الفهرس 
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Abstract
The present study is concerned with the design and synthesis of novel thiazolidinedione derivatives bearing a quinoline moiety and the biological evaluation of their antibacterial activities. The thesis consists of four main sections: introduction, the aim of work, results & discussion, and the experimental section in addition to references and summary.
1-Introduction
The introduction part presents a literature survey about thiazolidinediones as potential anticancer and antibacterial entities, thiazolidinones and quinolines as potential antibacterial entities. In addition, this part involves the synthesis, mechanism of action, chemistry, and spectral properties of thiazolidinedione moiety.
2-Aim of the work
This section outlines the goals and objectives for the design of this research including synthesis of the target compounds, biological evaluation of the antibacterial activity of the prepared compounds, and studies of the mechanism of antibacterial activity induced by some of the synthesized compounds.
3-Results and discussion
This section is subdivided into three main sections:
A-Chemistry section
Chemistry section, which includes description of different methods used for synthesis of the intermediates and their corresponding, targeted compounds. Also, it displayed structural elucidations of these compounds by different spectroscopic techniques including 1H-NMR, 3C-NMR, LC-MS/MS and elemental analysis.
In this work we reported the synthesis of the following compounds:
• Twenty-eight reported compounds: 1a-g, 2a-g, 3a-f, 4, 5a-c, 6a, 6b,7, 8.
• One new intermediate: 3g.
• Novel Twenty-one compounds: 5d, 5e, 6c-f, 9a-g, 10a-c and 11a-e.
B-Biology section:
This section is subdivided into two main sections:
i. Evaluation of urease inhibitory activity
The results revealed that among the tested compounds, compounds 9a, 9d, 11b, and 11d showed promising urease inhibitory activity and they were the most potent urease inhibitors with IC50 values equal to 16.54, 28.88, 26.38, and 18.47 µM, respectively, in comparison with ciprofloxacin and thiourea with IC50 of 27.97 and 22.18 µM, respectively. While compounds 9c, 9g, 11a, and 11c displayed moderate activity with IC50 values equal to 61.22, 45.53, 55.63, and 34.88 µM, respectively. Moreover, 9e, 9f, and 11e, revealed weak urease inhibitory activity with IC50 values equal to 80.13, 69.70 and 90.01µM, respectively. Finally, compound 9b showed very weak urease inhibitory activity with IC50 values equal to 156.00 µM, respectively, in comparison with the reference drug ciprofloxacin.
ii. Evaluation of antibacterial activity
The most potent compounds 9a, 9d, 11b, and 11d were selected for antibacterial screening using the standard agar diffusion method using four Gram-positive bacterial strains E. durans, S. aureus, S. epidermidis, and S. Pneumoniae, in addition to two Gram-negative urease producing bacterial strains, Proteus mirabilis and Klebsiella pneumonia using ciprofloxacin as positive controls.
C-Molecular Docking section
The Discovery studio program was utilized to study the docking of the test compounds on the active site of the urease enzyme. The docking reliability was validated using the known X-ray structure of Helicobacter pylori urease (PDB: 1E9Y) in a complex with acetohydroxamic acid (AHA).
4-Experimental
This section outlines the detailed procedures of different experiments used. It includes three parts:
i. Chemistry section
Chemistry section this section described the different procedures used for the synthesis of the target compounds 5a-e, 6a-f, 9a-g, 10a-c, and 11a-e. This section also presented all detailed spectroscopic and analytical data of the synthesized compounds.
ii. Biology section
Biology section, this part outlined the procedures used to investigate the antibacterial activity of the synthesized compounds by two methods, evaluation of urease inhibitory activity and screening of antibacterial activity.
iii. Molecular docking
Molecular docking, this section describes the methodology and software used for the molecular modeling of the selected compounds to investigate their binding mode with the Helicobacter pylori urease (PDB: 1E9Y) in complex with acetohydroxamic acid(AHA) using the Discovery Studio software package.