Synthesis and anticonvulsant activity of some new 3-(p-sulfamoylphenyl)-4(3H)-quinazolinones.

In view of their expected anticonvulsant property, a series of 3-(p-sulfamoylphenyl)-4(3H)-quinazolinone derivatives (V) were synthesized by condensation of sulfanilamide with various 4H-3,1-benzoxazin-4-ones (III). Some 2-amido-N-(p-sulfamoylphenyl)benzamides (IV) were isolated as reaction intermediates. The structures of V were confirmed by IR, 1H-NMR, MS and elemental analyses. Some of the compounds V showed significant anticonvulsant effects against pentetrazol-induced convulsions.