions shown in Scheme 2. Ring
closure of 2-amino-3-methylbenzoic acid (7) with formamidine
acetate in formamide24 followed by bromination with
N-bromosuccinimide in the presence of AIBN gave the bromo-
methylquinazolinone 9 in good yield. Compound 11 as a key
intermediate was obtained by treatment of 9 with phosphoryl
chloride in the presence of N,N-dimethylaniline, and subsequent
amination of the resulting chloroquinazoline 10 using methyla-
mine. Coupling of 11 with the appropriate pyrimidinyl amines 5
by the similar procedure as described for the preparation of 6a–k
led to the title compounds 2a–i.
2,4-Bis(trifluoromethyl)phenyl-N4-(4-methylaminoquinazolin-
8-yl)methylpyrimidine-2,4-diamine (2i)
1
White solid, yield 15%; H NMR (400 MHz, DMSO-d6, d, ppm):
7.98 (d, J ¼ 5.66 Hz, 1H), 7.87 (s, 2H), 7.63 (d, J ¼ 7.2 Hz, 1H),
7.54 (m, 2H), 7.36 (t, J ¼ 7.6 Hz, 1H), 5.96 (t, J ¼ 5.6 Hz, 1H),
5.86 (s, 1H), 5.75 (s, 2H), 3.2 (d, J ¼ Hz, 3H); MS m/z: 494
[M+1]+.
Evaluation of the antiproliferative activity against A375P
human melanoma cell line
A375P cells were purchased from American Type Culture
Collection (ATCC, Rockville, MD) and maintained in
Dulbecco’s modified eagle medium (DMEM, Welgene, Daegu,
Korea) supplemented with 10% fetal bovine serum (FBS,
Welgene, Daegu, Korea) and 1% penicillin/streptomycin
(Welgene, Daegu, Korea) in a humidified atmosphere with 5%
CO2 at 37 ꢀC. A375P cells were taken from culture substrate
with 0.05% trypsin–0.02% EDTA and plated at a density of
5 ꢁ 103 cells/well in 96 well plates and then incubated at 37 ꢀC
Biological activity
for 24 h in a humidified atmosphere with 5% CO2 prior to The antiproliferative activity of the newly synthesized compounds
treatment with various concentrations (3-fold serial dilution, against A375P human melanoma cell line was tested. The ability
12 points) of test compounds. The cells were incubated for 48 h of quinolinylaminopyrimidines 1a–k and quinazolinylmethylami-
after treatment with the test compounds. The A357P cell viability nopyrimidines 2a–i to inhibit the growth of A375P cell line is

6
J. Lee et al.
J Enzyme Inhib Med Chem, Early Online: 1–8
Table 1. Antiproliferative activity of quinolinylaminopyrimidines 1a–k Table 2. Antiproliferative activity of quinazolinylmethylamino
against A375P human melanoma cell line.
pyrimidines 2a–i against A375P human melanoma cell line.
N
N
N
N
N
H N
2
R
R
N
H
N
H
N
N
H
N
H
N
N
H
1a-k
2a-i
Compd.
No.
Compd.
No.
Compd.
No.
Compd.
No.
R
IC50 (mM)
R
IC50 (mM)
420
R
IC50 (mM)
R
IC50 (mM)
1a
6.5
1g
2a
19.3
2f
8.5
CF
3
CN
CF
CN
Cl
1b
15.3
14.0
1h
0.57
3.3
CF
CF
3
2b
2c
4.8
2g
2h
5.8
Cl
F
3
CF
CF
3
3
1c
1i
1j
Cl
3
10.2
10.6
CN
CF
3
CF
3
Cl
NO
2
CF
3
1d
9.3
420
9.2
10.6
0.94
F
CF
3
2d
9.4
8.8
3.4
2i
12.0
CF
CF
3
3
CF
3
CI
Cl
CF
3
1e
1k
CF
CF
3
3
2e
CF
3
CF
CF
3
3
CF
3
1f
Sorafenib
Vemurafenib
0.25
O
Sorafenib
3.4 Vemurafenib
0.25
Sorafenib (μM)
1h (μM)
−
1
3
10
−
1
3
10
summarized in Tables 1 and 2. Sorafenib was selected as a
reference standard because it has been extensively used in clinical
trials for treatment of melanoma5,25. Vemurafenib was also
utilized as a second reference standard in this experiment because
of its high potency against melanoma cell lines26, and it has been
recently approved by the FDA for treatment of advanced
melanoma10.
p-MEK 1/2
p-ERK 1/2
β-actin
Figure 2. Western blot analyses of p-MEK 1/2 and p-ERK 1/2 expression
in presence of compound 1h and Sorafenib.
In general, compounds 1a–k with quinolinylamino moiety
were more potent than compounds 2a-i having quinazolinyl-
methylamino moiety. This may be attributed to that the spacer
length may geometrically permit appropriate fitting of the
molecule at the receptor site. As shown in Table 1, compounds
1h and 1k with sub-micromolar IC50 values displayed superior
antiproliferative activity against A375P human melanoma cell
line to Sorafenib, even though their potencies were less than that
of Vemurafenib. In addition, compound 1i showed higher potency
than Sorafenib. Among all the target compounds, compound 1h
possessing 3-chloro-5-trifluoromethylphenyl as a terminal group
exhibited the highest potency against A375P cell line with IC50
value of 0.57 mM. Compound 1h with 3,5-disubstituted phenyl
group was more potent than compounds 1e and 1f having the
different position of substituents. This may be rationalized that the
orientation of substituents at receptor site may affect the affinity
and potency. As a whole, the structure–activity relationships did
not show a well-defined trend. In quinazolinylmethylaminopyr-
imidine series, compounds 2b and 2g showed similar antiproli-
ferative activities to Sorafenib (Table 2). In order to study the
mechanism of action, compound 1h with high potency against
A375P human melanoma cell line was selected as a representative
example of this series to be screened for its inhibitory effects on
MEK and ERK kinases (Figure 2). A375P cell lysate was treated
with three different concentrations of the test compound (1, 3, and
10 mM), and its inhibitory activity was compared with that of
Sorafenib. The results showed that compound 1h and Sorafenib
markedly suppressed phosphorylation of MEK1/2 and ERK1/2 in
a dose-dependent manner. Compound 1h inhibited ERK kinase
more than MEK kinase at the same concentrations. Therefore, it
can be concluded that this compound may inhibit melanoma cell
proliferation through ERK kinase inhibition.
Conclusion
A new series of quinolinylaminopyrimidines 1a–k and quinazo-
linylmethylaminopyrimidines 2a–i was designed and synthesized
as a continuation of our ongoing anticancer development research
project. The target compounds were evaluated for antiproliferative

DOI: 10.3109/14756366.2014.958082
Quinolinylaminopyrimidines and quinazolinylmethylaminopyrimidines
7
N
N
N
N
N
N
ii
i
iii
R
H N
R
O N
O N
2
2
2
N
H
N
N
Cl
Cl
N
H
N
N
5
H
H
1a-k
2
3
6a-k
iv
N
N
R
H N-R
N
Cl
H N
H N
N
N
2
2
2
H
4
5
Scheme 1. Reagents and reaction conditions: (i) HNO3, H2SO4, rt, 4 h; (ii) NaOtBu, DMF, rt, 4 h; (iii) 5% Pd/C, H2, MeOH, rt, 1 h; (iv) Pd(OAc)2,
BINAP, CsCO3, toluene, reflux, 6 h.
NH
2
N
N
N
NH
N
NH
i
ii
iii
iv
HO C
2
Cl
Br
O
Br
O
10
9
7
8
N
N
N
N
N
v
R
N
N
N
N
H
N
Br
5
H
H
H
2a-i
11
Scheme 2. Reagents and reaction conditions: (i) formamidine acetate, HCONH2, 160 ꢀC, 12 h; (ii) N-bromosuccinimide, AIBN, CCl4, rt, 24 h; (iii)
POCl3, N,N-dimethylaniline, toluene, reflux, 4 h; (iv) methylamine, THF, rt, 12 h; (v) NaOtBu, DMF, rt, 4 h.
6. Garbe C, Eigentler TK. Diagnosis and treatment of cutaneous
activities against A375P human melanoma cell line. Compounds
melanoma: state of the art 2006. Melanoma Res 2007;17:
117–27.
1h and 1k with sub-micromolar IC50 values exhibited superior
antiproliferative activity to Sorafenib. The representative com-
7. Koon HB, Atkins MB. Update on therapy for melanoma:
pound 1h possessing 3-chloro-5-trifluoromethylphenyl as a ter-
minal group showed significant and dose-dependent ERK kinase
opportunities for patient selection and overcoming tumor resistance.
Expert Rev Anticancer Ther 2007;7:79–88.
inhibitory activity. It can be considered as a promising lead for
future development of antiproliferative agents targeting ERK
pathway for treatment of melanoma.
8. Smith RA, Dumas J, Adnane L, Wilhelm SM. Recent advances in
the research and development of RAF kinase inhibitors. Curr Top
Med Chem 2006;6:1071–89.
9. Wilhelm SM, Carter C, Tang L, et al. BAY 43-9006 exhibits broad
spectrum oral antitumor activity and targets the RAF/MEK/ERK
pathway and receptor tyrosine kinases involved in tumor progression
and angiogenesis. Cancer Res 2004;64:7099–109.
10. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/
2011/ucm268241.htm.
11. Nam BS, Kim H, Oh C-H, et al. Aminoquinoline derivatives with
antiproliferative activity against melanoma cell line. Bioorg Med
Chem Lett 2009;19:3517–20.
Declaration of interest
The authors report no conflicts of interest. The authors alone are
responsible for the content and writing of the paper.
This work was funded by the KIST Institutional Program (Grant No.
2E24760) from Korea Institute of Science and Technology, and by the
Creative Fusion Research Program (Grant No. CAP-12-1) from Korea
Research Council of Fundamental Science and Technology.
12. Jung M-H, Kim H, Choi W-K, et al. Synthesis of pyrrolo[2,3-
d]pyrimidine derivatives and their antiproliferative activity
against melanoma cell line. Bioorg Med Chem Lett 2009;19:
6538–43.
13. Kim HJ, Jung M-H, Kim H, et al. Synthesis and antiproliferative
activity of pyrrolo[3,2-b]pyridine derivatives against melanoma.
Bioorg Med Chem Lett 2010;20:413–17.
14. Lee J, Kim H, Yu H, et al. Discovery and initial SAR of pyrimidin-4-
yl-1H-imidazole derivatives with antiproliferative activity against
melanoma cell lines. Bioorg Med Chem Lett 201;20:1573–7.
15. Yu H, Jung Y, Kim H, et al. 1, 4-Dihydropyrazolo[4,3-d]imidazole
phenyl derivatives: a novel type II Raf kinase inhibitors. Bioorg Med
Chem Lett 2010;20:3805–8.
16. Lee J, Nam BS, Kim H, et al. Synthesis of aminoquinazoline
derivatives and their antiproliferative activities against melanoma
cell line. Bioorg Med Chem Lett 2010;20:5722–5.
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