THIOMALIC ACID FOR SYNTHESIS
A thiomalic acid or mercaptosuccinic acid is a dicarboxylic acid containing a thiol functional group. Mercaptosuccinic acid is used in the preparation of mercaptosuccinic acid diethyl ester by reaction with ethanol. It is also used as a brightening agent in metal plating.
It is also used as a brightening agent in metal plating. Further, it serves as an intermediate for the synthesis of corrosion inhibitors, soil fumigants, active pharmaceutical ingredients and electroplating agents.
Thiomalic acid is transformed into isocysteine using hexafluoroacetone as protecting and activating agent. The urethanes 5, 6, 7 obtained represent N-protected, carboxylic group activated derivatives of isocysteine and are perfectly suited for further derivatizations.