Recyclable bimetallic CuFe2O4 nanoparticles: An efficient catalyst for one-pot three-component synthesis of novel dicyanomethyl-2-oxoindolin-3-ylthiocarboxylic acids in a green solvent

Article abstract of DOI:10.1007/s00706-014-1159-z

A highly efficient and green synthesis of novel, potentially medicinally important oxindole derivatives has been developed using a fully recoverable heterogeneous copper ferrite nanocatalyst in water as a green solvent. The catalyst is magnetically separable and recyclable up to the fourth run without significant loss of activity. The products were obtained in high yields and purities via an easy workup procedure. Graphical abstract: [Figure not available: see fulltext.]

Full text of DOI:10.1007/s00706-014-1159-z

Monatsh Chem
DOI 10.1007/s00706-014-1159-z
ORIGINAL PAPER
Recyclable bimetallic CuFe2O4 nanoparticles: an efficient catalyst
for one-pot three-component synthesis of novel dicyanomethyl-2-
oxoindolin-3-ylthiocarboxylic acids in a green solvent
•
Ghazaleh Imani Shakibaei Ramin Ghahremanzadeh
•
Ayoob Bazgir
Received: 10 July 2013 / Accepted: 16 January 2014
Ó Springer-Verlag Wien 2014
Abstract A highly efficient and green synthesis of novel,
potentially medicinally important oxindole derivatives has
been developed using a fully recoverable heterogeneous
copper ferrite nanocatalyst in water as a green solvent. The
catalyst is magnetically separable and recyclable up to the
fourth run without significant loss of activity. The products
were obtained in high yields and purities via an easy
workup procedure.
convergency [5, 6]. MCRs have attracted widespread
attention in recent years, particularly in a green chemistry
context [7], as they typically proceed in the presence of a
catalyst and with excellent atom and bond economy [8, 9].
Owing to synthetic efficiency, the simplicity of the reaction
conditions, the wide range of readily available starting
materials, the simplicity of the one-pot procedure without
the need for isolation of intermediates and prevention of
tedious steps of protection and deprotection of functional
groups, as well as delivering molecular diversity, MCRs
have been extensively employed in the synthesis of het-
erocyclic compounds [10, 11].
Keywords Magnetic nanoparticles Á
Multicomponent reaction Á Green chemistry Á
Nanochemistry Á Heterogeneous catalysis
The application of such MCRs in the synthesis of ox-
indoles has been the subject of excellent reviews, on
account of the compounds’ unprecedented structural
diversity, biological activities, and incorporation in many
natural products [12, 13]. These include the dopamine
agonist ropinirole used for the treatment of Parkinson’s
disease, the anti-inflammatory tenidap, and the anticancer
kinase inhibitor sunitinib [14–16]. The C-3 functionalized
oxindoles are important scaffolds found in numerous nat-
ural products [17].
Introduction
The search for a highly efficient synthesis of multifunc-
tionalized elaborate molecules from simple reactants has
been an attractive objective in organic synthesis [1, 2]. By
offering opportunities for diversity-oriented synthesis from
three or more readily accessible precursors in a single
operation, multicomponent reactions (MCRs) have
emerged as a versatile tool to achieve this goal [3, 4]. The
pharmaceutical industry has fueled this resurgence because
of their ability to assemble combinatorial libraries of
complex and diverse structures for evaluation as lead
compounds in drug discovery by virtue of their intrinsic
In recent years, nanoparticles (NPs) have emerged as an
attracting class of catalysts, because of the increasing need
to develop low-cost, green, efficient, and reusable catalysts
[18–20]. Their nano-size property maximizes the contact
between reactants and the catalyst thus mimicking a het-
erogeneous catalyst, but recovery of these tiny NPs from
the reaction mixture is not possible by conventional
methods [21–23]. To address this issue, use of magnetically
separable catalysts is one of the most promising strategies
[24–26]. These systems combine the advantages of nano-
sized catalysts and magnetic properties thus providing the
opportunity for quantitative recovery of the catalyst by the
use of an external magnet, making it cost-effective and
G. I. Shakibaei Á A. Bazgir
Department of Chemistry, Shahid Beheshti University, General
Campus, 1983963113 Tehran, Iran
R. Ghahremanzadeh (&)
Nanobiotechnology Research Center, Avicenna Research
Institute, ACECR, Tehran, Iran
e-mail: r.ghahremanzadeh@yahoo.com
123

G. I. Shakibaei et al.
Scheme 1
potentially applicable for industrial applications [27, 28].
In this regard, iron-based materials, which benefit from
their terrestrial abundance and low toxicity, have been
extensively exploited as catalysts in many organic trans-
formations. Other simple magnetic NPs have expanded the
scope of such systems. Copper ferrite (CuFe2O4) NPs are
inexpensive, air-stable, magnetically separable, and eco-
nomical catalysts [29]. These spinel-type bimetal oxides
shown great potential in the catalysis field, although they
have so far been less investigated [30, 31].
absence of any catalyst, the reaction did not occur even
with prolonged reaction time (6 h, entry 16). To optimize
the catalyst amount we also performed the reaction with
different catalyst loadings (entries 9, 17, 18). Increasing
catalyst amount slightly changed the reaction rate and yield
(entry 18).
CuFe2O4 NPs were prepared by the co-precipitation
method at reduced temperatures [38]. The X-ray diffraction
(XRD) patterns of calcinated precipitate indicate that the
powder is mainly composed of CuFe2O4 and the average
diameter of the NPs was determined to be 30–40 nm by the
Scherrer equation (Fig. 1). Formation of copper ferrite NPs
was ascertained by scanning electron microscopy (SEM).
The SEM image in Fig. 2 shows that copper ferrite NPs
have a mean diameter of about 30–35 nm and a nearly
spherical shape.
As a part of our ongoing research [32–37], we herein
describe the use of CuFe2O4 NPs as a magnetically sepa-
rable catalyst in a three-component method for the
preparation of novel oxindole derivatives in water
(Scheme 1).
With optimized conditions in hand, then we turned our
attention to the scope and limitations of this process. A
variety of isatins 1, bearing either electron-withdrawing
groups (such as halide, nitro) or electron-donating groups
(such as alkyl group), were subjected to reaction with
thiocarboxylic acids 2 and malononitrile 3 to obtain a range
of dicyanomethyl-2-oxoindoline thiocarboxylic acids 4.
Pleasingly, all reactions gave high yields (60–89 %,
Table 2).
Results and discussion
In our initial studies, to standardize the proposed trans-
formation, a series of experiments were designed varying
reaction parameters including solvent, temperature, time,
catalyst type, and catalyst amount for the model reaction of
indoline-2,3-dione (1a, 1 mmol), 2-sulfanylacetic acid (2a,
1 mmol), and propanedinitrile (3) to furnish 2-[3-(dicy-
anomethyl)-2-oxoindolin-3-ylthio]acetic
acid
(4)
Having established the scope and limitations of this
reaction, we sought to briefly investigate the feasibility of
the reaction with other thiol nucleophiles. Unfortunately,
with other tested aromatic and aliphatic thiols, such as
thiophenol, thioethanol, and 11-mercaptoundecanoic acid,
TLC of the reaction mixture showed a combination of
starting materials and numerous products and the yield of
the desired product was very poor.
(Table 1). In the first phase, the effect of catalyst type was
investigated. As can be seen in Table 1 (entries 1–9),
among different catalysts, CuFe2O4 was found to provide
the best yield. Then, we probed the feasibility of this
reaction in various solvents which led us to choose water as
the solvent in view of both reaction time and yield (entries
9–13). Lowering the reaction temperature decreased the
reaction yield dramatically and only a trace amount of the
related product could be isolated (entries 14, 15). In the
The reusability of the inexpensive magnetically sepa-
rable nano copper ferrite catalyst was examined (Fig. 3).
123

Recyclable bimetallic CuFe2O4 nanoparticles
Table 1 Optimization of reaction conditions
Entry
Catalyst
Solvent
T/°C
Catalyst loading/mol%
Time/h
Yield/%a
1
CH3CO2H
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
H2O
MeOH
EtOH
THF
CH2Cl2
H2O
H2O
H2O
H2O
H2O
90
90
90
90
90
90
90
90
90
50
70
50
50
r.t.
50
90
90
90
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
10
5
5
5
5
5
5
5
5
5
3
5
5
5
5
3
3
6
4
5
-
2
SSA
-
3
p-TSA
-
4
Alum
-
5
Nano MgO
Nano SnO2
Nano Fe3O4
Nano MnFe2O4
Nano CuFe2O4
Nano CuFe2O4
Nano CuFe2O4
Nano CuFe2O4
Nano CuFe2O4
Nano CuFe2O4
Nano CuFe2O4
-
48
51
-
6
7
8
57
86
55
65
-
9
10
11
12
13
14
15
16
17
18
a
-
-
45
-
Nano CuFe2O4
Nano CuFe2O4
76
89
15
Isolated yield
The catalyst was magnetically separated from the reaction
mixture after completion of the reaction, washed with
ethanol, and used directly for the further runs.
which are often incorporated in pharmacologically active
compounds. Prominent advantages of this protocol include
using inexpensive reagents, easy workup, high product
yields, conducting the reaction in water, and the fully mag-
netic recoverability of the catalyst, making it a green method.
A plausible mechanism for the formation of 4a is pro-
posed in Scheme 2. It is reasonable to assume that 4a
results from initial formation of 5a by standard Knoeve-
nagel condensation of the malononitrile 3 and isatin 1a.
Then, the subsequent Michael-type addition of the 2-mer-
captoacetic acid 2a to 5 affords the corresponding product
4a (Scheme 2). Mechanistically, we believed this reaction
to proceed through an intermediate 5a. As a means to
support our mechanistic hypothesis, we prepared and iso-
lated the isatylidenemalononitrile 5a. Starting from 5a in
the same reaction conditions, we similarly obtained the
desired product 4a (Scheme 3).
Experimental
Melting points were measured on an Electrothermal 9100
1
apparatus. H and 13C NMR spectra were recorded on a
Bruker DRX-300 AVANCE spectrometer at 300.13 and
75.47 MHz, respectively. Spectra were obtained in solu-
tions of DMSO-d6 using TMS as internal standard. IR
spectra were recorded using an FTIR apparatus. Elemental
analyses were performed using a Heracus CHN-O-Rapid
analyzer. The nanocatalyst was determined using a KYKY
EM-3200 scanning electron microscope operated at an
accelerating voltage of 26 kV. The chemicals used in this
work were obtained from Fluka and Merck and were used
without purification.
Conclusion
We have developed copper ferrite NPs as an efficient nan-
ocatalyst for the synthesis of novel oxindole derivatives
123

G. I. Shakibaei et al.
Fig. 1 XRD patterns of calcinated CuFe2O4
kept in a furnace at 800 °C at a heating rate of 2 °C/min
and cooled to 100 °C at 5 °C/min in air.
Typical procedure for the preparation of 2-[3-
(dicyanomethyl)-2-oxoindolin-3-ylthio]acetic acid
(4a, C13H9N3O3S)
A mixture of 0.14 g 1a (1 mmol), 0.22 cm3 2a (1 mmol),
0.06 g 3 (1 mmol), and 0.024 g of CuFe2O4 (10 mol%) in
5 cm3 H2O was heated at 90 °C for 3 h. After completion
of the reaction, indicated by TLC (ethyl acetate/n-hexane
1:1), the catalyst was magnetically removed from the
mixture and washed several times with EtOH. Then the
residue was filtered and the precipitate was washed with
diethyl ether (2 9 5 cm3) to afford 0.246 g of pure 4a as
Fig. 2 SEM image of CuFe2O4
1
light pink powder (86 %). M.p.: 267 °C (dec); H NMR
Preparation of catalyst
(300 MHz, DMSO-d6): d = 4.05–4.13 (2H, m, CH2), 4.81
(1H, s, CH), 6.85–7.27 (4H, m, H–Ar), 10.64 (1H, s, NH),
12.15 (1H, s, COOH) ppm; 13C NMR (75 MHz, DMSO-
d6): d = 34.0, 46.1, 77.6, 110.2, 117.7, 122.5, 125.1, 127.2,
CuFe2O4 NPs were prepared by co-precipitation of
Cu(NO3)2 and Fe(NO3)3 in water in the presence of sodium
hydroxide. Briefly, to a solution of Fe(NO3)3Á9H2O
(0.05 mol) and Cu(NO3)2Á3H2O (0.025 mol) in 100 cm3 of
distilled water, 75 cm3 of 4 M NaOH was added at room
temperature over a period of 10 min to form a reddish-
black precipitate. Then the reaction mixture was warmed to
90 °C and stirred. After 2 h, it was cooled to room tem-
perature and the formed magnetic particles were separated
by a magnetic separator. Then, the catalyst was washed
with water and kept in air in an oven overnight at 80 °C.
Then the catalyst was ground in a mortar and pestle and
129.3, 142.9, 157.9, 175.0, 175.7 ppm; IR (KBr):
-1
ꢀ
m = 3,273, 3,160, 2,196, 1,759, 1,600 cm
.
2-[5-Bromo-3-(dicyanomethyl)-2-oxoindolin-3-ylthio]ace-
tic acid (4b, C13H8BrN3O3S)
1
Light gray powder (82 %); m.p.: 260 °C (dec); H NMR
(300 MHz, DMSO-d6): d = 4.04–4.18 (2H, m, CH2), 4.85
(1H, s, CH), 6.81–7.42 (3H, m, H–Ar), 10.78 (1H, s, NH),
12.13 (1H, s, COOH) ppm; 13C NMR (75 MHz, DMSO-
d6): d = 34.1, 46.1, 76.7, 112.2, 114.1, 117.7, 127.9, 129.7,
123

Recyclable bimetallic CuFe2O4 nanoparticles
Table 2 CuFe2O4-catalyzed reaction of isatin, thioacids, and malononitrile
Product
X
R1
R2
Yield/%a
M.p./°C
4a
4b
4c
4d
4e
4f
4g
4h
4i
H
H
H
86
82
89
75
72
65
60
68
85
64
69
65
267 (dec)
260 (dec)
260 (dec)
255–258
249–252
239 (dec)
245–248
262 (dec)
250 (dec)
232–235
237 (dec)
246 (dec)
Br
NO2
H
H
H
H
H
Me
H
H
Me
H
H
Bz
H
H
H
Me
Me
Me
Me
Me
Me
Br
NO2
H
H
H
4j
4k
4l
Me
H
Me
H
Bz
a
Isolated yield
132.0, 142.3, 158.6, 175.0, 175.2 ppm; IR (KBr):
-1
ꢀ
m = 3,376, 3,277, 2,205, 1,730, 1,599 cm
.
2-[3-(Dicyanomethyl)-5-nitro-2-oxoindolin-3-ylthio]acetic
acid (4c, C13H8N4O5S)
Cream powder (89 %); m.p.: 260 °C (dec); 1H NMR
(300 MHz, DMSO-d6): d = 4.07–4.20 (2H, m, CH2), 4.98
(1H, s, CH), 7.08 (1H, d, 3JH-H = 8.5 Hz, H–Ar), 8.13 (1H,
3
s, H–Ar), 8.24 (1H, d, JH-H = 8.7 Hz, H–Ar), 11.37 (1H,
s, NH), 12.24 (1H, s, COOH) ppm;13C NMR (75 MHz,
DMSO-d6): d = 34.2, 45.9, 75.8, 110.5, 117.5, 120.9,
126.7, 128.3, 142.9, 149.4, 159.4, 175.1, 176.1 ppm; IR
ꢀ
(KBr):m = 3,318, 3,159, 2,200, 1,719, 1,613, 1,505,
1,362 cm-1
.
Fig. 3 Recyclability of the catalyst. 1 (1 mmol), 2 (1 mmol), 3
(1 mmol), and CuFe2O4 (10 mol%) in 5 cm3 H2O were heated at
90 °C for 3 h
2-[3-(Dicyanomethyl)-1-methyl-2-oxoindolin-3-ylthio]ace-
tic acid (4d, C14H11N3O3S)
Cream powder (75 %); m.p.: 255–258 °C; 1H NMR
(300 MHz, DMSO-d6): d = 3.16 (3H, s, CH3), 4.06–4.14
(2H, m, CH2), 4.88 (1H, s, CH), 7.05–7.38 (4H, m, H–Ar),
12.21 (1H, s, COOH) ppm;13C NMR (75 MHz, DMSO-
d6): d = 30.5, 34.6, 47.2, 78.8, 111.0, 118.5, 122.9, 125.8,
2-[3-(Dicyanomethyl)-5-methyl-2-oxoindolin-3-ylthio]ace-
tic acid (4e, C14H11N3O3S)
1
Cream powder (72 %); m.p.: 249–252 °C (dec); H NMR
(300 MHz, DMSO-d6): d = 2.25 (3H, s, CH3), 4.05–4.18
(2H, m, CH2), 4.77 (1H, s, CH), 6.07–6.76 (1H, m, H–Ar),
127.7, 130.0, 143.4, 158.2, 175.2, 175.8 ppm; IR (KBr):
-1
ꢀ
m = 3,172, 2,193, 1,733, 1,683 cm
.
123

G. I. Shakibaei et al.
Scheme 2
Scheme 3
7.00–7.05 (2H, m, H–Ar), 10.53 (1H, s, NH), 12.14 (1H, s,
COOH) ppm; 13C NMR (75 MHz, DMSO-d6): d = 23.5,
34.2, 47.0, 78.5, 110.8, 118.3, 123.2, 126.1, 127.5, 129.2,
2-[5-Bromo-3-(dicyanomethyl)-2-oxoindolin-3-
ylthio]propanoic acid (4h, C14H10BrN3O3S)
1
Light gray powder (68 %); m.p.: 262 °C (dec); H NMR
3
ꢀ
143.0, 157.8, 175.0, 175.4 ppm; IR (KBr): m = 3,203,
(300 MHz, DMSO-d6): d = 1.54 (3H, d, JH-H = 7.1 Hz,
3,078, 2,194, 1,716, 1,602 cm-1
.
CH3), 4.37–4.45 (1H, m, CH), 4.83 (1H, s, CH(CN)2),
6.79–6.82 (1H, m, H–Ar), 7.40–7.46 (2H, m, H–Ar), 10.76
(1H, s, NH), 12.10 (1H, s, COOH) ppm;13C NMR
(75 MHz, DMSO-d6): d = 23.1, 34.5, 46.4, 77.4, 112.5,
114.5, 118.0, 128.3, 129.7, 132.0, 142.5, 160.0, 175.5,
2-[1-Benzyl-3-(dicyanomethyl)-2-oxoindolin-3-ylthio]ace-
tic acid (4f, C20H15N3O3S)
Cream powder (65 %); m.p.: 239 °C (dec); 1H NMR
(300 MHz, DMSO-d6): d = 4.08-4.21 (2H, m, SCH2),
4.88 (1H, s, CH), 4.94-5.02 (2H, m, CH2Ph), 6.88-7.08
(3H, m, H–Ar), 7.23-7.30 (6H, m, H–Ar), 12.23 (1H, s,
COOH) ppm; owing to very low solubility of the product
4f, we cannot report the 13C NMR data for this product; IR
ꢀ
175.7 ppm; IR (KBr): m = 3,294, 3,160, 2,209, 1,718,
1,678 cm-1
.
2-[3-(Dicyanomethyl)-5-nitro-2-oxoindolin-3-ylthio]prop-
anoic acid (4i, C14H10N4O5S)
ꢀ
(KBr): m = 3,096, 2,837, 2,208, 1,726, 1,650, 1,612, 1,545,
Cream powder (85 %); m.p.: 250 °C (dec); 1H NMR
(300 MHz, DMSO-d6): d = 1.56 (3H, bs, CH3), 4.42–4.44
(1H, m, SCH), 4.97 (1H, s, CH(CN)2), 7.03 (1H, bs, H–Ar),
8.11–8.20 (2H, m, H–Ar), 11.36 (1H, s, NH), 12.21 (1H, s,
COOH) ppm; 13C NMR (75 MHz, DMSO-d6): d = 23.5,
34.8, 46.9, 77.6, 112.8, 114.7, 118.6, 128.8, 130.2, 132.6,
1,374 cm-1
.
2-[3-(Dicyanomethyl)-2-oxoindolin-3-ylthio]propanoic
acid (4g, C14H11N3O3S)
1
Light gray powder (60 %); m.p.: 245-248 °C; H NMR
(300 MHz, DMSO-d6): d = 1.55 (3H, d, JH-H = 9.3 Hz,
3
ꢀ
143.2, 160.4, 175.9, 176.4 ppm; IR (KBr): m = 3,291,
CH3), 4.43–4.48 (1H, m, SCH), 4.81 (1H, s, CH(CN)2),
6.85–6.87 (1H, m, H–Ar), 6.97–7.02 (1H, m, H–Ar),
7.17–7.26 (2H, m, H–Ar), 10.64 (1H, s, NH), 12.14 (1H, s,
COOH) ppm;13C NMR (75 MHz, DMSO-d6): d = 22.6,
34.3, 46.0, 77.1, 112.2, 114.0, 117.6, 128.0, 129.4, 131.5,
3,086, 2,193, 1,730, 1,609 cm-1
.
2-[3-(Dicyanomethyl)-1-methyl-2-oxoindolin-3-
ylthio]propanoic acid (4j, C15H13N3O3S)
1
Light gray powder (64 %); m.p.: 232–235 °C; H NMR
(300 MHz, DMSO-d6): d = 1.58 (3H, d, JH-H = 7.5 Hz,
CH3), 3.18 (3H, s, CH3), 4.43–4.50 (1H, m, CH2), 4.79
3
ꢀ
141.9, 159.3, 175.1, 175.4 ppm; IR (KBr): m = 3,280,
3,158, 2,200, 1,723, 1,682 cm-1
.
123

Recyclable bimetallic CuFe2O4 nanoparticles
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(1H, m, H–Ar), 7.20–7.28 (2H, m, H–Ar), 12.17 (1H, s,
COOH) ppm;13C NMR (75 MHz, DMSO-d6): d = 22.4,
30.3, 34.0, 45.6, 76.7, 111.8, 113.3, 117.4, 127.6, 129.0,
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131.1, 141.3, 159.0, 174.8, 175.1 ppm; IR (KBr):
-1
ꢀ
m = 3,088, 2,198, 1,716, 1,675 cm
.
2-[3-(Dicyanomethyl)-5-methyl-2-oxoindolin-3-
ylthio]propanoic acid (4k, C15H13N3O3S)
Cream powder (69 %); m.p.: 237 °C (dec); 1H NMR
3
(300 MHz, DMSO-d6): d = 1.56 (3H, d, JH-H = 7.2 Hz,
CH3), 2.25 (3H, s, CH3), 4.41–4.48 (1H, m, SCH), 4.78
(1H, s, CH(CN)2), 6.73–6.76 (1H, m, H–Ar), 7.00–7.05
(2H, m, H–Ar), 10.53 (1H, s, NH), 12.13 (1H, s, COOH)
ppm;13C NMR (75 MHz, DMSO-d6): d = 22.4, 23.6, 34.2,
45.7, 76.4, 111.5, 113.0, 117.0, 127.2, 128.7, 130.8, 141.0,
ꢀ
158.8, 175.3, 175.6 ppm; IR (KBr): m = 3,283, 3,079,
2,200, 1,727, 1,675 cm-1
.
2-[1-Benzyl-3-(dicyanomethyl)-2-oxoindolin-3-
ylthio]propanoic acid (4l, C21H17N3O3S)
1
Light gray powder (65 %); m.p.: 246 °C (dec); H NMR
(300 MHz, DMSO-d6): d = 1.57 (3H, d, JH-H = 8.8 Hz,
3
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Chem 8:735
CH3), 4.40–4.46 (1H, m, SCH), 4.78 (1H, s, CH(CN)2),
4.90–4.98 (2H, m, CH2Ph), 6.81–6.85 (1H, m, H–Ar),
6.99–7.05 (1H, m, H–Ar), 7.20–7.28 (2H, m, H–Ar), 12.18
(1H, s, COOH) ppm; owing to very low solubility of the
`
29. Hudson R, Riviere A, Cirtiu CM, Luska KL, Moores A (2012)
Chem Commun 48:3360
product 4l, we cannot report the 13C NMR data for this
-1
ꢀ
product; IR (KBr):m = 3,081, 2,208, 1,723, 1,682 cm
.
30. Ishikawa S, Hudson R, Moores A, Li CJ (2012) Heterocycles
86:1023
31. Li B, Li M, Yao C, Shi Y, Ye D, Wu J, Zhao D (2013) J Mater
Chem A 1:6742
Acknowledgments We thank the Avicenna Research Institute and
Research Council of Shahid Beheshti University.
32. Imani Shakibaei G, Feiz A, Ghahremanzadeh R, Bazgir A (2010)
Chem Pharm Bull 58:896
33. Imani Shakibaei G, Samadi S, Ghahremanzadeh R, Bazgir A
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