Synthesis and antibacterial activity of some new 2,3-dimethoxy-3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromanones.

Seven new 2,3-dimethoxy-3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromanones (5) have been synthesized by the oxidation of 3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromones (4) with iodobenzene diacetate in methanol. The structures of compounds 5 were established by the combined use of (1)H NMR, IR and mass spectra. All the seven compounds (5) were tested in vitro for their antibacterial activity against gram-positive bacteria namely, Staphylococcus aureus, Staphylococcus epidermidis and Bacillus pumilus and two gram-negative bacteria namely, Salmonella typhi and Pseudomonas aeruginosa. Three compounds, 5d, 5f and 5g, have displayed antibacterial activity comparable to the commercial antibiotics, Linezolid, Cefaclor and Cefuroxime axetial.