Microwave-assisted three-component synthesis and in vitro antifungal evaluation of 6-cyano-5,8-dihydropyrido[2,3-d]pyrimidin-4(3H)-ones

The reaction of 6-aminopyrimidin-4-ones 1 with benzaldehydes 2 and beta-aminocrotononitrile 3 or benzoylacetonitrile 4 under microwave irradiation in dry media yields the 6-eyano-5,8-dihydropyrido[2,3-d]pyrimidinones 5a-t. The structure of the synthesized compounds was determined on the basis of nmr measurements, especially by H-1, H-1-, H-1, C-13 COSY, DEPT and NOESY experiments. In contrast with other pyrido[2,3-d]pyrimidine derivatives, these compounds did not show any antifungal in vitro activity up to 250 mu g/mL.