Synthesis and in Vitro Cytotoxic Activity of Novel Triazole-Isoxazole Derivatives

Article abstract of DOI:10.1002/jhet.2273

New derivatives of triazole-isoxazole were synthesized through a four-step reaction starting from various ethyl 4-aryl-2,4-dioxobutanoate derivatives. Finally, all compounds were examined by MTT assays for cytotoxic activity in two human breast cancer cell lines (MCF-7 and T-47D).

Full text of DOI:10.1002/jhet.2273

Month 2014
Synthesis and In Vitro Cytotoxic Activity of Novel Triazole-Isoxazole
Derivatives
a
b
c
b
d
e
Zahra Najafi, Mohammad Mahdavi, Maliheh Safavi, Mina Saeedi, Heshmatollah Alinezhad, Mahboobeh Pordeli,
e
b
b
a,f
Sussan Kabudanian Ardestani, Abbas Shafiee, Alireza Foroumadi, and Tahmineh Akbarzadeh *
a
Department of Medicinal Chemistry, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 14176, Iran
b
Faculty of Pharmacy and Pharmaceutical Sciences Research Center, Tehran University of Medicinal Sciences, Tehran, Iran
c
Department of Biotechnology, Iranian Research Organization for Science and Technology, Tehran, Iran
d
Faculty of Chemistry, Mazandaran University, Babolsar, Iran
e
Institute of Biochemistry and Biophysics, Department of Biochemistry, University of Tehran, Tehran, Iran
Persian Medicine and Pharmacy Research Center, Tehran University of Medical Sciences, Tehran, Iran
f
*
E-mail: akbarzad@tums.ac.ir
Additional Supporting Information may be found in the online version of this article.
Received February 24, 2014
DOI 10.1002/jhet.2273
Published online 00 Month 2014 in Wiley Online Library (wileyonlinelibrary.com).
New derivatives of triazole-isoxazole were synthesized through a four-step reaction starting from various
ethyl 4-aryl-2,4-dioxobutanoate derivatives. Finally, all compounds were examined by MTT assays for
cytotoxic activity in two human breast cancer cell lines (MCF-7 and T-47D).
J. Heterocyclic Chem., 00, 00 (2014).
INTRODUCTION
,2,3-Triazole and isoxazole derivatives; two important
RESULTS AND DISCUSSION
Chemistry. Our efforts to construct new triazole-
1
five-membered heterocycles, have shown a significant class
of privileged structures and absorbed a great deal of interest
in drug discovery. 1,2,3-Triazoles have been highly
recognized because of their cytotoxic [1], anti-HIV-1 [2],
anti-influenza [3], anti-platelet [4], and anti-tuberculosis [5]
activities. Likewise, isoxazole derivatives have attracted
enormous attention for their anti-depression [6], antipyretics
isoxazole scaffold 7 was achieved using a four-step
reaction starting from ethyl 4-aryl-2,4-dioxobutanoates 1
(Scheme 1). Various ethyl 5-arylisoxazole-3-carboxylate
2 was easily prepared according to our previous report
through the reaction of 1 and hydroxylamine hydrochloride
in ethanol at reflux [17]. Hydrolysis of ester group
in the presence of potassium hydroxide in MeOH at
reflux gave corresponding carboxylic acid 3, which
tolerated the reaction with propargyl amine in the
presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide
[7], anti-inflammatory [8], and also anti-tuberculosis [9]
properties. It seems that the combination of 1,2,3-triazole
and isoxazole scaffolds leads to the formation of compounds
possessing promising biological activities.
and hydroxybenzotriazole in CH CN to obtain related amide
3
Up to now, a few efforts has been efficiently developed
for the synthesis of compounds having both triazol and
isoxazole skeletons [10–12]. Recently, a series of N-((1-
benzyl-1H-1,2,3-triazol-4-yl)methyl)arylamides was syn-
thesized by Stefely et al. as efficient inhibitors of cancer cell
growth [13]. They exhibited in vitro antiproliferative activity
against select cancer cell lines. Good results by this study and
also lack of versatile reports in the literature encouraged us to
prepare novel triazole-isoxazole derivatives and evaluate
their cytotoxic activity. Herein, as a continuation of our work
on the synthesis of novel heterocycles [14,15] and bioactive
compounds [16] specially containing isoxazol skeleton [17],
we have aimed to develop an effective protocol for the
synthesis of triazole-isoxazole derivatives 7 as demonstrated
in Scheme 1, starting from various ethyl 4-aryl-2,4-
dioxobutanoate derivatives 1.
derivative, 3-aryl-N-(prop-2-yn-1-yl)isoxazole-5-carboxamide
derivatives 4.
Presence of triple bond in compound 4 directed us to-
ward click reaction to construct triazole ring. To achieve
this goal, we reacted 5-phenyl-N-(prop-2-yn-1-yl)isoxazole-
3-carboxamide 4a with in situ prepared (azidomethyl)benzene
6a under the name sharpless-type click reaction conditions
[18]. It was perceived that 4a reacted with 6a in the
presence of CuI (7 mol%) in H O/t-BuOH at room
2
temperature for 24 h leading to the formation of correspond-
ing product, N-((1-benzyl-1H-1,2,3-triazol-4-yl)methyl)-5-
phenylisoxazole-3-carboxamide 7a in good yields (68%).
Next, using the developed method, various triazole-
isoxazole derivatives involving different substituents on
triazole and isoxazole rings were prepared (Table 1). It is
worth to mention that all reactions were conducted either
©
2014 HeteroCorporation

Z. Najafi, M. Mahdavi, M. Safavi, M. Saeedi, H. Alinezhad, M. Pordeli,
S. Kabudanian Ardestani, A. Shafiee, A. Foroumadi, and T. Akbarzadeh
Vol 000
Scheme 1. Synthesis of triazole-isoxazole derivatives 7.
with electron-withdrawing or electron-donating groups
and desired products were obtained in good yields.
Procedure for the synthesis of 5-arylisoxazole-3-carboxylic
acid (3). A solution of ethyl 5-arylisoxazole-3-carboxylate 2
(
(
(
1 mmol) and potassium hydroxide (0.05 g, 1 mmol) in MeOH
5 mL) was heated at reflux for 3 h. After completion of reaction
checked by thin-layer chromatography), the reaction mixture
was cooled to room temperature and acidified with concentrated
hydrochloric acid (HCl). The precipitates were filtered off and
washed with water to give the corresponding products without
further purification.
Biological investigation. The in vitro cytotoxic activity
of all triazole-isoxazole derivatives 7a–l were evaluated
against two human breast cancer cell lines MCF-7 and
T-47D. All results have been summarized in Table 1. As
can be seen in Table 1, according to IC50 values, most of
compounds have no effect on the two cell lines. In MCF-
Procedure for the synthesis of 3-aryl-N-(prop-2-yn-1-yl)
isoxazole-5-carboxamide (4). A solution of 3 (1 mmol), 1-ethyl-3-
7
cell line, all compounds except 7c (Entry 3, Table 1)
had IC50 higher than 100 μg/mL. In T-47D cell line, 7d
had IC50 lower than 100 μg/mL and was the most potent
compound in this cell line.
(
3-dimethylaminopropyl)carbodiimide (0.17 g, 1.1 mmol), and
hydroxybenzotriazole (0.13g, 1 mmol) in dry acetonitrile (5mL)
was stirred at room temperature for 30 min. Then, propargylamine
(
0.05 g, 1 mmol) was added to the mixture and the reaction
CONCLUSIONS
was continued at room temperature for 24h. After completion of
reaction, the solvent was reduced under vacuum, and the residue
was dissolved in dichloromethane and washed with sodium
carbonate (10%). The organic phase was dried over Na SO ,
and the solvent was evaporated. The obtained compound was
completely pure and used for further reaction.
In conclusion, we have developed a user-friendly and ef-
fectual method for the synthesis of novel triazole-isoxazole
derivatives. The synthetic route for the synthesis of the
title compounds was achieved through a four-step reaction
starting from different ethyl 4-aryl-2,4-dioxobutanoate de-
rivatives. In addition, all compounds were evaluated for their
cytotoxic activity. Although most of compounds showed no
activity against two breast cancer cell lines MCF-7 and
T-47D, compounds 7c and 7d were found to be effective
in vitro anti-cancer agents.
2
4
Procedure for the synthesis of triazole-isoxazole derivatives
(
7). A solution of benzyl chloride derivative 5 (1.1 mmol),
sodium azide (0.06 g, 0.9 mmol), and triethylamine (0.13 g,
.3 mmol) in water (4 mL) and tert-butyl alcohol (4 mL) was
stirred at room temperature for 30 min. The prepared compound
(0.5 mmol) and CuI (7 mol%) was added to reaction mixture,
1
4
and it was continued for further 16–24 h. Upon completion of
the reaction, monitored by thin-layer chromatography, the
reaction mixture was diluted with water, poured in ice, and the
precipitated product was filtered off, washed with cold water,
and purified by flash chromatography on silica gel using
petroleum ether/ethyl acetate/dichloromethane (3:1:1) as eluent.
N-((1-Benzyl-1H-1,2,3-triazol-4-yl)methyl)-5-phenylisoxazole-
3-carboxamide (7a). White crystals; yield: 68%; mp 201–204 °C.
EXPERIMENTAL
Chemistry. Melting points were taken on a Kofler hot stage
1
13
apparatus and are uncorrected. H-NMR and C-NMR spectra
were recorded on Bruker FT-500 and FT-400 (Germany), using
tetramethylslane as an internal standard. The infrared (IR) spectra
were obtained on a Nicolet Magna FTIR 550 spectrometer (KBr
disks). The elemental analysis was performed with an Elementar
Analysensystem GmbH VarioEL CHNS mode (Germany). Mass
spectra were recorded on an Agilent Technology (HP) mass
spectrometer operating at an ionization potential of 70eV.
À1
1
IR (KBr, cm ) υ: 3415, 3124, 2928, 1663, 1615, 1542; H-NMR
500 MHz, CDCl ) δ ppm: 4.75 (s, 2H, NHCH ), 5.53 (s, 2H,
(
3
2
CH ), 6.96 (s, 1H, isoxazole), 7.28–7.30 (m, 2H, Ph), 7.37–7.40
2
(m, 3H, Ph), 7.45 (bs, 1H, NH), 7.49–7.50 (m, 3H, Ph), 7.57
13
(
s, 1H, triazole), 7.79–7.80 (m, 2H, Ph); C-NMR (100 MHz,
DMSO-d ) δ ppm: 35.0, 53.2, 100.3, 123.6, 126.2, 126.7, 128.5,
128.6, 129.2, 129.8, 131.3, 136.6, 145.1, 158.9, 159.9, 170.8; MS
Ethyl 5-arylisoxazole-3-carboxylate 2 was prepared according
to our previous report [17].
6
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

Month 2014
Triazole-Isoxazoles
Table 1
Table 1
a
Chemical structures and in vitro cytotoxic activity (IC50, μg/mL) of
triazole-isoxazole derivatives 7 (a–l) against breast cancer cell lines.
(Continued)
Entry
Product 7
MCF-7
T47D
Entry
Product 7
MCF-7
T47D
1
>100
—
7
>100
>100
2
3
4
>100
85.7 ± 4.5
>100
>100
8
9
>100
>100
>100
>100
>100
27.7 ± 0.1
10
>100
>100
5
>100
>100
11
>100
>100
6
>100
>100
1
1
2
3
>100
>100
(
Continues)
Etoposide
7.5 ± 0.32
7.9 ± 0.45
+.
(
(
m/z): 359 ([M] , 69), 240 (27), 187 (33), 172 (41), 158 (32), 143
52), 105 (55), 91 (100), 77 (33); Anal. Calcd for C H N O :
a
The IC50 values represent an average of three independent experiments
mean ± SD).
2
0 17 5 2
(
C, 66.84; H, 4.77; N, 19.49. Found: C, 66.94; H, 4.58; N, 19.23.
N-((1-(4-Methylbenzyl)-1H-1,2,3-triazol-4-yl)methyl)-5-
phenylisoxazole-3-carboxamide (7b). White crystals; yield: 58%;
1
1665, 1611, 1541; H-NMR (500 MHz, CDCl ) δ ppm: 2.36
(s, 3H, CH ), 4.73 (s, 2H, NHCH ), 5.48 (s, 2H, CH ), 6.95
(s, 1H, isoxazole), 7.18–7.20 (m, 4H, H , H , H , H ), 7.40 (bs,
2′ 3′ 5′ 6′
3
3
2
2
À1
mp 179–182 °C. IR (KBr, cm ) υ: 3390, 3127, 3072, 2925,
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

Z. Najafi, M. Mahdavi, M. Safavi, M. Saeedi, H. Alinezhad, M. Pordeli,
S. Kabudanian Ardestani, A. Shafiee, A. Foroumadi, and T. Akbarzadeh
Vol 000
1H, NH), 7.48–7.51 (m, 4H, Ph, triazole), 7.79–7.81 (m, 2H, Ph);
NHCH ), 5.49 (s, 2H, CH ), 6.84 (s, 1H, isoxazole), 6.95
2 2
Anal. Calcd for C H N O : C, 67.55; H, 5.13; N, 18.76. Found:
(d, J = 8.4 Hz, 1H, H ), 7.22 (d, J = 8.4 Hz, 2H, H , H ), 7.28
21
19
5
2
5″
2′
6′
C, 67.39; H, 5.28; N, 18.91.
N-((1-(4-Methoxybenzyl)-1H-1,2,3-triazol-4-yl)methyl)-5-
phenylisoxazole-3-carboxamide (7c). White crystals; yield: 65%;
(d, J = 1.9 Hz, 1H, H2″), 7.34–7.37 (m, 3H, H3′, H5′, H6″), 7.40
+
.
(bs, 1H, NH), 7.53 (s, 1H, triazole); MS (m/z): 455 ([M] + 2, 7),
+
.
453 ([M] , 21), 165 (57), 125 (100), 89 (84), 63 (36); Anal.
À1
mp 180–183 °C. IR (KBr, cm ) υ: 3427, 3124, 2953, 1666,
Calcd for C H ClN O : C, 58.22; H, 4.44; N, 15.43. Found:
22
20
5 4
1
1
613, 1581; H-NMR (500MHz, CDCl ) δ ppm: 3.82 (s, 3H,
C, 58.45; H, 4.23; N, 15.29.
3
OCH
(
(
3
), 4.76 (s, 2H, NHCH
d, J = 8.2Hz, 2H, H3′, H5′), 6.96 (s, 1H, isoxazole), 7.26
d, J = 8.2 Hz, 2H, H , H ), 7.48–7.50 (m, 3H, Ph), 7.58 (bs, 2H,
2
), 5.48 (s, 2H, CH
2
), 6.91
N-((1-Benzyl-1H-1,2,3-triazol-4-yl)methyl)-5-(4-chlorophenyl)
isoxazole-3-carboxamide (7i). Off-white crystals; yield: 75%; mp
À1
225–227 °C. IR (KBr, cm ) υ: 3371, 3111, 3064, 2923, 2853,
2′
6′
1
3
1
triazole, NH), 7.78–7.80 (m, 2H, Ph); C-NMR (100 MHz,
CDCl ) δ ppm: 35.0, 53.8, 55.3, 99.0, 114.5, 122.0, 125.9, 126.3,
26.7, 129.1, 129.8, 130.8, 144.3, 158.8, 159.0, 160.0, 171.6;
1667, 1612, 1538; H-NMR (500 MHz, CDCl3)
δ
ppm:
3
4.71 (d, J = 4.6 Hz, 2H, NHCH
2
), 5.53 (s, 2H, CH
2
), 6.94
1
(s, 1H, isoxazole), 7.28–7.30 (dd, J = 7.4, 1.9 Hz, 2H, Ph),
7.37–7.41 (m, 3H, Ph), 7.43 (bs, 1H, NH), 7.47 (d, J = 8.5 Hz,
2H, H , H ), 7.54 (s, 1H, triazole), 7.73 (d, J = 8.5 Hz, 2H,
+.
MS (m/z): 389 ([M] , 45), 307 (45), 215 (18), 188 (34), 173 (40),
21 (100), 105 (34), 77 (37); Anal. Calcd for C H N O :
1
21
19
5
3
2′
6′
1
3
C, 64.77; H, 4.92; N, 17.98. Found: C, 64.59; H, 5.17; N, 18.22.
H , H ); C-NMR (100 MHz, DMSO-d ) δ ppm: 35.0, 53.2,
3′ 5′ 6
N-((1-(4-Fluorobenzyl)-1H-1,2,3-triazol-4-yl)methyl)-5-
100.3, 123.6, 126.2, 126.7, 128.5, 128.6, 129.2, 129.8, 131.3,
+
.
phenylisoxazole-3-carboxamide (7d). White crystals; yield: 71%;
136.6, 145.1, 158.9, 159.9, 170.8; MS (m/z): 395 ([M] + 2,
À1
+.
mp 202–205 °C. IR (KBr, cm ) υ: 3360, 3113, 3065, 2923,
15), 393 ([M] , 46), 268 (10), 240 (25), 221 (17), 192 (28),
1
2
4
7
7
853, 1669, 1606, 1537; H-NMR (500MHz, CDCl ) δ ppm:
172 (41), 125 (100), 105 (51), 89 (35); Anal. Calcd for
3
.78 (s, 2H, NHCH ), 5.51 (s, 2H, CH ), 6.95 (s, 1H, isoxazole),
C H ClN O : C, 61.00; H, 4.10; N, 17.78. Found: C, 61.17;
2
2
20 16
5 2
.08 (t, J = 8.3 Hz, 2H, H3′, H5′), 7.28–7.31 (m, 2H, H2′, H6′),
.49–7.50 (m, 4H, Ph, NH), 7.56 (s, 1H, triazole), 7.79–7.81
H, 4.29; N, 17.90.
5-(4-Chlorophenyl)-N-((1-(4-methoxybenzyl)-1H-1,2,3-
triazol-4-yl)methyl)isoxazole-3-carboxamide (7j). Off-white crystals;
(
m, 2H, Ph); Anal. Calcd for C20
N, 18.56. Found: C, 63.50; H, 4.39; N, 18.73.
-(3,4-Dimethoxyphenyl)-N-((1-(4-methylbenzyl)-1H-1,2,3-
triazol-4-yl)methyl)isoxazole-3-carboxamide (7e). Off-white
5 2
H16FN O : C, 63.65; H, 4.27;
À1
yield: 61%; mp 224–227 °C. IR (KBr, cm ) υ: 3416, 3120,
1
5
2925, 2854, 1669, 1612, 1543; H-NMR (500 MHz, CDCl3)
δ ppm: 3.81 (s, 3H, OCH
5.46 (s, 2H, CH ), 6.90 (d, J = 8.4 Hz, 2H, H3′, H5′), 6.94 (s, 1H,
isoxazole), 7.25 (d, J = 8.4 Hz, 2H, H , H ), 7.37 (bs, 1H, NH),
3 2
), 4.72 (d, J = 5.9 Hz, 2H, NHCH ),
À1
crystals; yield: 55%; mp 169–172 °C. IR (KBr, cm ) υ: 3375,
2
1
3
134, 3061, 2960, 1668, 1609, 1541; H-NMR (500 MHz,
2′
6′
CDCl ) δ ppm: 2.35 (s, 3H, CH ), 3.95 (s, 3H, OCH ), 3.96
7.47–7.49 (m, 3H, triazole, H , H ), 7.73 (d, J = 8.5 Hz, 2H, H ,
3
3
3
2″
6″
3″
(
6
(
(
s, 3H, OCH
.84 (s, 1H, isoxazole), 6.95 (d, J= 8.4 Hz, 1H, H5″), 7.17–7.19
m, 4H, H2′, H3′, H5′, H6′), 7.28 (d, J=2.0Hz, 1H, H2″), 7.37
dd, J= 8.4, 2.0 Hz, 1H, H ), 7.45 (t, J= 5.8 Hz, 1H, NH), 7.50
3
) 4.71 (d, J= 5.8 Hz, 2H, NHCH
2
), 5.47 (s, 2H, CH
2
),
H
5″); Anal. Calcd for C21
H
18ClN
5
O
3
: C, 59.51; H, 4.28; N, 16.52.
Found: C, 59.23; H, 4.55; N, 16.33.
5-(4-Chlorophenyl)-N-((1-(4-fluorobenzyl)-1H-1,2,3-triazol-
4-yl)methyl)isoxazole-3-carboxamide (7k). White crystals; yield:
71%; mp 219–221°C. IR (KBr, cm ) υ: 3458, 3109, 1668,
1608, 1539; H-NMR (500 MHz, CDCl
6″
À1
(s, 1H, triazole); Anal. Calcd for C H N O : C, 63.73; H, 5.35;
23 23 5 4
1
N, 16.16. Found: C, 63.87; H, 5.14; N, 15.97.
-(3,4-Dimethoxyphenyl)-N-((1-(4-methoxybenzyl)-1H-1,2,3-
3
)
δ
ppm: 4.73
5
(d, J = 5.9 Hz, 2H, NHCH
2
), 5.50 (s, 2H, CH
2
), 6.94 (s, 1H,
triazol-4-yl)methyl)isoxazole-3-carboxamide (7f). White crystals;
isoxazole), 7.08 (t, J = 8.6 Hz, 2H, H3′, H5′), 7.28–7.30 (m, 2H,
H , H ), 7.40 (t, J = 5.9 Hz, 1H, NH), 7.48 (d, J = 8.5 Hz, 2H,
À1
yield: 63%; mp 159–161°C. IR (KBr, cm ) υ: 3408, 3116,
2′
6′
1
2
3
4
924, 1667, 1611, 1546; H-NMR (500MHz, CDCl ) δ ppm:
H , H ), 7.52 (s, 1H, triazole), 7.73 (d, J = 8.5 Hz, 2H, H , H );
3
2″ 6″ 3″ 5″
.81 (s, 3H, OCH
3
), 3.95 (s, 3H, OCH
.73 (d, J = 4.9 Hz, 2H, NHCH
3
), 3.97 (s, 3H, OCH
3
),
5 2
Anal. Calcd for C20H15ClFN O : C, 58.33; H, 3.67; N, 17.01.
Found: C, 58.14; H, 3.84; N, 16.87.
2 2
), 5.46 (s, 2H, CH ), 6.84 (s, 1H,
isoxazole), 6.91 (d, J = 8.6 Hz, 2H, H3′, H5′), 6.96 (d, J = 8.4 Hz,
N-((1-(4-Chlorobenzyl)-1H-1,2,3-triazol-4-yl)methyl)-5-(4-
1
1
7
H, H ), 725 (d, J = 8.6Hz, 2H, H , H ), 7.29 (d, J = 1.9 Hz,
chlorophenyl)isoxazole-3-carboxamide (7l).
Cream crystals;
5″
2′
6′
À1
H, H ), 7.38 (dd, J = 8.4 Hz, 1H, H ), 7.44 (bs, 1H, NH),
yield: 78%; mp 217–219 °C. IR (KBr, cm ) υ: 3369, 3116,
2″
6″
1
23 5 5
.51(s, 1H, triazole); Anal. Calcd for C23H N O : C, 61.46;
3064, 2946, 2854, 1668, 1608, 1542; H-NMR (500 MHz,
H, 5.16; N, 15.58. Found: C, 61.22; H, 4.91; N, 15.32.
-(3,4-Dimethoxyphenyl)-N-((1-(4-fluorobenzyl)-1H-1,2,3-
CDCl
3 2 2
) δ ppm: 4.73 (s, 2H, NHCH ), 5.49 (s, 2H, CH ), 6.93
5
(s, 1H, isoxazole), 7.22 (d, J = 7.90 Hz, 2H, H , H ), 7.35
2′
6′
triazol-4-yl)methyl)isoxazole-3-carboxamide (7g). Off-white crystals;
(d, J= 7.90 Hz, 2H, H , H ), 7.41 (bs, 1H, NH), 7.47 (d,
3’ 5′
À1
yield: 68%; mp 159–162 °C. IR (KBr, cm ) υ: 3456, 3129, 2927,
J= 8.4 Hz, 2H, H2″, H6″), 7.53 (s, 1H, triazole), 7.72 (d, J=8.4Hz,
2H, H3″, H5″); Anal. Calcd for C20 15Cl : C, 56.09; H, 3.53;
N, 16.35. Found: C, 55.86; H, 3.29; N, 16.18.
Biology. Reagents and chemicals. RPMI 1640 and fetal
1
2
(
844, 1668, 1607, 1577; H-NMR (500 MHz, CDCl
3
) δ ppm: 3.95
), 4.73 (d, J= 5.9 Hz, 2H,
NHCH ), 5.50 (s, 2H, CH ), 6.84 (s, 1H, isoxazole), 6.95
H
2 5 2
N O
3 3
s, 3H, OCH ), 3.97 (s, 3H, OCH
2
2
(
d, J= 8.4 Hz, 1H, H ), 7.08 (t, J= 8.2 Hz, 2H, H , H ), 7.28–7.30
bovine serum were purchased from Gibco BRL (Grand Island,
NY). 3-(4,5-Dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide
(MTT), trypsin-EDTA solution, and dimethyl sulfoxide (DMSO)
were obtained from Sigma (Saint Louis, MO, USA). Penicillin/
streptomycin was purchased from Invitrogen (San Diego, CA, USA).
Cell lines and cell culture. Human breast cancer cell lines
including MCF-7 and T-47D cells were obtained from the
National Cell Bank of Iran, Pasteur Institute, Tehran, Iran. Cancer
cell lines were grown in RPMI-1640 medium supplemented with
5″
3′
5′
(
m, 3H, H2′, H6′, H2″), 7.38 (d, J=8.4Hz, 1H, H6″), 7.40 (bs, 1H,
NH), 7.53 (s, 1H, triazole); Anal. Calcd for C22 20FN : C, 60.41;
H, 4.61; N, 16.01. Found: C, 60.23; H, 4.80; N, 15.86.
H
5 4
O
N-((1-(4-Chlorobenzyl)-1H-1,2,3-triazol-4-yl)methyl)-5-(3,4-
dimethoxyphenyl)isoxazole-3-carboxamide (7h). Off-white crystals;
yield: 68%; mp 202–205 °C. IR (KBr, cm ) υ: 3319, 2956,
2
3
À1
1
837, 1669, 1609, 1551; H-NMR (500MHz, CDCl
3
) δ ppm:
3 3
.95 (s, 3H, OCH ), 3.96 (s, 3H, OCH ), 4.71 (d, J = 5.9 Hz, 2H,
Journal of Heterocyclic Chemistry
DOI 10.1002/jhet

Month 2014
Triazole-Isoxazoles
1
0% heat-inactivated fetal calf serum, 1% L-Glutamine, 100μg/mL
streptomycin, and 100 U/mL penicillin and then incubated at 37°C
under a 5% concentration of CO
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the research council of Tehran University of Medical Sciences
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Journal of Heterocyclic Chemistry
DOI 10.1002/jhet