Science and Technology Indonesia e-ISSN:2580-4391 p-ISSN:2580-4405 Vol.
No.
October 2025 Research Paper Synthesis.
Characterization.
Anticancer, and Molecular Docking Investigations of Benzothiazole Metal Complexes Periyasamy Kavitha1 .
Nainamalai Vijayakumari1* 1 Government Arts College for Women.
Salem.
Tamil Nadu, 636008.
India *Corresponding author: vijayasiva1818@gmail.
Abstract The synthesized 2-aminobenzothiazoles based ligand reacted with various transition metal salts were smoothly converted to square planner complexes.
The synthesized transition metal complexes are analyzed by using various characterization techniques.
Anticancer activity of Schiff base ligand and synthesized metal complexes are examined against human prostate cancer cell line (DU.
MTT assay at different concentration .
, 2, 4, 8, 16, 32, 64, 128, 256, and 512 yuNg/mL).
The IC50 values of metal complexes and free ligand were 16.
21 (SBI C.
, 75.
98 (SBI N.
, 25.
53 (SBI C.
, 81.
71 (SBI Z.
, and 29.
ree ligan.
yuNg/mL respectively.
Among them SBI Co has more potent against human prostate cancer cell line (DU.
In contrast, the molecular docking study shows.
Cu (II) complex has significant inhibition against human 2W3L protein.
Keywords Schiff Base.
Metal Complexes.
Spectral Characterization.
Anticancer.
Molecular Docking Received: 4 March 2025.
Accepted: 6 July 2025 https://doi.
org/10.
26554/sti.
INTRODUCTION
Schiff base ligands have readily synthesized from primary amine reacted with carbonyl compounds as a result of azomethine nitrogen (Vigato and Tamburini, 2.
In particular, azomethine has donor atom of nitrogen and composed.
The nitrogen atom having donor atoms readily coordinated with the metal ions to formed dative bonds to produced coordination complexes (Supuran et al.
, 1.
Generally.
Schiff base ligands have exhibiting a remarkable pharmacological activities such as antiinflammatory (Iftikhar et al.
, 2.
antiviral (Alam et al.
, antimicrobial (Da Silva et al.
, 2.
, antituberculosis (Cordeiro and Kachroo, 2.
, antioxidant (Rana et al.
, 2.
and anticancer (Yin et al.
, 2.
Because of their intriguing physicochemical characteristics and wide variety of applications in various scientific fields, the majority of metal complexes with Schiff base ligands have recently become the focus of intensive research (Alminderej and Lotfi, 2021.
Alorini et al.
Lotfi, 2.
And also.
Schiff base ligands have also exhibited different coordination modes as a result which produced tri, tetra, penta, hexa, and heptadentate coordinated metal complexes (Alfonso-Herrera et al.
, 2022.
Alfonso-Herrera et al.
Liu and Hamon, 2019.
Raji and Bader, 2.
In this continuation, nitrogen, oxygen and sulphur containing heterocyclic compound has played a vital function in the medicinal chemistry (Zheng et al.
, 2.
Among them, nitrogen and sulphur containing heterocyclic compounds are extensively found in nature.
In addition, benzothiazoles based derivatives have been widely utilized pharmaceuticals industries as well as metallo-enzymes (Chen et al.
, 2012.
Venkatraman et al.
, 2010.
Yenilmez et al.
, 2.
Moreover, in the recent years thiazoles containing compounds are essential building block for synthesis of inorganic complexes (Abd-Elzaher et al.
, 2.
According to Turan-Zitouni et al.
, its bis-thiazole metal complexes shown significant activity against both the A549 and C6 cell lines, with IC50 values of 37.
3 A 6.
8 yuNg/mL and 11.
3 A 1.
yuNg/mL, respectively.
The bisN-phenyl-NAo-[.
hiophen-2-y.
carbamohydrazonothioato-nickel(II) and Cu(II) complex was exhibited excellent antiviral activity against HIV1 virus (Choudhary, 2.
Co2 .
Ni2 .
Cu2 , and Cd2 metal complexes was also shown excellent yu-amylase activity as well as moderate anti-oxidant activity (Singh and Bala, 2.
After subsequently, metal complexes based on hydrazone ligands (Co 2 .
Ni 2 .
Cu 2 , and Zn 2 ) have demonstrated antihypertensive properties.
of these, the copper complex and ligand demonstrated exceptional antihypertensive properties (Bakale et al.
, 2.
Then, benzothiazole Schiff bases based lanthanide .
complexes were shown good antibacterial activity against Staphylococcus aureus and Propionic bacteria acnes bacterial strains (Mishra et al.
, 2.
After that, benzothiazole based binary metal complexes have been established against Gram-positive Science and Technology Indonesia, 10 .
1120-1129 Kavitha et.
Figure 1.
The Synthetic Route for the Synthesis of SB1 and its Metal Complexes (Co (II).
Ni (II).
Cu (II) and Zn (II)) bacterial strain (Bacillus amyloliquefaciens & Staphylococcus aureu.
Gram-negative (Escherichia col.
and fungal strain (Macrophomina phaseolina & Sclerotium rolfsi.
respectively (Daravath et al.
The in-vitro results examined metal complexes were shown more significant activity than thiazole ligands, and modest activity when compared to standard drugs.
Additionally, metal complexes have good antioxidant and DNA cleavage ability against the pBR322.
Therefore, benzothiazole based metal complex has potent biological activities.
According to the literature investigation, we have described the preparation of SB-1 ligand by condensing of S1 with 2hydroxy-5-methylbenzaldehyde.
We have utilized benzothiazole Schiff base ligand for synthesis of various metal complexes including Co (II).
Ni (II).
Cu (II) and Zn (II).
The synthesized metal complexes were analyzed by using various spectroscopic The anticancer effectiveness of synthesized SB-1 and metal complexes were also studied.
EXPERIMENTAL SECTION
1 General Procedure for the Synthesis of (S.
2-Amino-6-nitrobenzothiazole .
g, 0.
025 mmo.
was dissolved in THF .
mL) with constant stirring at 0Ae5 C.
Subsequently, 8 mL of triethylamine .
076 mmo.
were added into the solution, followed by 2.
72 mL of acetyl chloride .
038 mmo.
, with 10 mL of THF added dropwise.
At room temperature, the resultant reaction mixture was stirred for six hours.
TLC
thyl acetate:hexane, 7:.
was used to monitor the reactionAos Ethyl acetate .
mL) and water .
mL) were used to extract the crude reaction mass.
Spectroscopic methods were used to analyse the obtained pure products.
2 General Procedure for the Synthesis of (S.
To a solution of S1 .
5 g, 0.
010 mmo.
in methanol .
, ammonium formate .
72 g, 0.
073 mmo.
and zinc dust .
63 g, 0.
073 mmo.
were added and the reaction mixture was A 2025 The Authors.
Figure 2.
FTIR Spectrum of .
SB1 .
Co .
Ni .
Cu .
Zn Complex stirred at 0-5 C for 45 minutes under room temperature.
Next, the reaction mass was filtered, resulting filtrate was evaporated under reduced pressure using rotary evaporator to furnished the pure product (S.
3 Procedure for the Synthesis of N-.
-(E)-[.
-Hydroxy-5Methylpheny.
Methyliden.
Amino-1,3-Benzothiazol-2y.
Acetamide Schiff Base (SB-.
A mixture of S2 .
5 g, 0.
007 mmo.
, 2-hydroxy-5-methylbenz aldehyde .
08 g, 0.
008 mmo.
, and a few drops of glacial acetic acid was dissolved in ethanol .
mL) (Abd-Elzaher et al.
, 2.
The reaction mixture was allowed to reflux for 8 The completion of the reaction was monitored by TLC.
Page 1121 of 1129 Science and Technology Indonesia, 10 .
1120-1129 Kavitha et.
Table 1.
FTIR Spectral Data of Ligand and Respective Transition Metal Complexes Ligand/Complex yuO
(OH)
yuO (ArAe CAeH) yuO
(C=O)
C17 H15 N3 O2 S
C34 H28 CoN6 O4 S2
C34 H28 NiN6 O4 S2
C34 H28 CuN6 O4 S2
C34 H28 ZnN6 O4 S2
(Amide NAeH) yuO
(C N)
yuO (C N yuO (CAeO) yuO (CAeS) yuO (MAe yuO (MAe Ae Ae Figure 3.
UV-Vis Spectrum of .
Co (II) .
Ni (II) .
Cu (II) .
Zn (II) Metal Complexes To generate the pure product (SB-.
, the corresponding solid powder was filtered, dried, and recrystallised from methanol.
4 Synthesis of Metal Complexes A mixture of N-.
-(E)-[.
-hydroxy-5-methylpheny.
methylide n.
amino-1,3-benzothiazol-2-y.
25 g, 0.
and Cu (NO.
2 A 6H2O .
118 g, 0.
0004 mmo.
was dissolved in methanol (Abd-Elzaher et al.
, 2.
The re- A 2025 The Authors.
action mixture was allowed to reflux for 4 h.
The obtained metal complex was filtered and rinsed with ethanol, dried under vacuum to remove excess solvent.
As per the following procedure, the individual metal complex was synthesized using Zn(NO.
6H2O.
CoCl2 A H2O and NiCl2.
6H2O metal salts.
Page 1122 of 1129 Kavitha et.
Science and Technology Indonesia, 10 .
1120-1129 38, 120.
77, 132.
86, 139.
59, 145.
62, 153.
05, 168.
LC-MS (ESI) m/z: 206.
27 (MAeH) .
N-.
-{(E)-[.
-hydroxy-5-methylpheny.
ami n.
-1,3-benzothiazol-2-y.
acetamide (SB-.
: 1.
92 g of SB-1, orange solid.
Yield 82%.
292Ae293 C.
FT-IR (KB.
yuOmax in cmOe1 : 3427 (N-H, amid.
, 3063 (C-H), 2956 (C-H, asymmetri.
, 2918 (C-H, symmetri.
, 1694 (C=O), 1612 (C=N), 1574 (N-H bendin.
, 1273 (C-N, amid.
, 708 (C-S).
Nuclear resonance of proton .
MHz.
DMSO-d6 ) yu ppm: 2.
, 3H), 2.
, 3H), 6.
, 1H), 7.
, 1H), 7.
, 1H), 50 .
, 1H), 7.
, 1H), 8.
, 1H), 8.
, 1H), 12.
, 1H), 12.
, 1H).
Nuclear resonance of carbon .
MHz.
DMSO-d6 ) yu ppm: 20.
38, 23.
18, 114.
64, 116.
85, 119.
75, 121.
44, 128.
11, 132.
61, 133.
03, 133.
33, 144.
01, 158.
46, 158.
74, 163.
00, 169.
LC-MS (ESI) m/z:
21 (M H) .
RESULTS AND DISCUSSION
Figure 4.
Proton Nuclear Magnetic Resonance of Schiff Base Ligand, 4 (B).
Carbon Nuclear Magnetic Resonance Spectrum of Schiff Base Ligand 5 Spectral Data of the Synthesized Compounds S1: Off-white solid.
Yield 65%.
284Ae285 C.
FT-IR
(KB.
yuOmax in cmOe1 : 3174 (N-H.
Stretchin.
, 3071 (C-H.
Stretchin.
, 2949 (C-H.
Stretc.
, 1701 (Carbonyl.
Stretchin.
, 1553, 1340 (Nitro group Stretchin.
, 883 (C-H, bendin.
, 748 (C-S Stretchin.
Nuclear resonance of proton .
MHz.
DMSO-d6 ) yu ppm: 2.
, 3H), 7.
, 1H), 8.
, 8.
, 1H), 12.
, 1H, amid.
Nuclear resonance of carbon .
MHz.
DMSO-d6 ) yu ppm: 22.
76, 118.
85, 120.
63, 132.
09, 142.
86, 153.
39, 163.
37, 170.
LC-MS
(ESI) m/z: 236.
21 (MAeH) Oe .
S2: Pale yellow solid.
Yield 72%.
251Ae252 C.
FT-IR
(KB.
yuOmax in cmOe1 : 3412, 3291 (N-H.
Stretching, amin.
, 3135 (C-H), 2917 (C-H), 1694 (Carbony.
, 1604 (C=N), 1553 (N-H, bendin.
, 1250 (C-N.
Stretchin.
, 845 (C-H, bendin.
Nuclear resonance of proton .
MHz.
DMSO-d6 ) yu ppm:
, 3H, methy.
, 5.
, 2H, amin.
, 6.
d, 1H), 6.
, 1H), 7.
, 1H), 11.
, 1H, amid.
Nuclear resonance of carbon .
MHz.
DMSO-d6 ) yu ppm: 22.
61, 104.
A 2025 The Authors.
The SB-1 was synthesized from the condensation of S1 and 2-hydroxy-5-methylbenzaldehyde, dissolved in ethanol with a few drops of glacial CH3COOH, followed by reflux conditions (Figure .
for an appropriate reaction time.
The corresponding ligand was directly reacted with metal salts such as Cu(NO.
6H2O.
Zn(NO.
6H2O.
CoCl2 A H2O, and NiCl2.
6H2O in a mixture of ethanol and methanol under reflux conditions.
The synthesized metal complexes were isolated by simple filtration.
These metal complexes are more soluble in polar aprotic solvents (DMSO) and exhibit higher melting points compared to SB-1.
The synthesized metal complexes were analyzed by spectroscopic techniques.
1 FTIR Spectral Analysis Table 1 showed the metal complexes .
Aos fourier transform infrared spectral data.
The synthesised SB1Aos FTIR spectrum revealed the azomethine (C N) group as a prominent, intense band at 1688 cm-1 .
The thiazole ringAos C N is represented by the peak that emerged at 1561 cm-1 .
The strong peaks that followed at 3249, 3182, 3049, and 1531 cm-1 are responses to the carbonyl moiety, aromatic C H, phenolic OH, and NH of acetamide, respectively.
Then, phenolic C O and C S C stretching vibration of thiazole ring was appeared at 1264 and 769 cm-1 .
Though, the azomethine (C N) moiety was appeared in the metal free ligand at 1695 cm-1 whereas metal complexes shifted at low intensity at 1681-1531 cm-1 , this is due to the azomethine coordinated to the metal ions as a result formation of transition metal complexes.
Additionally, the C N in the thiazole ring is exhibit a peak at 1584 cm-1 in the free ligand and metal complexes, which proved that C N moiety not involving the coordination of the metal ions.
Further.
SB1 and metal complexes were displayed a peak at 770-778 cm-1 , which indicates C S C stretching vibration of thiazole ring sulphur not involving the complexation.
In particular, the new bands displayed at 565-669 cm-1 and 469-476 cm-1 which is not found in the SB1, these bands corresponds to the Page 1123 of 1129 Kavitha et.
Science and Technology Indonesia, 10 .
1120-1129 Figure 5.
Mass Spectrum of Co Complex, (B).
Mass Spectrum of Ni, (C).
Mass Spectrum of Cu Metal Complex, (D).
Mass Spectrum of Zn Metal Complex M O and M N bonds in the metal complexes respectively (Figure .
2 UV-Vis Spectra Studies Every complexAos UV-Vis spectra were recorded at room temperature in DMSO.
The yuU-yuU* and n-yuU* charge transfer transitions for the azomethine and thiazole rings, respectively, are denoted by the bands at 280 and 342 nm in the free ligandAos UV-Vis The Co (II) complexAos UV-Vis spectra showed a band at 555 and 396 nm that was ascribed to the 2B1g - 2Eg Next, the Ni complex was shown a band at 562 and 388 nm corresponds to 1A1g - 1B1g transition.
Similarly, both Cu and Zn complexes were displayed broad band at 535-631 nm ascribed to the 2B1g - 2A1g and 2B1g - 2Eg transition (Figure .
Based on the previous literature report, the electronic spectral information was confirmed the complex formation (Vamsikrishna et al.
, 2.
A 2025 The Authors.
Every complexAos UV-Vis spectra were recorded at room temperature in DMSO.
The yuU-yuU* and n-yuU* charge transfer transitions for the azomethine and thiazole rings, respectively, are denoted by the bands at 280 and 342 nm in the free ligandAos UV-Vis spectrum.
The Co (II) complexAos UV-Vis spectra showed a band at 555 and 396 nm that was ascribed to the 2B1g - 2Eg transition.
3 1 H-NMR and 13 C-NMR Spectra Studies The 1 H-NMR spectrum of SB1 shows a singlet at yu 2.
22 ppm corresponding to the presence of CH3 group in the aromatic Next, the singlet was displayed at yu 2.
27 ppm corresponding to the methyl proton of the acetamide moiety.
The azomethine proton showed a singlet at yu 8.
95 ppm, and the aromatic ring displayed a singlet and doublets at yu 7.
43, 6.
86 ppm, respectively.
In the 13 C NMR spectrum, a peak at yu 169.
89 ppm corresponded to the presence of the carbonyl Page 1124 of 1129 Kavitha et.
Figure 6.
Interaction View 2W3L Protein with .
Schiff Base Ligand .
Co .
Ni .
Cu and Zn Complexes Science and Technology Indonesia, 10 .
1120-1129 the binding energy value of Co (II) is -326.
66 kcal/mol and it exhibited interaction with amino acid residue Asp99 .
72yI) with one conventional hydrogen bond interaction.
The binding energy value of Ni (II) complex is -333.
56 kcal/mol and exhibit three hydrogen bonding interaction with Glu94 .
12yI).
Arg98 .
34yI) and Tyr39 .
95yI).
Similarly, the binging energy of Cu (II) is -348.
85 kcal/mol and the amino acid residue Asn102 .
06yI) shown conventional hydrogen bonding interaction and also with pi-donor hydrogen bond interaction Arg105 .
61yI) whereas, the binding of Zn (II) complex is 52 kcal/mol, this value very less when compared to the Cu (II), while it shows two conventional hydrogen bonding interaction with Arg 26 .
18yI) and Arg 68 .
78yI).
The molecular docking study was strongly supported the biological performance of the complexes.
Figure 8.
DU145 Cell Viability After Sample Incubation (A) Figure 7.
DU145 Cell Viability Before Sample Incubation (A) SBI-Co, (B) SBI-Ni, (C) SBI-Cu, (D) SBI-Zn, (E) SBI And (F) Control group, and yu 163.
00 ppm was attributed to the azomethine Since the acetyl groupAos carbonyl carbon was present, the methyl proton showed a single peak at yu 20.
38 ppm and a singlet at yu 23.
18 ppm.
From yu 114 to 158 ppm, the remaining aromatic carbons were visible (Figures 4a & 4.
This extension of the ligandAos mass spectrum disclosed the molecular ion peak at m/z = 326.
Additionally, the complexesAo mass spectra showed that the Co.
Ni.
Cu, and Zn complexes had molecular ion peak values .
at 708, 707, 712, and 715, respectively (Figures 5aAe.
4 Molecular Docking Studies According to the molecular docking analysis, synthesized transition metal complexes of 6a, 6b, 6c and 6d were exhibited good to excellent binding energy with crystal structures of 2W3L human protein.
And also, the studies performed by using the Hex.
0 software and docking poses are depicted in Figure 6.
The binding energy value of Schiff base ligand is -263.
81 kcal/mol and it didnAot interact with the protein amino acid.
Next.
A 2025 The Authors.
SBI-Co, (B) SBI-Ni, (C) SBI-Cu, (D) SBI-Zn, (E) SBI And (F) Control 5 Anticancer Activity SBI-Co.
SBI-Ni.
SBI-Cu.
SBI-Zn, and SB1 were treated with DU145 to investigate the anticancer activity of the synthesized metal complexes, and the MTT assay was employed to determine the IC50 values (Table .
Particularly, before incubation of the metal complexes and free ligand on DU145 cell line, there was no change observed in the morphology of the cell line (Figure .
The cytotoxicity effect of all the prepared metal complexes and Schiff base ligand were studied using different concentrations from 1, 2, 4, 8, 16, 32, 64, 128, 256 and 512 yuNg/mL.
Significant anticancer activity was demonstrated by the synthesized metallic complexes and Schiff base ligand, even if the complexAos concentration was also raised from 1 to 512 yuNg/mL.
In addition, both the metal complexes and ligand shown 50% of cell death was observed form 16.
71 yuNg/mL (Figure .
Apparently.
SBI-Co.
SBI-Cu complexes and Schiff base ligand (SBI) have demonstrated the IC50 values such as 16.
21, 25.
53 and 29.
6 yuNg/mL respectively.
Meanwhile.
SBI Ni and SBI Zn complexes were shown IC50 98 and 81.
71 yuNg/mL.
The observed result clearly proved that, at low concentration of metal complexes like Co.
Page 1125 of 1129 Science and Technology Indonesia, 10 .
1120-1129 Kavitha et.
Table 2.
Preparation of Transition Metal Complexes of N-.
-{(E)-[.
-Hydroxy-5-Methylpheny.
Methyliden.
Amin.
-1,3- Benzothiazol-2-y.
Acetamide Ligand/Complex Molecular Formula Molecular Weight Time .
Colour Yield (%) C17H15N3O2S Orange solid C34H28CoN6O4S2 Brown solid C34H28NiN6O4S2 Dark brown solid C34H28CuN6O4S2 Maroon solid C34H28ZnN6O4S2 Dark grey solid Cu and SB1 were exhibited higher cytotoxic effect whereas.
Zn and Ni complex was shown less cytotoxic effect while increasing the concentration.
Furthermore, the microscopic analysis was examined morphological damage and significantly decreased cell density (Figure .
at the concentration of 512 yuNg/mL.
Among them.
SB1 Co complex was shown more potent towards DU145 cancer line when than the other metal complexes and ligand.
Therefore, the order of IC50 values are 16.
21 (SBI C.
, 25.
(SBI C.
, 29.
6 (SB.
, 75.
98 (SBI N.
(SBI Z.
yuNg/mL respectively.
Finally, the growth inhibition of cancerous cell was observed in Figure 9.
Finally, the order of potency of anticancer activity of IC50 trends are 16.
(SBI C.
>25.
53 (SBI C.
>29.
6 (SBI) >75.
98 (SBI N.
>81.
71 (SBI Z.
yuNg/mL (Figure .
Among them, 2-aminobe nzothiazoles based ligand was found to be low IC50 values when compared to the 75.
98 (SBI N.
71 (SBI Z.
for This is due to the presence of imine, hydroxyl, methyl, acetamide, thiazole and benzene ring in the free ligand.
The metal complexes and ligand was readily bind with DNA base and cause replication and transcription process as a result destruction of cancer cell (Aslan et al.
, 2020.
Shiju et al.
, 2.
A 2025 The Authors.
Moreover, metal complexes and free ligand made strong hydrogen bonding was increased as result higher cytotoxic activity (Deswal et al.
, 2.
The microscopic analysis was shown morphological damage and drastically decreased cell density which cause cytotoxicity.
Further, we have compared the IC50 value of standard drug Paclitaxel and synthesized metal complex for DU145 cell line.
The standard drug Paclitaxel has exhibited .
16 A 0.
(Deswal et al.
, 2.
excellent anticancer activity compared to the synthesized metal complex and shown less potent against DU145 cell line.
According to the earlier literature report (Abd-Elzaher et al.
, the SAR of the metal complexes was assessed.
The synthesized transition metal complexes having different metal atom coordinated to the benzothiazole ligand.
The obtained metal complexes and Schiff base ligand was active against DU145 cancer cell line.
The order of IC50 value of metal complexes and ligands are 16.
21 (SBI Co (II)) >25.
53 (SBI Cu (II)) >29.
6 (SBI) >75.
98 (SBI Ni (II)) >81.
71 (SBI Zn (II)) yuNg/mL.
Among them.
Co (II) complex has more potent against DU145 cancer cell line in Figure 10.
Meanwhile.
Ni and Zn complexes are less effective when compared the other metal complexes and ligand, this is due to their high lipophilicity Page 1126 of 1129 Kavitha et.
Science and Technology Indonesia, 10 .
1120-1129 Figure 9.
IC50 Value of Various Concentrations of Metal Complexes .
SBI-Co .
SBI-Ni .
SBI-Cu .
SBI-Zn and .
SBI
CONCLUSIONS
Figure 10.
Schematic llustration of Structure-Activity Relationship of Transition Metal Complex In conclusion, the prepared benzothiazole ligand and square planner complexes was confirmed by using spectroscopic methods.
The cytotoxic activity of four transition metal complexes (Co.
Ni.
Cu, and Z.
against the DU145 cancer cell line was subsequently investigated.
Co complex has more potential against DU145 carcinoma cell line, according to their IC50 values .
21 (SBI Co (II)) >25.
53 (SBI Cu (II)) >29.
6 (SBI)
>75.
98 (SBI Ni (II)) >81.
71 (SBI Zn (II)) yuNg/mL).
Co complex has more potential against DU145 cancer line.
ACKNOWLEDGMENT
(Devi et al.
, 2.
The results are good agreement with the previous literature report.
A 2025 The Authors.
The authors have gratefully acknowledged to Dr.
Gnanavel.
Chemkovil.
Small Industries Development Corporation (SIDC O) in Mettur Dam.
Salem (DT).
India for their support and Page 1127 of 1129 Kavitha et.
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