In order to discover new useful NSAIDs, novel N-substituted 1,2-benzisothiazoline-3-one 1,1- dioxide derivatives, which can exhibit potentially antiinflammatory activity were synthesized. 1,2-Benz-isothiazoline-3-one-N-acetic acids 6a, b were obtained from monochloroacetic acid and sodium 1,2-benz-isothiazoline-3-ones in DMF by N-alkylation reaction. N-Substituted 1,2-benzisothiazoline-3-one 1,1-dioxide derivatives 7a-e were synthesized through the coupling of compound 6a, b and several amines (aniline, 2- aminopyridine , 2-aminothiazole, 2-aminotetrazole) with dicyclohexylcarbodiimide in methyl e no chloride.