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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Synthesis and antibacterial activity of some new 2,3-dimethoxy-3-hydroxy-2-(1-phenyl-3-aryl-4-pyrazolyl)chromanones
Om Prakash1, Rajesh Kumar, Rakesh Sehrawat
1Department of Chemistry, Kurukshetra University, Kurukshetra 136 119, India. dromprakash50@rediffmail.com
Abstract:
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.
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