Mercaptoacetic acid

Thioglycolic acid

Names
Preferred IUPAC name Sulfanylacetic acid
Other names 2-Sulfanylacetic acid 2-Mercaptoacetic acid Acetyl mercaptan Mercaptoacetate Mercaptoacetic acid Thioglycolic acid Thiovanic acid
Identifiers
CAS Number	68-11-1 Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:30065 Y
ChemSpider	1101 Y
ECHA InfoCard	100.000.616
KEGG	C02086 Y
PubChem CID	1133
UNII	7857H94KHM Y
InChI InChI=1S/C2H4O2S/c3-2(4)1-5/h5H,1H2,(H,3,4) Y Key: CWERGRDVMFNCDR-UHFFFAOYSA-N Y InChI=1/C2H4O2S/c3-2(4)1-5/h5H,1H2,(H,3,4) Key: CWERGRDVMFNCDR-UHFFFAOYAP
SMILES C(C(=O)O)S
Properties
Chemical formula	C2H4O2S
Molar mass	92.11 g·mol−1
Appearance	colorless, clear liquid
Odor	strong, disagreeable
Density	1.32 g/cm3
Melting point	−16 °C (3 °F; 257 K)
Boiling point	96 °C (205 °F; 369 K) at 5 mmHg
Solubility in water	miscible
Vapor pressure	10 mmHg (17.8°C)
Magnetic susceptibility (χ)	-50.0·10−6 cm3/mol
Hazards
Flash point	> 110 °C; 230 °F; 383 K
Explosive limits	5.9%-?
US health exposure limits (NIOSH):
PEL (Permissible)	none
REL (Recommended)	TWA 1 ppm (4 mg/m3) [skin]
IDLH (Immediate danger)	N.D.
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Thioglycolic acid (TGA) is the organic compound HSCH₂CO₂H. TGA is often called mercaptoacetic acid (MAA). It contains both a thiol (mercaptan) and carboxylic acid functional groups. It is a colorless liquid with a strongly unpleasant odor. TGA is miscible with polar organic solvents.

TGA is used as a chemical depilatory and is still used as such, especially in salt forms, including calcium thioglycolate and sodium thioglycolate. TGA is the precursor to ammonium thioglycolate that is used for permanents. TGA and its derivatives break the disulfide bonds in the cortex of hair. One reforms these broken bonds in giving hair a "perm." Alternatively and more commonly, the process leads to depilation as is done commonly in leather processing. It is also used as an acidity indicator, manufacturing of thioglycolates, and in bacteriology for preparation of thioglycolate media. In fact thioglycolysis reactions used on condensed tannins to study their structure.

Organotin derivatives of thioglycolic acid isooctyl esters are widely used as stabilzers for PVC. These species have the formula R₂Sn(SCH₂CO₂C₈H₁₇)₂.

Applying TGA can soften nails and then fix pincer nails in the correct position.

Sodium thioglycolate is a component of a special bacterial growth media : thioglycolate broth. It is also used in so-called "fallout remover" or "wheel cleaner" to remove iron oxide residue from rims.Ferrous ion combines with thioglycolate to form red-violet ferric thioglycolate.