Microwave-assisted synthesis and biological evaluation of some coumarin hydrazides

Abstract

In this work, 15 different coumarin hydrazides were successfully synthesized and screened for their antioxidant and antilipase activities. To do this, firstly, salicylaldehyde derivatives and Meldrum's Acid were reacted in absolute ethanol with catalytic amount of pyridine to obtain coumarin-3-carboxylic acid derivatives (1a-e). Then, these compounds were treated with 1H-benzotriazole in dichloromethane by using thionyl chloride to synthesize benzotriazole derivatives (2a-e). Then, compounds 2a-e were reacted with three commercial hydrazides (nicotinic hydrazide, benzhydrazide,and phenyl acetichydrazide) in ethanol by using microwave irradiation and conventional heating procedures to obtain final products (3-5a-e). Finally, these compounds were tested for their anti-oxidant and anti-lipase activities. The structure of newly synthesized compounds was identified by IR, 1H NMR, 13C NMR, and elemental analysis data.