Solvent-free, microwave assisted synthesis of polyhalo heterocyclic ketene aminals as novel anti-cancer agents

Article abstract of DOI:10.1016/j.bmcl.2009.11.044

A series of polyhalo heterocyclic ketene aminals (polyhalo-HKAs) were synthesized under solvent-free conditions and evaluated in vitro against a panel of human tumor cell lines. Trifluoro-HKAs were the most cytotoxic compounds, followed by difluoro-HKAs and trichloro-HKAs. Trichloro-HKAs were more potent against the tumor cell lines Skov-3, Hep-2, K562, and A431 than difluoro-HKAs. An ethoxycarbonyl at the 2-position of the polyhalo HKAs gave the highest activity. Ethoxycarbonyl substituted 5o, bearing three fluorine atoms on the isophthalonitrile ring, was found to be the most potent derivative with IC₅₀ values lower than 3.7 μg/mL against five human tumor cell lines making it more active than cisplatin (DDP).

Full text of DOI:10.1016/j.bmcl.2009.11.044

Bioorganic & Medicinal Chemistry Letters 20 (2010) 48–51
Contents lists available at ScienceDirect
Bioorganic & Medicinal Chemistry Letters
journal homepage: www.elsevier.com/locate/bmcl
Solvent-free, microwave assisted synthesis of polyhalo heterocyclic ketene
aminals as novel anti-cancer agents
*
Sheng-Jiao Yan , Chao Huang , Xiang-Hui Zeng, Rong Huang, Jun Lin
Key Laboratory of Medicinal Chemistry for Natural Resource (Yunnan University), Ministry of Education, School of Chemical Science and Technology, Yunnan University,
Kunming 650091, 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 polyhalo heterocyclic ketene aminals (polyhalo-HKAs) were synthesized under solvent-free
conditions and evaluated in vitro against a panel of human tumor cell lines. Trifluoro-HKAs were the
most cytotoxic compounds, followed by difluoro-HKAs and trichloro-HKAs. Trichloro-HKAs were more
potent against the tumor cell lines Skov-3, Hep-2, K562, and A431 than difluoro-HKAs. An ethoxycar-
bonyl at the 2-position of the polyhalo HKAs gave the highest activity. Ethoxycarbonyl substituted 5o,
bearing three fluorine atoms on the isophthalonitrile ring, was found to be the most potent derivative
Received 8 September 2009
Revised 6 November 2009
Accepted 11 November 2009
Available online 16 November 2009
Keywords:
Polyhalo heterocyclic ketene aminals
Solvent-free
Microwave assisted synthesis
C-Arylation
with IC50 values lower than 3.7
cisplatin (DDP).
lg/mL against five human tumor cell lines making it more active than
Ó 2009 Elsevier Ltd. All rights reserved.
Heterocyclic ketene aminals (HKAs) have been frequently iden-
tified as pharmacophores and play important roles in drug discov-
ery. As a type of versatile synthetic intermediates, HKAs have been
utilized for the synthesis of a wide variety of heterocyclic and fused
heterocyclic compounds,1 including herbicides, pesticides,2 anti-
anxious agents,3 antileishmanial agents,4 antibacterial and anti-
therapeutic drugs.5 Overall, great progress on the synthesis of
HKAs and their applications has been achieved.6 Notably, HKAs
can react with either alkyl halides,7,8 activated acetylenes or elec-
trophilic olefins6,8 under neutral conditions to give exclusively
the C-alkylated products. This is understandable because of the
opportunities to construct molecule libraries which can be for
screened for biological activity against a variety targets.
However, to the best of our knowledge, no C-arylation has been
observed between HKAs and halobenzenes under neutral condi-
tions. Only the anion of HKAs, which were coped with NaH, can re-
act with 2,4-dinitrohalobenzenes to afford C-arylated products
with very lower yields (26–44%) via a radical nucleophilic mecha-
nism.11 According to the literature,
a-carbon substituted products
form under neutral conditions, and N-substituted products form
under basic conditions.1,7 To obtain the C-arylation products with
highly selective and good yields, neutral conditions are necessary.
An efficient method for the facile construction of HKAs molecu-
lar libraries through arylation with polyhalo isophthalonitriles un-
der neutral and solvent-free conditions was developed. The
compounds were evaluated in vitro against a panel of human tu-
mor cell lines.
stronger nucleophilicity of the
a-carbon in comparison with the
nitrogen atom in HKAs, for example, 1a, as shown in Scheme 1.
Polyhalo isophthalonitriles, especially polyfluoro isophthalo-
nitriles, have been widely used as antibacterial and anti-inflamma-
tory agents or synthetic materials in organic synthesis.9
Consequently, fluorine-containing HKAs have attracted consid-
erable attention in the field of pharmaceutical chemistry, because
of the lipophilicity of fluorine and the improved activity profile
originating from its superior metabolic stability.10
Furthermore, such hybrid molecules containing HKAs and poly-
fluoro isophthalonitriles possess biological activities, which may
lead to the enhancement of the activity of either component alone
and may result in novel biological applications. In addition, the hal-
ogens and the cyano group can be readily derived, providing many
To examine the practicality of the projected synthetic route, a
set of experiments were carried out using 2-(imidazolidin-2-yli-
NH O
Cl
NC
Cl
Cl
N
H
Ph
Cl
NH O
Solvent-free
MW
Cl
CN
4a
N
H
NC
Ph
1a
Cl
Cl
CN
5a
* Corresponding author. Tel./fax: +86 871 5033215.
E-mail address: linjun@ynu.edu.cn (J. Lin).
Scheme 1. Reaction of HKAs 1a with polyhalo isophthalonitrile 4a in solvent-free
These authors contributed equally to this Letter.
conditions under microwave irradiation.
0960-894X/$ - see front matter Ó 2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.bmcl.2009.11.044

S.-J. Yan et al. / Bioorg. Med. Chem. Lett. 20 (2010) 48–51
49
Table 1
O
X
NH
R1
Y
Synthesis of 5a in solvent-free under microwave irradiation
X
X
Y
O
n NH
NC
R1
Yielda (%)
Solvent-free
NH
Entry
Power
T (°C)
Time (min)
NC
R2
R2
n NH H
1: n=0
2: n=1
3: n=2
MW: 200W
1
2
3
4
5
6
7
8
9
MW/170 W
MW/170 W
MW/170 W
MW/200 W
MW/200 W
MW/200 W
MW/230 W
MW/230 W
MW/230 W
110
120
130
110
120
130
110
120
130
12
12
12
12
12
12
12
12
12
70
88
86
70
89
84
71
87
80
CN
120 ºC, 12 min
CN
4
5: n=0
6: n=1
7: n=2
Scheme 2. Synthesis of polyhalo HKAs.
a
Isolated yield based on HKAs 1a.
23). On the other hand, the substituents and members of the ring
in HKAs only slightly influenced the reactivity (e.g., 1, 5, 8, 13,
16, 18, 21).
dene)-1-phenyl-ethanone 1a and 2,4,5,6-tetrachloroisophthalonit-
rile 4a as model substrates under microwave irradiation (MW) in
solvent-free conditions (Scheme 1). After screening different tem-
peratures and determining the maximum power of microwave
irradiation, we found that the optimum reaction conditions to form
the product 5a were 120 °C for 12 min with a maximum power of
200 W (Table 1, entry 5).
These results stimulated us to further explore the utility and
scope of the present protocol by using various HKAs 1–3 with a
range of halogenated isophthalonitriles 4, as shown in Scheme 2.
As a result, this methodology was found to be applicable to a di-
verse set of HKAs, with various substituents and rings (1–3), and
polyhalogen isophthalonitriles (4a–c), producing the correspond-
ing C-arylation products (Table 2).
All new compounds were fully characterized using 19F NMR, 1H
NMR, 13C NMR and high resolution mass spectrometry.12 The suc-
cessful synthesis of the C-arylation products rather than the N-ary-
lation products was proven by 1H NMR. For example, compound 5b
has two active hydrogen atoms with a chemical shift of 6.65 (br,
1H, NH) and 9.97 (br, 1H, NH). However, the N-arylation product
would have only had one active hydrogen atom. The two active
hydrogen atoms have also been confirmed by D2O exchange exper-
iments. In addition, the C-arylation product 5o was cyclized to
form polyhalo isoquinolin-1(2H)-imine, whose structure was con-
firmed by X-ray analysis (CCDC 736001).13 The regiospecificity of
nucleophilic displacement at the 4-position of 4 by HKAs 1–3
was verified by physical and spectral properties. It was shown by
13C NMR that the isophthalonitrile ring of 5–7 were unsymmetric
with six aromatic resonances.
Notably, the C-arylation products 5–7 were attained exclusively
in most cases. This is ascribed to the stronger nucleophilicity of the
a
-carbon compared with that of the nitrogen atom,1,6 and the elec-
The newly synthesized polyhalo HKAs 5–7 were evaluated for
in vitro anti-cancer activity against human cells according to pro-
cedures described in the literature.14 The tumor cell line panel con-
sisted of myeloid leukaemia (HL-60 and K562), epidermoid
carcinoma (A431), ovarian carcinoma (Skov-3), and laryngeal car-
cinoma (Hep-2) cells. Cisplatin (DDP) was used as the reference
drug. The results of the cytotoxicity studies are summarized in Ta-
ble 3 and Scheme 3 (IC50 value, defined as the concentration corre-
sponding to 50% growth inhibition).
tronic effect of the ortho- and para-cyano groups. The 2-site of the
aryl ring in 4 was deactivated as a result of the steric effect of the
two ortho-cyano groups, thus leading to nucleophilic attack specif-
ically at the 4-position of the aromatic ring.9a
It is worth mentioning that the structure of the polyhalo isopht-
halonitriles 4 have obvious influence on the reaction. The reactivity
of 4 varied with the electron-withdrawing properties of the groups
(R0, X and Y) on the aromatic ring. The reactivity order of polyhalo
isophthalonitrile under the typical conditions was found to be
4c > 4b > 4a (Table 2, entries 1–3, 5–7, 8–10, 13–15, 18–20, 21–
As shown in Table 3, some of the compounds showed excellent
activity against the antitumor cells. In fact 5n and 5o are up to 155
Table 2
Synthesis of various polyhalo HKAs using the solvent-free protocol
Entry
HKAs
Polyhalo-benzonitrile
Product
n
R1
R2
X
Y
Power/Temp
Time (min)
Yielda (%)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
1a
1a
1a
1a
1b
1b
1b
1c
1c
1c
1d
1d
1e
1e
1e
1f
1f
2
4a
4b
4c
4d
4a
4b
4c
4a
4b
4c
4a
4b
4a
4b
4c
4a
4b
4a
4b
4c
4a
4b
4c
5a
5b
5c
5d
5e
5f
5g
5h
5i
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
2
2
2
Ph
Ph
Ph
Ph
Cl
F
F
PhNH
Cl
F
F
Cl
F
F
Cl
F
Cl
F
F
Cl
F
Cl
F
F
Cl
F
Cl
F
F
F
Cl
F
F
Cl
F
F
Cl
F
Cl
F
F
Cl
F
Cl
F
F
Cl
F
Cl
Cl
F
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
200 W/120 °C
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
12
89
93
98
84
85
91
98
83
89
92
81
86
93
93
95
92
94
82
87
96
86
89
96
F
p-ClC6H4
p-ClC6H4
p-ClC6H4
p-MeC6H4
p-MeC6H4
p-MeC6H4
p-MeOC6H4
p-MeOC6H4
OEt
OEt
OEt
Me
Me
p-FC6H4
p-FC6H4
p-FC6H4
Ph
Ph
ph
Cl
Cl
F
Cl
Cl
F
Cl
Cl
Cl
Cl
F
Cl
Cl
Cl
Cl
F
5j
5k
5l
5m
5n
5o
5p
5q
6a
6b
6c
7a
7b
7c
2
2
3
3
Cl
Cl
F
3
F
F
a
Isolated yields based on HKAs.

50
S.-J. Yan et al. / Bioorg. Med. Chem. Lett. 20 (2010) 48–51
Table 3
tumor cell lines and is 100 times more active than cisplatin
Cytotoxic activities of polyhalo HKAs in vitroa (IC50
,
l
g/mLb)
Skov-3
(DDP) in some cell lines (Table 3, entry 15). These results suggested
that substitution of the 2-position with an electron withdrawing
group played a vital role in the modulation of the cytotoxic activ-
ities (Scheme 3).
In conclusion, a number of novel polyhalo HKAs derivatives
were prepared and proven to have remarkably potent antitumor
activities. The substitution of the 2-position of HKAs with an elec-
tron withdrawing group (COOEt) such as 5n and 5o, which con-
tained two fluorine atoms or three fluorine atoms on the ring of
isophthalonitrile proved to be most favorable. Compounds 5n
and 5o are the most promising leads for further structural modifi-
cations guided by the valuable information provided from the de-
tailed SARs described here.
No.
Compound
HL60
HepG-2
A431
K562
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
5a
5b
5c
9.1
4.7
0.2
10.2
32.6
9.1
9.9
32.6
30.3
0.2
1.6
8.6
3.8
9.2
6.7
2.0
6.4
1.1
4.1
4.9
3.3
14.1
1.5
10.4
8.2
0.5
2.3
87.1
5.5
5.3
1.5
1.8
3.2
4.1
1.7
0.5
0.5
0.7
0.2
3.9
3.7
1.5
2.9
1.1
0.9
1.8
1.0
1.5
1.9
2.3
8.5
20.8
19.6
5.6
0.8
1.6
5d
5e
0.3
0.5
102
5.2
5f
5g
5h
5i
5j
5k
5l
5m
0.3
0.3
47.5
12.5
15.8
49.1
29.2
10.8
9.8
1.8
1.4
15.7
0.03
0.04
2.3
0.05
0.4
41.9
0.9
0.08
22.6
0.5
0.09
0.03
0.1
4.4
0.2
1.8
2.5
0.2
5n
5o
5p
0.02
0.02
3.7
2.5
0.7
5.8
Acknowledgments
5q
0.3
1.3
The authors wish to acknowledge the financial support of
grants from NSFCs (Nos. 30860342, 20762013).
6a
6b
6c
7a
7b
7c
2.1
0.6
0.04
0.2
0.1
31.8
45.1
11.0
14.5
27.8
24.9
8.2
2.7
4.6
4.2
10.7
0.1
2.1
0.3
8.5
Supplementary data
0.1
3.1
Cisplatin (DDP)
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.bmcl.2009.11.044.
a
Cytotoxicity as IC50 for each cell line, is the concentration of compound which
reduced by 50% the optical density of treated cells with respect to untreated cells
using the MTT assay.
References and notes
b
Data represent the mean values of three independent determinations.
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X
Y
CN
X
F
O
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F
CN
F
R
O
CN
HN NH
EtO
CN
HN NH
X, Y = F, F>Cl, Cl>F, Cl
R = COOEt>p-MeOPh>
p-MePh≈ p-ClPh>COMe>Ph
Best potent compound: 5o
Scheme 3. Structure–activity relationship of polyhalo HKAs.
6. (a) Muhammd, Y.; Yu, C. Y.; Jia, Y. M.; Huang, Z. T. Synlett 2008, 1357; (b) Yu, C.
Y.; Yang, P. H.; Zhao, M. X.; Huang, Z. T. Synlett 2006, 1835; (c) Liao, J. P.; Zhang,
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A. J. PCT, Int. Appl. CN101029053, 2006.; (f) Yu, C. Y.; Yan, S. J.; Zhang, T.;
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times more active than cisplatin against HL60 cells. Compound 5o
is almost 300 times more active against K562 cells than cisplatin.
The data indicates that five-membered heterocyclic ketene ami-
nals 5a–5c with a benzoyl substituent at the 2-position of the HKAs
ring have lower activity towards all tumor cell lines (Table 3, en-
tries 1–3). However, five-membered heterocyclic ketene aminals
5e–q (except 5h) with substituted benzoyl, acetyl, and ethoxycar-
bonyl substituents at position-2 of the HKAs ring exhibited excel-
lent cytotoxic activities (entries 5–7, 9–17). Among them,
compound 5o, bearing ethoxycarbonyl substituents, was the most
active (entry 15). Compared with all polyhalo-substituted deriva-
tives 5–7, 2,4,5-trifluoro substituted HKAs (trifluoro-HKAs) had
better activity than the 2,4-difluoro-5-chloro substituted HKAs (di-
fluoro-HKAs) and 2,4,5-trichloro substituted HKAs (trichloro-
HKAs), such as 5c, 5g, 5j, 5o, 6c, and 7c. Trichloro-HKAs were more
potent against the tumor cell lines Skov-3, Hep-2, K562, and A431
than difluoro-HKAs, for example 5a, 5e, 5h, 5m, 6a and 7a. Di-
fluoro-HKAs had higher activities against HL60 than trichloro-
HKAs, such as 5b, 5f, 5i, 5l, 5n, 5q, 6b, and 7b. Trifluoro-HKAs
had excellent activities against HL60 and K562. Difluoro-HKAs
were active against HL60 while trifluoro-HKAs were active against
K562 cells. Most of these compounds were more active against
HL60, Skov-3, K562, and A431 cells than DDP. However these com-
pounds had only moderate activities against HepG-2 cells. Com-
pound 5o was found to be the most potent against the 5 human
8. Jones, R. C. F.; Hirst, S. C. Tetrahedron Lett. 1989, 29, 5005.
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2008, 37, 237.
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12. General procedure: A dry mortar was charged with HKAs 1–3 (1 mmol) and
polyhalo isophthalonitrile 4 (1.1 mmol). The mixture was mixed at room
temperature by vigorously grinding with a pestle for a few minutes (ca. 1–
2 min). The mixture was placed in a microwave tube and irradiated in a
microwave reactor (Discover), with control of power and temperature by
infrared detection, at 120 °C for 12 min (maximum power 200 W). After
completion, the reaction mixture was purified by column chromatography
(petrol/ethyl acetate = 1:3, v/v) on silica-gel to give the desired products 5–7.
Compound 5a: yellow solid, mp 263–265 °C. IR (KBr): 3425, 3248, 2236, 1598,

S.-J. Yan et al. / Bioorg. Med. Chem. Lett. 20 (2010) 48–51
51
1538, 1320, 649 cmꢀ1
;
1H NMR (500 MHz, DMSO-d6) d 3.51 (s, 2H, CH2), 3.74 (s,
162.4, 165.5. 19F NMR (470 MHz, DMSO-d6) d ꢀ95.7 (s, 1F), ꢀ102.5 (s, 1F).
2H, CH2), 7.03–7.25 (m, 6H, PhH, NH), 9.66 (br, 1H, NH); 13C NMR (125 MHz,
DMSO-d6) d 42.2, 44.2, 88.1, 113.2, 113.7, 114.3, 118.8, 127.2, 128.0, 129.3,
137.1, 138.2, 140.4, 142.4, 149.8, 163.2, 184.7; HRMS (TOF ES+): m/z calcd for
C19H11Cl3N4NaO+ [(M+Na)+], 438.9891; found, 438.9898. Compound 5b: yellow
solid, mp >300 °C. IR (KBr): 3208, 3144, 2244, 1588, 1536, 1319, 1091,
HRMS (TOF ESꢀ): m/z calcd for C15H10ClF2N4O2 [MꢀH+], 351.0466; found,
ꢀ
351.0470. Compound 5o: yellow solid, mp 169–170 °C. IR (KBr): 3347, 2984,
2894, 2245, 1648, 1100 cmꢀ1 1H NMR (500 MHz, DMSO-d6) d 1.10–1.13 (m,
.
3H, CH3), 3.54–3.61 (m, 4H, NCH2), 4.00–4.02 (m, 2H, OCH2), 7.19 (br, 1H, NH),
8.32 (br, 1H, NH). 13C NMR (125 MHz, DMSO-d6) d 14.7, 43.0, 43.9, 58.6, 66.6,
90.3 (t, J = 18.8 Hz), 102.2 (d, J = 11.3 Hz), 108.4, 111.9, 139.0 (d, J = 13.8 Hz),
145.4 (d, J = 240 Hz), 153.4 (dd, J = 271.3, 18.8 Hz), 159.9 (d, J = 262.5 Hz),
162.7, 165.6. 19F NMR (470 MHz, DMSO-d6) d ꢀ106.1 (d, J = 9.3 Hz, 1F), ꢀ121.2
(d, J = 14.0 Hz, 1F), ꢀ134.1 (m, 1F). HRMS (TOF ES+): m/z calcd for
666 cmꢀ1 1H NMR (500 MHz, acetone-d6) d 3.66 (s, 2H, CH2), 3.92 (s, 2H, CH2),
.
6.65 (br, 1H, NH) 7.19–7.25 (m, 5H, PhH), 9.97 (br, 1 H, NH). 13C NMR
(125 MHz, acetone-d6) d 43.7, 45.3, 87.2, 93.2, 105.9, 108.7, 112.3, 123.4, 128.7,
128.8, 130.3, 143.5, 152.2, 161.3, 163.0 (d, J = 92.5 Hz), 165.0, 187.2. 19F NMR
(470 MHz, acetone-d6) d ꢀ94.8 (s, 1F), ꢀ101.4 (s, 1F). HRMS (TOF ES+): m/z
calcd for C19H11ClF2N4NaO+ [(M+Na)+], 407.0482; found, 407.0484. 9i 5c:
yellow solid, mp 178 °C. IR (KBr): 3392, 3239, 2244, 1592, 1538, 1319, 1043,
C15H11F3N4NaO2 [(M+Na)+], 359.0726; found, 359.0724. Compound 6a:
þ
yellow solid, mp 233–234 °C. IR (KBr): 3444, 3246, 1709, 1600, 1518, 1359,
597 cmꢀ1 1H NMR (500 MHz, DMSO-d6) d 1.87 (s, 2H, CH2) 3.20–3.44 (m, 4H,
.
666 cmꢀ1
.
1H NMR (500 MHz, acetone-d6) d 3.71 (s, 2H, CH2), 3.93 (s, 2H, CH2),
CH2), 6.67 (br, 1H, NH), 7.00–7.01 (m, 4H, ArH), 11.43 (br, 1H, NH). 13C NMR
(125 MHz, DMSO-d6) d 21.3,39.8, 39.8, 91.9, 114.6, 115.4, 115.7, 116.2 (d,
J = 21.3 Hz), 121.0, 130.7 (d, J = 6.3 Hz), 139.1, 139.7, 140.7, 142.0, 150.8, 158.9,
163.5 (d, J = 243.8 Hz), 183.3. HRMS (TOF ES+): m/z calcd for C20H12Cl3FN4NaO+
[(M+Na)+], 470.9953; found, 470.9963. Compound 6b: yellow solid, mp 228–
6.72 (br, 1H, NH), 7.20–7.30 (m, 5H, PhH), 10.04 (br, 1 H, NH). 13C NMR
(125 MHz, acetone-d6) d 43.6, 45.4, 82.0, 92.8, 104.1, 108.6, 112.1, 128.9, 130.3,
141.7, 143.3, 146.0, 148.0, 154.9 (d, J = 247.5 Hz), 161.3 (d, J = 246.3 Hz), 165.3,
187.8. 19F NMR (470 MHz, acetone-d6) d ꢀ104.7 (d, J = 9.3 Hz, 1F), ꢀ120.2 (d,
J = 23.4 Hz, 1F), ꢀ134.1 (m, 1F). HRMS (TOF ES+): m/z calcd for C19H12F3N4O
[M+], 369.0958; found, 369.0967. Compound 5d: yellow solid, mp 158–160 °C.
230 °C. IR (KBr): 3399, 3264, 2245, 1729, 1605, 1517, 1354, 601 cmꢀ1 1H NMR
.
(500 MHz, DMSO-d6) d 1.87–1.88 (m, 2H, CH2) 3.32–3.38 (m, 5H, CH2, NH),
6.97–7.19 (m, 4H, PArH). 13C NMR (125 MHz, DMSO-d6) d 21.1, 38.4, 38.4, 88.2,
104.9, 108.3, 111.7, 114.8 (d, J = 21.3 Hz), 122.6, 129.6, 139.1, 150.6, 157.5,
159.9, 161.3 (d, J = 31.3 Hz), 163.2, 162.8 (d, J = 191.3 Hz), 182.1. HRMS (TOF
ES+): m/z calcd for C20H12ClF3N4NaO+ [(M+Na)+], 439.0544; found, 439.0551.
Compound 6c: yellow solid, mp 195–196 °C. IR (KBr): 3414, 3268, 2245, 1706,
IR (KBr): 3381, 3054, 2230, 1592, 1527, 1317, 1042, 700 cmꢀ1 1H NMR
.
(500 MHz, DMSO-d6) d 3.51 (s, 2H, CH2), 3.70–3.74 (m, 2H, CH2), 6.69–7.08 (m,
5H, PhH) 7.12–7.14 (m, 1H, NH) 7.21–7.34 (m, 5H, PhH), 9.37 (br, 1H, NH), 9.71
(br, 1H, NH). 13C NMR (125 MHz, DMSO-d6) d 42.3, 44.2, 89.3 (d, J = 15.0 Hz),
94.7 (d, J = 12.5 Hz), 111.1, 113.1, 117.1, 121.1, 124.4, 127.3, 128.0, 129.1,
129.2, 135.4 (d, J = 20.0 Hz), 139.7 (d, J = 13.8 Hz), 140.2, 142.7, 148.1 (d,
J = 258.8 Hz), 162.5 (d, J = 258.8 Hz), 163.7, 185.5. HRMS (TOF ES+): m/z calcd
for C25H18F2N5O [M+], 442.1474; found, 442.1480. Compound 5e: yellow solid,
1599, 1518, 1313, 601 cmꢀ1 1H NMR (500 MHz, Acetone-d6) d 1.98–2.07 (m,
.
3H, CH2, NH), 3.45 (s, 4H, CH2), 6.92–7.20 (m, 5H, ArH, NH). 13C NMR (125 MHz,
Acetone-d6) d 21.1, 39.7, 39.7, 84.1, 93.1 (d, J = 17.5 Hz), 104.9 (d, J = 12.5 Hz),
108.5, 112.2, 115.7 (d, J = 21.3 Hz), 130.8 (d, J = 6.3 Hz), 140.2, 141.1 (d,
J = 17.5 Hz), 147.6 (d, J = 241.3 Hz), 155.0 (dd, J = 267.5, 17.5 Hz), 159.3, 161.5
(d, J = 265.0 Hz), 163.8 (d, J = 245.0 Hz), 185.1. HRMS (TOF ES+): m/z calcd for
C20H12F4N4NaO+ [(M+Na)+], 423.0839; found, 423.0840. Compound 7a: yellow
mp 256–258 °C. IR (KBr): 3426, 3234, 2356, 1598, 1539, 1320, 628 cmꢀ1 1H
.
NMR (500 MHz, DMSO-d6) d 3.51 (s, 2H, CH2), 3.73–3.74 (m, 2H, CH2), 7.05–
7.28 (m, 5H, ArH, NH) 9.64 (br, 1H, NH). 13C NMR (125 MHz, DMSO-d6) d 42.2,
44.2, 88.0, 113.2, 114.1, 114.3, 118.6, 128.2, 129.2, 133.8, 136.9, 138.5, 140.7,
141.0, 149.2, 163.2, 183.1. HRMS (TOF ES+): m/z calcd for C19H10Cl4N4NaO+
[(M+Na)+], 472.9501; found, 472.9511. Compound 5f: yellow solid, mp 210–
solid, mp 220–223 °C. IR (KBr): 3383, 3255, 2237, 1614, 1357, 649 cmꢀ1 1H
.
NMR (500 MHz, DMSO-d6) d 1.31–1.74 (m, 4H, CH2) 3.12–3.48 (m, 4H, CH2),
6.37 (br, 1H, NH), 6.96–7.64 (m, 5H, PhH), 11.27 (br, 1H, NH). 13C NMR
(125 MHz, DMSO-d6) d 27.3, 27.4, 44.7, 45.3, 93.2, 113.2, 113.4, 114.4, 119.3,
126.9, 127.9, 128.9, 137.3, 138.3, 140.3, 142.7, 150.3, 166.5, 185.5. HRMS (TOF
ES+): m/z calcd for C21H15Cl3N4NaO+ [(M+Na)+], 467.0204; found, 467.0213.
Compound 7b: yellow solid, mp 207–210 °C. IR (KBr): 3384, 3269, 2243, 1614,
211 °C. IR (KBr): 3414, 3250, 2365, 2245, 1587, 1538, 1323, 642 cmꢀ1 1H NMR
.
(500 MHz, DMSO-d6) d 3.57 (s, 2H, CH2), 3.71 (s, 2H, CH2), 7.08–7.27 (m, 5H,
ArH, NH) 9.67 (br, 1H, NH). 13C NMR (125 MHz, DMSO-d6) d 42.2, 44.0, 85.8,
92.1 (t, J = 20.0 Hz), 104.1 (d, J = 13.8 Hz), 108.3, 111.7, 121.9 (d, J = 10.0 Hz),
128.2, 129.4, 134.0, 140.9, 150.3, 160.7 (d, J = 191.3 Hz), 162.8 (d, J = 143.8 Hz),
163.2, 183.3. HRMS (TOF ES+): m/z calcd for C19H10Cl2F2N4NaO+ [(M+Na)+],
441.0092; found, 441.0098. Compound 5g: yellow solid, mp 180–181 °C. IR
1350, 703 cmꢀ1 1H NMR (500 MHz, DMSO-d6) d 1.34–1.71 (m, 4H, CH2), 3.14–
.
3.46 (m, 4H, CH2), 6.39 (br, 1H, NH), 7.01–7.46 (m, 5H, PhH), 11.21 (br, 1H, NH).
13C NMR (125 MHz, DMSO-d6) d 27.3, 27.3, 44.8, 45.3, 91.1–91.5 (m), 104.6,
108.2, 111.8, 122.3, 127.2, 127.9, 129.1, 142.6, 151.6, 159.8, 161.7 (d,
J = 50.0 Hz), 163.6, 166.7, 185.8. HRMS (TOF ES+): m/z calcd for
C21H15ClF2N4NaO+ [(M+Na)+], 435.0795; found, 435.0806. Compound 7c:
yellow solid, mp 178–179 °C. IR (KBr): 3384, 3254, 2242, 1602, 1352,
(KBr): 3397, 3242, 2245, 1594, 1538, 1321, 647 cmꢀ1 1H NMR (500 MHz,
.
DMSO-d6) d 3.65 (s, 4H, CH2), 7.12–7.27 (m, 5H, ArH, NH) 9.67 (br, 1H, NH). 13
C
NMR (125 MHz, DMSO-d6) d 43.3, 45.4, 80.7, 91.6 (t, J = 18.8 Hz), 102.5 (d,
J = 11.3 Hz), 108.2, 111.6, 128.2, 129.6, 134.1, 139.8 (d, J = 17.5 Hz), 140.6,
145.5 (d, J = 248.8 Hz), 153.5 (dd, J = 270.0, 15.0 Hz), 160.1 (d, J = 263.8 Hz),
163.4, 184.5. HRMS (TOF ES+): m/z calcd for C19H11ClF3N4O [M+], 403.0568;
found, 403.0568. Compound 5m: yellow solid, mp 199–200 °C. IR (KBr): 3371,
630 cmꢀ1
.
1H NMR (500 MHz, DMSO-d6) d 1.53 (s, 4H, CH2) 3.00–3.36 (m,
13
4H, CH2), 7.32–7.90 (m, 6H, PhH, NH).
C NMR (125 MHz, DMSO-d6) d 27.1,
2982, 2889, 2239, 1657, 1101 cmꢀ1
.
1H NMR (500 MHz, DMSO-d6) d 1.06 (t,
27.1, 45.1, 45.1, 89.1, 108.7, 112.0, 128.0, 128.6, 128.9, 129.5, 131.0, 142.1,
143.0 (m), 145.2 (m), 152.8 (d, J = 257.5 Hz), 160.6 (d, J = 260.0 Hz), 167.2,
187.5. HRMS (TOF ES+): m/z calcd for C21H15F3N4NaO+ [(M+Na)+], 419.1090;
found, 419.1098.
J = 6.35 Hz, 3H, CH3), 3.45–3.47 (m, 2H, NCH2), 3.61–3.65 (m, 2H, NCH2), 3.96
(m, 2H, OCH2), 6.93 (br, 1H, NH), 8.12 (br, 1H, NH). 13C NMR (125 MHz, DMSO-
d6) d 15.0, 42.6, 44.0, 58.3, 73.0, 113.3, 113.3, 114.5, 118.6, 136.9, 13ꢀ8.0, 140.1,
148.6, 162.3, 165.5. HRMS (TOF ES-): m/z calcd for C15H10Cl3N4O [MꢀH+],
382.9875; found, 382.9877. Compound 5n: yellow solid, mp 1862–187 °C. IR
13. The Cambridge Crystallographic Data Center via www.ccdc.cam.ac.uk/
data_request/cif.
14. (a) Kim, D. K.; Ryu, D. H.; Lee, J. Y.; Lee, N.; Kim, Y. W.; Kim, J. S.; Chang, K.; Im,
G. J.; Kim, T. K.; Choi, W. S. J. Med. Chem. 2001, 44, 1594; (b) Carmichael, J.;
DeGraff, W. G.; Gazdar, A. F.; Minna, J. D.; Mitchell, J. B. Cancer Res. 1987, 47,
936; (c) Mossman, T. J. Immunol. Methods 1983, 65, 55.
(KBr): 3352, 2986, 2892, 2245, 1648, 1097 cmꢀ1
.
1H NMR (500 MHz, DMSO-d6)
d 1.09–1.10 (m, 3H, CH3), 3.46–3.48 (m, 2H, NCH2), 3.62–3.65 (m, 2H, NCH2),
3.97 (m, 2H, OCH2), 6.97 (br, 1H, NH), 8.19 (br, 1H, NH). 13C NMR (125 MHz,
DMSO-d6) d 14.9, 42.6, 44.0, 58.4, 71.1, 91.1 (t, J = 17.5 Hz), 103.9, 108.5, 120.0,
121.6 (d, J = 12.5 Hz), 149.7, 160.7 (d, J = 262.5 Hz), 162.3 (d, J = 262.5 Hz),