compounds of the following formula and their pharmaceutically acceptable salts ## spc1 ## wherein r 1 and r 4 are the same or different and are each a five or six membered n containing heterocycle attached at an available n atom ; r 2 is hydrogen , alkyl , trifluoromethyl , phenyl , benzyl , -- n -- r 4 or -- n -- n 2 ; r 3 is hydrogen , halogen , nitro , trifluoromethyl , alkyl , alkoxy , or alkylthio ; and n is an integer from 1 to 4 ; are disclosed . these compounds are useful as anti - inflammatory agents .