Synthesis of biologically active angularly fused bisaroylbenzodifurans by PTC and solvent free microwave irradiation

Abstract

Angularly fused bisaroylbenzodifurans 3a-f have been synthesized by condensing 2,4-diacetyl resorcinol 1 with various p-substituted phenacyl bromides 2a-f under (a) phase transfer catalysis method and (b) microwave irradiation method. A comparison has been made between the two methods. Microwave irradiation has been found to be an efficient route for the synthesis of angularly fused bisaroylbenzodifurans. All the compounds 3a-f have been screened for anti-bacterial activity. The benzodifurans 3c and 3f have shown excellent activity against gram-positive (Staphylococcus aureus) bacteria at both 600 and 900 μg/mL and the compound 3b and 3d are found active at 900 μg/mL on the same bacteia. The bisaroylbenzodifurans 3a-f have also been screened for anti-fungal activity. The compounds 3c, 3d and 3f have shown maximum spore germination inhibition on Drechslera halodes fungi and the compounds 3a, 3b, 3c, 3d, and 3f have shown maximum spore germination inhibition on Fusarium oxysporum fungi at 960μg/mL. The bisaroylbenzodifurans 3a and 3e have been screened for anti-implantation activity as well and found to be inactive at 10 mg/kg/rat/day.