Synthesis, Characterization, Antimicrobial Screening of 5-Bromobenzofuranyl Aryl Ureas and Carbamates

Present work reports the biologically important benzofuran aryl ureas and carbamates. The benzofuran ring was formed by reacting bromo salicylaldehyde with diethyl bromomalonate in presence of dry acetone and anhydrous potassium carbonate to obtain 5-bromo-2-ethyl carboxylate (1). The obtained ester (1) was converted into corresponding hydrazide (2) by treating with hydrazine hydrate in ethanol. Compound 2 was then converted into 5-bromobenzofuran-2-carbonyl azide (3) by treating it with sodium nitrite in dioxane and acetic acid. The compound 3 is converted into 5-bromobenzofuranyl aryl ureas (4a-e) after treating primary amines and anhydrous toluene. 5-Bromobenzofuranyl aryl carbamate (5) and ethyl carbamate (6) were also synthesized by treating compound 3 with substituted phenol in toluene and ethanol respectively. All the compounds were characterized by NMR, IR and screened for antimicrobial activities.