Benzoisothiazole is a benzo derivative of isothiazole, which is a kind of bicyclic aromatic organic compound, which is formed by fusion of a six-membered benzene ring and a five-membered heterocyclic ring composed of two adjacent heteroatoms, N and S. Benzoisothiazoles are important pharmaceutical intermediates. Some benzoisothiazole derivatives exhibit potent cytotoxic and antitumor activities.
Thiazolidine is a heterocyclic organic compound, which is a five-membered saturated ring with a thioether group and an amine group. It is the sulfur analog of oxazolidine. Thiazolidine derivatives have many uses and have a broad spectrum of biological activities. For example, the drug pioglitazone contains a thiazolidine ring. Thiazolidine has three isomers, 2-, 3-, and 4-. Derivatives with a 2-thiazoline ring are the most common.