Synthesis, Characterization and Antimicrobial Activity
47
0.85 – 0.94 (4H, m, -CH ); anal. calcd. for C H N O
2
were found to have mild to good antibacterial activity against
all bacterial strains including B. subtilis, E.coli, H. influenza
and P. aeruginosa with 14.5 – 16 mm diameter of the inhibi-
tion zone. Both 2a and 2b did not show antifungal activity.
On the other hand, compound 3 showed highest activity
against all tested strains with 31.5 mm diameter of the zone
of inhibition against P. aeruginosa, followed by 30 mm
against H. influenza, and the least activity toward B. subtilis
with a 16 mm diameter of the zone of inhibition.
2
22 32
4
(384.52): C, 68.72; H, 8.39; N, 14.57; O, 8.32; found: C,
68.70; H, 7.89; N, 14.80; O, 8.50.
3.2. Antimicrobial Activity Testing
Antimicrobial activity was characterized using the fil-
ter-paper disc diffusion method. Discs were loaded with 3
different concentrations of test compounds, i.e., 1, 0.5, and
0.25 mg. The diameter of the zone of inhibition was recorded
in millimeters (mm) after 24 h incubation in case of bacteria
and 48 h for fungi.
ACKNOWLEDGMENTS
Antibacterial screening. The synthesized compounds
were evaluated for their antibacterial activity at a concentra-
tion of 1 mg/mL against selected bacterial strains cultured in
nutrient agar. Molten agar (100 mL) was poured into each
Petri plate and these plates were inoculated uniformly with
the cultures of tested microorganisms. Sterilized filter paper
disks coated with different compounds (1000 mg/disk) were
placed on the medium at suitable distances. Plates were kept
at 25°C for 1 h to allow good diffusion of compounds into
agar [21], and then plates were incubated for 24 h at 36 1°C
for bacteria. Then, the inhibition zones formed around the
compound-coated discs was measured in millimeters. Antibi-
otic ampicillin (at a concentration of 1mg/mL) was used as
standard drug to compare the results.
The authors would like to thank the Vice Chancellor of
the University of Sargodha and Prof. J. Kressler (Institute für
Chemie, Martin Luther University of Halle-Wittenberg,
Halle (Saale), Germany) for their moral and excellent techni-
cal support regarding this work.
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4. CONCLUSION
A new class of bioactive molecules of bis(phthalimi-
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to show high safety and efficacy. Compounds 2a and 2b
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