An efficient microwave assisted synthesis of substituted quinoxalines in presence of MgBr2.OEt2 catalyst. Recycling of the catalyst has been efficiently achieved using a simple procedure. All the compounds are characterized by 1H NMR and Mass spectral studies. All the synthesized compounds were screened for four different bacterial strains (Escherichia coli and Proteus mirabilis are gram (-) ve strains, Staphylococcus aureus and Bacillus subtilis are gram (+) ve strains).