We describe here the chemical modifications of nimesulide either via direct N-acylation or via a two-step process involving reduction of the nitro group followed by regioselective acylation/sulfonylation of the resulting arylamine. The acylation step of the second approach was found to be faster than acylation of nimesulide. A number of N-acylated and N-sulfonylated derivatives of N-(4-amino-2-phenoxy phenyl)methanesulfonamide obtained from nimesulide were conveniently prepared in good to excellent yields. Some of the compounds synthesized were tested for cyclooxygenase inhibition and few of them showed selectivity for COX-2.
nimesulide; reduction; acylation; sulfonylation; COX-1; COX-2
