Title: Cysteamine
CAS Registry Number: 60-23-1
CAS Name: 2-Aminoethanethiol
Additional Names: mercaptamine; b-mercaptoethylamine; 2-aminoethyl mercaptan; thioethanolamine; decarboxycysteine; MEA; mercamine
Manufacturers' Codes: L-1573
Trademarks: Becaptan (Labaz); Lambratene (formerly) (Cilag Italiano)
Molecular Formula: C2H7NS
Molecular Weight: 77.15
Percent Composition: C 31.14%, H 9.15%, N 18.16%, S 41.56%
Line Formula: HSCH2CH2NH2
Literature References: A sulfhydryl compound with a variety of biological effects. Prepn: Gabriel, Leupold, Ber. 31, 2837 (1898); Knorr, Rössler, ibid. 36, 1281 (1903); Mills, Jr., Bogart, J. Am. Chem. Soc. 62, 1173 (1940); Wenker, ibid. 57, 2328 (1935); D. A. Shirley, Preparation of Organic Intermediates (Wiley, New York, 1951) p 189. Use in treatment of paracetamol (acetaminophen) poisoning: L. F. Prescott et al., Lancet 2, 109 (1976); A. L. Harris, Br. Med. J. 284, 825 (1982). Effects in nephropathic cystinosis: M. Yudkoff et al., N. Engl. J. Med. 304, 141 (1981). Radioprotective effects: R. P. Bird, Radiat. Res. 72, 290 (1980); C. J. Koch, R. L. Howell, ibid. 87, 265 (1981). Cysteamine has been shown to be a duodenal ulcerogen in rats: H. Selye, S. Szabo, Nature 244, 458 (1973); S. Szabo, Am. J. Pathol. 93, 273 (1978); P. Kirkegaard et al., Scand. J. Gastroenterol. 15, 621 (1980). Review: S. Szabo, Lab. Invest. 51, 121 (1984). It has also been found to deplete somatostatin concentration: S. Szabo, S. Reichlein, Endocrinology 109, 2255 (1981); S. M. Sagar et al., J. Neurosci. 2, 225 (1982). In pituitary tissue, cysteamine is a potent depletor of prolactin concentrations in vivo and in vitro: W. J. Millard et al., Science 217, 452 (1982). Toxicity studies: E. Beccari et al., Arzneim.-Forsch. 5, 421 (1955); D. L. Klayman et al., J. Med. Chem. 12, 510 (1969); P. K. Srivastava, L. Field, ibid. 18, 798 (1975).
Properties: Crystals by sublimation in vacuo. Disagreeable odor. mp 97-98.5°. Oxidizes to cystamine on standing in air. Freely sol in water, alkaline reaction. LD50 in mice (mg/kg): 625 orally; 250 i.p. (Klayman); (Srivastava, Field).
Melting point: mp 97-98.5°
Toxicity data: LD50 in mice (mg/kg): 625 orally; 250 i.p. (Klayman); (Srivastava, Field)
Derivative Type: Hydrochloride
Molecular Formula: C2H7NS.HCl
Molecular Weight: 113.61
Percent Composition: C 21.14%, H 7.10%, N 12.33%, S 28.22%, Cl 31.21%
Properties: Crystals from alc, mp 70.2-70.7°. Sol in water, alcohol. LD50 (cg/kg): 23.19 i.p. in rats; 14.95 i.v. in rabbits (Beccari).
Melting point: mp 70.2-70.7°
Toxicity data: LD50 (cg/kg): 23.19 i.p. in rats; 14.95 i.v. in rabbits (Beccari)
Use: Experimentally as a radioprotective agent and to produce acute and chronic duodenal ulcers in rats.
Therap-Cat: Antidote to acetaminophen.
Keywords: Antidote (Acetaminophen Poisoning).
Cysteic Acid Cysteine Cystine Cytarabine Cythioate

Skeletal formula
Ball-and-stick model
CAS number 60-23-1 YesY, 156-57-0 (HCl)
PubChem 6058
ChemSpider 5834 YesY
DrugBank DB00847
KEGG D03634 YesY
ChEBI CHEBI:17141 YesY
ATC code A16AA04,S01XA21
Jmol-3D images Image 1
Molecular formula C2H7NS
Molar mass 77.15 g mol−1
Melting point 95-97 °C
MSDS External MSDS
EU classification Harmful Xn
S-phrases S26 S36
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Cysteamine is the chemical compound with the formula HSCH2CH2NH2. It is the simplest stable aminothiol and a degradation product of the amino acid cysteine. It is often used as the hydrochloride salt, HSCH2CH2NH3Cl. The comparatively high melting point of cysteamine (95-97 °C), indicates that exists in a salt form.[1]