Conventional and Microwave Assisted Synthesis of 3-(Substituted)-2-phenyl quinazolin-4(3H)-one and their Antibacterial and Anthelmintic Activity

Abstract

 The present research work was aimed to synthesize a series of various substituted quinazolinone containing 3-(substituted)-2-phenylquinazolin-4(3H)-one.  The compound 3-[(2-oxo-4-phenylazetidin-1-yl)-carbonyl]-2-phenylquinazolin-4(3H)-one, II was prepared by treating 4-oxo-2-phenyl-N-[(E)-phenylmethylidene]quinazoline-3(4H)-carboxamide, I with acetyl chloride and triethylamine (TEA) in benzene by conventional and microwave irradiation method. Synthesis of 3-[{2-oxo-3-(2,4-dichlorophenoxy)-4-phenylazetidin-carbonyl]-2-phenylquinazolin-4(3H)-one, III was carried out by reacting, I with 2,4-dichlorophenoxyacetic acid and thionyl chloride in benzene. The compound 2-phenyl-3-(5-phenyl-1H-1,2,4-triazol-3-yl)quinazolin-4(3H)-one, IV was obtained by reacting I with hydrazine hydrate in ethanol. Synthesis of 2-phenyl-3-(5-phenyl-1,2,4-oxadiazol-3-yl)-quinazolin-4(3H)-one, V was done by reacting I with hydroxylamine hydrochloride in ethanol. These derivatives were prepared by microwave as well as the conventional method. Structure of the compounds has been established by means of IR, 1H-NMR and MS. All the compounds were evaluated for antibacterial activity against Gram-positive bacteria like Staphylococcus aureus, Bacillus subtilis and Gram-negative bacteria like Pseudomonas aeroginosa, Escherichia coli. Most of the compounds showed significant antibacterial activities when compared with the standard drug ciprofloxacin at the concentration of 500 µg/ml and 250 µg/ml.  In this research work, in vitro anthelmintic activity of 3-(substituted)-2-phenylquinazolin-4(3H)-one carried out in comparison with piperazine citrate. These newly synthesized quinazolinone derivatives showed paralysis and were followed by death at concentrations of 10 mg/ml for the screening of the anthelmintic activity.