Diethyl bromomalonate (2) with an equimolar amount of 2-aminophenol (1) in the presence of sodium fluoride undergoes a cyclization reaction to form 2H,4H-2-ethoxycarbonyl-3,4-dihydro-3-oxo-1,4-benzoxazine (3). Furthermore, compound 3 undergoes a condensation reaction with hydrazine hydrate in the presence of methanol to yield 2H,4H-2-hydrazinocarbonyl-3,4-dihydro-3-oxo-1,4-benzoxazine (4), whic...

A series of E-4-(3-oxo-3-(substituted)prop-1-en-1-yl)benzoic acid derivatives (1-5) were synthesized by the Claisen-Schmidt condensation various ketones with 4-formylbenzoic acid. The anticholinesterase (AChE and BChE), tyrosinase, urease inhibition activities compounds examined. It was found that most active compound against AChE enzyme in activity 1. Compound 4 tyrosinase activity, while 3 ps...