Ammonium derivatives of chromenones and quinolinones as lead antimicrobial agents

A series of novel ammonium derivatives were synthesized and examined for their antimicrobial efficacy. Comparison of antimicrobial spectrum revealed that compounds 9, 11, 16 and 23 had strong potential against pathogens in vitro. Cytotoxicity results showed compound 9 to be least toxic, it is non-toxic to A549 and U87 cells in MTT assay and exhibits marginal toxicity (15–20%) to human erythrocytes at a concentration of 1000 μg/ml as compared to 100% lysis of cells by 31.25 μg/ml of the standard drug amphotericin B. This compound has MIC values in the range of 1.95–31.25 μg/disc in DDA against different pathogens and may considered to be an important lead antimicrobial molecule for further exploration.