Abstract

SYNTHESIS AND BIOLOGICAL EVALUATION OF SOME NOVEL ISOXAZOLINE DERIVATIVES OF CARBOSTYRIL

Abhishek Kumar*, Jennifer Fernandes and Pankaj Kumar

ABSTRACT

A series of novel substituted 1-amino-3-(5-phenyl-4,5-dihydroisoxazol- 3-yl) quinolin-2(1H)-one (AJI1-AJI8) have been synthesized upon reaction with 1-amino-3-cinnamoyl-quinolin-2(1H)-one by using hydroxylamine hydrochloride as cyclising medium in alcohol medium. 1-amino-3-cinnamoyl-quinolin-2(1H)-one were synthesized by condensing 3-acetyl-1-amino-quinolin-2-one with different substituted benzaldehyde in presence of ethanolic KOH. The structures of the final synthesized compounds were confirmed by IR, 1H NMR and mass spectra. The synthesized compounds were screened for their antimicrobial, antioxidant and cytotoxicity activities. The synthesized compounds were screened for their antibacterial and antifungal activity against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, Aspergillus niger respectively by cup plate method. Compounds AJI2, AJI3, AJI5 and AJI8 showed good antibacterial activity compared to the standard drug ciprofloxacin. Compounds AJI2, AJI4, AJI5, AJI7 and AJI8 showed moderate antifungal activity compared to the standard drug fluconazole. The antioxidant activity of the synthesised test compounds was done using DPPH radical scavenging method. Compounds AJI1-AJI4 showed values at 22.85, 15.65, 13.41 and 95.62 respectively when compared to that of ascorbic acid at IC50 value of 3.69μg/ml and showed inhibitory concentration for 50% inhibition below 100 μg/ml. The final synthesized compounds were screened for their in vitro cytotoxicity activity against Ehrlich Ascites Carcinoma cells (EAC) by Trypan blue exclusion method. Compounds AJI1,AJI5, AJI7 and AJI8 induced the greatest effect on EAC cells with an activity more than 60% at a concentration of 250μg/ml.

Keywords: 2-Quinolones, isoxazoline, antibacterial activity, antifungal activity, antioxidant activity, cytotoxicity activity.