






























East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, Issue. 1, 42-51 
 

 

 

 

*Corresponding author: 

  Email: haftish1@gmail.com,  251 926046602 https://dx.doi.org/10.4314/eajbcs.v4i1.4S 

 
 

 

 

Synthesis, Characterization and Antibacterial activity of Benzimidazole Derivatives and their 

Cu (ii), Ni (ii) and Co (ii) complexes 

 

Haftom Welderufael*, Dagne Addisu Kure, Endalkachew Asefa Moges, Lelisa File, Salah Hamza 

Sherif  

Department of Chemistry, Hawassa University, Hawassa, Ethiopia 

 

 

KEYWORDS:  

Antibacterial;  

Benzimidazole; 

Metal complex;  

Schiff base 

 

 

 

 

 

 

 

 

 

 

 

ABSTRACT 

Benzimidazole is one of the privileged nitrogen-containing heterocyclic compounds, 

which is found in many bioactive compounds, benzimidazole and its derivatives have 

evolved as an important heterocyclic system due to their potency in a wide range of 

biologically active compounds like anthelmintic, antibacterial, antifungals, anti-

inflammatory, antiviral, and so on. Derivatives of 1-arylsulfonylbenzimidazole and their 

respective Cu (II), Ni (II) and Co (II) complexes were successfully synthesized. The 

structures of all the synthesized ligands were confirmed by using IR, UV-Visible, 1H 

NMR, and 13C NMR spectroscopy. The Cu (II), Ni (II) and Co (II) complexes were 

confirmed by using IR and VU-Visible spectra. The IR spectra of ligands and its metal 

complexes imply that the benzimidazol derivative ligands behave as basic bidentate 

ligands coordination through the azomethine nitrogen and oxygen atom. In-vitro 

antibacterial activity of all the synthesized ligands and their metal complexes were 

evaluated by using disc diffusion method against K. pneumoniae, E. coli, and S. aureus 

bacterial species .The tested compounds and metal complexes exhibited from good to 

excellent activity (zone of inhibition (ZI) ranged 10 mm to 23 mm). Compound BIL1 

exhibited better activity than the standard drug against E. coli (ZI of 15 mm) and K. 

pneumoniae (ZI of 5 mm) compared with gentamycin ((ZI of 15mm). Complex CoC 

exhibited better activity against S. aureus (ZI of 23 mm) compared with gentamicine  (ZI 

value of 21 mm). This compound is a good starting point to develop new drug for 

treating pathogenic diseases. Therefore, synthesis of more analogue were recommended 

for further discovery of a new drug candidate.  

 

INTRODUCTION 

Microbial resistance is one of the critical 

public health issues and the greatest 

challenges of the twenty-first century 

(Marinescu, 2021) especially as increasing 

numbers of strains are becoming resistant to 

multiple antimicrobial agents, with some 

bacteria now being resistant to all available 

antibiotics, there is an pressing need to 

develop new drugs with novel mechanisms of 

action (Fatmah et al., 2015). Nitrogen-

heterocycles play a vital role in medicinal 

chemistry and they have been intensively used 

as scaffolds for drug development, among 

nitrogen containing heterocyclic compounds, 

benzimidazole is continuously drawing the 

interest of many researchers for the 

East African Journal of Biophysical and Computational Sciences 

Journal homepage : https://journals.hu.edu.et/hu-journals/index.php/eajbcs 
 

Hawassa University

College of Natural & Computational Sciences

Year 2021

Volume xx No xx

 

 
Research article

https://dx.doi.org/10.4314/eajbcs.v4i1.4S


East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

43 

development of newer drug moiety 

(Majumder et al., 2013). 

Benzimidazole derivatives are known to 

possess varied biological activities, substituted 

benzimidazole derivatives have been reported 

to possess antimicrobial (Ansari et al., 2009; 

Özkay et al., 2010; Shaharyar et al., 2017), 

anti-inflammatory (Mariappan et al., 2015; 

Achar et al., 2017), and antiviral (Zou et al., 

1996; S. Hirashima et al., 2006; Bhagdev, K. 

and Sarkar, 2021), anticancer (Błaszczak-S´ et 

al., 2014; Sharma et al., 2017; Ting-Ting et al, 

2018) activities. The structural similarity of 

the benzimidazole moiety to naturally 

occurring nucleotides makes it a valuable drug 

scaffold in medicinal chemistry. The strong 

link between the benzimidazole core and a 

wide range of biological activities is well-

documented and established in the literature. 

Benzimidazole derivatives have also been 

used as good ligands for transition metal ions 

due to the large conjugated pi-system and the 

azomethine nitrogen which can positively 

affect the structures of the complexes (Galal et 

al., 2010). 

Due to their potent biological activity, metal 

complexes with aromatic Schiff base ligands, 

particularly those based on imidazoles, have 

gained considerable interest in recent years 

(Kumaravel et al., 2017). The biological 

activities of several metal complexes with 

benzimidazole ligands have been created and 

investigated (Horacio et al., 2008; Kopel et 

al., 2015; Ashraf et al., 2016; Kumaravel and 

Raman 2017). 

In this paper, the synthesis and antibacterial 

activity investigations of benzimidazole 

derivatives and their metal complex against K. 

pneumonia, E. coli, and S. aureus bacterial 

strains were presented. These bacteria were 

selected on the basis that E. coli known to 

cause Urinary tract infections,  K. pneumoniae 

know to be the causative agent of pneumonia 

and S. aureus is multi drug resistant (Abioye 

et al., 2013). Therefore, the objective of this 

study was to compare the activity of the 

ligands with their metal complexes. 

MATERIALS AND METHODS  

All reagents and solvents were of analytical 

grade and used as received. Reaction mixtures 

were monitored via thin-layer chromatography 

(TLC) on silica gel plates. Column 

chromatography employing silica gel (100–

200 mesh) was primarily used for purification 

of the intended products. Melting points were 

determined using open capillary tubes and are 

reported uncorrected. Infrared (IR) spectra 

were collected on an FT-IR Bruker Alpha 

spectrometer. Nuclear magnetic resonance 

(NMR) spectra were acquired using a Bruker 

Advance NMR spectrometer operating at 400 

MHz, with tetramethylsilane (TMS) as the 

internal standard. 

Chemistry  

The benzimidazole derivatives was prepared as 

outlined in scheme 1, the intermediate, 2-

substituted benzimidazole was prepared by 

refluxing o-phenylendiamine with appropriately 

substituted benzaldehyde in Dimethyl 

formamide (DMF) in the occurrence of NaHSO4 

as a catalyst, the benzene sulphonyl substituted 

compounds were prepared by stirring 2-

substituted benzimidazole derivatives with 

benzene sulphonyl chloride at room temperature 

in acetone in the presence of sodium carbonate.  



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

44 

 

IN1, R1 = OCH3,  IN2, R1= H; BIL1, R2 = OCH3, 

BIL2, R2 = H 

SCHEME 1: reagent and condition: a) 

NaHSO3, DMF, reflux 90-100oC; b) K2CO3 

acetone, RT     

Synthesis  

Synthesis of 2-(1H-benzo[d]imidazol-2-yl)-6-

methoxyphenol(IN1) 

A mixture of o-phenylendiamine (1.09g, 

10mmol) and (1.248g, 10mmol) sodium 

hydrogen sulphite were dissolved in 15 mL 

dimethyl formamide (DMF) stirred at room 

temperature for 30min, to this solution (1.52g, 

10mmol) 2-o-vanillin were added, the mixture 

was refluxed for about 6hr at 90oC-100oC, the 

development of the reaction was regulated by 

TLC. At the end of the reaction, the reaction 

mixture was cooled and extracted with ethyl 

acetate. The organic layer was separated, dried 

over anhydrous Na₂SO₄, and concentrated 

under reduced pressure. The resulting material 

was purified by column chromatography using 

a 9:1 mixture of hexane and ethyl acetate. 

 

Synthesis of 2-(1H-benzo[d]imidazol-2-yl) 

phenol (IN2) 

A mixture of o-phenylendiamine (0.54g, 

5mmol) and (0.624g, 5mmol) of sodium 

hydrogen sulphite were dissolved in 15 mL 

dimethyl formamide (DMF) stirred at room 

temperature for 30min, to this mixture 

(0.605g, 5mmol) salisaldehyde were added 

and the mixture  was refluxed for about 6hrs. 

at 90oC-100oC,the progress of the reaction was 

regulated by TLC. At the end of the reaction, 

the reaction mixture was cooled and extracted 

with ethyl acetate. The organic phase was 

harvested and dried over anhydrous Na2SO4; 

the solvent used was removed under reduced 

pressure recrystallized from methanol. 

Synthesis of N-benzenesulfonyl-2-(1H-

benzo[d]imidazol-2-yl)-6-methoxyphenol 

(BIL1) 

2-(1H-benzo[d]imidazol-2-yl)-6-methoxy 

phenol (IN1) (0.38g, 1.77mmol) were 

dissolved in 10 mL acetone and (0.614g, 

4.429mmol) K2CO3 were added and stirred at 

room temperature for 30min, then 0.3 mL of 

benzene sulfonyl chloride was added drop 

wise to the mixture and refluxed for 6 hours, 

The reaction's progress was followed by thin-

layer chromatography (TLC). Once complete, 

the reaction mixture was partitioned between 

water and ethyl acetate. The organic phase 

was collected, dried over anhydrous sodium 

sulfate (Na₂SO₄), and concentrated in vacuo. 

The resulting product was then subjected to 

column chromatography, using a 9:1 mixture 

of hexane and ethyl acetate as the mobile 

phase. 

Synthesis of N-benzenesulfonyl-2-(1H-

benzo[d]imidazol-2-yl) phenol (BIL2) 

2-(1H-benzo[d]imidazol-2-yl)phenol(IN2) 

(1.15g, 5.4 mmol) was dissolved in 10 mL of 

acetone,K2CO3(1.8g, 13.5mmol) were added 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

45 

and stirred at room temperature for 30min, 0.8 

mL of benzene sulfonyl chloride were added 

to the mixture drop wise and refluxed for 6 

hours, The progress of the reaction was 

monitored by TLC. At the end of the reaction, 

the reaction mixture was cooled and extracted 

with ethyl acetate. The organic phase was 

collected and dried on anhydrous Na2SO4 and 

crystallized under abridged pressure. The 

product was then further purified by column 

chromatography. 

Synthesis and Characterization of metal 

complexes of BIL1 

A methanolic solution of ligand BIL1 (0.38 g, 

0.5 mmol, in 10 mL) was combined with a 

separate methanolic solution (5 mL) of either 

Cu(CH₃COO)₂·H₂O, Ni(CH₃COO)₂·4H₂O, or 

CuCl₂·6H₂O (1 mmol each). The combined 

solutions were refluxed for 8 hours, with the 

reaction being monitored by thin layer 

chromatography (TLC). After allowing the 

mixture to cool in an ice bath, the precipitate 

was collected by filtration and washed with 

dichloromethane. The solid was dried under 

vacuum overnight, and then recrystallized 

from methanol.  

Antibacterial activities   

Culture media and disk preparation 

Nutrient agar, Muller Hinton agar and 

Nutrient broth were prepared according to the 

manufacturer instruction in which the 

prepared media was autoclaved at 121oC for 

15 minutes. Then the prepared culture media 

was checked for the sterility for 24 hours at 37 
oC. For quality control, strains of 

Staphylococcus aureus (S. aureus), 

Escherichia coli (E. coli) and Klebsiella 

pneumonia (K. pneumonia), which were 

obtained from the College of medicine and 

health science of Hawassa University, known 

American type culture collection committee 

(ATCC) were used to perform the 

antibacterial activities of the agents. Whatman 

filter paper 41 is used to prepare a disk of 

5mm diameter using manual paper punching. 

Preparation of chemical slution and media 

for the antibacterial activity 

By using analytical balance, a 0.005g of each 

chemical powder was added to 15µl dimethyl 

sulphoxide (DMSO) and mixed to form a 

homogenous solution. A 5µl of the solution 

was added to the sterile disk prepared before 

using sterile micropipette. The aforementioned 

bacterial strains (meant for quality control) 

were inoculated on sterile nutrient agar plates 

using sterile loop. The streaked plates were 

incubated for 24 hours at 37oC. A 3 to 5 

colonies were picked with sterile loop and 

suspended in 5 mL nutrient broth to form 

standards. The culture suspension was then 

inoculated on sterile Muller Hinton agar plate 

using sterile cotton swab in three directions to 

get uniform inoculum. The antibiograms 

profiles of the test organisms to the control 

antibiotic were checked. Then an autoclaved 

disks with a control gentamicin and solution 

impregnated disks were carefully positioned 

on the plate and incubated for 24 hours at 

37oC. The unique ID number of each disk was 

mentioned with permanent marker on the back 

of the Petri dishes. After incubation the 

diameter of the zone of inhibition was 

measured using ruler. The result was given in 

(table 1) 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

46 

RESULT AND DISCUSSION  

Characterization 

Characterization of 2-(1H-benzo[d]imidazol-

2-yl)-6-methoxyphenol (IN1) 

Light red solid; Yield:76.1%;Mp:195-197 oC; 

IR(KBr, Cm-1): 3394(-NH), 3240(-OH), 

3047(C-H, aromatic), 2854(C-H, methyl), 

1593(C=N); 1H-NMR (DMSO-d6,400MHz): 

H 13.12(s, 1H,-OH), 7.91-789(m, 2H, Ar-H), 

7.73-763(m, 2H, Ar-H), 7.42-7.37(m, 2H, Ar-

H), 7.26-7.25(m, 1H, Ar-H), 5.00(s,1H,-NH), 

3.7(s,3H,OCH3); 
13C-NMR (DMSO-d6, 

100MHz): C 149.2, 147.1, 142.6, 137.0, 

123.5, 122.8, 121.1, 120.1, 114.3, 111.0, 42.7 

Electronic spectra of compound IN1 

The UV-Vis spectrum of the IN1 compound 

was recorded in DMSO. The electronic 

absorption spectrum of the ligand showed 

bands at 304 nm, attributed to a π-π* 

transition of the –C=C– bond; 382 nm, 

corresponding to an n-π* transition; and 497 

nm, assigned to an n-π* transition of the 

azomethine chromophore (–C=N–). 

Characterization of N-benzenesulfonyl-2-

(1H-benzo[d]imidazol-2-yl)-6-

methoxypheno1 (BIL1) 

Light red solid; Yield:68.0%, Mp:230-232oC; 

IR(KBr, Cm-1): 3210 (-OH), 2923(C-H, 

aromatic), 2854(C-H), 1458(C=N), 

1377(O=S=O); 1HNMR(DMSO-d6,400MHZ): 

H 13.2 (s,1H,OH), 7.9(d, J= 8.4Hz,2H), 

7.7(m, 2H), 7.6(d, J=7.4Hz,2H), 7.5(m,1H), 

7.4(d, J=6.5Hz,1H), 7.3(m,2H), 7.1(d, 

J=7.65Hz,1H),  6.9(m,1H,), 3.7(s,3H, 

OCH3);
13C-NMR (DMSO-d6, 100MHz) C 

153.1, 147.6, 136.0, 133.8, 129.8, 128.3, 

126.9, 126.4, 123.0, 122.7, 122.5, 115.6, 

115.0, 56.4  

Electronic spectra of compound BIL1 

The UV/Visible spectral for BIL1 compound 

recorded in DMSO, the electronic absorption 

spectrum of the ligands showed band at 

302nm attributed to –C=C-, * transitin, 

the band around 382nm and 495nm is because 

of n * transition of the(-C=N-) azomethine 

chromophore.  

Characterization of N-benzenesulfonyl-2-

(1H-benzo[d]imidazol-2-yl) phenol (BIL2) 

Yellow solid; Yield:71.2 %, Mp:196-198 oC, 

IR(KBr, Cm-1): 3232 (O-H), 2954(C-H, 

aromatic), 1458(C=N),1176 (C-O) strong 

band at1377 (O=S=O); 1H-NMR(400MHz, 

DMSO-d6) H:13.15(s, 1H, -OH), 7.74-7.61(m, 

5H, Ar-H), 7.29-7.20(m, 4H, Ar-H), 7.08-7.06 

(m, 2H, Ar-H), 6.97-6.91(m, 2H, Ar-H); 13C-

NMR (100 MHz,DMSO-d6) C:115.3, 118.1, 

119.5, 121.3, 121.52, 121.94, 122.64, 123.0, 

123.33, 128.9, 131.1, 137.9, 138.9, 141.5, 

155.3 

Characterization of Cu(II) complexes of 

BIL1(CuC) 

The product was obtained as a light brown 

solid with a 74.5% yield and a melting point 

of 214-216 °C. The IR spectrum (KBr, cm⁻¹) 

showed characteristic peaks at 3394 (O-H 

stretching of water), 2923-2858 (C-H), 1604 

(C=N), and 1377 (S=O). The C-O stretch, 

observed at a higher frequency in the Cu (II) 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

47 

complexes compared to the free ligands, 

suggests logical coordination through the 

deprotonated phenolic-O. This is supported by 

the disappearance of the weak phenolic OH 

band in the complex spectra. Far-infrared 

bands corresponding to M-O bonds, including 

a band at 1188 cm⁻¹ assigned to the (Cu-O) 

bond in the complexes, further corroborate the 

proposed coordination mode of the Schiff base 

ligands. 

The Uv/visible spectra recorded in DMSO, the 

electronic absorption spectrum of the ligands 

showed band at 301nmattributed to * 

transition of –C=C-, the band around 382nm 

and 502nmis due to n * transition of the (-

C=N-) azmethine chrmphre.  

S N
N

O

O

O OCH3

N

N
S

O
OCH3

O

O

Cu OAccAO H2O

 

Proposed structure of Cu(II) complex of 

BIL1(CuC) 

Characterization of Ni(II) complexes of 

BIL1(NiC) 

Pale green solid, yield 76.9%, Mp: 220-222oC; 

IR (KBr, Cm−1):3240 (O-H stretching of 

water), 2923-2858(C-H, stretching), 

1604(C=N), 1461 (C-O), 1377 (S=O). The C-

O stretch of the free ligands was observed at a 

higher frequency in the spectra of the Ni(II) 

complexes, suggesting coordination of the 

Schiff base ligands through the deprotonated 

phenolic–O, This was substantiated by the 

disappearance of the weak phenolic OH band 

in the spectra of the complexes. The mode of 

coordination of the Schiff base ligands was 

further corroborated by the appearance of 

bands in the far-infrared spectra of the 

complexes due to the M-O bonds. The new 

bands in the low frequency region 510 and 

440 are due to the formation of (M–O) and 

(M–N) vibrations respectively. 

Electronic spectra of compound NiC 

The Uv/visible spectral for compound NiC are 

recorded in DMSO the data are presented in 

the electronic absorption spectrum revealed 

band at 302nm attributed to *transition 

of (–C=C) ,the band around 382nm and 

499nm is due to *and n * transition of 

the (-C=N-) azomethine chromophore.  

S N
N

O

O

O OCH3

N

N
S

O
OCH3

O

O

OAccAO 4H2ONi

 

Proposed structure of Ni(II) complexof BIL1(NiC) 

Characterization of Co (II) complexes of 

BIL1 (CoC) 

Yellow solid, Yield 88.8%, Mp:210-212oC, 

The IR stretching (KBr, v in cm-1) spectral 

information for compound CoC, showed 

distinguishing medium band at 3394cm-

confirmed the presence of O-H stretching of 

water. Strong band at 2923-2858cm-1 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

48 

guaranteed the presence of C-H stretching of 

aromatic. A medium band at 1604cm-1 

confirmed the availability of C=N stretching 

of azomethine. A medium narrow band at 

1461cm-1confirmed the presence of C-O 

stretching of aromatic. A medium narrow 

band at 1677cm-1 confirmed the presence of 

C=C stretching aromatic and the strong band 

at 1377cm-1 confirmed the presence of two 

S=O stretching of benzene sulfonyl. A higher 

C-O stretching frequency was observed in the 

infrared spectra of the Co(II) complexes 

compared to the free ligands, which indicates 

coordination of the Schiff base ligands via the 

deprotonated phenolic oxygen. The conclusion 

made based on these findings was supported 

by the absence of the weak phenolic O-H band 

in the complex spectra. Moreover, the far-

infrared spectra of the complexes showed 

bands that can be assigned to M-O vibrations, 

including one at 1130 cm⁻¹ corresponding to 

the Co-O bond. 

Electronic spectra of compound CoC 

The Uv/visible spectra for compound CoC 

were noted in DMSO, the electronic 

absorption spectrum of the ligands showed 

band at 267nm associated with –C=C- , * 

transition, the band around 302nm and 319nm 

is because of *and n * transition of 

the-C=N-azomethine chromophore. No 

spectral bands were found below 300nm 

which supports octahedral geometry. 

S N
N

O

O

O OCH3

N

N
S

O
OCH3

O

O

Cl 6H2OCoCl

 

Proposed structure of Co (II) complex of 

BIL1(CoC) 

Characterization of copper (II) complexes of 

BIL2 (CuC2) 

The light brown solid, CuC2, was obtained 

with an 86.7% yield and a melting point of 

160-162 °C. The IR spectrum (KBr, cm⁻¹) 

exhibited a medium band at 3363 cm⁻¹ 

indicative of O-H stretching from water, 

strong bands at 2923-2858 cm⁻¹ due to 

aromatic C-H stretching, a medium band at 

1612 cm⁻¹ consistent with C=N stretching in 

the azomethine, a medium narrow band at 

1461 cm⁻¹ corresponding to aromatic C-O 

stretching, a medium narrow band at 1917 

cm⁻¹ assigned to aromatic C=C stretching, and 

a strong band at 1377 cm⁻¹ suggesting two 

S=O stretching in the benzene sulfonyl group. 

A shift to higher frequency in the C-O 

stretching band was observed for the Co(II) 

complexes compared to the free ligands, 

indicating coordination of the Schiff base 

ligands through deprotonated phenolic 

oxygen. This observation was substantiated by 

the absence of the characteristic phenolic OH 

band in the complex spectra. Additionally, the 

far-infrared spectra of the complexes exhibited 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

49 

bands that can be attributed to M-O vibrations, 

including one at 1170 cm⁻¹ corresponding to 

the Co-O bond. 

Electronic spectra of compoundCuC2 

The Uv/visible spectral for compound CuC2 

are recorded in DMSO. The data are offered in 

the electronic absorption spectrum of the 

ligands showed band at 274nm (36496cm-1) 

attributed to –C=C-, *transition the band 

around 300nm and 332nm due to *and 

n *transition of the (-C=N-) azomethine 

chromophore. No spectral bands were found 

below 10000cm-1 which supports octahedral 

geometry. 

S N
N

O

O

O

N

N
S

O

O

O

OAccAO H2O
Cu

 

Proposed structure of Cu(II) complex of BIL2 

(CuC2). 

Table-1: In-vitro antibacterial activity values of the synthesized benzimidazol derivatives and 

their Cu(II), Ni(II) and Co(II) complexes 

 

The synthesized benzimidazol derivative and 

Cu(II), Ni(II) and Co(II) complexes were 

tested for in-vitro antibacterial activity against 

E. coli, S. aureus and K. pneumonia. 

Gentamicin was used as standard antibacterial 

drug. The zone of inhibition values clearly 

showed that all the compounds exhibited a 

varied range 5-23mm (table 1) against all the 

tested bacterial strains. Compounds IN, BIL2 

and CuC2 had less activity against E. coli and 

S. aureus.  Compounds NiC and CuC showed 

moderate antibacterial activity against E. coli 

and S. aureus. Compound BIL1 exhibited 

better activity against E. coli (15mm zone of 

 

Entry  

 

Compounds  

                 Zone of inhibition (in mm) 

E. coli S. aureus K. pneumonia 

1 IN1 5 10 5 

2 BIL 1 15 18 8 

3 BIL2 5 7 5 

4 CuC 

[Cu(BIL1)2(OAc)2].H2O 

11 18 8 

5 NiC 

[Ni(BIL1)2(OAc)2].4H2O 

10 20 6 

6 CoC 

[Co(BIL1)2(Cl)2].6H2O 

12 23 11 

7 CuC2 

[Cu(BIL2)2(OAc)2].H2O 

5 5 5 

Standard Gentamycin 14 21 5 



East Afr. J. Biophys. Comput. Sci. (2023), Vol. 4, No. 1, 42-51 
 

50 

inhibition) compared to standard (14mm zone 

of inhibition) but moderate activity against S. 

aureus; compound CoC exhibited better 

activity against S. aureus (23mm zone of 

inhibition) compared to standard (21mm zone 

of inhibition) but moderate activity against E. 

coli.  

CONCLUSION 

All the synthesized compounds in this study 

showed better activity against K. pneumonia 

compared to standard. Comparing the two 

benzimidazole derivatives BIL1 and BIL2; 

BIL1 showed better activity against all the 

tested bacterial strain, structurally the two 

compounds are differ by the presence of 

methoxy substituent at 3 position of phenyl 

ring, it can be concluded that the dramatic 

increase in the activity is due to the presence 

of this substituent. This compound is a good 

starting point to develop new drug for treating 

pathogenic diseases. Therefore, synthesis of 

more analogue were recommended for further 

discovery of a new drug candidate. 

Acknowledgement  

The authors thank Addis Ababa University for 

running the NMR, IR, and UV-vis spectra and 

Hawassa University for providing research 

funding.  

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	EAJBCS__Volume_4_Issue_1_Article 4_ Haftom et al_ Synthesis, Characterization and Antibacterial activity of Benzimidazole.pdf (p.48-57)
	INTRODUCTION
	EXTENSION OF THE MODIFIED MODEL INTO AN OPTIMAL CONTROL
	Optimal protection and hospitalization using modified model
	Existence of an optimal control
	The Hamiltonian and optimality system

	Numerical simulations of optimal control problem
	Optimal control comparisons and strategies

	CONCLUSION
	INTRODUCTION
	INTRODUCTION
	INTRODUCTION
	EXTENSION OF THE MODIFIED MODEL INTO AN OPTIMAL CONTROL
	Optimal protection and hospitalization using modified model
	Existence of an optimal control
	The Hamiltonian and optimality system

	Numerical simulations of optimal control problem
	Optimal control comparisons and strategies

	CONCLUSION
	INTRODUCTION
	INTRODUCTION

