Coordination-mediated radical nitration of methyl salicylate by ferric nitrate

Article abstract of DOI:10.14233/ajchem.2014.15819

Nitration of methyl salicylate was performed by ferric nitrate in refluxing ethyl acetate solution. A coordination-mediated radical nitration process was proposed based on the results of electronic absorption spectra, cyclic voltammetry and electrospray ionization mass spectra. It was the coordination of methyl salicylate with ferric nitrate that promoted the splitting of N-O bonds of nitrate group in ferric nitrate and resulted in the formation of nitro radicals, oxygen radicals and complex radicals. The nitro radicals reacted with methyl salicylate or its complexes with iron to give a series of nitration products and Fe(II) ions. Meanwhile, oxygen radicals hydrolyzed to hydroxide which precipitated free ferric ions to isolate solid ferric oxides.

Full text of DOI:10.14233/ajchem.2014.15819

Asian Journal of Chemistry; Vol. 26, No. 1 (2014), 241-246
http://dx.doi.org/10.14233/ajchem.2014.15819
Coordination-Mediated Radical Nitration of Methyl Salicylate by Ferric Nitrate
1
,2
1
1,2
1,2
1,2
2
YANZHU LIU , MINGMING ZU , XIUXIN ZOU , QING ZHENG , XIA LI , XUEZHEN ZHOU ,
1,3
1,3
1,2
1,2,3,*
QUN TANG , SHIHAN ZHANG , LING ZHANG and YONGXIU LI
1
2
3
Research Center for Rare Earths & Micro/Nano Functional Materials, Nanchang University, Nanchang 330031, P.R. China
Department of Chemistry, Nanchang University, Nanchang 330031, P.R. China
Institute of Advanced Study, Nanchang University, Nanchang 330031, P.R. China
*
Corresponding author: Fax: +86 791 83969240; Tel: +86 791 88305741; E-mail: yxli@ncu.edu.cn
Received: 23 May 2013; Accepted: 23 September 2013; Published online: 26 December 2013;
AJC-14514
Nitration of methyl salicylate was performed by ferric nitrate in refluxing ethyl acetate solution. A coordination-mediated radical nitration
process was proposed based on the results of electronic absorption spectra, cyclic voltammetry and electrospray ionization mass spectra.
It was the coordination of methyl salicylate with ferric nitrate that promoted the splitting of N-O bonds of nitrate group in ferric nitrate and
resulted in the formation of nitro radicals, oxygen radicals and complex radicals. The nitro radicals reacted with methyl salicylate or its
complexes with iron to give a series of nitration products and Fe(II) ions. Meanwhile, oxygen radicals hydrolyzed to hydroxide which
precipitated free ferric ions to isolate solid ferric oxides.
Keywords: Methyl salicylate, Ferric nitrate, Coordination, Radicals, Nitration.
Therefore, seeking new standpoints for the explanation of
nitration reaction process remains an important challenge for
INTRODUCTION
35
The industrially nitration requires the use of corrosive
chemists .
1
-9
liquid phase nitric acid and sulfuric acid mixture . Over the
past two decades, remarkable progress has been made in the
nitration reactions using metal nitrates as nitration agents or
co-catalysts for improving the nitration efficiency and reducing
Nitration is usually considered as an electrophilic
35
aromatic substitution reaction . With this idea, metal ions in a
nitration reaction have been suggested to play a catalytic role
+
2
to lead a higher concentration of NO
1,11-12
by an accentuation of
. However, the nitration
1
,10-23
the damage to the equipment and environment
. Particular
the Bronsted acidity of nitric acid
attention has also been directed to the nitration reactions of
drug or bio-molecules due to their significant roles in numerous
physiological processes ranged from regulation of cardio-
process using metal nitrates as nitrating reagents might not
available through nitronium ion in neutral or basic solution
because the formation of nitronium ion favors condition of
2
4-30
1,36
vascular function to memory formation
We have studied the facile nitration reaction of methyl
.
high acidity. Thus, radical mechanism was proposed . For
1
example, Cornelis and Laszlo proposed a plausible mecha-
salicylate with transition metal nitrates to afford the corres-
nism to explain the nitration of phenol by ferric nitrate based
2+
on the suggestion on the formation of nitro radical and Fe ,
31-34
ponding nitro compounds . In the cases of Fe(III) and Cu(II)
nitrates as nitration reagents, we observed the isolation of metal
oxides and hydroxides, which has allowed us to recover metal
materials by a simple filtration process. The regioselectivity
of nitration is significantly higher than that of general nitration
using nitric acid and sulfuric acid mixture as nitrating reagents.
For example, in the case of nitration of methyl salicylate with
ferric nitrate, the regioselectivity (P/O) presented by the ratio
of methyl 5-nitrosalicylate (P) to methyl 3-nitrosalicylate (O)
is up to 5.3. However, the molecular mechanism of this nitration
is still unclear. Moreover, the detail mechanism of nitration
occurred in neutral solution containing metal nitrates is obscure.
however, no direct evidence was provided and the explanation
is poor.
In this paper, we suggest a coordination-mediated radical
nitration of phenol by ferric nitrate because that ferric ions
show a typical coordination reaction toward phenol comp-
ounds. Therefore, by analyzing the electronic absorption spectra,
cyclic voltammetry and electrospray ionization mass spectra
of mixture solution of methyl salicylate and ferric nitrate, we
paid attention to demonstrate or identify the intermediates
formed during the nitration process of methyl salicylate with
ferric nitrate, including radicals and coordination compounds.

242 Liu et al.
Asian J. Chem.
It can be concluded that the nitration was indeed mediated by
the coordination between ferric nitrate and methyl salicylate.
And a novel coordination mediated radical nitration mechanism
was proposed to illustrate all the experimental results. This
mechanism provides promise not only for designing novel
nitration routes of valuable compounds, but also for under-
standing physiological efficacy of methyl salicylate, nitrate
group and iron ions in biological systems since they share the
FN : 6.75 g
MS: 5.8 mL
EA: 30 mL
Temp. 78 °C
0
2
4
min (A)
0 min (B)
0 min (C)
37
common components either in food or in pharmaceuticals .
EXPERIMENTAL
The ESIMS were determined on a Finnigan LCD mass
spectrometer; the concentration of the samples were about 1 µ
-1
mol dm . The diluted solutions were electrosprayed at a flow
-6
-3
-1
400
600
Wavelength (nm)
800
rate of 5 × 10 dm min with a needle voltage of +4.5 kv.
The mobile phase was methanol and the samples run in the
positive-ion mode. Cyclic voltammetry were performed in a
three-electrode system of a CHI660 electrochemical work-
Fig. 1 Electronic absorption spectra of mixture solution of methyl
salicylate and ferric nitrate in ethyl acetate; (a) at room temperature
(
0 min); (b) refluxing for 20 min; (c) refluxing for 40 min
3
station. Ethyl acetate and KNO used as solvent and supporting
electrolyte, Pt-C as working electrode, Ag/AgCl as reference
electrode,Pt as auxiliary electrode.
Nitration reaction of methyl salicylate and ferric
Cyclic voltammetry of the reaction solution of iron(III)
nitrate and methyl salicylate: To identify the role of coordi-
nation between methyl salicylate with ferric nitrate, cyclic
voltammetry method was applied. Fig. 2 shows the cyclic
voltammetry curves of different solutions. There are two oxi
dation-reduction peaks of pure ferric nitrate (Fig. 2a) in the
3 3 2
nitrate: Fe (NO ) ·9H O (A.R.) was dissolved in ethyl acetate
solution (A.R. 20 mL) in a 100 mL flask, then methyl salicylate
was added. The mixture solution was heated to reflux under
stirring with a magnetic stirrer. For a certain interval reaction
period, 0.2 mL reaction solution was taken out and diluted to
1
.2
1
0 mL with ethyl acetate for the electronic absorption spectra
(a)
characterization carried out by a Shimadzu UV3100 spectro-
photometer. Oxygen radicals were confirmed by hydroxyl-
amine oxidation in the reaction solution as ferric nitrate
reacted with methyl salicylate for 40 min at 90 °C. To this yellow
reaction solution, hydroxylamine hydrochloride, 4-hydroxy
benzenesulfonic acid and 1-naphthylamine were added.
0.8
-
1.097
0
0
.4
.0
-0.967
RESULTS AND DISCUSSION
The addition of methyl salicylate into ethyl acetate
solution containing ferric nitrate led to a typical red-violet
complex. Fig. 1 shows the electronic absorption spectra of
mixture solution of methyl salicylate and ferric nitrate as well
as their reaction solutions after refluxing different times. In
the electronic absorption spectra of mixture solution of ferric
nitrate and methyl salicylate shown in Fig. 1a, the broad
absorption band within 430 nm and 750 nm with maximum at
1
.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
Potential (V)
0.02
0.01
0.00
(
b)
-0.66
-
0.23
5
50 nm can be identified to the charge transfer band from the
HOMO of the phenol to the d -orbital of the iron atom, indi-
π
cating that methyl salicylate were coordinated to Fe(III) ions.
This broad absorption band was enhanced upon refluxing 20
min (Fig.1b) and was weakened with refluxing time prolon-
gation to 40 min (Fig. 1c), indicating that the formed coordina-
tion compounds are intermediates because their concentration
was increased at first with the increase of reaction temperature
and decreased at last with the formation of nitration products.
Finally, the red-violet solution became yellow and the intensity
of absorption peak at 550 nm decreased to near zero. These
facts demonstrated that the nitration of methyl salicylate by
ferric nitrate is mediated by the coordination between methyl
salicylate and ferric nitrate.
-
0.01
0
.35
-0.02
0
.8 0.6 0.4 0.2 0.0 -0.2 -0.4 -0.6 -0.8 -1.0
Potential (V)
Fig. 2 Cyclic voltammetry of different solutions (scan rate: 0.01V/s)
(
(
a) The solutin of ferric nitrate (dissolved in 0.1 mol/L KNO
b) The reaction solution of methyl salicylate and ferric
3
);
3
nitrate(dissolved in 0.1 mol/L KNO )

Vol. 26, No. 1 (2014)
Coordination-Mediated Radical Nitration of Methyl Salicylate by Ferric Nitrate 243
cyclic voltammetry curve of ferric nitrate solution due to the
oxidation-reduction of ferric-ferrous ions. These two oxidation-
reduction peaks also emerged in the cyclic voltammetry curve
of mixture solution of methyl salicylate and ferric nitrate
ferric nitrate as neutral or anion ligand to form a series of
complexes with molar ratio of 3:1, 2:1,1:1.
Compared to Fig. 4a, some new peaks, such as m/z = 315.8,
332, 348, 362, 377.7, 470.9, 486.4, 609.9, 666.9 can be
observed from the ESIMS of solution after refluxing 20 min
(Fig. 4b). At the same time, the relative intensity of peaks
identified to iron nitrates and their complexes with methyl
salicylate has been changed. For example, the relative intensity
of peaks corresponding to the complexes of ferric nitrate and
methyl salicylate with molar ratio of 1:1 was increased with
the decrease of relative intensity of peak to ferric nitrate. Mean-
while, the peaks corresponding to the complexes of ferric
nitrate and methyl salicylate with molar ratio of 1:2 were
vanished. These facts indicated that refluxing at high tempe-
rature is beneficial to the formation of complex with molar
ratio of ferric nitrate to methyl salicylate 1:1 rather than 1:2.
Furthermore, with refluxing time prolongation from 20 to 40 min
(Fig. 2b). However, the reduction potential is more positive
than those of ferric nitrate. This fact indicated that the forma-
tion of coordination complexes between methyl salicylate and
ferric nitrate can make the reduction reaction of ferric ion more
easily which can be further demonstrated by the formation of
2+
Fe . Addition of 1,10-phenanthroline into the resulting yellow
solution caused the yellow color changed to red immediately.
The wide band ranging from 400 to 550 nm in the electronic
absorption spectra (Fig. 3) indicated the existing of ferrous
ions which was reduced from ferric ions coordinated by
methyl salicylate.
2.5
2.0
1.5
1.0
0.5
0.0
(
Fig. 4c), the relative intensity of peaks corresponding to the
3
Fe +phen
+
2
Fe +phen
+
p ms
217.2
261.2
1
00
(
A)
90
80
70
60
50
40
30
20
10
0
3
58.2
RYS+ phen
534.7
89.5 532.1
3
8
03.6
610.9
683.7
741.8
507.3
866.9 979.9
RYS
00
200
400
600
m/z
800
1000
4
500
600
700
800
p ms
00
Wavelength (nm)
3
15.8
1
Fig. 3 Electronic absorption spectra of yellow reaction solutions (YRS)
with and without addition of 1,10- phenanthroline; showing the
existing of Fe(II) in yellow reaction solution
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
(B)
361.6
Evidence for the formation of complexes between
iron(III) nitrate and methyl salicylate by ESIMS study:
The main species or intermediates formed in the mixing solu-
tion of ferric nitrate with methyl salicylate before and after
refluxing can be evaluated from their ESIMS shown in Fig. 4.
There are four groups of peaks in the ESIMS of the mixture
solution of ferric nitrate and methyl salicylate at room tempe-
rature (Fig. 4a). The first group refers to iron nitrates, including
6
84.0
6
66.9
0 217.1261.2
0
0
0
470.9
77.7
609.9
3
7
59.7 906.7939.5
486.4
2
00
400
600
m/z
800 1000
p ms
100
+
+
217.1
[
Fe(NO
3
)
2
(H
2
O)
2
] (m/z = 217), [Fe(NO
3
)
3
H
3
O] (m/z = 261)
+
)] (m/z = 305). The second group includes
9
0
0
and [Fe(NO
3
)
3
(HNO
3
261.1
(C)
315.8
6
89.7
8
the complexes of ferric nitrate with methyl salicylate anion
+
70
60
(
[
3
denoted as MS-H), such as [Fe(MS-H)(NO )] (m/z = 269),
+
+
Fe(MS-H)
90). The third group is the complexes of ferric nitrate and
neutral methyl salicylate with molar ratios of 1:1, 1:2, 1:3,
2 2 3
] (m/z = 358) and [Fe(MS-H) CH OH] (m/z =
6
66.7
50
40
30
20
10
0
331.6
3
361.6
99.2
705.9
+
3
including [Fe(MS)(NO
3
)
2
] (m/z = 332), [Fe(NO
3
)
2
(MS)
2 3
CH
470.6
486.6
+
O)] (m/z = 532-534), [Fe(NO (MS) CH
+
609.9
709.8
892.9955.5
62.4
7
OH(H
2
3
)
2
3
OH(H O)]
3 2
5
96.7
m/z = 683.7-686). The last group relates to the dimer of ferric
nitrate and its complexes with methyl salicylate or MS-H, such
200
400
600
m/z
800
1000
+
+
as [Fe
10.9), [Fe
facts demonstrated that methyl salicylate can coordinate to
2
(NO
3
)
5
] (m/z = 422), [Fe
2 3
(NO )
5
(MS)(H
2
O)
2
] (m/z =
Fig. 4 ESIMS of mixture solution of methyl salicylate and ferric nitrate in
ethyl acetate; (a) at room temperature; (b) refluxing for 20 min; (c)
refluxing for 40 min
+
6
2
(MS-H) (NO (CH
2
3
)
5
3
OH)
2 2
(H O)] (804). These

244 Liu et al.
Asian J. Chem.
1
:1 complexes of ferric nitrate and methyl salicylate was also
2.5
B
decreased, indicating this complex formed previously has been
transferred to final nitration products.
0
0
0
.5
.4
.3
2
.0
In order to illustrate the nitration process via coordination
intermediates, we suggested that the key step of nitration
reaction was involved the splitting of O-N bonds in complexes
C
1
.5
0.2
.1
.0
3 3
such as Fe(MS)(NO ) and the liberating of radicals such as
0
1
.0
oxygen and nitro radicals. With this suggestion, most of the
new peaks appeared in the ESIMS of solution after refluxing
0
4
00
500
600
700
800
A
Wavelength (nm)
2
0 and 40 min can be assigned to the intermediates derived
0.5
C
from the 1:1 complexes of ferric nitrate and methyl salicylate
as following reactions:
0
.0
+
.
[
(NO3)2(MS)FeNO2 ] (378) + O
400
500
600
700
800
[
Fe(MS)(NO ) ]
3
+
.
3
[(NO ) (MS)FeON
3
]
(362)
+ 2O
2
Wavelength (nm)
+
.
[
(NO3)2(MS)FeO ] (348)
+
Fig. 5. Identification of oxygen radicals in yellow reaction solution (YRS)
of ferric nitrate reacting with methyl salicylate at 90 °C for 40 min
by hydroxylamine oxidation method; (a) YRS + 0.1 g hydroxyl-
amine hydrochloride. (b) YRS + 0.1 g 4-hydroxyl benzenesulfonic
acid and 0.05 g 1-naphthylamine; (c) YRS + 0.1 g 4-hydroxyl
benzenesulfonic acid, 0.05 g 1-naphthylamine and 0.1 g
hydroxylamine hydrochloride (diluted to 30 mL)
NO2
+
.
+
.
[
(NO3)2(MS)Fe] (332) + O
[(NO3)(MS)FeNO2] (316) +
O
With similar consideration, some other new peaks in
Fig. 4b and c can be identified to the intermediates derived
from the 1:2 and 1:3 complexes of ferric nitrate and methyl
salicylate by following reactions:
radical mechanism. As shown in Scheme-I, the mechanism
includes three main steps: coordination, N-O bond splitting
with radical formation, nitration followed by complex disasso-
ciation as well as hydrate ferric oxide isolation and Fe(II) release.
It was the coordination between ferric nitrate and methyl sali-
cylate that resulted in the formation of a series of complexes
with different molar ratios of ferric nitrate and methyl salicylate,
which was demonstrated by electronic absorption spectra and
ESIMS. The splitting of O-N bonds in ferric nitrate was facili-
tated by the coordination with methyl salicylate and led to the
liberation of nitro and oxygen radicals which have been iden-
tified by chemical method or explained using results of ESIMS,
nitration and the isolation of hydrated ferric oxide. The para-
regioselectivity data reported previously demonstrated that the
nitration was mainly occurred between nitro radicals and
methyl salicylate as well as the complexes of methyl salicylate
with ferric nitrate, because nitro radicals favors attaching to
the para position of phenolic hydroxide group when methyl
salicylate was coordinated with ferric nitrate because of the
steric hendance effect. If the nitration had occurred as an inner
sphere mechanism, e.g. the splitting of N-O bonds in complexes
had occurred synchronous with the nitration, the nitro group
should favor attaching to the ortho position of hydroxide group
in phenolic ring. Once the coordinated methyl salicylate was
nitrated, it would disassociate to iron ions and nitrated methyl
salicylates due to their weak coordination. Then, the iron ions
were hydrolyzed to hydrated iron oxide with few of nitrate
groups and complexes.
+
.
[
(NO
3
)(MS-H)
2
CH
3
OH(H
2
O)FeO ](m/z=486)+
NO
O
2
+
[
3 2 2 3 2
Fe(NO ) (MS-H) CH OH(H O)] (m/z=532)
+
.
[
(NO
3
)(MS-H)
2
CH
3
OH(H
2
O)Fe ] (m/z=470)
+
+
O)] (m/z=683.7)
+
[
Fe(NO
3
)
2
(MS-H)
3
CH
3
OH(H
2
+
O
.
[
(NO
3
)(MS-H)
3
CH
3
OH(H
2
O)FeNO
2
]
(m/z=667)
+
[
Fe
2
(MS-H)
2
(NO
3
)
4
(CH
3
OH)
2
(H
2
O)] (m/z=741.6)
+
[
2 2 3 5 3 2 2
Fe (MS-H) (NO ) (CH OH) (H O)] (m/z=804)
.
[
Fe
2
(NO
2
)(MS-H)
2
(NO
)
3 4
]+(m/z=706)
+
O
2 2 3 4
Fe (NO)(MS-H) (NO )
]+(m/z=690)
+
O
.
[
Identification of the oxygen radicals: The oxygen
radicals formed in above reactions have been confirmed by a
38
hydroxylamine oxidation method . As shown in Fig. 5, the
electronic absorption spectra of yellow reaction solution (YRS)
with 4-hydroxy benzenesulfonic acid, hydroxylamine hydro-
chloride and 1-naphthylamine shows two typical absorption
bands at 405 nm and 520 nm (Fig. 5c). The band at 402 nm is
attributed to the product formed by the reaction of 4-hydroxy
benzenesulfonic acid and 1-naphthylamine (Fig. 5b). The band
at 520 nm is owing to the red complex formed by the reaction
of 4-hydroxyl benzenesulfonic acid and 1-naphthylamine with
the oxidation product nitrite of hydroxylamine hydrochloride
by oxygen radicals, demonstrating the existing of oxygen
radicals in the reaction solution of ferric nitrate and methyl
salicylate. The release of oxygen radicals can also be demons-
trated by the isolation of yellow precipitate hydrate ferric
3
1
Conclusion
oxide during the nitration process of methyl salicylate with
ferric nitrate. It is known that the oxygen radicals can be
hydrolyzed to hydroxide which precipitated the unreduced
ferric ions to form hydrated ferric oxides.
In summary, a likely coordination-mediated radical
nitration mechanism has been proposed for explaining the
nitration using metal nitrates as nitrating reagents. The results
of electronic absorption spectra, cyclic voltammetry and
ESIMS of mixture solutions of ferric nitrate and methyl
salicylate with different reaction temperature and times have
Nitration mechanism via radicals: Based on the facts
above, the nitration reaction of methyl salicylate with ferric
nitrate can be considered to occur via a coordination-mediated

Vol. 26, No. 1 (2014)
Coordination-Mediated Radical Nitration of Methyl Salicylate by Ferric Nitrate 245
O
O
O
N
N
O
N
H
O
O
O
O
O
O
O
Fe
Coordination
H
O
O
O
O
N
O
+
Fe(NO3)3
O
N
O
O
O
O
Fe
O
O
or
Redox Activation
.
O
+
.
+
O
N
O
O
O
O
Fe
O
N
Fe
H
O
O
O
O
N
O
_
O
.
.
NO2
O
+
+
O
or
Nitration
O
O
N
O
Fe
H
O
O
O
N
O
O
FeO
N
O
O
O
O
O
or
NO2
NO2
comp x d sociat n
compl el ex di si sa ssoci ai ot ion
H
H
O
O
NO2
O
O
2
+
+
3
+
+
Fe
Fe
+
O
O
NO2
1
.
:
5.3
H
+
H
O
O
H
O
NO2
O
O
O
Nitration
.
+ NO2
+
O
O
O
NO2
:
1
5.3
.
-
.
O + H O
OH +
2
-OH
Fe(OH) (NO )] + HNO
3
[
Fe(NO ) + -OH
3
2
3
3
[
Fe(OH) (NO )] + H O
Fe(OH)3 + HNO3
2
3
2
.
2
Fe(OH)3
Fe O 3H O
3
2
2
Scheme-I: Coordination-mediated radical nitration process

246 Liu et al.
Asian J. Chem.
1
1
1
3. R.R. Bak and A.J. Smallridge, Tetrahedron Lett., 42, 6767 (2001).
4. R. Rajagopal and K.V. Srinivasan, Synth. Commun., 33, 961 (2003).
5. N. Iranpoor, H. Firouzabadi, M. AliZolfigol, Synth. Commun., 28, 2773
demonstrated the formation of complexes and radicals. It is
the coordination between methyl salicylate and Fe(III) ion that
initiates the formation of NO
2
and O radicals as well as coordi-
radicals react with
(
16. A.K. Bose, S.N. Ganguly, M.S. Manhas, S. Rao, J. Speck, U. Pekelny
1998).
nated methyl salicylate radical cation NO
2
and E. Pombo-Villars, Tetrahedron Lett., 47, 1885 (2006).
7. M.A. Zolfigol, E. Ghaemi, E. Madrakian, Synth. Commun., 30, 1689
2000).
methyl salicylate or coordinated methyl salicylate radical
cation through radical nitration substitution to form final
nitrated products.
1
(
1
1
2
2
2
8. S. Dinçtürk and J.H. Ridd, J. Chem. Soc. Perkin Trans. II, 961 (1982).
9. S. Dinçtürk and J.H. Ridd , J. Chem. Soc. Perkin Trans. II, 965 (1982).
0. H.B. Sun, R. Hua and Y. Yin, J. Org. Chem., 70, 9071 (2005).
1. A.R. Pourali and F. Fatemi, Chin. Chem. Lett., 21, 1283 (2010).
2. N. Nowrouzi and M. Zareh Jonaghani, Tetrahedron Lett., 52, 5081
(2011).
ACKNOWLEDGEMENTS
This work is Financially Supported by the Natural
Science Foundation of China (21161014), National key basic
Research Development Program (973 Program) project of
China (2012CBA01204), the Foundation of TrainingAcademic
and Technical Leaders for Main Majors of Jiangxi
2
2
3. X.M. Ma, B.D. Li, M. Lu and C.X. Lv, Chin. Chem. Lett., 23, 73 (2012).
4. M. De Lucia, L. Panzella, O. Crescenzi, A. Napolitano, V. Barone and
M. d'Ischia, Bioorg. Med. Chem. Lett., 16, 2238 (2006).
25. C. Fimognari and P. Hrelia, Mutat. Res. Rev. Mutat., 635, 90 (2007).
26. A. Lapczynski, L. Jones, D. McGinty, S. Bhatia, C. Letizia and A. Api,
(
2007DD00800).
Food Chem. Toxicol., 45, S428 (2007).
7. L. Peri, D. Pietraforte, G. Scorza, A. Napolitano, V. Fogliano and M.
2
REFERENCES
Minetti, Free Radic. Biol. Med., 39, 668 (2005).
28. M. d'Ischia, L. Panzella, P. Manini and A. Napolitano, Curr. Med. Chem.,
13, 3133 (2006).
1
2
3
.
.
.
A. Cornelis and P. Laszlo, Synthesis, 909 (1985).
J.L. Grenier, J.P. Cotelle, P. Catteau, Synth. Commun., 29, 1201(1999).
J.M. Mellor, S. Mittoo, R. Parkes and R.W. Millar, Tetrahedron, 56,
29. J.L. Williams, P. Ji, N. Ouyang, L. Kopelovich and B. Rigas, Exp. Cell Res.,
317, 1359 (2011).
8
019 (2000).
N. Haghnazari, C. Karami, K. Ghodrati and F. Maleki, Int. Nano Lett.,
, 30 (2011).
4
5
.
.
30. Y. Zhang,Y. Huang, X. Deng,Y. Xu, Z. Gao and H. Li, Eur. J. Pharmacol.,
680, 95 (2012).
1
J.M. Riego, Z. Sedin, J. Zaldívar, N.C. Marziano and C. Tortato, Tetra-
hedron Lett., 37, 513 (1996).
31. Y.Z. Liu, X. Li, L. Zhang andY.X. Li, Appl. Chem. Ind., 38, 1571 (2009).
32. Y.Z. Liu, L. Zhang, X. Li and Y.X. Li, Acta Phys. Chim. Sin., 25, 2118
(2009).
6
7
.
.
F. Chávez, S. Suárez and M.A. Díaz, Synth. Commun., 24, 2325 (1994).
N. Iranpoor, H. Firouzabadi, N. Nowrouzi and D. Firouzabadi, Tetra-
hedron Lett., 47, 6879 (2006).
33. Y.Z. Liu, Y.X. Li, X. Li and L. Zhang, Appl. Chem., 27, 432 (2010).
34. Y.Z. Liu, Y.X. Li, L. Zhang and X. Li, Acta Cryst., E65, o1716 (2009).
35. J.F. Queiroz, J.W.M. Carneiro,A.A. Sabino, R. Sparrapan, M.N. Eberlin
and P.M. Esteves, J. Org. Chem., 71, 6192 (2006).
36. G. Elias, B.J. Mincher, S.P. Mezyk, J. Muller and L.R. Martin, Radiat.
Phys. Chem., 80, 554 (2011).
8
9
1
1
1
.
.
A. Bose, W.P. Sanjoto, S. Villarreal, H. Aguilar and B.K. Banik, Tetra-
hedron Lett., 48, 3945 (2007).
P.-C. Wang, M. Lu, J. Zhu,Y.-M. Song and X.- Xiong, Catal. Commun.,
1
4, 42 (2011).
0. P.J. Campos, B. García and M.A. Rodríguez, Tetrahedron Lett., 41,
79 (2000).
1. H. Firouzabadi, N. Iranpoor and M. Zolfigol, Synth. Commun., 27,
301 (1997).
37. S. Ito, Y. Ishikawa, S. Nishino, T. Kobayashi, S. Ohba and Y. Nishida,
Polyhedron, 17, 4379 (1998).
9
38. G.C. Zhen, S.Y. Xiao, X.J. Mu and Z.N. Xia, Guangzhou Chem., 31,
37 (2006).
3
2. H. Suzuki, S. Yonezawa, N. Nonoyama and T. Mori, J. Chem. Soc.,
Perkin Trans. I, 2385 (1996).