3-(4-Bromophenyl)-6-nitrobenzo [1.3. 2] dithiazolium ylide 1, 1-dioxide (5) was discovered as a new prototype for dual inhibitors of cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5- LOX). Thus, the structure–activity relationships of benzo [1.3. 2] dithiazolium ylide 1, 1- dioxide skeleton were carried out. The 6-NO2 group played an essential role in the inhibitory activity. In addition, moderate-sized lipophilic substituents at the para-position of the 3-aryl ...