SYNTHESIS, CHARACTERIZATION AND ANTI-INFLAMMATORY ACTIVITY OF HYDRAZONES BEARING 5-NITRO-FURAN MOIETY AND 5-IODO-VANILLIN HYBRID

Abstract

The present paper describes the synthesis and anti-inflammatory activity of some new hydrazide-hydrazone derivatives (4a-n) from commercially available vanillin as starting material in three synthetic steps. Step 1 involves the iodination of vanillin in presence of benzyltrimethylammonium dichloroiodate as iodinating reagent; Step 2 involves the coupling of 2-(bromomethyl)-5-nitrofuran with 5iodovanillin in presence of room temperature ionic liquid such as [bmim] [PF6]; Step 3 involves condensation of 4-((5-nitrofuran-2-yl) methoxy)-3-iodo-5-methoxybenzaldehyde with various benzohydrazides under solvent free conditions resulting in the formation of final compounds, hydrazide-hydrazone derivatives. The structures of these derivatives were determined by 1 H NMR, IR, mass spectroscopic techniques and evaluated for anti-inflammatory activity (carrageenan induced inflammatory rat model). Compounds with substitution R = 4-F, 4-OH, 4-SO2Me, 2,4-difluoro and R = 3,4,5-trimethoxy in the main scaffold displayed significant anti-inflammatory activity.