Synthesis, Characterisation and antimicrobial activity of Quinoline and Pyrazoline derivatives.

Abstract

The present investigation is in the interest of some synthesized novel derivatives 1-[3-(6-chloro-2-methyl-4-phenyl quinoline-3-yl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone 3(a-j) and 6-chloro-2-methyl-3-[5-1H-pyrazol-3-yl]-4- phenyl  quinoline 4 (a-j). The core nucleus quinoline scaffold is incorporated with  biological active heterocycle pyrazoline/pyrazole and benzene ring.. The characterization of the synthesised compounds reported is based on IR, 1H NMR, ¹³C NMR and mass spectral data. All the synthesised compounds were screened for their antibacterial activity on four bacteria (two Gram positive Species Bacillus subtilis, Staphylococcus aureus and two Gram negative species, Escherichia coli, Salmonella typhi) and antifungal activity on two fungi species (Aspergillusniger, Aspergillusfumigatus). Ciprofloxacin is used as bacterial standards and Amphotericin B is used as fungal standards for references to evaluate the efficacy of the tested compounds. Amongst the biological evaluated synthesised compounds 3d,4d and 5b exhibited most potent antimicrobial activity. It was observed that the presence of electron withdrawing group like chloro,fluoro and alkoxy at 6 position of quinoline and in the aromatic ring remarkably enhanced the antimicrobial activity.