Design, synthesis, antibacterial and antifungal activity of novel 2-[(E)-2-aryl-1-ethenyl]-3-(2-sulfanyl-1H-benzo[d]imidazole-5-yl)-3, 4-dihydro-4-quinolinones

Article abstract of DOI:10.1155/2012/795698

The novel 2-[ (E)- 2-aryl-1-ethenyl]-3- (2-sulfanyl-1H-benzo[d]imidazole-5- yl)-3, 4- dihydro-4-quinolinones (4a-j) analogs were synthesized by Knoevenagel condensation of a solution of 2-methyl-3- (2-sulfanyl-1H-benzo[d]imidazole-5-yl) -3, 4-dihydro-4-qu

Full text of DOI:10.1155/2012/795698

ISSN: 0973-4945; CODEN ECJHAO
E-Journal of Chemistry
http://www.ejchem.net
2012, 9(3), 1481-1489
Design, Synthesis, Antibacterial and Antifungal
Activity of Novel 2-[(E)- 2-aryl-1-ethenyl]-3-(2-
sulfanyl-1H-benzo[d]imidazole-5-yl)-3,4- dihydro-4-
quinolinones
ANISETTI RAVINDER NATH* AND MALLADI SRINIVAS REDDY§
University College of Technology, Osmania University, Hyderabad- 500007, (A.P.),India.
§St.Peter’s Institute of Pharmaceutical Sciences, Vidhyanagar, Hanamkonda, Warangal-
506001 (A.P.), India.
msr.srinivas@gmail.com
Received26-Nov-2011; Accepted18-Jan-2012
Abstract:
The
novel
2-[(E)-
2-aryl-1-ethenyl]-3-(2-sulfanyl-1H-
benzo[d]imidazole-5-yl)-3,4- dihydro-4-quinolinones (4a-j) analogs were
synthesized by Knoevenagel condensation of a solution of 2-methyl-3-(2-
sulfanyl-1H-benzo[d]imidazole-5-yl)-3,4-dihydro-4-quinazolinone (3) with
aromatic aldehyde in presence of catalytic amount of piperidine . Compounds
(4a-j) showed significant biological activity against all the standard strains. All the
1
synthesized compounds were characterized on the basis of their IR, H NMR,
MASS spectroscopic data and elemental analyses. All the compounds have
been tested for antimicrobial and antifungal activity by the cup-plate method.
Keywords: Knoevenagel condensation, 2-Mercaptobenzimidazole, 3,4-dihydro-4-quinolinones,
Antibacterial activity and Antifungal activity.
Introduction
In the present century, due to the advancement and changes in the culture and life style, new
diseases are being existed among the human population which indicates that the search for
better drugs is still necessary. Discovery of new drugs that is therapeutically useful and goes
into clinics is a lifetime dream for medicinal chemist. Structural activity relationships of
imidazole containing structure have dominated investigations in medicinal chemistry for
active biological entities1. Many benzimidazole derivatives belong to a crucial structural
motif that is seen in many pharmaceutically and biologically interesting molecules. They
have been intensively used in medicinal chemistry as drugs such as antihistaminic2, anti
ulcerative3, antihelmentic4 and antipsychotic5. Some of their analogous shows an array of
biological activities, including non-nucleosides HIV-1 reverse transcriptase inhibitor6 and
they are selective inhibitors of cyclooxy genase COX-27. Several benzimidazoles have been

1482 ANISETTI RAVINDER NATH
reported as antiviral8, anticoagulant9, anti-inflammatory10, antibacterial11, and anticancer
agents12. Quinazoline-4-(3H)-ones have been reported to possess a wide range of biological
activities such as anti-microbial 13-17, analgesic 18,19, anti-inflammatory20, anti-convulsant21,22
,
anti-cancer 23,24, anti-tubercular25,26,anti-malarial27, and antiviral28,29 activities. Inspired with
the biological profile of benzimidazole and quinazoline-4-(3H)-one, and their increasing
importance in pharmaceutical and biological fields, it was thought worthwhile, to synthesize
the title compounds with view to obtain certain new entities with two active pharmacophores
in a single molecule frame work in order to prepare molecules having with potentially
enhanced biological activities and to have then evaluated for their antimicrobial activity. On
the other hand, to the best of our knowledge previously there is no report on the synthesis of
novel
2-[(E)-2-aryl-1-ethenyl]-3-[2-sulfanyl-1H-benzo[d]imidazole-5-yl]-3,4-dihydro-4-
quinolinones.
The synthesis of compounds 2, 3 and 4 was accomplished by the synthetic sequence shown
in Scheme 1. The reaction of 2-methyl benzoxazin -4-one (1) with 5-amino-1H –
benzo[d]imidazole -2-thiol (2) in ethanol furnished 2-methyl-3-(2-sulfanyl-1H-benzo [d]
imidazole-5-yl)-3,4-dihydro-4-quinazolinones(3). Compounds
3
on Knoevenagel
condensation with substituted aromatic aldehydes in presences of piperidine in ethanol
afforded novel 2-[(E)-2-aryl-1-ethenyl]-3-[2-sulfanyl-1H-benzo [d] imidazole-5-yl]-3,4-
dihydro-4-quinolinones(4).The structures of products 3 and 4 have been elucidated on the
1
basis of spectral (IR, HNMR, and MS) and micro analytical data. Compound 3 displayed
characteristic absorption bands in the IR spectra around 1700, 1619 and 699 cm-1due to
C=O, C=N, and C-S functional groups, respectively confirming the formation of sulfanyl
1
benzo [d] imidazole-5-yl-dihydro-4-quinazolinone. HNMR spectra of 3 exhibited a sharp
singlet around δ 0.91, 3.54 due to CH3, SH and 12.01 due to benzimidazole NH. Mass
spectrum of the product 3, agrees well with the structure, which showed a molecular ion
peak at [M]+ at m/z 308. The 1H NMR spectrum of 4 displayed two distinct doublets around
δ 6.6 and 6.8 due to styryl =CH protons, confirming the Knoevenagel condensation. The
mass spectrum of 4 confirmed the structure by exhibiting the molecular ion peak at [M]+ at
m/z 396. Elemental analyses are satisfactory and confirmed elemental composition and
purity of the newly synthesized compounds 4.
H
N
O
O
SH
H
N
ethanol
O
N
N
+
SH
stirring /
N
N
CH3
H2N
N
CH3
2
1
3
piperidine
ethanol /
Ar- CHO
O
H
N
SH
N
N
N
Ar
4a-j
Scheme 1. Synthesis of 2-((E)-2-aryl-1-ethenyl]-3-(2-sulfanyl-1H-benzo [d] imidazole-5-
yl)-3,4-dihydro-4-quinolinones.

Design, Synthesis, Antibacterial and Antifungal Activity 1483
Experimental
Melting points were recorded on an Electrothermal type 9100 melting point apparatus and
are Uncorrected. The IR spectra were recorded on Nicolet impact 410 FTIR
spectrophotometer using KBr pellets.1HNMR spectra were recorded on bruker Ac 300 MHz
instrument using CDCl3 and with TMS as the internal standard. The mass spectra were
obtained on a varian MATCH-7 instrument at 70eV Elemental analyses was carried out
using Perkin-Elmer 240C CHN-analyzer.
Synthesis of 2-methyl -3-(2-sulfanyl-1H-benzo [d] imidazole-5-yl)-3,4-dihydro-4-
quinazolinone (3)––General Procedure
A mixture of 2-methyl benzoxazin-4-one (1) (0.01 mol) and 5-amino-1H-benzo[d]
imidazole-2-thiol (2) (0.01mol) were taken in ethanol (15 mL). The reaction mixture was
refluxed while stirring for about 2 h. The residue was purified by recrystallization from ethyl
acetate to produce 3. yield 70%, m.p.:185-187oC; Anal. Calcd. for C16H12N4OS (308.36): C,
62.32; H, 3.92; N, 18.17; S, 10.40. Found: C, 62.29; H, 3.94; N, 18.19; S, 10.38. IR (KBr,
1
cm-)1: 1700 (C=O), 1619 (C=N), 699 (C-S); H NMR (300MHz, CDCl3) δ: 0.91 (s, 3H,
CH3), 3.54 (s, 1H, SH), 6.31-7.54 (m, 7H, ArH), 12.01 (s, 1H, benzimidazole-NH D2O
exchangeable).EI-MS [M]+ at m/z 308.
2-((E)-2-phenyl-1-ethenyl)-3-(2-sulfanyl-1H-benzo [d] imidazole-5-yl)-3,4- dihydro-4-
quinazolinone (4a-j ––General Procedure
To
a
solution of 2-methyl-3-(2-sulfanyl-1H-benzo[d]imidazole-5-yl)-3,4-dihydro-4-
quinazolinone (3) (0.01mol) in ethanol (25 mL), aromatic aldehyde (0.01mol) was added
with catalytic amount of piperidine (0.5 mL) and the contents were refluxed for 3 h. After
cooling, the contents were poured into crushed ice. The resulting solid was washed with
distilled water, filtered, dried in vacuum and recrystallized from ethyl acetate (Scheme 1).
Similarly remaining compounds (4a-j) was prepared by above method. The characterization
data of these compounds is described in Tables 1 and 2.
Antibacterial Activity
Antibacterial activity of 4a-j in DMSO was performed by the broth dilution method using
nutrient agar against Gram-negative bacteria Pseudomonas aeruginosa (NCCS2200),
Escherichia Coli (NCCS2065), and Gram-positive bacteria bacillus cereus (NCCS2106),
and Staphylococcus aureus (NCCS2079) at 100µg/mL concentration. The minimum
inhibitory concentration was done by the broth dilution method (30). Cefaclor was used as
standard for comparison. The readymade nutrient broth media (Himedia, 24g) was
suspended in distilled water (100 mL) and heated until it dissolved completely. The medium
and test tubes were autoclaved at a pressure of 15 lb/inc2 for 20 min. A set of sterilized test
tubes with nutrient broth medium was capped with cotton plugs. The test compound was
dissolved in DMSO and a concentration of 250 µg/mL of the test compounds was added in
the first test tube, which was serially diluted. A fixed volume of 0.5 mL of overnight culture
was added in all the test tube which were incubated at 37oC for 24 h. After 24 h, these tubes
were measured for turbidity. Results are given in Table 3.

1484 ANISETTI RAVINDER NATH
Table 1. physical data of compounds 4a-j.
Elemental analysis, %
M.
P
C
H
N
Ar
M.F.
o C
Found Calcd Found Calcd Found Calcd
4a
4b
C6H5
C23H16N4OS
230 70 69.68 69.65
4.07
3.91
3.51
4.05
3.87
3.54
14.13 14.19
13.58 13.53
13.00 13.03
2-
C23H16N4O2S 280 85 66.97 66.99
OHC6H4
4 c 2- ClC6H4 C23H15N4OSCl 270 65 64.11 64.08
4
4- ClC6H4 C23H15N4OSCl 272 68 64.11 64.13
d
3.51
4.25
3.49
4.28
13.00 13.02
13.14 13.18
4-
4 e
C24H18N4O2S 265 65 67.59 67.63
OCH3C6H4
4- N
(CH3)2
C6H4
4 f
C25H21N5OS
C24H18N4OS
210 70 68.32 68.37
230 72 70.22 70.18
4.82
4.42
3.18
3.42
4.83
4.38
3.16
3.46
15.93 15.09
13.65 13.67
11.79 11.74
15.86 15.89
4
g
4-
CH3C6H4
4h 2- BrC6H4 C23H15N4OSBr 285 68 58.11 58.08
4-
4i
C23H15N5O3S 280 78 62.58 62.55
NO2C6H4
4 j 4- BrC6H4 C23H15N4OSBr 284 78 58.11 58.09
3.18
3.20
11.79 11.76

Design, Synthesis, Antibacterial and Antifungal Activity 1485
Table 2. Spectral data of the compounds 4a-j.
MASS
Compd. IR, Cm-1, (KBr)
1H NMR (CDCl3)
(m/z ) M+
3.52 (s, 1H, SH), 6.65(d, J =15.2 Hz,
1H, CH=CH), 6.85-7.86 (m, 12H,
ArH and 1H, CH=CH), 12.10
(1H,benzimidazole-NH D2O
exchangeable)
1710 (C=O), 1605 (C=N),
618 (C-S)
4a
4b
396
3.84 (s, 1H, SH), 6.31 (d, J =
15.2Hz, 1H, CH=CH), 6.93-7.84 (m,
1705 (C=O), 1625 (C=N), 11H, ArH and 1H, CH=CH), 8.43
412
686 (C-S)
(bs, 1H, OH, D2O exchangeable),
11.12 (s, 1H, benzimidazole-NH
D2O exchangeable)
3.62 (s, 1H, SH), 6.58 (d, J =15.2
Hz, 1H, CH=CH), 7.35-7.89 (m,
11H, ArH and 1H, CH=CH),10.5 (s,
1H, benzimidazole-NH,D2O
exchangeable)
1720 (C=O), 1615 (C=N),
695 (C-S)
4 c
4 d
4 e
430
430
426
3.45 (s, 1H, SH), 6.81 (d,
J
=15.2 Hz, 1H, CH=CH), 7.26-8.17
(m, 11H, ArH and 1H, CH=CH),
9.83 (s, 1H, benzimidazole-NH D2O
exchangeable)
3.45 (s, 1H, SH), 3.62 (s, 3H, OCH3),
7.06 (d, J =15.2 Hz, 1H, CH=CH),
7.18-8.18 (m, 11H, ArH and 1H,
CH=CH),10.31 (s, 1H, benzimidazole-
NH D2O exchangeable)
1715 (C=O), 1620 (C=N),
690 (C-S)
1710 (C=O), 1620 (C=N),
665 (C-S)
3.12 (s, 6H, 2NCH3), 3.82 (s, 1H,
SH), 6.72 (d, J =15.2 Hz, 1H,
CH=CH), 7.22-8.14 (m, 11H, ArH
and 1H, CH=CH), 10.25 (s, 1H,
benzimidazole-NH,D2O
exchangeable)
2.8 (s, 3H, Ar-CH3), 3.66 (s, 1H,
SH), 6.80 (d, J =15.2
Hz,1H,CH=CH),7.22-7.85 (m, 11H,
ArH and 1H ,CH=CH),9.85 (s, 1H,
benzimidazole – NH, D2O
exchangeable)
1720 (C=O), 1610 (C=N),
690 (C-S)
4 f
439
410
1680 (C=O), 1615 (C=N),
682 (C-S)
4 g
3.42 (s, 1H, SH), 6.80 (d, J =15.2 Hz,
1H, CH=CH), 7.15-7.93 (m, 11H, ArH 474
and 1H ,CH=CH)
1695 (C=O), 1615 (C=N),
662 (C-S)
4h
4i
4.01 (s,1H,SH), 6.70 (d, J =15.2 Hz,
1H, CH=CH), 7.22-7.80 (m, 11H,
ArH and 1H, CH=CH)
3.85 (s, 1H, SH), 6.72 (d, J =15.2Hz, 1H,
CH=CH),7.15-7.93 (m, 11H, ArH and 1H
, CH=CH)
1675 (C=O), 1610 (C=N),
665 (C-S)
441
474
1675 (C=O), 1618 (C=N),
685 (C-S)
4 j

1486 ANISETTI RAVINDER NATH
Table 3. Antibacterial activity of 4a-j.
Minimum inhibitory concentration
Gram- Positive Gram- Negative
Compound
S.aureus
B.cereus
E.coli
P. aeruginosa
18
17
14
20
21
11
10
14
15
19
17
13
4a
4b
4c
11
16
22
13
11
17
18
11
4d
4e
19
18
16
18
18
13
16
20
4f
4g
15
13
15
19
19
9
16
15
12
19
15
14
17
20
4h
4i
20
22
4j
Cefaclor
a Negative control (DMSO) – no activity. Values are indicated in µg/mL.
Anti fungal Activity
The antifungal activity of 4a-j was performed by the agar cup bioassay method (31) using
clotrimazole as the standard. The compounds were tested for their antifungal activity against
two test organisms, Aspergillus niger (NCCS1196) and Chrysosporium tropicum
(NCCS3474) using the agar cup bioassay method at 100 µg/mL concentration .The
readymade potato dextrose agar media (Himedia, 39g) was suspended in distilled water
(100 mL) and heated until it dissolved completely. The medium and Petri dishes were
autoclaved at a pressure of 15 lb/inc2 for 20 min. The medium poured into sterile Petri
dishes under aseptic conditions in a laminar flow chamber. When the medium in the plates
solidified, 0.5 mL of the (week-old) culture of test organism was inoculated and uniformly
spread over the agar surface with a sterile L-shaped rod. Solutions were prepared by
dissolving plant extract in acetone (100 µg/mL). Agar inoculation cups were scooped out
with 6 mm sterile cork borer and the lids of the dishes were replaced .To each cup, 100
µg/mL of test solution was added. Controls were maintained with acetone and clotrimazole
(100 µg/mL). The treated and the control were kept at room temperature for 72-96 h.
Inhibition zones were measured and the diameter was calculated in millimeters. Three to
four replicates were maintained for each treatment. The results are given in Table 4.

Design, Synthesis, Antibacterial and Antifungal Activity 1487
Table 4. Antifungal activity of 4a-j.
Zone of inhibitory concentration
Compound
A. niger
19
C. tropium
27
45
29
26
45
30
55
19
45
4a
4b
4c
4d
4e
4f
50
18
23
20
15
50
4g
4h
4i
35
21
45
29
40
30
4j
Clotrimazole
aNegative control (acetone) – no activity.
Conclusion
From the antimicrobial screening it was observed that all the compounds exhibited activity
against all organisms employed. The results of antibacterial screening (Table 3) reveal that
compounds 4a-j displayed a better activity and are more active than the standard drug
cefaclor. In series 4, compounds 4c, 4e, and 4i possessing chloro, methoxy and nitro groups
as substitutents on the benzene ring showed a better activity. However the degree of
inhibition varied both with the test compound and with the bacteria used in the present
investigation. In conclusion, almost all the compounds, 4a-j exhibited the maximum activity
by inhibiting the growth of all the four bacteria to a greater extent in comparison with the
standard drug cefaclor. The antibacterial activity of some of these compounds is promising
compared with standard cefaclor, and they can be exploited for the formation of bactericide
after further study. The antifungal activity results (Table 4) indicated that compounds 4a-j
are significant toxic towards the two fungi and they are lethal at 100 µg/mL concentration.
In series 4, compounds 4b, 4g, and 4j exhibited a high antifungal activity which may be due
to the presence of hydroxyl, methyl and bromo substituents on the benzene ring. However
the degree of spore germination inhibited varied with the test compounds as well as with the
fungi. The antifungal activity of these compounds was compared with the standard drug
clotrimazole, and they have a promising activity, when compared with standard drug
clotrimazole, all the series of compounds, 4a-j are highly toxic toward the fungi under

1488 ANISETTI RAVINDER NATH
investigation and they are lethal even at 100 µg/mL concentration in comparison with
standard clotrimazole at the same concentration.
Acknowledgments
The authors are thankful to chairman and principal St.Peter’s Institute of Pharmaceutical
Sciences, Vidhyanagar, Hanamkonda, India, for the facilities and to Director, Indian
Institute of Chemical Technology, Hyderabad, India, for the spectral facility.
References
1. Gribble G W and Gilchrist T L, Progress in Heterocyclic Chemistry : Elsevier, United
Kingdom., 2000, 121.
2. Al-Muhaimeed H S, J. Int. Med. Res., 1997, 25, 175.
3. Richter J E, Am. J.Gastroenterol., 1997, 92, 30.
4. Hazelton J C, Iddon B, Suschitzky H and Woolley L H, Tetrahedron., 1995, 51, 10771.
5. Kyle D, Goehring R R and Shaoo B, WO. 2001039775.
6. Gardiner J M, Loyns C R Burke A, Khan A and Mahmood N, Bioorg. Med. Chem.
Lett., 1995, 5, 1251..
7. Paramashivappa R, Phani Kumar P, Subba Rao P V and Srinivasa Rao A,. Bioorg.
Med. Chem. Lett.,. 2003, 13, 657.
8. Li Y F, Wang G F, Luo Y, Huang W G, Tang W, Feng C L, Shi L P, Ren Y D,
Zuo J P and Lu W, Eur. J. Med. Chem.,. 2007, 42, 1358.
9. Young W B, Sprengeler P, Shrader W D, Li Y, Rai R, Verner E, Jenkins T, Fatheree
P, Kolesnikov A, Janc J W, Cregar L , Elrod K and Katz B, Bioorg. Med. Chem.
Lett,. 2006, 16, 710.
10. Mertens A, Müller-Beckmann B, Kampe W, Holck J P and Vonder Saal W, J.
a. Med. Chem. 1987, 30,1279.
11. Vinodkumar R, Vaidya S D, Siva Kumar B V, Bhise U N, Bhirud S B and Mashelkar
U C, Eur. J. Med. Chem., 2008, 43, 986.
12. Ramla M M, Omar M A Tokuda H and El.Diwani H I, Bioorg. Med. Chem., 2007, 15
,6489.
13. Trivedi P B, Undavia N K, Dave A ,M Bhatt K N and Desai N C, Indian. J. Chem.
Br., 1993, 32, 497..
14. Kant P, Indian. J. Heterocyc. Chem., 2006, 15, 221.
15. Srivastava M K, Mishra B and Nizamuddin, Indian. J. Chem. Br., 2001, 40,342.
16. Mishra P, Panneerselvam P and Jain S. J. Indian. Chem. Soc., 1995, 72, 559.
17. Jatav V, Jain S K, Kashaw S K and Mishra P, Indian. J. Pharm. Sci.,2006, 68, 360.
18. Alagarsamy V, Rajasolomon V, Vanikavitha G Paluchamy V, Ravi Chandran M,
Arnold Sujin A, Biol. Pharm. Bull.,. 2002, 25, 1432.
19. Pannerselvam P, Pradeepchandran R V, Sridhar S K, Indian. J. Pharm. Sci., 2003, 65,
268.
20. Rani P, Archana Srivastava V K and Kumar A, Indian. J. Chem. Br.,.2002, 41, 2642.
21. Archana,Srivastava V K, Chandra R, Kumar A, Indian. J. Chem. Br., 2002, 41, 2371.
22. Alagarsamy V, Thangathirupathi A, Mandal S C Rajasekaran S Vijayakumar S and
Revanthi R, Indian. J. Pharm. Sci.,2006, 68,108.
23. El-Hiti G A , Abdel-Megeed M F and Zied T, M. Indian. J. Chem. Br., 2002, 41,1519.
24. Murgan V, Thomas C C, Rama Sarma G V and Kumar E P , Indian. J. Pharm. Sci.,
2003, 65, 386.
25. Pattan S R, Krishna Reddy V V, Manvi F V, Desai B G, Bhat A R, Indian.
26. J.Chem. Br., 2006, 45, 1778.

Design, Synthesis, Antibacterial and Antifungal Activity 1489
27. Nandy P, Vishalakshi M T and Bhat A R, Indian. J. Heterocycl. Chem., 2006, 15,
293.
28. Lakhan R, Singh O P and Singh R L , J. Indian. Chem. Soc., 1987, 64, 316.
29. Bishnoi A, Saxena R, Srivastava K, Joshi M N and Bajpai S K, Indian. J.
30. Heterocycl. Chem., 2006, 15, 307.
31. Pandey V K and Mukesh Tandon M, Indian. J. Heterocycl. Chem., 2006, 15, 399.
32. National Committee for Clinical Laboratory Standards (NCCLS) standard methods for
Dilution antimicrobial susceptibility tests for bacteria, which grows
aerobically;Nat.Comm.Clini Lab stands,Ltd., Villanova., 1982, 242.
33. Margery Linday,E.Practical Introduction to Microbiology;E & F.N. Spon Ltd., 1962,
177.

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