Thio-

also before a vowel thi-, repr. Gr. θεῖον sulphur; a formative element in names of things containing or connected with sulphur.

  1.  in Chem. (See also THIOL-, THION-.) In names of compounds containing sulphur = sulpho-.

  In systematic nomenclature restricted to those in which one or more atoms of sulphur take the place of one or more of oxygen in the substance designated by the rest of the name; e.g. thiacetic acid C₂H₃O.SH, from acetic acid C₂H₃O.OH, tri-thiocarbonic acid H₂CS₃, from carbonic acid H₂CO₃. So thio-acid, -alcohol, -aldehyde, -ether, -salt; also thioantimonic, -antimonious, -arsenic, -arsenious, -lactic, -phosphoric, -phosphoryl, -stannic, tungstic, etc. But many names do not conform exactly to this systematic use.

  The following are the chief combinations of thio-.

  Thiacetate, a salt of thiacetic acid. Thiacetic a., in thiacetic acid (C₂H₃O . SH), a colorless liquid boiling at 93°C. Thi-acid = thio-acid. Thialdine [ALD(EHYDE + -INE⁵], a crystalline substance, NH:2(CHCH₃.S):CHCH₃, produced by passing hydrogen sulphide into a solution of aldehyde ammonia. Thialol [AL(COHOL + -OL 3], a name for diethyl disulphide, (C₂H₅)₂S₂, a colorless oily compound, having an odor like garlic. Thiamide, generic name for substances formed by replacing the oxygen of an amide by sulphur, as thiacetamide, CH₃CS.NH₂, from acetamide, CH₃CO.NH₂. Thiamine, generic name for amines containing the group NHSH, as ethylthiamine, C₂H₅.NHSH. Thiazole [AZO- + -ole, -OL 3], N〈^CH.S/_CH:CH, a liquid boiling at 117°C. Thienyl [contr. of thiophenyl, proposed 1883 by V. Meyer], the radical C₄H₃S contained in thiophene, C₄H₄S. Thio-acid, thi-acid, an acid in which oxygen is replaced by sulphur. Thio-albumose, a deutero-albumose containing a large amount of sulphur. Thio-alcohol, a compound of the nature of an alcohol in which sulphur takes the place of oxygen, as mercaptan, C₂H₅.SH, analogous to ethyl alcohol, C₂H₅.OH. Thiocarbamate, a salt of thiocarbamic acid. Thiocarbamic a., in t. acid, NH₂.CO.SH and NH₂.CS.OH: now distinguished as thiolcarbamic and thioncarbamic acids: see THIOL-, THION-. Thiocarbamide, CS(NH₂)₂, or HS.C(NH₂):NH, a crystalline substance melting at 170°C. Thiocarbonate, a salt of thiocarbonic acid. Thiocarbonic a., in t. acid: in derivatives, as mono-, di-, tri-thiocarbonic acid: the last, H₂CS₃, is a dark yellow strongly smelling oil, very easily decomposed by heating into CS₂ and H₂S; esters of dithiocarbonic acid, H₂COS₂, and of monothiocarbonic acid, H₂CO₂S, are known. Thiocarbonyl, the radical (CS)″, in which the oxygen of carbonyl (CO)″ is replaced by sulphur. Thiocarbylamine = iso-thiocyanic acid, CHNS, = C=N.SH. Thiocresol, a compound with the formula CH₃:C₆H₄SH, of which there are three modifications, two crystalline and one liquid. Thiocyanate, a salt of thiocyanic acid. Thiocyanic a., in t. acid, N:C.SH = cyanic acid, N:C.OH, in which oxygen is replaced by sulphur; a liquid with a penetrating odor. Thiocyanogen, the radical CNS of thiocyanic acid; in comb. thiocyano-. Thioformic a., in t. acid, H₂COS, a crystalline substance melting at 120°C. Thionaphthene, a colorless crystalline compound, C₈H₆S, consisting of benzene, C₆H₆, of which two atoms of H are replaced by CH:CH.S. Thionic a., in t. acids, group name for the acids represented by the formula H₂S_nO₆, where n = 2, 3, 4, 5, and perhaps 6. These acids are called dithionic, trithionic, tetrathionic, pentathionic, and hexathionic acid. Thionine, a brownish-black dye, SC₁₂H₉N₃, crystallizing in plates, called phenylene violet, or Lauth’s v., and largely used to stain microscopic objects. Thionurate, a salt of thionuric acid. Thionuric a. [f. Gr. θεῖον + URIC], in thionuric acid, CO:2(NH.CO):CH.NH.SO₃H, formed by the action of ammonia and sulphurous acid on alloxan in aqueous solution. Thionyl [-YL], the radical (SO)″: so named in 1857 by Schiff (Annalen der Chem. und Pharm., CII. 113). Thiophene, C₄H₄S, a colorless liquid with an odor like benzene, occurring in benzene from coal-tar to the extent of about 0.5 per cent.; hence Thiophenic a., in thiophenic acid, C₄H₃S.CO₂H, derived from thiophene. Thiophenol, a colorless liquid, C₆H₅SH (= PHENOL with S in place of O), with the odor of garlic. Thiophthene [NA)PHTHENE], a colorless oily compound, C₆H₄S₂, obtained by the distillation of citric acid with P₂S₃. Thioresorcin, also Thioresorcinol, C₆H₄(SH)₂, a yellowish-grey substance, used medicinally as a substitute for iodoform. Thiosalicylic a., in t. acid, HOC₆H₄CO(SH), a brownish-yellow amorphous substance, used in medicine as an antiseptic. Thio-salt, a salt of a thio-acid, as a thiosulphate. Thiosinamine [L. sinapis mustard + AMINE] = allyl-thio-urea, C₃H₅NH.CS.NH₂, a crystalline substance produced by the action of ammonia on allyl mustard oil. Thiosulphate, a salt of thiosulphuric acid; formerly called hyposulphite. Thiosulphuric a., in t. acid, H₂S₂O₃, an acid only known in solution and soon decomposing, the salts of which are stable, and are applied in bleaching and photography; it is sulphuric acid, H₂SO₄, in which one atom of oxygen is replaced by sulphur; formerly called hyposulphurous acid. Thiotoluene [TOLUENE] = methylthiophene, C₄H₃(CH₃)S, a colorless oily compound, found as an impurity in crude toluene; two isomeric forms are known. Thio-urea, CS(NH₂)₂ or HS.C(NH₂):NH = thiocarbamide. Thioxanthone [XANTHONE], C₁₃H₈OS, crystallizing in yellow needles. Thioxene, Thioxylene [named thioxene by Victor Meyer (Ber. Deut. Chem. Ges., 1884, XVII. 789)] = dimethylthiophene, C₄H₂(CH₃)₂S, found as an impurity in xylene; there are several isomeric forms.

1854.  Kekulé in Proc. Roy. Soc., VII. 38. *Thiacetic Acid,—Sulphuretted Acetic Acid—has been obtained by me by acting on monohydrated acetic acid with tersulphide of phosphorus.

1847.  Wöhler & Liebig, in Mem. Chem. Soc., III. 303. A new organic alkali free from oxygen … which we call *thialdine … contracted from θεῖον and aldehyde.

1881.  Watts, Dict. Chem., VIII. 1952. *Thiamides … may be conveniently prepared by the action of phosphorus sulphide … on amides.

1888.  Hantzsch & Weber, in Jrnl. Chem. Soc., LIV. 256. *Thiazole is the name given to [these] isomeric compounds.

1885.  Peter, Ibid., XLVIII. 141. *Thiēnylmethylacctoxime C₄H₃S.CMe:NOH … forms a white crystalline mass.

1882.  Will, Ibid., XLII. 1088. *Thiocarbamates…. A continuation of the author’s researches.

1878.  Guareschi, Ibid., XXXIV. 860. *Thiocarbamide CS (NH₂)₂ [etc.] when oxidised by permanganate likewise yield all their sulphur in the state of sulphuric acid.

1891.  Anthony’s Photogr. Bull., IV. 397. Prof. J. E. Reynolds, who was the original discoverer of the rinsing sulphur urea, now known as thio-carbamide.

1883.  Jrnl. Chem. Soc., XLIV. 405. The use of potassium *thiocarbonate as a remedy against phylloxera. Ibid. (1887), LI. 272. The conversion of *thiocarbonyl chloride into thiocarbonyl tetrachloride by the assimilation of two atoms of chlorine takes place at ordinary temperatures. Ibid. (1877), XXXII. 869. *Thiocyanates of the acid radicles are prepared by the action of acid chlorides on dry lead thiocyanate. Ibid. (1877), XXXII. 423. Action of Nascent *Thiocyanic Acid on Alcohol. Ibid. (1857), IX. 185. *Thioformic acid crystallises from formic acid, or from boiling alcohol, in slender needles. Ibid. (1880), XXXVII. 593. A qualitative reaction, by which pentathionic acid is clearly distinguished from any other of the *thionic acids.

1839.  Thomson, British Ann., 377. *Thionurate of zinc. Ibid. *Thionuric acid.

1874.  Watts, Dict. Chem., V. 779. Thionuric acid … forms a crystalline mass, consisting of fine needles. Ibid., 780. *Thionyl. SO.—The radicle of the sulphurous compounds: e. g., sulphurous chloride, (SO)″Cl₂ = chloride of thionyl.

1883.  Meyer, in Jrnl. Chem. Soc., XLIV. 1091. A substance contained in Coal-tar Benzene … to which the author has given the name of *thiophene.

1899.  Syd. Soc. Lex., *Thiophenol,… phenyl mercaptan. Ibid. *Thioresorcin,… a popular substitution of resorcin…. Used as a dusting powder.

1853.  Ure, Dict. Arts, I. 32. *Thiosinnamine.

1881.  Piesse & Stansell, in Jrnl. Chem. Soc., XL. 207. Thiosinamine is an oily substance at 100°, but gradually solidifies when cold.

1873.  Watts, Fownes’ Chem., 198. The solution of a *thiosulphate.

1874.  Jrnl. Chem. Soc., XXVII. 771. The close relation between the thiosulphates and sulphates is shown by the formulæ—SO₂^SNa/_ONa and SO₂^ONa/_ONa.

1873.  Watts, Fownes’ Chem., 204. *Thiosulphuric Acid is scarcely known.

1874.  Jrnl. Chem. Soc., XXVII. 770. On the Constitution of Hyposulphurous (Thiosulphuric) Acid. Ibid. (1885), XLVIII. 251. A Simple Method of obtaining, *Thiotolene.

1894.  Muir & Morley, Watts’ Dict. Chem., IV. 710. Formed by adding Br to an alcoholic or cold aqueous solution of *thio-urea.

1885.  Jrnl. Chem. Soc., XLVIII. 251. A simple method of obtaining … *thioxylene.

  2.  In pharmaceutical and other terms.

  Thiobacteria, name proposed by Migula for sulphur and iron bacteria mostly found in seawater and soils. Thiocamph [CAMPH(OR], a fluid disinfectant, used for fumigation, formed by the action of sulphur dioxide on camphor. Thiocol [GUAIA)-COL], a preparation of guaiacol, used in lung diseases. Thioform [after chloroform], trade-name of a basic bismuth di-thiosalicylate, as an antiseptic for wounds. Thiogenic a. [-GEN 1 + -IC], producing sulphur, spec. applied to bacteria which produce free sulphur by the oxidization of sulphuretted hydrogen. Thiogenol, trade-name of a solution of sodium sulphonate as a medical wash. Thiolin [L. līnum flax], trade-name of a dark green substance prepared from linseed oil by the action of sulphur; hence Thiolinic acid. Thiosapiol, -sapol [L. sapo soap], -savonal, trade-names of soap containing sulphur in chemical combination. ǁ Thiothrix [Gr. θρίξ hair], a genus of sulphur bacteria found in sulphur springs.

1900.  A. C. Jones, trans. Fischer’s Str. & Funct. Bacteria, 65. The sulphur bacteria, *Thiobacteria, whose cells are often crammed full of spherical refringent masses of pure sulphur, occur in nature in places where free sulphuretted hydrogen is present. Ibid. Thiobacteria can be found at any time of the year, but are most abundant in the early spring and late autumn.

1899.  Syd. Soc. Lex., *Thiocamph … on exposure evolves sulphur dioxide in steady fumes. Ibid. *Thioform … a light yellowish powder, without odour or taste … has … been introduced into surgery with promising success.

1910.  Brickdale, Guide Newer Remedies, 60. A dithiosalicylate … has been … named Thioform.

1894.  Remington, Pract. Pharm. (ed. 3), 1433. *Thiolin. Salts of thiosulphonic acid. Salt of thiolinic acid. Sulphonated and sulphurated linseed oil.

1899.  Syd. Soc. Lex., Thiolin, thiolinic acid. Ibid. *Thiosapiol, a sulphuretted soap, containing 10 per cent. of sulphur, obtained by heating sulphur and oleic acid together…. A successful application to many skin diseases.