thiourea

thi·o·u·re·a

T0169400 (thī′ō-yo͝o-rē′ə)n. A lustrous white crystalline compound, CH₄N₂S, the sulfur analog of urea, used as a developer in photography and photocopying and in various organic syntheses. Also called thiocarbamide.

thiourea

(ˌθaɪəʊˈjʊərɪə) n (Elements & Compounds) a white water-soluble crystalline substance with a bitter taste that forms addition compounds with metal ions and is used in photographic fixing, rubber vulcanization, and the manufacture of synthetic resins. Formula: H2NCSNH2

thi•o•u•re•a

(ˌθaɪ oʊ yʊˈri ə, -ˈyʊər i ə)

n. a colorless, solid substance, CH₄N₂S, used in photography and inorganic synthesis. [1890–95]

Thiourea

enUK

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

thiourea

thi·o·u·re·a

(thī'ō-yū-rē'ă), An antithyroid compound of the thioamide group, with the same actions and uses as thiouracil. Several derivatives of thiourea are useful in the treatment of leprosy. Synonym(s): thiocarbamide

thiourea

(thi?o-ur-e'a) [Gr. theion, sulfur, + ouron, urine] H₂NCSNH₂; A colorless crystalline compound of urea in which sulfur replaces the oxygen. Synonym: sulfourea

单词	thiourea
释义	thiourea enUK thi·o·u·re·a T0169400 (thī′ō-yo͝o-rē′ə)n. A lustrous white crystalline compound, CH₄N₂S, the sulfur analog of urea, used as a developer in photography and photocopying and in various organic syntheses. Also called thiocarbamide. thiourea (ˌθaɪəʊˈjʊərɪə) n (Elements & Compounds) a white water-soluble crystalline substance with a bitter taste that forms addition compounds with metal ions and is used in photographic fixing, rubber vulcanization, and the manufacture of synthetic resins. Formula: H2NCSNH2 thi•o•u•re•a (ˌθaɪ oʊ yʊˈri ə, -ˈyʊər i ə) n. a colorless, solid substance, CH₄N₂S, used in photography and inorganic synthesis. [1890–95] Thiourea enUK 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 thiourea enUK thi·o·u·re·a (thī'ō-yū-rē'ă), An antithyroid compound of the thioamide group, with the same actions and uses as thiouracil. Several derivatives of thiourea are useful in the treatment of leprosy. Synonym(s): thiocarbamide thiourea (thi?o-ur-e'a) [Gr. theion, sulfur, + ouron, urine] H₂NCSNH₂; A colorless crystalline compound of urea in which sulfur replaces the oxygen. Synonym: sulfourea
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