Synthesis, characterization and antifungal activity of metal complexes of 2-(5-((2-chlorophenyl)diazenyl)-2-hydroxybenzylidene) hydrazinecarbothioamide

Article abstract of DOI:10.1080/10426507.2012.657310

New metal complexes of Co(II), Cu(II), Ni(II), Zn(II), Mn(II), Fe(III), Ru(III), UO₂(II), and VO(II) with the Schiff base, 2-(5-((2-chlorophenyl)diazenyl)-2-hydroxy- benzylidene) hydrazine-carbothioamide (H₂L) have been prepared and characterized by elemental and thermal analyses, FT-IR, UV-Vis, mass spectra, ¹H-NMR, and ESR as well as conductivity and magnetic moments measurements. The IR spectra showed that the ligand acts as neutral tridentate, neutral bidentate or monobasic tridentate ligand. The geometries of metal complexes were either octahedral or square pyramidal. The ESR spectra of the solid copper(II) complexes indicated an axial symmetry type of a d(x2-y2) ground state with considerably ionic or covalent environment. The effect of the presence of an azo group on the biological activity of the ligand was investigated. The ligand and its complexes are biologically inactive due to the presence of azo group. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the related elements to view the free supplemental file.

Full text of DOI:10.1080/10426507.2012.657310

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Synthesis, Characterization and
Antifungal Activity of Metal Complexes
of 2-(5-((2-Chlorophenyl)Diazenyl)-2-
Hydroxybenzylidene)
Hydrazinecarbothioamide
Abdou S. El-Tabl a , Mohamad M. E. Shakdofa b c , Ahmed M. A. El-
Seidy b d & Ahmed N. Al-Hakimi e
a Department of Chemistry, Faculty of Science , Menoufia
University , Shebin El-Kom , Egypt
b Inorganic Chemistry Department , National Research Center ,
Cairo , Egypt
c Department of Chemistry, Faculty of Science and Arts, Khulais ,
King Abdulaziz University , Saudi Arabia
d Chemistry Department, Faculty of Science , The Imam Muhammad
bin Saud Islamic University , Riyadh , Saudi Arabia
e Department of Chemistry, Faculty of Science , Ibb University , Ibb ,
Yemen
Accepted author version posted online: 23 Jan 2012.Published
online: 06 Aug 2012.
To cite this article: Abdou S. El-Tabl , Mohamad M. E. Shakdofa , Ahmed M. A. El-Seidy & Ahmed N.
Al-Hakimi (2012) Synthesis, Characterization and Antifungal Activity of Metal Complexes of 2-(5-((2-
Chlorophenyl)Diazenyl)-2-Hydroxybenzylidene) Hydrazinecarbothioamide, Phosphorus, Sulfur, and
Silicon and the Related Elements, 187:11, 1312-1323, DOI: 10.1080/10426507.2012.657310
To link to this article: http://dx.doi.org/10.1080/10426507.2012.657310
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Phosphorus, Sulfur, and Silicon, 187:1312–1323, 2012
Copyright ꢀC Menoufia University
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426507.2012.657310
SYNTHESIS, CHARACTERIZATION AND ANTIFUNGAL
ACTIVITY OF METAL COMPLEXES OF 2-(5-((2-
CHLOROPHENYL)DIAZENYL)-2-HYDROXYBENZYLIDENE)
HYDRAZINECARBOTHIOAMIDE
Abdou S. El-Tabl,1 Mohamad M. E. Shakdofa,2,3
Ahmed M. A. El-Seidy,2,4 and Ahmed N. Al-Hakimi5
1Department of Chemistry, Faculty of Science, Menoufia University,
Shebin El-Kom, Egypt
2Inorganic Chemistry Department, National Research Center, Cairo, Egypt
3Department of Chemistry, Faculty of Science and Arts, Khulais,
King Abdulaziz University, Saudi Arabia
4Chemistry Department, Faculty of Science, The Imam Muhammad bin Saud
Islamic University, Riyadh Saudi Arabia
5Department of Chemistry, Faculty of Science, Ibb University, Ibb, Yemen
GRAPHICAL ABSTRACT
Abstract New metal complexes of Co(II), Cu(II), Ni(II), Zn(II), Mn(II), Fe(III), Ru(III),
UO2(II), and VO(II) with the Schiff base, 2-(5-((2-chlorophenyl)diazenyl)-2-hydroxy-
benzylidene) hydrazine-carbothioamide (H2L) have been prepared and characterized by
elemental and thermal analyses, FT-IR, UV–Vis, mass spectra, 1H-NMR, and ESR as
well as conductivity and magnetic moments measurements. The IR spectra showed that
the ligand acts as neutral tridentate, neutral bidentate or monobasic tridentate ligand.
Address correspondence to Abdou S. El-Tabl, Department of Chemistry, Faculty of Science, Menoufia
University, Shebin El-Kom, Egypt. E-mail: asaeltabl@yahoo.com
1312

NEW METAL COMPLEXES WITH SCHIFF BASE
1313
The geometries of metal complexes were either octahedral or square pyramidal. The ESR
spectra of the solid copper(II) complexes indicated an axial symmetry type of a d(x2-y2) ground
state with considerably ionic or covalent environment. The effect of the presence of an azo
group on the biological activity of the ligand was investigated. The ligand and its complexes
are biologically inactive due to the presence of azo group.
Supplemental materials are available for this article. Go to the publisher’s online edition of
Phosphorus, Sulfur, and Silicon and the related elements to view the free supplemental file.
Keywords Thiosemicabazone; azo-dye; complexes; spectroscopic studies; Schiff base;
synthesis
INTRODUCTION
Many Schiff base transition metal complexes are reported to have anticancer and
antimicrobial activities.1–3 It was reported that some drugs have greater activity when ad-
ministered as metal complexes than that as free organic compounds.4 Hence, Schiff base
transition metal complexes may be an untapped reservoir for drugs.5,6 Recently, complexes
of transition and nontransition metals with Schiff base ligands are promising materials
for electronic applications due to their outstanding photo and electroluminescent (PL and
EL) properties, and the ease of synthesis that readily allows structural modification for
optimization of material properties.7–10 Zinc complexes of Schiff base became attractive
for their interesting fluorescent properties, in particular, the salicylideneamine–zinc(II)
complexes exhibit photo luminescence as well as electroluminescence.7,9 In view of the
above facts, this article aimed to the synthesis, identification and antimicrobial investigation
metal complexes of the Schiff base ligand, 2-(5-(2-chlorophenyl)diazenyl)-2-hydroxy ben-
zylidene)hydrazinecarbothioamide. The coordination behavior of this Schiff base toward
transition metals was investigated via the elemental and thermal analyses, IR, UV–Vis, mass
spectra, 1H-NMR and ESR as well as conductivity and magnetic moments measurements.
RESULTS AND DISCUSSION
The analytical (Table 1) and spectroscopic data (Tables 2 and 3) are compatible
with the formation of the ligand (Figure 1) and the suggested structures (Figure 2). The
complexes are colored, stable in air, and insoluble in H2O, ethanol, and nonpolar solvents
such as benzene. However, they are soluble in polar solvents such as DMF and DMSO. All
the complexes except complex (13) are nonelectrolytes.
Infrared Spectra (IR)
The mode of coordination of the ligand can be obtained by comparing the infrared
spectra of the complexes with that of the free ligand.11,12 Important spectral bands are
presented in Table 2. The infrared spectrum of the ligand (H2L) showed two medium bands
appeared at 3265 and 3158 cm−1 which may be assigned to the υ(NH2) and υ(NH) groups,
respectively.13 The very strong band at 1610 was assigned to the υ(C N) of the azomethine
group,14 while the bands at 3440 and 855 cm−1 was assigned to the hydroxyl12 and C S
groups, respectively.15
In all complexes the bands of the azomethine and thio-ketone were shifted to lower
wave number (9–15 cm−1 and 20–27 cm−1, respectively) with decreasing their inten-
sities which indicates their coordination to the central metal ion.11,16 In all complexes

1314

1315

1316

NEW METAL COMPLEXES WITH SCHIFF BASE
1317
except (4), (10), and (12), the band due to hydroxyl group were shifted to lower fre-
quency (13–36 cm−1) together with a lower intensity, which indicates the coordination
of the hydroxyl oxygen.12 In case of complex (4) this band disappeared indicating the
subsequent deprotonation of the phenolic proton prior to coordination,12 while in case
of complexes except (10) and (12) the hydroxyl signal almost found at its original place
with the same intensity which indicates that it is not involved in coordination. In all
complexes except (10) and (12) the band due to the phenolic ν(C O) were shifted to
higher wave number which further support its involvement in coordination.12 In all com-
plexes except (10) and (12) new bands appeared in the 505–545, 345–384, and 450–
467 cm−1 regions due to the υ(M–N), υ(M–S) and υ(M–O) vibrations, respectively.11,12,16,17
Complexes (10) and (12) showed new bands in the 510–540 and 340–380 cm−1 regions
due to the υ(M–N) and υ(M–S) vibrations, respectively.11, 12, 17 The chloro complexes
(3), (11), and (12) showed new band in the 298–400 cm−1 range due to the presence of
υ(M–Cl).17 The appearance of two characteristic bands in the ranges 1523–1550 cm−1 and
1310–1333 cm−1 in case of complexes (2) and (6)–(10) were attributed to υasym.(COO−)
and υsym.(COO−), respectively, indicating the participation of the carboxylate oxygen in the
complexes formation.16,17 The mode of coordination of carboxylate group has often been
deduced from the magnitude of the observed separation between the υasym.(COO−) and
υsym.(COO−). The separation value (ꢂ) between υasym(COO−) and υsym.(COO−) in this
complex was more than 200 cm−1 (202 cm−1) suggesting the coordination of carboxylate
group in a monodentate fashion.17,18 The vanadyl complex (13), showed signals at 1161,
1021, and 617 cm−1characteristic for the uncoordinated sulfate group which was further
confirmed from conductance value.17,19 The IR spectrum of the VO(II) complex display
a band at 980 cm−1 assigned to the stretching frequency of the υ(V O).20 In the case
of sulfate complex (5), new bands appeared at 1213, 1031, and 964 cm−1. These bands
indicate that sulfate ion is coordinated to the metal ion in a chelating unidentate fashion.21
Complex (4) showed two bands at 1479 and 1300 cm−1 indicating that the nitrate ion
is coordinated to the copper(II) ion as a monodentate ligand.22 The broad bands in the
3508–3480 cm−1 region are due to coordinated water or water of crystallization. The bands
for water of crystallization are different from those of coordinated water; the latter has
bands in the 970–930 cm−1 and 660–600 cm−1 regions. The presence of water molecules
within the coordination sphere in the hydrated complexes were supported by the presence
of bands at 3508–3480 cm−1, 1580–1595 cm−1, 920–940 cm−1, and 610–640 cm−1 due to
OH stretching, HOH deformation, H2O rocking, and H2O wagging, respectively.23,24
Molar Conductivity
The molar-conductance 1 × 10−3 M solution of the metal complexes in DMF at room
temperature are in the 9.6–20.2 ꢁ−1 cm2 mol−1 range, indicating their nonelectrolytic nature
of these complexes except complex (13). These confirmed that the anion is coordinated
to metal ion. The considerably high values of some complexes may be due to the partial
solvolysis by DMF.25
Electronic Spectra
The structure of the ligand reveals that the two lone pairs of electrons of azo group are
not the only interacting nonbonding electrons. Since Schiff base part of the ligand contains

1318
A. S. EL-TABL ET AL.
Figure 1 Preparation of 2-(5-((2-chlorophenyl)diazenyl)-2-hydroxybenzylidene) hydrazinecarbothioamide
(H2L).
nitrogen and sulphur atoms which also may be extra sources of lone pair of electrons.
Thus other n→π∗ transition is expected to take place from these nonbonding orbital
to different π∗ molecular orbital extending over such a large molecules. The electronic
spectral data of the ligand and its complexes in dimethylformamide (DMF) are given in
Table 3. The data reveal that the ligand comprises three sets of bands in the UV and visible
regions.26 The first set of the shortest wave length at 235 (ε = 0.1 × 10−4 mol−1cm2)
and 265 nm (ε = 2.9 × 10−4mol−1cm2) may be assigned to the π→π∗ transition in the
benzenoid moiety and intra ligand π→π∗ transition.27–29 The second set appears at 315,
and 335 may be assigned to n→π∗ of the azomethine and C = S groups.16,27 The third
set located at 400 nm which maybe corresponds to π→π∗ transition involving the π
electron of the azo group.26,29 The band located in the visible region at 500 nm can be
assigned to π→π∗ transition involving the whole electronic system of the compounds
with a considerable charge transfer character arising mainly from the phenolic moiety.26,29
Compared to the free ligand, the n-π∗ transitions of the complexes was shifted to some
extent, probably due to imino-nitrogen coordination to the metal ion. Copper(II) complexes
2
2
(2–5) showed bands in the range 615–680 nm assignable to B1g→ B2g transition. This
Figure 2 Suggested structural representations of metal complexes.

NEW METAL COMPLEXES WITH SCHIFF BASE
1319
suggests that these complexes have tetragonal distorted octahedral geometry30 (Figure 2).
These complexes exhibit magnetic moment due to its spin-only value in the 1.69–1.85 B.M.
The nickel complex (6) showed magnetic moment value of 3.31 B.M., which is in the normal
range observed for a high spin octahedral Ni(II) complex. Its electronic spectrum displays
3
3
a band at 680 nm which can be assigned to A2g(F)→ T1g(F) transition, consistent with
its octahedral stereochemistry31 (Figure 2). The cobalt(II) complex (7) showed to signals
4
4
4
4
at 590 and 645 assignable to A1g→ Eg and A1g→ B1g, respectively, with a magnetic
moment value of 4.96 B.M., in a high spin square pyramidal geometry32 (Figure 2). The
electronic absorption spectrum of manganese(II) complex (9) displays weak absorption
bands at 645 and 550 nm. These band may be assigned to 6A1g→ T1g (4G) and 6A1g→ Eg
(4G), transitions, respectively. These transitions are characteristic to manganese(II) ion
in octahedral geometry33 (Figure 2). This complex shows magnetic moment value equal
5.45 B.M., which are corresponding to five unpaired electrons and close to high spin
manganese(II) (d5). The high spin octahedral ferric complex (11) showed three bands at 540,
4
4
4
4
4
660, 870 assignable to 6A1g→ A1g(G), 6A1g → T2g(G), and 6A1g→ T1g(G), respectively,
with a magnetic moment value of 5.89 BM (Figure 2).34,35 The ground state of ruthenium(III)
in an octahedral environment is T2g, arising from the t5 configuration, and the first
2
2g
2
2
excited doublet levels in the order of increasing energy are A2g and T1g, arising from
the t42ge1g configuration. The ruthenium(III) complex (12) showed one band at 520 nm
2
2
34, 35
corresponding to the transition T2g→ T1g
(Figure 2). The electronic spectrum of
the vanadyl complex (13) has two bands in the visible region at 780 and 520 nm, which
2
3
2
2
are assigned to B2→ E and B2→ B1 transitions, respectively, as expected for a square
pyramidal geometry (Figure 2).25 This complex exhibits magnetic moment due to its spin-
only value of 1.73 B.M.
Electron Spin Resonance of Copper(II) Complexes
The X-band ESR spectra of the complexes provide further insight into the environ-
ment around the metal centers. The ESR spectra of the solid copper(II) complexes (2) and
(3) at room temperature show nonaxial type symmetry with three g-values gx = 2.241, gy
= 2.105, and gz = 2.059 and gx = 2.249, gy = 2.093 and gz = 2.044 for the two complexes
respectively (g2 - g3)/(g1- g2) < 1 ( = 0.344 and 0.314), indicating a d(x2 – y2) ground state
with covalent bond character.36–38 The ESR spectra of solid copper(II) complexes (4) and
(5) at room temperature are characteristic to d9 configuration and having an axial symmetry
type of a d(x2-y2)ground state which is the most common for copper(II) complexes.29,37,38
The g values are g|| = 2.48, 2.227; g = 2.074, 2.044 with giso = 2.21, 2.105, respec-
⊥
tively, suggest elongated tetragonal octahedral geometry.30,37,38 The trend of g-values show
g|| < g < ge(2.0023) confirmed the tetragonal distortion around the copper(II) ion cor-
⊥
responding to elongation the four fold symmetry axis z.37,39 In addition, exchange
coupling interactions between the copper(II) ion is explained by Hathaway expression
G = (g ((−2))/(g (−2). If the value of G < 4.0 a considerable exchange coupling is
↓
↓
present in the solid complex. If G < 4.0 the exchange interactions is negligible which is
typically as in the case of our complexes (4) and (5) (G = 6.49, 5.19) confirmed tetragonal
octahedral structures.39–41 Kivelson and Neiman showed that for ionic environment g|| is
≥ 2.3 but for covalent environment g|| < 2.3. The g||-values for complexes (4) and (5) are
2.48 and 2.227, respectively; consequentially the environment for 4 is considerably ionic
but for 5 it is covalent.40,41

1320
A. S. EL-TABL ET AL.
Table 4 The thermal analysis (TG) of some complexes
Temp.
range oC
Loss in weight
Found (calc.)
Composition of the
residue
No.
4
Assignment
130-180
275-335
350-650
115-175
245-360
370-630
195-225
255-345
360-580
195-230
250-300
330-680
120-155
320-380
400-490
7.33 (7.29)
Loss of two molecule of coordinated water
Loss of two nitrate ion (2HNO3)
Decomposition of the complex forming
Loss of one molecule of coordinated water
Loss of one sulphate ion (H2SO4)
Decomposition of the complex forming NiO
Loss of one molecule of coordinated water
Loss of Three chloride ions (3HCl)
Decomposition of the complex forming
Loss of two molecule of coordinated water
Loss of three chloride ion (3HCl)
Decomposition of the complex forming
Loss of one molecule of coordinated water
Loss of sulphate group
[HLCu(ONO2)]
[HLCu]
[CuO]
[H2LNi(OC(O)CH3)2]
[H2LNi]
NiO
[H2LFeCl3]
[H2LFe]
Fe2O3
[H2LRuCl3]
[H2LRu]
Ru2O3
12.68 (12.54)
66.98 (67.32)
3.51 (3.41)
22.27 (22.34)
62.48 (63.15)
3.53 (3.63)
22.38 (21.44)
58.14 (55.58)
3.18 (3.22)
18.055 (19.02)
58.97 (59.68)
3.60 (3.49)
6
11
12
13
[H2LV(O)].SO4
[H2LV(O)]
V2O3
18.16 (18.65)
65.97 (64.85)
Decomposition of the complex forming
Thermal Analysis of Some Complexes
The thermo-gravimetric analysis (TG) was measured in the temperature 20–800 ◦C
range and the results are shown in Table 4. The results show a good agreement in weight loss
between calculated and found formula. The results show that the complexes (4), (6), (11),
(12), and (13) generally decomposed in several steps. The first step is the elimination of
water of coordination, in the temperature 115–230 ◦C range. The second step is the loss of
anions in the 245–380 ◦C temperature range. The third step is the co◦mplete decomposition
of the complexes through degradation of the ligand in 350–680 C temperature range
leaving the metal oxide.
Antibacterial and Antifungal Screening
The microbial activities’ results of the ligand and its metal complexes showed
that all compounds are inactive toward gram-positive bacterium (Bacillus subtilis) and
gram-negative bacterium (Escherichia Coli), fungus (Aspergillusniger), and Yeast (Saccha-
romyces cerevisie). The most interesting point of biological measurement is that the ligand
and its complexes are biologically inactive while other types of thiosemicarbazide Schiff
base metal complexes such as benzyloxybenzaldehyde-4-phenyl-3-thiosemicarbazone42
derivatives, 2-3-dimethyl-1-phenyl-3-pyrazolin-5-thiosemicarbazone,43 2-acetylpyridine-
N(4)-cyclohexyl thiosemicarbazone,44 and thiosemicarbazones, semicarbazones, dithio-
carbazates, and hydrazide/hydrazones compounds45 are biologically active. So, we can say
that the biological activity of these compounds against both bacteria and fungi inhibited
due to the presence of azo group.
CONCLUSION
The synthesis of the new Schiff base H2L has been reported. Its metal complexes
with transition metals have been characterized and all the data collected are in agreement
with the proposed structures. The spectral data indicate that the ligand can behave as

NEW METAL COMPLEXES WITH SCHIFF BASE
1321
neutral bidentate, neutral tridentate, and monobasic tridentate, and coordinates through the
C N, C S, and C–S and/or deprotonated or protonated phenolic hydroxyl oxygen atom.
The study revealed octahedral geometry around Ni(II), Cu(II), Mn(II), Ru(III), and Fe(III)
complexes. However, square pyramidal geometry is suggested for cobalt(II) and vanadyl(II)
complexes. The biological results show that the ligand and its complexes are biologically
inactive against Gram positive bacterium (Bacillus subtilis), Gram negative bacterium
(Escherichia coli), Fungus (Aspergillus niger), and Yeast (Saccharomyces cerevisie). The
effect of substitution on the biological activity of the parent ligand may be positive or
negative. In this case, the effect was very negative and by comparing the previous results
of thiosemicabazonederivatives we can say that the azo group inhibits the activity of the
compound.
EXPERIMENTAL
Materials
All the reagents employed for the preparation of the ligand and its complexes were
of the best grade available and used without further purification.
Physical Measurements
The ligand and its metal complexes were analyzed for C, H, N, Cl, and S at the Mi-
croanalytical Laboratory, Cairo University, Egypt. 4-((4-chlorophenyl)diazenyl)-2-hydroxy
benzaldehyde was prepared by a published method.46 Standard analytical methods were
used to determine the metal ion content.47–50 IR spectra of the ligand and its metal com-
plexes was measured using KBr discs with a Jasco FT/IR 300E Fourier transform infrared
spectrophotometer covering the range 400–4000 cm−1 and in the 500–100 cm−1 region
using polyethylene-sandwiched Nujol mulls on a Perkin Elmer FT-IR 1650 spectropho-
tometer. Electronic spectra in the 200–900 nm regions were recorded on a Perkin–Elmer
550 spectrophotometer. The thermal analysis (TG) was carried out on a Shimadzu DT-
◦
◦
30 thermal analyzer from room temperature to◦800 C at a heating rate of 10 C/min.
Magnetic susceptibilities were measured at 25 C by the Gouy method using mercuric
tetrathiocyanatocobaltate(II) as the magnetic susceptibility standard. Diamagnetic correc-
tions were estimated from Pascal’s constant.51 The magnetic moments were calculated from
ꢀ
the equation: µeff. = 2.84 χMcorr.T . Molar conductances were measured on a Tacussel type
CD6NG conductivity bridge using 10−3M DMF solutions. 1H NMR spectrum was obtained
on Brucker Avance 400-DRX spectrometers. Chemical shifts (ppm) are reported relative
to TMS. ESR measurements of solid complexes at room temperature were made using a
Varian E-109 spectrophotometer, with DPPH as a standard material. TLC is used to confirm
the purity of the compounds.
Synthesis of Ligand
The ligand 2-(5-(2-chlorophenyl)diazenyl)-2-hydroxy benzylidene)hydrazinecarbo-
thioamide (H2L) was prepared by adding equimolar amounts of hydrazinecarbothioamide
(91 mg, 1.0 mmol) in ethanol (20 mL) to 4-((4-chlorophenyl)diazenyl)-2-hydroxy ben-
zaldehyde (261 mg, 1.0 mmol.) in ethanol 20 mL (Figure 1). The mixture was refluxed
while stirring for 4 h. The solid product was filtered off, washed with cold ethanol, followed

1322
A. S. EL-TABL ET AL.
by crystallization from ethanol and, finally, dried under vacuum over anhydrous CaCl2. 1H
NMR (300 MHz, DMSO): δ = 11.65 and 11.05 [s, OH and NH], 10.49 and 10.35 [s, NH2],
8.94 [s, 1H, HC = N], and δ = 6.50–8.67 [m, (8H) aromatic proton].
Synthesis of Metal Complexes
All metal complexes, except complex 13, were prepared by refluxing a hot
ethanol/water (7: 3) solution of the metal salts with a suitable amount of a hot ethanol
solution of the ligand using a 1:1 ligand:metal molar ratio. In the case of complex 13,
a water solution of VOSO4.H2O was used. The reaction mixtures were refluxed for 3h
accompanied by stirring. The products, which precipitated (except in complex 4), were
filtered off, washed with ethanol then by diethyl ether and dried in vacuum desiccators
over P4O10. For complex 4, no precipitation occured until 3 mL of diethyl amine was
added to the reaction mixture. The analytical data are given in Table 1.
In-vitro Antibacterial and Antifungal Activities
The antifungal and antibacterial activities of the newly synthesized Schiff base ligand,
its metal complexes, and metal salts were carried out in the Botany Department, Laboratory
of Microbiology, Faculty of Science, El-Menoufia University. They have been studied for
their antifungal and antibacterial activities by disc diffusion method.52,53
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