Recyclable Keggin Heteropolyacids as an Environmentally Benign Catalyst for the Synthesis of New 2-Benzoylamino-N-phenyl-benzamide Derivatives under Microwave Irradiations at Solvent-Free Conditions and the Evaluation of Biological Activity.

2-Benzoylamino--phenyl-benzamide derivatives (-) were prepared from 2-phenyl-3,1-(4)-benzoxazin-4-one and substituted anilines - in the presence of a Keggin-type heteropolyacids series (H₃PWO·13H₂O; H₄SiWO·13H₂O; H₄SiMoO·13H₂O; and H₃PMoO·13H₂O) as catalysts without solvent and under microwave irradiation. We found that the use of H₃PWO·13H₂O acid coupled to microwave irradiation allowed obtaining a high-yielding reaction with a short time. The compound structures were established by ¹H-NMR and C-NMR. The antibacterial and antifungal activities of the synthesized compounds exhibited an inhibition of the growth of bacteria and fungi.