Facile One Pot Synthesis of Acridinediones Using Caffeine Hydrogen Sulfate Catalyst and Their Antimicrobial Evaluation.

A facile approach for the synthesis of bioactive acridinedione analogs using dimedone, aryl aldehydes, and ammonium acetate was developed using caffeine hydrogen sulfate catalyst in ethanol and water (2:1) solvent mixture at room temperature. The significant advantages of this procedure are efficient and simple method, ambient conditions, short reaction time (5–30 min), simple workup, easily recoverable catalyst, broad substrate scope and good yields (45–80%). Being water soluble, the catalyst was easily recovered by water and reused up to 4 runs. Moreover, the antimicrobial profile of synthesized derivatives was performed against different bacterial and fungal strains using broth microdilution method. Most of the synthesized derivatives exhibited significant activity against bacterial and fungal strains compared to standard. Compounds 4e (31.25 µg/mL and 31.25 µg/mL) and 4g (31.25 µg/mL and 62.5 µg/mL) were found the most active against E. coli. and S. aureus respectively with good MIC values. Compound 4f and 4j displayed the highest antifungal activity against A. niger with31.25 µg/mL MIC value. [ABSTRACT FROM AUTHOR]