Abstract:
Gastritis is a common virulent disease found in the present world. The main pathogen which can cause
gastritis is Helicobacter pylori and the infection from this bacterium in the upper gastrointestinal tract
can lead to ulcers and gastric carcinoma. The activity and the growth of this bacteria in gastric juice
of the stomach are favored by the bacterial urease enzyme. Therefore, urease enzyme inhibition plays
a significant role in reducing the survival of the pathogen in the stomach. Apart from that, due to
bacterial resistance and toxicity problems associated with the current drugs available against H. pylori,
discovery of novel urease inhibitors is highly demanded. In this study, two 3-hydroxyquinazolinone
derivatives were synthesized using anthranilic acid. Synthesized compounds were characterized
using NMR spectroscopy. Urease inhibitory action of the synthesized compounds was measured by a
colorimetric method called the Berthelot method. The amount of ammonia produced from urea due
to urease enzyme activity was determined by this method. Inhibition of urease resulted low levels of
ammonia produced and therefore low levels of absorbance. Among the two compounds, 3-hydroxy-
2-phenyl-4(3H)-quinazolinone exhibited high levels of inhibition at low concentrations with an IC50
value of 19.95 ± 1.03 μg/mL. This experiment was supported by a computational approach with the
use of Gold score software for docking analysis and Chimera 1.9 for visualization of the docked
molecules. The computational scores resulted in which 3-hydroxy-2-phenyl-4(3H)-quinazolinone
was shown to be a better urease inhibitor compared to 3-hydroxy-2-methyl-4(3H)-quinazolinone by
providing higher binding affinity and better Gold score values. Both experimental and computational
results favored 3-hydroxy-2-phenyl-4(3H)-quinazolinone as a preferable urease inhibitor.
