الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Nalidixic acid; 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthy-ridine-3-carboxylic acid 121a, is a synthetic 4-quinolone analog antimicrobial agent, while norfloxacin; 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(piperazin-1-yl)quinoline-3-carboxylic acid 122a, is considered a synthetic second generation 4-quinolone antibacterial agent. Both drugs suffer from some adverse reactions. They induce gastrointestinal disturbances which could be attributed to their strongly acidic character. Neurological side effects including visual disturbances, headache, dizziness and vertigo have been also reported. Other side effects include crystallurea encountered with large doses, which could be related to their poor aqueous solubility. Nalidixic acid provokes photosensitivity reactions, while norfloxacin shows a limited bioavailability, since only 35-40% of the dose is absorbed, which could be attributed to its zwitter-ionic character. literature survey revealed that prodrug concept has been approached in order to improve their physicochemical and biological properties. However, there is much remaining to be done in this concern. The afore-mentioned facts motivated us to sysnthesize new bioreversible derivatives of nalidixic acid and norfloxacin. In this direction, the prodrug strategy involving the 3-carboxylic group has been proposed to synthesize some selected glycolamide esters as well as glycerides. Esterification of nalidixic acid and norfloxacin with metronidazole and secnidazole to obtain mutual bipartate ester prodrugs was also within the scope of our interest. These mutual prodrugs would be reverted in vivo delivering the two active parent drug molecules, thereby broadening the antibacterial spectra of both counterparts.