Synthesis of thiazolyl quinazolones for studying their antiviral activity against Japanese encephalitis virus (JEV), a RNA virus of high pathogenicity

The synthesis of 2-Phenyl-3,1-benzoxazine-4-one 1 have been obtained from Antharanilic acid bystirring in dry pyridine at room temperature. The compound 1 are then converted to their respectivequinazolone 2 by treatment with hydrazine hydrate and Compound 3 by treatment with 1,1-biphenyl-4,4-diamine. The compound 4&5 on heating with aromatic aldehyde to give 3-(p-Arylidenoamino diphenyl)/2-Phenyl-3-arylidene-amino-4-(3H) quinazolone. Interaction of compound 4&5 with thioglycollic acidundergoes cyclization to give3-(p-Arylidenoamino diphenyl)/2-Phenyl-3-{3'-(2-aryl-4-oxo-1',3'-l)]quinazolones. The in vitro anti-JEV activity of these compounds has also been evaluated.