HSCH2CO2H

HSCH2CO2H, also known as thioglycolic acid or mercaptoacetic acid, is an organosulfur compound with the chemical formula HSCH2CO2H. It is a colorless liquid with a characteristic strong odor. This compound is structurally similar to acetic acid, with a thiol group (-SH) replacing one of the hydrogen atoms on the methyl group.

Thioglycolic acid is readily soluble in water and common organic solvents. Its chemical properties are largely dictated by the presence of both the thiol group and the carboxylic acid group. The thiol group can undergo oxidation and readily forms disulfide bonds. The carboxylic acid group exhibits typical acidic behavior.

It finds widespread application in various industries. In cosmetics, it is a key ingredient in hair perming and depilatory products due to its ability to break disulfide bonds in keratin. In industrial settings, it is used as a chelating agent, a reducing agent, and in the synthesis of various chemicals. It also plays a role in photography as a developing agent and in the leather industry for dehairing hides. Thioglycolic acid is considered a moderately toxic substance and requires careful handling.