Synthesis, biological studies of some new trifluoromethyl and halogen substituted quinoline derivatives

Abstract

The heterocyclic chemistry is one of the most important and complex branches of organic chemistry, which provides variety of biologically important compounds. The most recent innovative improvements and developments in health technologies, includes success in the discovery and production of new drugs. In recent years, the mounting threat of bacterial resistance has heightened the urgency to discover and develop anti-ineffective agents with novel mechanism of action and enhanced activity profile. Quinoline nucleus is an important class of heterocyclic compounds found in many synthetic and natural products with a wide range of pharmacological activities. Quinolone derivatives have significant tissue penetration property and inhibit the DNA synthesis by forming complex with DNA gyrase or topoisomerase II enzyme. Prompted by the biological significance of quinoline and with the aim of finding new trifluoromethylquinoline derivatives having enhanced antimicrobial activity, in the present research work it was planned to synthesize some new quinoline derivatives. Based on the literature survey five series of quinoline derivatives were planned and synthesized. The synthetic and purification methods have been optimized for the new derivatives. Characterizations of newly synthesized compounds were successfully done by means of spectral methods like IR, 1H-NMR, 13C-NMR, mass spectral and elemental analysis. Three dimensional structures of some derivatives were evidenced by X-ray crystallographic study. All the newly synthesized compounds were tested for their invitro antimicrobial activity. Some of the synthesized compounds were found to exhibit potent activity. A combination of trifluoromethylquinoline with certain substituents has caused an enhanced antimicrobial activity. Hence they are ideally suited for further modifications to obtain more efficient antimicrobial agents.