Synthesis and Anti-inflammatory Activity of Newer Indolyl Pyrazolines and Indolyl Isoxazolines

Abstract

Various 5-substituted aryl-3-(2′-carboxy-5′-methoxyindolyl)-2-pyrazolines (9-15) and 5-substituted aryl-3-(2′-carboxy-5′-methoxyindolyl)isoxazolines (16-22) have been synthesized by the cyclization of compounds 1-(2′-carboxyl-5′-methoxyindolyl-3-arylidenyl chalcones (2-8) by treating them with hydrazine hydrate/glacial acetic acid and hydroxylamine hydrochloride/2% NaOH, respectively and TLC checked for their purity. Structure of all these newly synthesized compounds was characterized by elemental (C, H, N) analysis and IR and 1H NMR spectroscopy. All the synthesized compounds were tested for their anti-inflammatory and ulcerogenic activities and acute toxicity and found to possess varying degrees of these activities. Compound 15 is 5-(3′′-methoxy-4′′-hydroxyphenyl)-3- (2′-carboxy-5′-methoxyindolyl)-2-pyrazoline found to be the most potent compound of the series, more potent than the standard drug phenylbutazone.