Abstract

ANTIMICROBIAL ACTIVITIES; IONIC LIQUID AND MICROWAVEASSISTED SYNTHESIS OF RING-SUBSTITUTED 3-(3-BROMO-4- OXO-4H-CHROMEN-2-YL)-4H-CHROMEN-4-ONE

Ajay M. Ghatole*, Kushal R. Lanjewar, Mahesh K. Gaidhane

Abstract

An efficient procedure for the preparation of substituted 3-(3-(5- chloro-2-hydroxyphenyl)-3-oxoprop-1-enyl)-6-methyl-4H-chromen-4- one via the condensation of acetophenones with 6-sub-4-oxo-4Hchromene- 3-carbaldehyde in the presence of catalytic amount of ethylenediammonium diacetate (EDDA) using different ionic liquids at room temperature is described. The advantages of this method are generality, high yield, short reaction times, ease of product isolation, and ecologically friendly.A series of substituted 3-(3-bromo-4-oxo-4Hchromen- 2-yl)-4H-chromen-4-one were prepared by the reaction of 3- (3-(5-chloro-2-hydroxyphenyl)-3-oxoprop-1-enyl)-6-methyl-4Hchromen- 4-one in the presence of copper bromide and DMSO. A comparison of conventional heating and microwave irradiation in the synthesis of 3-(3- bromo-4-oxo-4H-chromen-2-yl)-4H-chromen-4-ones is discussed. Microwave irradiation was found to increase the yields of the desired products, shorten the reaction time. The newly synthesized compounds were characterized on the basis of elemental analysis, IR, 1H NMR and mass spectra. All the synthesized compounds were tested for their antibacterial activities against Gram +ve and Gram –ve bacteria, and antifungal activities.

Keywords: Chromone, acetophenone, aldehyde, ionic liquids, copper bromide, ethylenediammonium diacetate (EDDA), microwave .