A Multicomponent Synthesis of 4H-Pyrido[1,2-a]pyrimidine-2-hydroxy-4-one Derivatives and Assessment of Their Antimicrobial Activity

A highly efficient method for the multicomponent synthesis of substituted 4H-pyrido[1,2-a]pyrimidine-2-hydroxy-4-one derivatives, starting from 4H-pyrido[1,2-a]primidine-2-hydroxy-4-one, β-naphthol, and substituted aromatic aldehydes, in moderate to good yields has been developed. The structure of the pyridopyrimidine derivatives was established by spectral methods. In vitro antibacterial activity of the newly synthesized compounds was evaluated against highly pathogenic Gram-positive [Staphylococcus aureus (MTCC 96)] and Gram-negative [Pseudomonas aeruginosa (MTCC 424), Salmonella typhi (MTCC 537), Klebsiella pneumoniae (MTCC 424), Escherichia coli (MTCC 64) and Chromobacterium violaceum] bacteria.