N-Substituted 2-sulfenamoylbenzoates and 1,2-benzisothiazolin-3-ones were effectively synthesized by the substitution reaction between S-[2-(3-oxo-1,2-benzisothiazolinyl)]-2-mercaptobenzoates (2) and primary amines. The substitution reaction occurred on the sulfur atom of the 2-sulfenamoyl group of 2, and 1,2-benzisothiazolin-3-one behaved as a leaving group. The eliminated 1,2-benzisothiazolin-3-one