Thiourea


Also found in: Dictionary, Medical, Wikipedia.

thiourea

[¦thī·ō·yu̇′rē·ə]
(organic chemistry)
(NH2)2CS Bitter-tasting, white crystals with a melting point of 180-182°C; soluble in cold water and alcohol; used in photography and photocopying, as a rubber accelerator, and as an antithyroid drug in treating hyperthyroidism. Also known as thiocarbamide.

Thiourea

 

(or thiocarbamide), H2NC(S)NH2, a white crystalline substance with a bitter taste. Melting point, 180°–182°C upon rapid heating (decomposes upon slow heating). Moderately soluble in water, methanol, and pyridine, and freely soluble in 50 percent aqueous pyridine.

Thiourea is obtained by isomerization of ammonium thiocyanate (a) and by the addition of hydrogen sulfide to cyanamide (b):

Hydrolysis of thiourea yields ammonia, hydrogen sulfide, and carbon dioxide. Alkylation of thiourea produces the S-alkyl derivatives of isothiourea, S-alkylisothiouric salts (I), which decompose under the action of alkalies to form mercaptans (II):

where X is a halogen and R is an alkyl.

Thiourea is used in the synthesis of various organic compounds, including pharmaceuticals, and as a growth substance. Thiourea yields inclusion compounds with branched and cyclic alkanes, but not with hydrocarbons of normal structure. This property is used for the separation of these two groups of compounds.

B. L. DIATKIN

References in periodicals archive ?
Conclusion: Application of thiourea at rate of 300 mg/L resulted in significant increase in growth, yield and yield related attributes of late sown wheat crop.
Increasing concentrations of acetate, thiourea, and urea dissolved in acetic acid with number of cycles could have rendered it less effective as a precipitating agent.
In the Advance Publication of "Aerial Application of Mancozeb and Urinary Ethylene Thiourea (ETU) Concentrations among Pregnant Women in Costa Rica: The Infants' Environmental Health Study (ISA)" by van Wendel de Joode et al.
Trapping potential of thiourea in presence and absence of EDTA-[EC.sub.50] 42.76 [+ or -] 2.09 and 77.28 [+ or -] 1.16, respectively.
Synthesis, characterization and antimicrobial studies of mixed ligand silver(I) complexes of thioureas and triphenylphosphine.
Foliar applied thiourea improved ECe (6-11%) and high temperature tolerance (4-10%) in these varieties at different stages.
According to new report available with Million Insights, Thiourea is an organosulfur compound also termed as thiocarbamide that resembles urea but contains sulfur instead of oxygen.
It was found that thiocyanate was an environment friendly reagent for gold leaching and more stable than thiourea in acidic solution.
Samples Total phenolics (mgGAE/mg extract) (n=3) Ultrasonic bath Maceration Methanol 0.0084[+ or -]0.0003 0.0097[+ or -]0.0002 p=0.005 (*) Thiourea Samples Urease inhibition (%) (25 [micro]g/mL) (n=2) Ultrasonic bath Maceration Methanol 31.012[+ or -]2.6 (b) 27.125[+ or -]1.9 (b) Thiourea 96.85[+ or -]0.9 GAE-Gallic acid equivalents (b) Significancy of T.
Anion Complexation Studies of 3-Nitrophenyl-Substituted Tripodal Thiourea Receptor: A Naked-Eye Detection of Sulfate via Fluoride Displacement Assay.
Leaching and CIL processes in gold recovery from refractory ore with thiourea solutions.