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.
Amino acids are organic compounds containing a basic amino group and an acidic carboxyl group. Because amino acids contain both amino and carboxyl groups, they can be polymerized in an end-to-end manner, removing a molecule of water to form a covalent amide bond or peptide bond. Many amino acids are linked together end to end to form a polypeptide. Amino acids and peptides are important components in the fields of medicine and life sciences.