M. Bahnous et al. / Bioorg. Med. Chem. Lett. 23 (2013) 1274–1278
1277
Table 2
Crystal data for characterized compounds
Compounds
9a
9b
9c
9d
9f
Crystal system
Space group
a (Å)
b (Å)
c (Å)
Orthorhombic
Pcab
7.1740(2)
11.9743(3)
35.0273(8)
90
Monoclinic
P21/c
5.4562(2)
18.0551(6)
16.4893(6)
90
Monoclinic
C2/c
31.8115(18)
7.9772(5)
14.3825(9)
90
Monoclinic
P21/a
10.8527(4)
9.6643(3)
16.4305(6)
90
Orthorhombic
P212121
6.0194(8)
11.8657(15)
19.396(2)
90
a
(°)
b (°)
90
90
91.8320(10)
90
1623.57(10)
4
101.934(3)
90
3570.9(4)
8
106.3150(10)
90
1653.90(10)
4
90
90
1385.3(3)
4
c
(°)
V (Å3)
3008.97(13)
8
Z
Table 3
In conclusion, as demonstrated herein, the approaches devel-
oped in this work allow an efficient access to new haloimidazolium
and nitroimidazolium salts using appropriate synthetic routes.
These approaches allow a diverse range of compounds to be pre-
pared in good yields. All the target compounds were evaluated
for their in vitro antimicrobial activity against Escherichia coli,
Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella
typhimurium. In most cases, prepared ionic derivatives have shown
moderate to significant antibacterial activities against especially
Gram negative bacteria pathogens selected in this study and, iodin-
ated compounds are the most promising antibacterial agents, and
can serve as potential leads for further drug discovery study.
In vitro antibacterial activity of compounds 9a–g and 10a–e
MIC (lg/mL) (zones of inhibition in mm)
Products
Ec
Sa
Pa
St
9a
9b
9c
9d
9e
9f
9g
10a
25(7)
12.5(9)
50(9)
>250(7)
>250(7)
250(12)
>250(15)
250(15)
>250(NI)
>250(9)
>250(NI)
>250(10)
>250(9)
>250(NI)
250(NI)
22
50(9)
150(9)
50(8)
12.5(9)
25(8)
12.5(9)
>250(10)
25(7)
250(NI)
25(7)
25(9)
6.2(9)
0
>250(NI)
>250(7)
150(7)
25(8)
12.5(9)
12.5(NI)
50(7)
>250(NI)
>250(NI)
25(7)
>250(NI)
50(NI)
9
12.5(9)
25(12)
12.5(NI)
50(9)
150(7)
25(NI)
50 (NI)
25(NI)
6.2(NI)
9
10b
10c
10d
Acknowledgments
10e
Spiramicyn*
We thank MESRS (Ministère de l’Enseignement Supérieur et de
la Recherche Scientifique) and ANDRU (Agence Nationale pour le
Développement de la Recherche Universitaire) Algeria, for financial
support.
NI: No inhibition zone.
Disc charge 100 lg.
*
suggested that compounds possessing 1-oxo-1-phenyleth-2-yl
linked to N2 (9a–g) have more antimicrobial activity compared
to the corresponding ethyl ester derivatives 10a–e (Table 3).
In series of brominated compounds 9a–c, the best results were
observed with 2-phenylimidazole quaternized with 1-oxo-1-
phenyleth-2-yl) entity (compounds 9c) which have shown a signif-
icant inhibition effect on the growth of Gram positive bacteria like
Staphylococcus aureus.
Supplementary data
Supplementary data associated (analytical data for synthetic
products) with this article can be found, in the online version, at
References and notes
The comparison of inhibition zone diameters in 4,5-dihalogeno-
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(MIC 66.2
lg/mL). Furthermore, the non substitued imidazolium
9f presents better inhibition compared to its methylated analog 9g.