Abstrait

Design and synthesis of some new pyrazole derivatives as anti-inflammatory and antimicrobial agents

Sabir Hussain, Deepika Kaushik

2-(6,8-Dibromo-2-methylquinazolin-4-yloxy)-acetohydrazide (4) was prepared by the reaction of 6,8-dibromo-2-methylbenzo-[d][1,3]oxazin-4-one with formamide to afford quinazolinone (2), followed by alkylation with ethyl chloroacetate to give the ester (3). Treatment of ester (3) with hydrazine hydrate and benzaldehyde afforded (4) and styryl quinazoline (5). The hydrazide was reacted with triethyl orthoformate, acetylacetone and ethyl acetoacetate and benzaldehyde derivatives to afford the corresponding pyrazoles (6), (7), (9) and hydrazone derivatives (10a-c). Cyclization of hydrazone (10a-c) with thioglycolic acid afforded the thiazole derivatives (11a-c). The newly synthesized compounds were characterized by their spectral (IR, 1H, 13C NMR), Selected derivatives of these compounds were screened for anti-inflammatory and antimicrobial agents.