Title: Thiourea
CAS Registry Number: 62-56-6
Synonyms: Thiocarbamide
Molecular Formula: CH4N2S
Molecular Weight: 76.12
Percent Composition: C 15.78%, H 5.30%, N 36.80%, S 42.12%
Line Formula: H2NCSNH2
Literature References: Made by fusing ammonium thiocyanate: Powers and Powers, Mitchell,
US 2552584;
US 2560596 (both 1951 to Koppers); by treating cyanamide with hydrogen sulfide: Robin, Jr.,
US 2173067 (1940 to Am. Cyanamid); Lewis,
US 2393917 (1946 to Monsanto); Van de Kamp,
US 2357149 (1944 to Merck & Co.). Toxicity data: Dieke
et al., J. Pharmacol. Exp. Ther. 90, 262 (1947).
Properties: Crystals, mp 176-178°. d 1.405. Soluble in 11 parts water, in alcohol; sparingly sol in ether. Neutral reaction. Forms addition compds with metallic salts. LD50 orally in wild Norway rats: 1830 mg/kg (Dieke).
Melting point: mp 176-178°
Density: d 1.405
Toxicity data: LD50 orally in wild Norway rats: 1830 mg/kg (Dieke)
CAUTION: Chronic administration in rats has resulted in hepatic tumors, bone marrow depression and goiters:
Clinical Toxicology of Commercial Products, R. E. Gosselin
et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) Section II, p 350. This substance is reasonably anticipated to be a human carcinogen:
Report on Carcinogens, Eleventh Edition (PB2005-104914, 2004) p III-250.
Use: In animal glue liquifiers and silver tarnish removers. Photographic fixing agent and to remove stains from negatives; manuf resins; vulcanization accelerator; a reagent for bismuth, selenite ions.
