Abstract
An efficient synthesis of new pyrrolopyrimidinones 3a-d and isoxazolopyrimidinones 4a-c from the respective aminocyanopyrroles 1a-d and aminocyanoisoxazoles 2a-c is presented. The synthesized compounds were screened for antimicrobial activity against a panel of bacteria and fungi. Compound 4c exhibits remarkable activity against a broad spectrum of Gram-positive and Gram-negative bacteria and pathogenic fungi.