Substituted quinazolinones and their anti-inflammatory activity.

6-Substituted-2-alkyl-3-(4-aminobenzene sulphonamido)quinazolin-4-(3H) ones (1a-b) were converted either to 2-methyl 3-[(N-aminoacylbenzoate)benzenes sulphonamido]quinazolin-4 (3H) ones (2a-c) or to 6-substituted-2-alkyl-3-(N-arylidene benzene sulphonamido)-quinazolin-4- (3H) ones (3a-h). 3 on reduction, yielded 6-substituted-2-alkyl-3-(N-arylmethyl sulphonamido)-quinazolin-4(3H)ones (4a-l). Reaction of 3a-h with thioglycolic acid afforded 2-alkyl-3-[4'-(5'-arylthiazolidin-3'-one)benzene sulphonamido]quinazolin-4(3H)ones (5a-h). All these compounds were evaluated for their anti-inflammatory activity against carrageenin induced rat's paw oedema. Active compounds were also evaluated for ulcerogenic liability and ALD50 values.