1, 4-diazabicyclo [2.2.2] octane (DABCO) as an efficient organocatalyst were used for synthesis of annulated uracil derivatives via one-pot three component condensation reactions of substituted aromatic aldehydes, malononitrile and barbituric acid in aqueous ethanol carried at NTP. This is rapid, efficient synthetic route with several advantages viz; operational simplicity, mild reaction conditions, high yields of the biological active products, uses less toxic solvents and cheap catalyst. The synthesized products were screened for antimicrobial activity. Therefore annulated uracil derivatives   are excellent antimicrobial agents for globally alarming drug resistance issues in clinically used therapeutics.