Synthesis, characterization, NLO study, and antimicrobial activities of metal complexes derived from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H- chromen-4-one and sulfanilamide

Article abstract of DOI:10.1080/00958972.2011.579116

A series of metal(II) complexes ML (where M = Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II), and VO(II)) have been prepared from 3-(3-(2- hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one and sulfanilamide. The structures of the complexes have been inves

Full text of DOI:10.1080/00958972.2011.579116

This article was downloaded by: [RMIT University]
On: 09 October 2013, At: 00:06
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered
office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Coordination Chemistry
Publication details, including instructions for authors and
subscription information:
http://www.tandfonline.com/loi/gcoo20
Synthesis, characterization, NLO
study, and antimicrobial activities of
metal complexes derived from 3-(3-(2-
hydroxyphenyl)-3-oxoprop-1-enyl)-4H-
chromen-4-one and sulfanilamide
S. Sumathi a , P. Tharmaraj a , C.D. Sheela b , R. Ebenezer a & P.
Saravana Bhava c
a Department of Chemistry , Thiagarajar College , Madurai – 625
009, India
b Department of Chemistry , The American College , Madurai – 625
002, India
c Department of Chemistry , Vellaichami Nadar College ,
Virudhunagar – 626 001, India
Published online: 10 May 2011.
To cite this article: S. Sumathi , P. Tharmaraj , C.D. Sheela , R. Ebenezer & P. Saravana Bhava
(2011) Synthesis, characterization, NLO study, and antimicrobial activities of metal complexes
derived from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one and sulfanilamide,
Journal of Coordination Chemistry, 64:10, 1673-1682, DOI: 10.1080/00958972.2011.579116
To link to this article: http://dx.doi.org/10.1080/00958972.2011.579116
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the
“Content”) contained in the publications on our platform. However, Taylor & Francis,
our agents, and our licensors make no representations or warranties whatsoever as to
the accuracy, completeness, or suitability for any purpose of the Content. Any opinions
and views expressed in this publication are the opinions and views of the authors,
and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content
should not be relied upon and should be independently verified with primary sources
of information. Taylor and Francis shall not be liable for any losses, actions, claims,
proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or
howsoever caused arising directly or indirectly in connection with, in relation to or arising
out of the use of the Content.

This article may be used for research, teaching, and private study purposes. Any
substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &
Conditions of access and use can be found at http://www.tandfonline.com/page/terms-
and-conditions

Journal of Coordination Chemistry
Vol. 64, No. 10, 20 May 2011, 1673–1682
Synthesis, characterization, NLO study, and
antimicrobial activities of metal complexes derived from
3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one
and sulfanilamide
S. SUMATHIy, P. THARMARAJ*y, C.D. SHEELAz, R. EBENEZERy
and P. SARAVANA BHAVAx
yDepartment of Chemistry, Thiagarajar College, Madurai – 625 009, India
zDepartment of Chemistry, The American College, Madurai – 625 002, India
xDepartment of Chemistry, Vellaichami Nadar College, Virudhunagar – 626 001, India
(Received 8 December 2010; in final form 18 March 2011)
A series of metal(II) complexes ML (where M ¼ Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II),
and VO(II)) have been prepared from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-
4-one and sulfanilamide. The structures of the complexes have been investigated by elemental
analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, NMR, mass, and ESR
spectral studies. Conductivity measurements reveal that the complexes are non-electrolytes,
except the oxovanadium complex. Spectral and other data show square pyramidal geometry
for oxovanadium and octahedral for the other complexes. The redox behaviors of the copper
and vanadyl complexes have been studied through cyclic voltammetry. Antimicrobial activities
of the compounds against several microorganisms indicate that some complexes have higher
activity than free ligand. The compounds may serve as photoactive materials as indicated from
their characteristic fluorescence properties. The second harmonic generation efficiency of the
ligand was found to be higher than that of urea and KDP.
Keywords: 3-(2-Hydroxyphenyl)-3-oxoprop-1-enyl-4H-chromen-4-one; Sulfanilamide; Metal
complexes; Schiff base; Fluorescence; SHG
1. Introduction
The pronounced biological activity of metal(II) complexes of Schiff bases derived from
sulfa drugs has led to considerable interest in their coordination chemistry [1–5].
Sulfanilamide is a potent antibiotic because these drugs undergo metabolic alterations
in tissues [6–10]. Their Schiff bases and complexes were investigated for physiologically
relevant carbonic anhydrase and superoxide dismutase activities [11, 12]. Similarly,
chromones are a widespread class of naturally occurring oxygen-containing heterocyclic
compounds. The pharmaceutical and chemical significance of these compounds offers
interesting possibilities in exploring more pharmacological activities [13–19].
Condensation products of sulfa drugs with carbonyl groups are biologically active
and also have good complexing ability. Many drugs possess modified pharmacological
*Corresponding author. Email: ptharma@rediffmail.com
Journal of Coordination Chemistry
ISSN 0095-8972 print/ISSN 1029-0389 online ß 2011 Taylor & Francis
DOI: 10.1080/00958972.2011.579116

1674
S. Sumathi et al.
and toxicological properties when administered in the form of metal complexes.
3-Formylchromone readily reacts with primary amines in alcoholic medium yielding an
enamine-adduct which reacts further to give the corresponding Schiff base [20]. The role
of 3-formylchromones as versatile synthons in heterocyclic chemistry as well as their
pharmaceutical importance is well-known. These compounds also have interesting
photochemical properties [20]. Nonlinear optical (NLO) materials play an increasingly
important role in a wide range of photonic applications [21, 22]. In general, chalcone
belongs to the class of conjugated charge transfer compounds that show NLO
properties [23]. Several metal complexes derived from chalcones of chromone
derivatives [24] are reported, but no work has been reported on the above-mentioned
Schiff bases. Interesting structural features, NLO properties, and biological activities
of such compounds were key factors to carry out this investigation. In this study,
we present the characterization, biological screening, NLO properties, and fluores-
cence of 3-(2-hydroxyphenyl)-3-oxoprop-1-enyl-4H-chromen-4-imine-(bis-sulfanila-
mide) (HPOCS) and its metal complexes.
2. Experimental
All chemicals and solvents were purchased from commercial sources. Phosphorous
oxychloride, DMF, o-hydroxyacetophenone, and sulfanilamide were Merck India
products and used as supplied. Solvents were doubly distilled and stored in molecular
˚
sieves (4A) before use. For voltammetric experiments, tetrabutylammonium perchlorate
(TBAP, Sigma) was used as supporting electrolyte. NMR measurement was made on
a BRUKER 300 MHz spectrometer (Madurai Kamaraj University, Madurai). UV-Vis
spectra were recorded on a THERMO SPECTRONIC 6 HEXIOS ꢀ; fluorescence
spectra were performed on an ELICO SL174 spectrofluorometer (Lady Doak College,
Madurai) using DMSO as solvent. EI mass was recorded by TEOL-GC MATE-2
(IIT, Madras, Chennai). IR spectra were obtained on a SHIMADZU FTIR 8400 S
(Standard Fire Work College, Sivakasi). ESR spectra of the copper(II) and
oxovanadium complexes were done at 300 and 77 K (IIT, Mumbai) using TCNE
(tetracyanoethylene) as the g-marker. Magnetic susceptibilities of the complexes were
measured on a Sherwood Magnetic susceptibility balance Mk1 (Thiagarajar College,
Madurai). Cyclic voltammetric studies in DMSO were carried out on a CH Instrument
for basic electrochemical system using a platinum disc working electrode, platinum wire
counter electrode, and Ag/AgCl reference electrode for the oxovanadium complex and
for copper(II) complex, platinum working electrode was replaced by glassy carbon
electrode. Molar conductances of the complexes were measured in DMSO at room
temperature using a Systronic Conductivity Bridge 304. All the complexes were
screened for biological activity using the well diffusion method. The second harmonic
generation (SHG) conversion efficiency of the ligand was determined by modified
version of the powder technique (IISc, Bangalore).
2.1. Synthesis of Schiff base (HPOCS)
A mixture of 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one (HPOC)
(2.9 g, 1 mmol) [25] and sulfanilamide (3.4 g, 2 mmol) in ethanol was stirred for 6 h at

Sulfanilamide metal complexes
1675
O
O
O
O
HO
Piperidine
Ethanol
+
H3C
CHO
O
O
OH
O
O
O
S
H2N
NH2
+
2
O
O
OH
Piperidine Ethanol
O
N
OH
N
O
O
S
S
O
O
H2N
NH2
Figure 1. Synthesis of the Schiff base (HPOCS).
room temperature in the presence of piperidine [26]. The solution was concentrated
through rotary evaporation and the resulting residue was refrigerated overnight.
Reddish yellow solid was collected and recrystallized from ethanol. Yield: 68%, m.p.:
98ꢀC [1H-NMR, 14.25 ꢁ (s, 1H, –OH), 5.86–8.42 ꢁ (m, aromatic proton), 7.691 and
8.229 ꢁ (d, 15.3 Hz, olefinic trans coupling signals), 12.09 ꢁ (s, 2H, –SO2NH2)]. The EI
mass of the ligand (HPOCS) gives a molecular ion peak m/z at 600 (Supplementary
material). Figure 1 shows the synthesis.
2.2. Synthesis of metal(II) complexes
A solution of metal(II) chloride in ethanol (1 mmol) was stirred with an ethanolic
solution of HPOCS (0.5 g, 1 mmol) on a magnetic stirrer. Upon concentration, the
solid complex precipitated, was filtered, washed thoroughly with ethanol, and dried

1676
S. Sumathi et al.
in vacuum. The oxovanadium complex was synthesized by stirring under reflux and the
precipitated complex was collected by filtration, washed with ethanol, and dried under
vacuum.
2.3. NLO properties of ligand
The SHG efficiencies of HPOC and HPOCS were determined by modified version
of the powder technique developed by Kurtz and Perry [27]. The compound was ground
into powder and packed between two transparent glass slides. A Nd:YAG laser beam
of wavelength 1064 nm radiated the sample cell. The transmitted fundamental wave was
absorbed by a copper sulfate solution, which removes the incident 1064 nm light
and Filter BG-38 removed any residual 1064 nm light. Interference filter bandwidth
is 4 nm for a central wavelength of 532 nm. The green light is finally detected by
the photomultiplier and displayed on the oscilloscope. The second harmonic signal
was detected by a photomultiplier tube and displayed on a storage oscilloscope. The
efficiency of the sample was compared with microcrystalline powder of KDP and urea.
The input energy used in this particular setup is 2.2 mJ pulseꢁ1
.
2.4. Biological activity
Antimicrobial activities of the compounds were tested in vitro by the well diffusion
method [28] against Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus
aureus using agar nutrient as the medium; antifungal activity against the fungus
Candida albicans cultured on potato dextrose agar as medium was also tested. Stock
solution (10ꢁ3 mol Lꢁ1) was prepared by dissolving the compounds in DMSO and the
solutions were serially diluted to find the zone of inhibition. A well was made on
the agar medium inoculated with microorganisms and filled with the test solution. The
plate was incubated for 24 h for bacteria and 72 h for fungi at 35ꢀC. During this period,
the test solution diffused, and the growth of the inoculated microorganisms was
affected. The inhibition zone at each concentration was noted.
3. Results and discussion
The analytical data and physical properties of HPOCS and metal complexes are
presented in table 1. The molar conductances of the complexes imply that the complexes
are non-electrolytes except oxovanadium, which is a 1 : 1 electrolyte. The analytical
data of the complexes are in good agreement with the general formula [MLX ꢂ 3H2O],
where M ¼ Cu(II), Ni(II), Co(II), Zn(II), Mn(II), Cd(II); X ¼ Clꢁ and for VO(II)
[ML ꢂ 2H2O]X where X ¼ SO24ꢁ. The magnetic moments show paramagnetic Cu(II),
Co(II), and Ni(II) and are in agreement with six-coordinate octahedral metal (figure 2)
and the VO(II) complex shows square-pyramidal geometry.
3.1. 1H-NMR spectra
In comparison with 1H-NMR spectrum of HPOCS, phenolic –OH at 14.25 ꢁ
disappeared in the spectrum of the Zn(II) complex, indicating deprotonation upon

Sulfanilamide metal complexes
1677
Table 1. Analytical, molar conductance, and magnetic susceptibility data of Schiff base (HPOCS) and
metal(II) complexes.
Calculated (found), %
Conductance
(S cm2 mꢁ1
ꢂeff
(BM)
Compound
m.p. (ꢀC)
M
–
C
H
N
S
)
Schiff base
98
110
130
149
120
128
150
125
60.0(59.5) 4.0(3.9) 9.3(9.0) 10.6(10.2)
–
–
[CuLCl2ꢂ2H2O]
[CoLCl2ꢂ2H2O]
[NiLCl2ꢂ2H2O]
[ZnLCl2ꢂ2H2O]
[MnLCl2ꢂ2H2O]
[CdLCl2ꢂ2H2O]
[VOLꢂ2H2O]SO4
8.1(7.8) 46.8(46.2) 3.6(4.5) 7.2(6.8)
7.7(7.0) 47.1(46.6) 3.7(3.3) 7.3(7.0)
7.6(7.8) 47.0(46.8) 3.7(3.4) 7.2(6.9)
8.5(8.0) 46.6(46.1) 3.6(3.5) 7.3(7.2)
8.1(7.7) 46.5(46.1) 3.7(3.0) 7.2(6.7)
7.5(7.0) 44.1(43.6) 3.4(3.1) 6.7(6.5)
8.3(7.9)
8.4(8.0)
8.4(8.2)
8.2(7.9)
8.3(7.8)
7.8(7.2)
13
10
18
11
19
20
63
1.92
4.73
3.23
–
5.89
–
6.3(6.0) 45.0(44.7) 3.6(3.1) 7.0(6.5) 12.0(11.7)
1.78
O
Cl
O
O
N
S
N
M
S
H N
2
OH
O
2
O
H O
2
OH
2
H N
2
O
M=Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II)
Figure 2. Proposed structure of the metal(II) complexes.
complex formation. Shifts of olefinic trans proton signal downfield (7.8 and 8.3 ꢁ)
compared to the free ligand suggest zinc coordinated through azomethine. The signal
at 3.49 ꢁ is assigned to coordinated water [29]. No appreciable change is observed in the
other signals of this complex.
3.2. Mass spectra
The mass spectra of HPOCS and Cu(II) and Co(II) complexes have been recorded
(Supplementary material). The molecular ion peak for HPOCS was observed at
600 m/z, whereas for Cu(II) and Co(II), the peaks appeared at 752 and 748 m/z,
respectively, corresponding to [ML(H2O)3Cl].
3.3. IR spectra
The ligand shows a strong band at 3382 cmꢁ1 (table 2) characteristic of hydroxyl which
shifted to 3371–3348 cmꢁ1 upon complexation, indicating coordination [30]. The band
at 1649 cmꢁ1 characteristic of the azomethine group shifted to 1643–1625 cmꢁ1
indicating that the azomethine nitrogen is coordinated [30]. Bands at 1323 and
,

1678
S. Sumathi et al.
Table 2. IR spectral data (in cmꢁ1) of HPOCS and metal(II) complexes.
Coordinated
water ꢃ(OH)
Compound
ꢃ(OH)
ꢃ(C ¼ N)
ꢃ(M–N)
Schiff base
–
3382
3346
3348
3348
3350
3371
3367
3346
1649
1641
1643
1641
1641
1624
1629
1639
–
[CuLCl2ꢂ2H2O]
[CoLCl2ꢂ2H2O]
[NiLCl2ꢂ2H2O]
[ZnLCl2ꢂ2H2O]
[MnLCl2ꢂ2H2O]
[CdLCl2ꢂ2H2O]
[VOLꢂ2H2O]SO4
3444
3464
3464
3458
3462
3462
3471
425
428
454
464
460
459
432
Table 3. Electronic spectral data of metal(II) complexes.
Compound
Frequency (cmꢁ1
)
Transition
Geometry
[CuLCl2 ꢂ 2H2O]
22271
17152
INCT
Distorted octahedral
Distorted octahedral
2
2Eg ! T2g
4
[CoLCl2 ꢂ 2H2O]
[NiLCl2 ꢂ 2H2O]
[VOL ꢂ 2H2O]SO4
9606
15847
23148
4T1g(F) ! T2g(F)
4T1g ! A2g
4
4T1g(F) ! T1g(P)
4
3
10869
13440
24038
3A2g ! T2g
Distorted octahedral
Square pyramidal
3A2g ! T1g(F)
3
3A2g ! T1g(P)
3
2
13386
12376
22988
2B2 ! E
2B2 ! B1
2
2B2 ! A1
2
1153 cmꢁ1 are attributed to ꢃas(SO2) and ꢃs(SO2), respectively. These remain almost
unchanged in the complexes, indicating no coordination [31]. The IR spectrum of
HPOCS exhibits bands at 3251 cmꢁ1 assignable to ꢃ(NH2). The appearance of this
mode at almost the same frequency in all the complexes suggests no coordination.
In all the metal complexes, there are new bands at 420–464 cmꢁ1 assigned to ꢃ(M–N)
[32]. In the vanadyl complex, a band at 974 cmꢁ1 is attributed to V ¼ O frequency [33].
The coordinated waters in the complexes are indicated by a broad band at
3460–3577 cmꢁ1 and the two weaker bands at 750–800 and 694–732 cmꢁ1 are due to
ꢃ(–OH) rocking and wagging, respectively [34, 35].
3.4. Electronic spectra
Electronic absorption spectral data of the ligand and complexes recorded in DMSO are
given in table 3. The copper(II) complex shows bands assigned as an intraligand charge
2
transfer band (INCT) at 22,271 cmꢁ1 and a d–d band at 17,152 cmꢁ1 (2Eg ! T2g
transition) [36]. This band strongly favors an octahedral geometry, supported by the
magnetic susceptibility value (1.92 BM) [37]. The nickel(II) complex exhibits three d–d
3
3
bands [38] at 10,869, 13,440, and 24,038 cmꢁ1 assigned to 3A2g ! T2g, 3A2g ! T1g(F),

Sulfanilamide metal complexes
1679
Table 4. The spin Hamiltonian parameters of copper and vanadyl complexes.
(10ꢁ4 cmꢁ1
)
(10ꢁ4 cmꢁ1
)
(cm)
Complex
Aiso
giso
g
k
g
?
A
A
ꢀ2
ꢅ2
g /A
k
k
?
k
[CuLCl2 ꢂ 2H2O]
[VOL ꢂ 2H2O]SO4
143
100
2.28
2.11
2.34
2.12
2.16
2.01
173.4
91.1
34.2
26.8
0.48
1.02
2.3
1.12
134
232
3
3
and A2g ! T1g(P), respectively. The magnetic moment of Ni(II) complex is 3.23 BM
[39], characteristic of octahedral geometry. The cobalt(II) complex has three absorp-
4
4
tions [40] at 9606, 15,847, and 23,148 cmꢁ1, which are assigned as T1g(F) ! T2g(F),
4
4
4
4T1g(F) ! A2g(F), and T1g(F) ! T1g(P) transitions, respectively. The band at
9606 cmꢁ1 confirms the octahedral geometry, which is also consistent with its magnetic
moment of 4.73 BM [41]. For the vanadyl(II) complex, three bands at 13,386, 12,376,
and 17,513 cmꢁ1 are assigned to 2B2 ! E, 2B2 ! B1, and 2B2 ! A1, respectively.
A square pyramidal geometry [3] is proposed for this system, because it shows a band
at 12,376 cmꢁ1 and its magnetic moment value is 1.78 BM [33]. Structurally related
work exists in the noninvolvement in coordination of hetero NH2 group para to
–SO2NH-group [42], but this study consists of complexes coordinated through hetero
NH2 group para to –SO2NH2.
2
2
2
3.5. Electrochemical behavior
Cyclic voltammograms of the copper(II) complex in DMSO recorded at room
temperature using TBAP as the supporting electrolyte from 0.8 to ꢁ0.5 V show that the
peak current varies with scan rate and the Epa–Epc values are greater than 200 mV,
indicating irreversible reduction processes [43]. The ratio of anodic to cathodic peak
currents corresponding to the chemical change occurs with the electron transfer as
Cu(II) ! Cu(III) ! Cu(II) ! Cu(I) at Epa ¼ 0.211 V, and Epc ¼ 0.554 V. The oxovana-
dium complex exhibited two reduction peaks [44] at 0.463 and 0.296 V and one
oxidation peak at 0.537 V. The redox process involves V(IV) ! V(III) ! V(II) ! V(IV).
3.6. EPR spectra
EPR spectra of copper and oxovanadium complexes are important in studying the
metal ion environment. The complexes are recorded in DMSO at 300 and 77 K and
the spin Hamiltonian parameters of the complexes are listed in table 4. The observed
spectral parameters show g 4 g characteristic of an axially elongated octahedral
k
?
geometry [45]. The giso value is 2.28 indicating covalent character of the metal ligand
bond, supported from the fact that the unpaired electrons lies predominantly in the
dx2ꢁy2 orbital, as was evident from the value of the exchange interaction term G,
estimated from the expression G ¼ (g ꢁ 2.0023)/(g ꢁ 2.0023). The observed value
k
?
of G for copper complex (2.14) suggests that an exchange coupling is present and
misalignment is appreciable. The ꢀ2 value (0.48) indicates appreciable in-plane
covalency in the metal ligand bonding. The calculated value (g /A ) 134.9 cm for the
k
k
complex indicates a slightly distorted structure. The poor in-plane ꢄ bonding is reflected

1680
S. Sumathi et al.
Table 5. Fluorescence parameters of HPOCS and
its metal(II) complexes in DMSO.
Compound
Emission maximum (nm)
Schiff base
455, 520, 893
457
457, 523
460, 529
457, 523
511
[CuLCl2 ꢂ 2H2O]
[CoLCl2 ꢂ 2H2O]
[NiLCl2 ꢂ 2H2O]
[ZnLCl2 ꢂ 2H2O]
[MnLCl2 ꢂ 2H2O]
[CdLCl2 ꢂ 2H2O]
[VOL ꢂ 2H2O]SO4
525
456
in ꢅ2 values. The molecular orbital coefficients ꢀ2, ꢅ2 were calculated using the
following equations:
ꢀ2Cu ¼ A =p þ ð g ꢁ 2:0023Þ þ 3=7 ð g ꢁ 2:0023Þ þ 0:04,
jj
jj
?
ꢅ2Cu ¼ ð g ꢁ 2:0023ÞE=ðꢁ8ꢆꢀ2Þ:
The EPR spectrum of vanadyl complex shows a single vanadium is present. The g ,
jj
k
g , and A values suggest square pyramidal geometry. The molecular orbital
?
k
coefficients ꢀ2, ꢅ2 were also calculated [46]; the lower ꢀ2 compared to ꢅ2 indicates
that the in-plane ꢇ-bonding is more covalent than the in-plane ꢄ-bonding.
ꢀ2 ¼ ð2:0023 ꢁ g ÞE=8ꢆꢅ2,
jj
ꢅ2 ¼ 7=6ðꢁA =p þ A =p þ g ꢁ 5=14g ꢁ 9=14 gisoÞ:
jj
?
jj
?
3.7. Fluorescence
Spectral studies show that HPOCS and its complexes are fluorescent. HPOCS exhibits
a broad and strong emission band with maximum wavelengths 893, 520, and 455 nm
upon photo-excitation at 451 nm. Similarly, the above complexes were characterized
by emission bands at 457–529 nm. The emission band at 893 nm disappeared because
of the interaction of the ligand with metal ion (table 5). Significant differences in
the positions of emission maxima of Schiff base and its complexes establish the
complexation process [47].
3.8. NLO property
From the experimental data, HPOC and HPOCS show better second harmonic
efficiencies than urea and KDP, HPOC showing 1.6 and 6.9 times more activity than
urea and KDP, respectively, while HPOCS shows 1.1 and 4.6 times more activity than
urea and KDP, respectively.
3.9. Biological activity
The zone of inhibition values of the compounds against the bacteria and fungus
are summarized in table 6. Amikacin and ketoconazole were used as reference drugs

Sulfanilamide metal complexes
1681
Table 6. Antimicrobial activity of HPOCS and its metal complexes (zone of inhibition
in mma; concentration in 10ꢁ3 mol Lꢁ1).
Compound
P. aeruginosa
S. aureus
E. coli
C. albicans
Schiff base
7
9
8
8
7
12
15
12
18
16
8
R
8
12
9
16
7
16
15
10
12
15
16
20
16
17
16
13
R
12
12
R
18
9
R
[CuLCl2ꢂ2H2O]
[CoLCl2ꢂ2H2O]
[NiLCl2ꢂ2H2O]
[ZnLCl2ꢂ2H2O]
[MnLCl2ꢂ2H2O]
[CdLCl2ꢂ2H2O]
[VOLꢂ2H2O]SO4
Standard
18
R ¼ resistant.
aIts value observed is within the error limits of ꢃ1.
for antibacterial and antifungal activities, respectively. The observed values indicate
that most of the complexes possess higher activity than the free ligand. The antibacterial
activity of Cd(II) complex is more active than HPOCS and the standard drug amikacin
against E. coli. Similar studies [32, 42] reveal that Cu(II) and Ni(II) complexes show
relatively higher antimicrobial activities on bacteria and fungi. Such an increased
activity of the complexes can be explained on the basis of chelation theory [48] and
size of the metal ion. The mode of action of compounds may involve the formation
of a hydrogen bond with the active center of cell constituents resulting in interference
with normal cell process.
4. Conclusion
The Schiff base (HPOCS) complexes [ML] of Cu(II), Co(II), Ni(II), VO(II), Zn(II),
Mn(II), and Cd(II) derived from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-
chromen-4-one and sulfanilamide were synthesized and characterized by spectral and
analytical data. HPOC and HPOCS exhibit appreciable nonlinear properties in
comparison with KDP and urea, and can be utilized for further NLO investigations.
Most metal chelates show better antimicrobial activity than HPOCS, particularly
Cd(II) has higher activity than the standard one. Such increased activity of the metal
complex is of tremendous importance in the pharmaceutical field. Ligand and its metal
complexes are fluorescent.
Acknowledgments
The authors thank the Management of Thiagarajar College, Madurai, and one of the
authors (PT) thanks the Defence Research and Development Organization (DRDO),
New Delhi for financial support and SAIF, IIT, Bombay and SAIF, CDRI, Lucknow
for providing analytical techniques.

1682
S. Sumathi et al.
References
[1] R.C. Manurya, P. Patel, S. Rajput. Synth. React. Inorg. Met.-Org. Chem., 33, 801 (2003).
[2] R.C. Manurya, A. Pandey, D. Sutradhar. Indian J. Chem., 43A, 763 (2004).
[3] R.C. Manurya, S. Rajput. J. Mol. Struct., 24, 794 (2006).
[4] M.K. Gupta, H.L. Singh, S. Varshney, A.K. Varshney. Bioinorg. Chem. Appl., 1, 309 (2003).
[5] H.L. Singh, S. Varshney, A.K. Varshney. Appl. Organomet. Chem., 13, 637 (1999).
[6] S. Bellu, M. Rizzotto. Quim. Nova, 30, 1136 (2007).
[7] L.L. Brunton, J.S. Lazo, K.L. Parker. Goodman & Gilman’s The Pharmacological Basis of
Therapeutics, 11th Edn, McGraw-Hill, New York (2006).
[8] F. Martinez, C.M. Avila, A. Gomez. J. Braz. Chem. Soc., 14, 803 (2003).
[9] A. Cleasby, A. Wonacott, T. Skarzynski, R.E. Hubbard, G.J. Davies, A.E.I. Proudfoot, A.R. Bernard,
M.A. Payton, T.N.C. Wells. Nature Struct. Biol., 3, 470 (1996).
[10] A. Mastrolorenzo, C.T. Supuran. Met.-Based Drugs, 7, 49 (2000).
[11] J.R. Anacona, D. Lorono, M. Azocar, R. Atencio. J. Coord. Chem., 62, 951 (2009).
[12] L. Puccetti, G. Fasolin, D. Vullo, Z.H. Chohan, A. Schozzafava, C.T. Supyran. Bioorg. Med. Chem.
Lett., 15, 3096 (2005).
[13] T. Walenzyk, C. Carola, H. Buchholz, B. Konig. Tetrahedron, 61, 7366 (2005).
[14] O. Sherif, H. Abdel-Fattah, M. El-Ajily. J. Therm. Anal. Calorim., 74, 181 (2003).
[15] V. Arjunan, S. Subramanian, S. Mohan. Spectrochim. Acta, 60, 995 (2004).
[16] Y.S. Shim, K.C. Kim, K.A. Lee, S. Shrestha, K.H. Lee, C.K.J. Kim, H. Cho. Bioorg. Med. Chem. Lett.,
13, 1325 (2005).
[17] Y.A. Shim, K.C. Kim, D.Y. Chi, K.H. Lee, H. Cho. Bioorg. Med. Chem. Lett., 13, 2561 (2003).
[18] S. Shrestha, S.Y. Hwang, K.H. Lee, H. Cho. Bull. Kor. Chem. Soc., 26, 1138 (2005).
[19] K. Nakano, T. Nakayachi, S. Yasumoto, S.R.M.D. Morshed, K. Hashimoto, H. Kikuchi, H. Nishikawa,
K. Sugiyama, O. Amano, M. Kawase, H. Sakagami. Anticancer Res., 24, 711 (2004).
[20] A. Gaplovsky, J. Donovalova, M. Lacova, R. Mracnova, H.M. El-Shaaer. J. Photochem. Photobiol.
A – Chem., 136, 61 (2000).
[21] T. Verbiest, S. Houbrechts, M. Kauranen, K. Clays, A. Persoons. J. Mater. Chem., 7, 2175 (1997).
[22] L.R. Dalton, A.W. Harper, R. Ghosn, W.H. Steier, M. Ziari, H. Fetterman, Y. Shi, R.V. Mustacich,
A.K.Y. Jen, K.J. Shea. Chem. Mater., 7, 1060 (1995).
[23] H. Reyes, Ma. Concepcion Garcia, B.M. Flores, H. Lopez-Rebolledo, R. Santillan, N. Farfan. J. Mex.
Chem. Soc., 50, 106 (2006).
[24] N. Vaibhav, K. Rajendra, R. Balasaheb. J. Serb. Chem. Soc., 73, 1073 (2008).
[25] K.M. Hatzade, V.S. Taile, P.K. Gaidhane, V.D. Umare, A.G.M. Haldar, V.N. Ingle. Indian J. Chem.,
48B, 1548 (2009).
[26] P. Annaraj, M. Ponvel, P. Athappan. Transit. Met. Chem., 29, 722 (2004).
[27] S.K. Kurtz, T.T. Perry. J. Appl. Phys., 39, 3798 (1968).
[28] O.N. Irobi, M. Moo-Young, W.A. Anderson. Int. J. Pharm., 34, 87 (1996).
[29] A. Kulkarni, P.G. Avaji, G.B. Bagihalli, S.A. Patil, P.S. Badami. J. Coord. Chem., 62, 481 (2009).
[30] B.B. Subudhi, P.K. Panda, S. Sahoo. Iran. J. Pharm. Sci., 3, 245 (Autumn 2007).
[31] R.C. Maurya, A. Pandey, D. Suntradhar. Indian J. Chem., 43A, 763 (2004).
[32] R.M. Issa, S.A. Azim, A.M. Khedr, D.F. Draz. J. Coord. Chem., 62, 1859 (2009).
[33] C.D. Sheela, C. Anitha, P. Tharmaraj, D. Kodimuthri. J. Coord. Chem., 63, 884 (2010).
[34] G.B. Bagihalli, S.A. Patil, P.S. Badami. J. Iran. Chem. Soc., 6, 259 (2009).
[35] G. Singh, P.A. Singh, K. Singh, D.P. Singh, R.N. Handa, S.N. Dubey. Proc. Natl Acad. Sci. Ind.,
72A, 87 (2002).
[36] M.S.S. Babu, K.H. Reddy, P.G. Krishna. Polyhedron, 26, 572 (2007).
[37] F.A. Cotton, G. Wilkinson, C.A. Murillo, M. Bochmann. Advanced Inorganic Chemistry, 6th Edn,
Wiley, New York (1999).
[38] Y.S. Rao, B. Prathima, S.A. Reddy, K. Madhavic, A.V. Reddy. J. Chin. Chem. Soc., 57, 677 (2010).
[39] C.M. Sharaby. Spectrochim. Acta, 62, 326 (2005).
[40] M.M. Omar, G.G. Mohamed. Spectrochim. Acta, Part A, 61, 929 (2005).
[41] K.Y. El-Baradie. Monatsh. Chem., 136, 1139 (2005).
[42] M.S. Nair, S. Regupathy. J. Coord. Chem., 63, 361 (2010).
[43] R. Kannappan, R. Mahalakshmy, T.M. Rajendran, R. Venkatesan, P.S. Rao. Proc. Indian Acad.
(Chem. Sci.), 115, 1 (2003).
[44] A.B.P. Lever. Inorganic Electronic Spectroscopy, 2nd Edn, Elsevier, New York (1985).
[45] R.K. Ray, G.B. Kauffman. Inorg. Chim. Acta, 153, 207 (1990).
[46] S.S. Dodwad, R.S. Dhamnasakar, P.S. Prabhu. Polyhedron, 8, 1748 (1989).
[47] A. Majumder, M. Georgina, R.A. Mallick, N. Chattopadhyay, S. Mitra. Polyhedron, 25, 1753 (2006).
[48] N. Dharamaraj, P. Viswanathamurthi, K. Natarajan. Transit. Met. Chem., 26, 105 (2001).