Synthesis of new macrocyclic complexes of transition metals: Structural characterization and biological activity

Article abstract of DOI:10.1134/S107036321707026X

Condensation reaction between benzildihydrazone and pyridine 2,3-dicarboxylic acid, pyridine 3,4-dicarboxylic acid or pyridine 2,4-dicarboxylic acid in methanol led to novel Schiff base macrocyclic ligands L₁, L₂, and L₃ respectively. Metal complexes of the type [MLCl2], [M = Co(II), Ni(II)], were synthesized by the reaction of a free macrocyclic ligand (L) with the corresponding metal salts in a 1 : 1 molar ratio. The complexes were characterized on the basis of analytical data, molar conductivity and magnetic susceptibility measurements, IR, ¹H, and ¹³C NMR, and electronic spectral data. Those demonstrated that all the complexes had octahedral arrangement around the metal ions. The ligand and its complexes were screened for their antibacterial, antifungal and DNA cleavage activities. The studies demonstrate that the complexes possessed antimicrobial and DNA cleavage activities.

Full text of DOI:10.1134/S107036321707026X

ISSN 1070-3632, Russian Journal of General Chemistry, 2017, Vol. 87, No. 7, pp. 1610–1617. © Pleiades Publishing, Ltd., 2017.
Synthesis of New Macrocyclic Complexes
of Transition Metals: Structural Characterization
and Biological Activity1
K. Soni*, R. V. Singh, and N. Fahmi**
Department of Chemistry, University of Rajasthan, Jaipur, 302004 India
e-mail: *sonikshipra1989@gmail.com; **nighat.fahmi@gmail.com
Received March 23, 2017
Abstract―Condensation reaction between benzildihydrazone and pyridine 2,3-dicarboxylic acid, pyridine 3,4-
dicarboxylic acid or pyridine 2,4-dicarboxylic acid in methanol led to novel Schiff base macrocyclic ligands
L1, L2, and L3 respectively. Metal complexes of the type [MLCl2], [M = Co(II), Ni(II)], were synthesized by the
reaction of a free macrocyclic ligand (L) with the corresponding metal salts in a 1 : 1 molar ratio. The
complexes were characterized on the basis of analytical data, molar conductivity and magnetic susceptibility
1
measurements, IR, H, and 13C NMR, and electronic spectral data. Those demonstrated that all the complexes
had octahedral arrangement around the metal ions. The ligand and its complexes were screened for their
antibacterial, antifungal and DNA cleavage activities. The studies demonstrate that the complexes possessed
antimicrobial and DNA cleavage activities.
Keywords: Ni(II) and Co(II), macrocyclic complexes, spectral analysis, antibacterial activity, antifungal
activity, DNA cleavage activity
DOI: 10.1134/S107036321707026X
INTRODUCTION
RESULTS AND DISCUSSION
Importance of macrocyclic complexes in biological
processes [1, 2], catalysis [3], radio therapeutic and
medical imaging [4] has been demonstrated. Macro-
cyclic ligands can be used in systematic alteration of
kinetic and thermodynamic factors that indicate the
patterns of transition metals reactivity [5–7].
A [2+2] condensation reaction between benzildi-
hydrazone and pyridine dicarboxylic acid in methanol
resulted in formation of novel Schiff base macrocyclic
ligands (L), that upon subsequent treatment with
appropriate metal salts in a 1 : 1 molar ratio in
methanol yielded macrocyclic complexes of the type,
[MLCl2] [M = Co(II), Ni(II)] (Scheme 1). The ligands
and their complexes were stable at room temperature
and soluble in dimethylformamide and dimethyl
sulfoxide. Formation of ligands and their complexes
was ascertained by elemental analyses (Table 1), FT-
IR (Table 2), and H and C NMR spectra (Table 3).
Overall geometry of the complexes was inferred from
the values of magnetic moments and electronic spectra
[17]. Low values of molar conductances of 10−3 molar
solutions of the complexes in dry DMF (12–
21 Ω−1 cm2 mol−1) indicated their non-electrolytic nature.
Aza-macrocyclic ligands were tested in recognition
of DNA, RNA and related biomolecules [8–10].
Macrocyclic Schiff base ligands are characterized by
their mixed hard-soft donor character and versatile
coordination behavior [11, 12], enantioselective catalytic
reactions [13] and various biological activities [14].
Polyamide macrocycles have been used in construction
of the corresponding polyazamacrocyclic complexes
[15, 16].
1
13
Herein, we report a new series of three novel Schiff
base macrocyclic ligands and their transition metal
complexes of the type, [MLCl2] (M = Co(II), Ni(II))
and their biological properties.
IR spectra. In the spectra of ligands the sharp band
in the region of 3230–3275 cm–1 was attributable to the
non-coordinated amide nitrogen [18] due to cycliza-
tion. Strong absorption bands (1580–1605 cm–1) in-
dicated condensation of the OH group of diacids and
the NH2 group of benzildihydrazone and formation of
1 The text was submitted by the authors in English.
1610

SYNTHESIS OF NEW MACROCYCLIC COMPLEXES OF TRANSITION METALS
1611
Scheme 1. Synthesis of macrocyclic complexes.
O
R
O
R
O
C
C
C
HN
NH
N
Cl
NH
N
Ph
Ph
N
Ph
Ph
.
Ph
Ph
methanol
Ph
Ph
MCl 6H O
+
2
2
M
Cl
R
1 : 1
reflux
9−10 h
N
N
NH
Metal salt
N
NH
HN
C
C
C
O
O
R
O
Macrocyclic complex
Macrocyclic ligand, L
(L3), M = Ni, Co.
(L1),
(L2),
R =
N
N
N
macrocyclic Schiff bases. The low value of ν(C=N)
stretching vibrations at 1580–1605 cm–1 indicated a
drift of the lone pair of azomethine nitrogen towards
the metal atom [19]. Accordingly, coordination took
place via nitrogen of the C=N groups. Four recorded
amide bands were similar to those reported for other
macrocyclic complexes [20]. The bands of the C=O
group (1690–1708 cm–1) indicated that oxygen of the
carbonyl group was not coordinated to the metal atom.
The band in the region of 425-472 cm–1 could be
assigned to ν(M–N) and indicated that the complexa-
tion took place via the nitrogen atom [21].
NMR spectra. Absence of characteristic peaks of
1
protons of the amino group in H NMR spectra
confirmed the process of cyclization [22] (Table 3).
Electronic spectra. Geometry of metal ions in the
complexes was determined from the position and
Table 1. Analytical data and physical properties for the ligands and their complexes
Found, %
Calculated, %
MW
mp,
°C
Molar
conductivity
Compounds
L1
L2
L3
Color
C
H
N
M
–
C
H
N
M
–
found calculated
147 Yellow 71.70 4.78 18.95
145 Yellow 71.70 4.80 18.94
142 Yellow 71.70 4.80 18.94
71.79 4.82 18.96
71.79 4.82 18.96
71.79 4.82 18.96
738.70
738.72
738.75
739.75
–
–
–
–
–
–
738.72 738.75
–
[Ni(L1)Cl2]
212 Light
green
58.0 3.46 16.10 6.72 58.09 3.48 16.13 6.76 867.12 868.35
20.0
[Ni(L2)Cl2]
[Ni(L3)Cl2]
[Co(L1)Cl2]
[Co(L2)Cl2]
[Co(L3)Cl2]
213 Light
green
58.05 3.45 16.10 6.72 58.09 3.48 16.13 6.76 867.96
58.05 3.44 16.10 6.72 58.09 3.48 16.13 6.76 867.95
868.35
868.35
17.0
21.2
20.1
18.0
19.0
215 Light
green
220 Light
yellow
57.95 3.43 16.05 6.73 58.08 3.48 16.13 6.78 867.11 868.59
1
225 Light
yellow
57.02 3.45 16.05 6.73 58.08 3.48 16.13 6.78 867.11
868.59
222 Light
yellow
58.01 3.40 16.09 6.74 58.08 3.48 16.13 6.78 867.12
868.59
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1612
SONI et al.
Table 2. IR spectra bands (cm–1) of the ligands and their corresponding complexes
Compound
L1
L2
ν(N–H)
ν(amide)
1230
ν(M–N)
ν(C=N)
3230
3248
3230
3242
3240
3245
3245
3275
3255
1670
1685
1695
1700
1715
1710
1700
1695
1695
1530
1520
1525
1550
1545
1550
1560
1555
1552
640
638
642
670
655
665
645
635
640
–
1622
1621
1622
1605
1602
1585
1590
1592
1580
1230
1230
1240
1242
1250
1235
1240
1243
–
L3
–
[Ni(L1)Cl2]
[Ni(L2)Cl2
[Ni(L3)Cl2
[Co(L1)Cl2
[Co(L2)Cl2
[Co(L3)Cl2
435
435
435
470
471
472
Table 3. 1H and 13C NMR spectral data for the ligands
NMR spectra, δ, ppm
1H
13C
Ligand
–NH, s
Ar-H, m
phenyl-C
pyridine-C
C=N
CONH
L1
L2
L3
8.74–8.99 7.2312–7.9373 125.54, 126.08, 126.52, 127.50,127.70, 147.17,147.25, 166.50,
191.51,
195.21
128.92, 129.00, 129.15, 129.62,
129.67,130.80,139.42, 141.24
147.82, 149.76 167.67
8.74–8.99 7.3097–7.9258 125.50, 126.52, 127.51, 128.36, 128.83, 147.15, 147.45, 166.45,
129.25, 129.57,131.35 136.49, 137.77, 147.98, 151.48, 167.89
191.55,
195.2
139.42, 141.33
152.40
8.74–8.99 7.2312–7.9373 125.51, 126.26, 127.67, 128.29, 128.90, 147.65, 148.53, 166.48,
129.10, 129.36, 129.69, 131.88,139.40, 148.69, 150.76, 167.77
191.45,
195.23
139.59, 141.34
152.60
number of the d–d transition peaks in the electron
absorption spectra (Table 4). The spectra of Co(II) and
Ni(II) complexes were recorded at room temperature.
The accumulated data were in good agreement with the
literature data on the high spin six-coordinated
octahedral complexes, according to which the high
spin octahedral Co(II) complex is characterized by
complexes was less than the unit due to the metal
bonding to the ligand having a partially covalent
character. Electronic spectra of Ni(II) complex [NiLCl2],
exhibited three bands in the regions 9925–9980, 15095–
15480, and 24814–25740cm–1 assigned to the 3A2g(F) →
3T2g(F) (ν1), 3A2g(F) → 3T1g(F) (ν2), and 3A2g(F) → 3T1g(P)
(ν3) transitions respectively in an octahedral environ-
ment. The value of Racah parameter B’(756.33) was
less than the free ion value (1040) indicating a
considerable covalent character of the metal-ligand
bond. The ν2/ν1 ratio (1.51–1.55) confirmed octahedral
coordination of Ni(II) ion. The ligand field parameters
(Δq, B, β, and β%) demonstrated that contribution of
the covalent bond in the metal-ligand bonding was
significant [23].
4
three electron transitions: T1g(F)→ 4T2g(P) (ν1),
4T1g(F)→ 4A2g(F) (ν2), and 4T1g(F)→ 4T1g(F) (ν3). Spec-
tra of the Co(II) complexes contained three absorption
bands in the regions 9110–9130, 18400–18455, 21700–
22850 cm–1 of high spin octahedral complexes, transi-
tion energy ratio of the second to the first was 2.0–2.1.
The ligand field parameters (Δq, B, β, and β%) were
calculated for the Co(II) complexes. The Racah param-
eter (B) was found to be 846–917 cm–1 (< 971 cm–1),
which indicated that the ligand and the metal orbits
overlapped. The nephelauxetic ratio (β) for the cobalt
Mass spectrum. The mass spectrum of [NiL2Cl2]
complex was studied as the representative case. Its
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SYNTHESIS OF NEW MACROCYCLIC COMPLEXES OF TRANSITION METALS
1613
Ligand
Ligand
Fig. 1. Fungicidal screening data for the ligands and their
Ni(II) and Co(II) [Inhibition after 96 h (%) (concentration
in ppm)]: (1) Aspergillus flavus 50 ppm, (2) Aspergillus
flavus 100 ppm, (3) Aspergillus flavus 200 ppm,
(4) Fusarium semitectum 50 ppm, (5) Fusarium semitectum
100 ppm, (6) Fusarium semitectum 200 ppm,
Fig. 2. Antibacterial screening data of the ligands and their
Ni(II), Co(II) complexes [diameter of inhibition zone (mm)
(concentration in ppm), after 24 h]: (1) Escherichia coli,
(+) 500, (2) Escherichia coli, (+) 1000, (3) Staphylococcus
aureus, (–) 500, (4) Staphylococcus aureus, (–) 1000.
molecular ion peak was observed at m/z 867.04 being
in good agreement with its molecular weight and the
monomeric nature of the complex.
groups. Delocalization of π-electrons over the entire
chelate ring enhances lipophilicity of the complexes.
Due to increased lipophilicity, the complexes can
easily penetrate into a lipid membrane and block the
metal binding sites of enzymes of microorganisms.
Such complexes also disturb cellular respiration, thus
blocking proteins synthesis, making further growth of
an organism impossible. In general, metal complexes
are more active than the ligands as they may serve as
principal cytotoxic species.
Biological screening. Antimicrobial assay. The
ligands and their complexes were evaluated for their
antimicrobial activity against two bacteria (Staphylo-
coccus aureus and Escherichia coli) and two fungi
(Fusarium semitectum and Aspergillus flavus) (Figs. 1
and 2). The results were compared with those of the
standard drug streptomycin for bacteria and
itraconozole for fungi. All the ligands and their
respective complexes were determined to be sensitive
against all fungal and bacterial strains tested. There
was recorded a considerable increase in toxicity of the
complexes as compared to the free ligands. Evidently,
the concentration plaid a vital role in enhancing the
degree of inhibition. The enhanced activity of the
synthesized complexes, as compared to the activity of
the ligands, could be explained in terms of the
Overtone’s concept and Tweedy’s chelation theory
[24, 25]. According to the Overtone’s concept, a lipid
membrane surrounding the cell facilitates the passage
of substances that dissolve in lipids making lipo-
solubility to be an important factor of antimicrobial
activity. Upon chelation, polarity of the metal ion was
reduced to a larger extent owing to overlapping of the
ligand orbitals and partial sharing of the positive
charge of the metal ion with the charge of the donor
DNA cleavage activity. Agarose gel electrophoresis
was used to study DNA cleavage activity of the
synthesized ligands and their Ni(II) and Co(II)
complexes of the type [NiLCl2] and [CoLCl2] (where
L = L1, L2 and L3) against Escherichia coli (ATCC
25922) [26, 27]. Under experimental conditions, the
ligands and their metal complexes demonstrated DNA
cleavage activity. Untreated DNA was not cleaved
(Fig. 3, band 1). The ligands (Fig. 3, bands 3–5) and
Ni(II) and Co(II) complexes (Fig. 3, bands 6–11)
generated different bands as compared with control E.
coli DNA (Fig. 3, band 2) due to the conversion of
supercoiled DNA into open circular forms by cleavage
of the plasmid DNA at a concentration of 5 μg/mL.
Ligands exhibited partial cleavage of DNA. Ni(II) and
Co(II) complexes demonstrated higher DNA cleavage
activity than the ligands. Difference in DNA cleavage
efficiency could be due to different binding affinities
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 87 No. 7 2017

1614
SONI et al.
Fig. 3. DNA cleavage gel diagram of synthesized compounds: (1) standard molecular weight marker; (2) control DNA of E. Coli;
(3–5) E. Coli DNA treated with the ligands L1, L2 and L3 respectively; (6–11)1 E. Coli DNA treated with (Ni L1Cl2), (Ni L2Cl2), (Ni
L3Cl2), (Co L1Cl2), (CoL2Cl2), (CoL3Cl2) complexes, respectively.
of the ligands and their respective metal complexes to
DNA.
in methanol (25 cm3) a methanolic solution (25 cm3) of
pyridine 2,3-dicarboxylic acid, pyridine 3,4-di-
carboxylic acid or pyridine 2,4-dicarboxylic
acid (0.334 g) was slowly added upon constant
stirring. Refluxing of the mixture lasted for 6–7 h. The
volatiles were evaporated leaving a light yellow solid
product, which was filtered off, washed repeatedly
with methanol and dried in vacuum.
EXPERIMENTAL
The chemicals benzil (Merck), hydrazinehydrate
(Merck) and pyridine dicarboxylic acids (Fluka) were
used as received. Metal salts (Merck) were com-
mercially available pure samples. Benzildihydrazone
was prepared by the reaction of benzil and hydrazine
hydrate in methanol in a 1 : 2 molar ratio.
Synthesis of macrocyclic complexes. Solution of a
ligand and either CoCl2 or NiCl2 in a 1 : 1 ratio were
stirred upon heating for 9–10 h. The corresponding
solid product was filtered off, washed with cyclo-
hexane and recrystallized from methanol (Table 1).
Purity of the compounds was tested by TLC using
silica gel-G as a stationary phase.
Molecular weights were determined by the Rast
Camphor method [28]. The metals content was
determined gravimetrically. Nitrogen was determined
by the Kjeldahl’s method [29]. Carbon and hydrogen
analysis was performed on a CDRI, Lucknow. IR
spectra (KBr pellets) were recorded on a Nicolet
Magna FTIR-550 spectrophotometer. 1H and 13C NMR
spectra were measured on a JEOL GSX 400MHz FX-
1000 spectrometer in DMSO-d6 using TMS as an
internal standard. Mass spectra were measured at
USIC, University of Rajasthan, Jaipur. Electronic spectra
were recorded on a Shimadzu-1800 UV spectrophotometer.
Biological activity. Antibacterial studies. The
newly synthesized ligands (L1–L3) and the complexes
were screened for the antibacterial activity against two
bacteria including Staphylococcus aureus (ATCC
29213), Escherichia coli (ATCC 25922) in accordance
to Kirby–Bauer disc diffusion method using Müeller-
Hinton agar (B Lal, Laboratories, Rajasthan, India).
The Müeller–Hinton agar medium containing beef
infusion 300 g, casamino acid 17.5 g, starch 1.5 g, agar-
agar 17.0 g, and sterilized water 1000 cm3 was pipetted
Synthesis of macrocyclic ligands (L1, L2 and L3).
To a solution of benzildihydrazone (2 mmol, 0.446 g)
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SYNTHESIS OF NEW MACROCYCLIC COMPLEXES OF TRANSITION METALS
1615
into a petri dish and allowed to solidify. pH of the agar
was adjusted to be 7.2–7.4 at room temperature. The
compounds were dissolved in DMSO in 500 and
1000 ppm concentrations [30, 31]. Paper discs
(Whatman no. 1 filter paper, diameter 6 mm) were
soaked in the solutions of varied concentrations, dried
and placed on the medium previously seeded with
organisms in petri dishes at a suitable distance. The
petri dishes were stored in an incubator at 35°C for
24 h. Streptomycin was used as standard (+ve control).
DMSO was used as the negative control. Antibacterial
activity of standard antibiotic Streptomycin was
recorded using the same method.
DNA cleavage analysis. Preparation of culture
media. The primary culture of E. coli (ATCC25922)
was inoculated on nutrient broth (peptone 5 g, beef
extract 3 g, sodium chloride 5 g, and distilled water
1000 mL at pH 7.0), which was autoclaved at 121°C
under 15 psi pressure for 15 min. The seeded media
was incubated at 37°C for 24 h on a shaker (180 rpm).
The secondary culture was obtained by transferring
this primary culture to the fresh nutrient broth by
adding an equal amount (25 mL each) of primary
culture and fresh medium. After 48 h of incubation of
secondary culture, DNA was isolated and the bands
were visualized on an UV transilluminator.
Antifungal activity. Antifungal activity of the
ligands and synthesized complexes were tested in vitro
against two pathogenic fungi, Fusarium semitectum
(ATCC 200360) and Aspergillus flavus (ATCC 204304)
by the well diffusion method [32]. Each tested culture
was streaked on to a non-inhibitory agar medium to
obtain isolated colonies. After incubation at 35°C
overnight, 4 or 5 well-isolated colonies were selected
with an inoculum’s needle and transferred to a tube of
sterile saline or nonselective broth. Inoculum was
prepared using the yeasts from a 24 h culture on
sabouraud dextrose agar, which was prepared by
dissolving sabouraud dextrose (65 g in 1000 cm3 of
distilled water). Petri dishes (8 cm diameter)
containing 20 cm3 of sabouraud dextrose agar as a
solid media for preparing wells were used for analysis.
The compounds were introduced in the well (6 mm)
after diluting in a definite amount of DMSO for
reaching concentrations of 50, 100, and 200 ppm.
These petri dishes were wrapped in polythene bags
containing a few drops of alcohol and placed in an
incubator at 35°C for 24–48 h. The controls were also
run and three replicates were used in each case. After
incubation, the diameter of the zones of complete
inhibition (including the diameter of the well) was
measured and recorded in ppm. The linear growth of
the fungus was obtained by measuring the diameter of
the fungal colony after four days and the percentage
inhibition was calculated as:
Isolation of DNA. A 1000-μL fresh bacterial
culture was centrifuged for 10 min to obtain a pellet.
To this pellet, 250 μL of cell lysis buffer (100 mmol/L
Tris, pH 8.0, 50 mmol/L EDTA, 50 mmol/L lysozyme)
was added and further centrifuged to obtain the
supernatant at 10 000 rpm (g value 11 410) for 10 min
and incubated for 1 h at –20°C. To the supernatant
250 μL of saturated phenol, chloroform and isoamyl
alcohol were added in the ratio of 25 : 24 : 1,
respectively, and the whole mixture was again
centrifuged to collect the upper aqueous layer. To the
collected aqueous layer, a double amount of chilled
ethanol and 50 μL of sodium acetate were added and
upon centrifugation precipitated DNA was separated.
The pellet was dried and dissolved in TAE buffer
(100 mmol/L Tris pH 8.0 adjusted with glacial acetic
acid, 10 mmol/L EDTA) and refrigerated.
Treatment of DNA with the samples. The
compounds (5 μg/mL) were added separately to the
DNA sample and mixtures were kept in an incubator at
37°C for 2 h.
Agarose gel electrophoresis. The agarose gel elec-
trophoresis method was used for analysis of cleaved
products. One percent agarose gel was prepared by
mixing 0.5 g of agarose and 50 mL of TAE buffer
(4.84 g Tris base, pH 8.0, 0.5 mol/EDTA/1 L) by
boiling until agarose dissolved completely. The
agarose solution was poured into the gel tank and the
temperature fixed at ca 60°C. Thickness of the gel was
around 0.5 to 0.9 cm. The gel was left undisturbed and
allowed to solidify at room temperature. The combs
were gently lifted after pouring the TAE buffer at level
of 0.5 to 0.8 cm above the gel surface, ensuring that
wells remained intact. Loading of the 100-μL DNA
samples (mixed with bromophenol blue dye in 1 : 1
ratio) was done carefully into the wells along with the
C − T
C
Inhibition % =
× 100%.
Here C is a diameter of the fungus colony in the
control plate after 96 h and T is a diameter of the
fungal colony in the test plates after the same period.
The antifungal screening data of compounds were
compared with the standard (Itraconazole) (Figs. 1 and 2).
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SONI et al.
9. Koike, T., Watanabe, T., Aoki, S., Kimura, E., and
Shiro, M., J. Am. Chem. Soc., 1996, vol. 118, no. 50,
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control and a constant voltage of 50 V was maintained
for ca. 30 min. The gel was removed and stained with
10.0 μg/mL ethidium bromide for 10–15 min and the
bands were visualized under a UV transilluminator to
determine the extent of DNA cleavage. The results
were compared with the standard DNA marker.
10. Shionoya, M., Ikeda, T., Kimura, E., and Shiro, M., J. Am.
Chem. Soc., 1994, vol. 116, no. 9, p. 3848. doi 10.1021/
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CONCLUSIONS
New Ni(II) and Co(II) macrocyclic complexes of
three ligands have been synthesized. Analytical and
spectroscopic data indicated that the complexes
possessed an octahedral geometry and the ligands were
coordinated to the metal atoms in a tetradentate
manner. Screening of antimicrobial activity and DNA
cleavage activity revealed that the complexes were
more potent than the free ligands.
12. (a) Sengupta, P., Dinda, R., Ghosh, S., and Sheldrick, W.S.,
Polyhedron, 2003, vol. 22, no. 2, p. 477. (b) Fenton, R.R.,
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ACKNOWLEDGMENTS
14. Bajju, G.D., Sharma, P., Kapahi, A., Bhagat, M., Kun-
dan, S., and Gupta, D., J. Inorg. Chem., 2013, vol. 2013,
ID 982965. doi org/10.1155/2013/982965
Financial assistance from the University Grant
Commission (UGC), New Delhi is gratefully acknow-
ledged through grant number F-41-4/NET/RES/JRF/
1386/6190.
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