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and ether. The calcium, lead, and copper salts are described. The acid readily loses water, forming first the monobasic acid,

C16H33 CH(COOH)·O·CO·CH(OH)C16H33,

.CO.O.

and by further loss the anhydride, CH3CH<O.CO>CH·C16H13. It is an exceedingly difficult matter to isolate the products of the action of sulphuric acid on the tri-oleïn. When those substances are carefully brought together in the ratio of 3 mols. of the former to 1 mol. of the latter, the chief final product is a monobasic acid of the formula C16H33 CH(SO,H)COO-C2H2 (O-CO-CHICH-CH31)-O-CO-CH(OH)-C16H33. The barium and copper salts form oils which are readily decomposed by potash. G. T. M.

Constitution of Acetoacetic, Succinosuccinic, and Quinonehydrodicarboxylic Acids. By A. GEUTHER (Annalen, 244, 190— 221). The author maintains that the acetoacetic and succinosuccinic acids are not ketonic acids, and he points out that the results obtained by Israel (Abstr., 1886, 334, and 1887, 915) and by Isbert (Abstr., 1886, 1009) are evidence in favour of the formula CH·C(OH):CH·COOEt for ethyl acetoacetate.

The author criticises Ebert's experiments (Abstr., 1885, 1122) on the constitution of succinosuccinic acid, and complains that Baeyer has incorrectly represented his views on this subject (Abstr., 1886, 223 and 445). W. C. W.

Methyl Acetocyanacetate. By A. HALLER and A. HELD (Compt. rend., 106, 210-213).-Methyl acetocyanacetate, CN-CHAC.COOMe, was obtained in the same way as the ethyl-derivative (Abstr., 1887, 799 and 1029), by the action of cyanogen chloride on a mixture, in molecular proportions, of methyl acetoacetate and sodium methoxide, dissolved in excess of methyl alcohol. It crystallises from ether in silky needles which melt at 46.5° and dissolve readily in ether or alcohol, but are insoluble in water.

The sodium-derivative, C,H,NaNO, is obtained by the action of sodium carbonate in alcoholic solution. It forms white, silky, anhydrous crystals soluble in water and alcohol. The calcium-derivative, prepared in a similar way, forms bulky, transparent, efflorescent crystals containing 6 mols. H2O.

Methyl acetocyanacetate can also be prepared by mixing a solution of methyl sodiocyanacetate in methyl alcohol, with a solution of acetyl chloride in ether, and heating at 40-50° for some hours; the product is then treated with acidified water, submitted to fractionation in a vacuum, and the ethereal salt converted into its calcium-derivative.

If sodium ethoxide is used in place of the methoxide in the first method, the product is an uncrystallisable mixture of ethyl and methyl acetocyanacetates which cannot be separated by fractionation. It is evident that double decomposition takes place between the ethoxide and the methyl acetocyanacetate with formation of a mixture of methyl and ethyl salts. Purdie has observed a similar reaction in the case of the ethereal salts of fumaric, oxalic, and other acids (Trans.,

1887, 627), and Peters in the case of methyl and ethyl acetoacetates (this vol., p. 254). C. H. B.

Compounds of Ethylidenelactic Acid. By R. LEIPEN (Monatsh. CHMe O.

Chem., 9, 45-51).—Ethylidene lactate, <CO- >CHMe, is obtained by heating acetaldehyde with an excess of lactic acid (previously partially converted by heating at above 150° into anhydride and lactide), for some hours at 120° to 170°. The product is distilled, and the portion boiling between 50° and 200° is treated with potassium carbonate, when the ether separates. It is a clear liquid of a slightly ethereal odour, boils at 150-151.5°, and dissolves in a large amount of water. Hot water decomposes it quickly into its constituents. Lactanilide, C,HNO2, is prepared by heating lactic acid and aniline for six to seven hours on a sand-bath at such a temperature that water is given off, the liquid not being allowed to boil. The product is extracted with boiling water, and the filtered extract concentrated by evaporation. It crystallises in colourless plates, melting at 58°, readily soluble in alcohol, ether, aud chloroform, but insoluble in light petroleum. Boiling dilute aqueous soda decomposes it.

Lactoparatoluide, C10H13NO2, prepared in a manner similar to the anilide, crystallises in needles, melting at 102-103°, very sparingly soluble in cold water. The orthotoluide is purified by allowing the solution in benzene to evaporate slowly, when it separates as a white powder, melting at 72°. Both toluides resemble the anilide in solubility. N. H. M.

Galactosecarboxylic Acid. By MAQUENNE (Compt. rend., 106, 286-288). If a solution of galactose is mixed with hydrocyanic acid at the ordinary temperature, its rotatory power gradually disappears, and the liquid becomes brown. A concentrated solution deposits a yellowish, slightly soluble, crystalline precipitate, especially if the excess of hydrocyanic acid is expelled by a current of air. This precipitate is the amide of galactosecarboxylic acid, C,H,NO,, and may be purified by crystallisation from boiling acetic acid, from which it separates in slender, yellowish, microscopic needles, slightly soluble in water, and almost insoluble in alcohol, but soluble in boiling acetic acid. It melts at 194° with partial decomposition.

When boiled with water, and especially with alkalis, the amide is readily decomposed with liberation of ammonia and formation of a salt of the acid. The formation of an amide shows that the action of hydrocyanic acid on galactose is not strictly analogous to its action on levulose.

vacuum.

Galactosecarboxylic acid, CHO,, is most readily prepared by decomposing its barium salt with sulphuric acid, and evaporating in a It forms slender needles which melt at 145° and decompose at a higher temperature. It has a distinctly acid taste and reaction, and is soluble in water, but almost insoluble in absolute alcohol. Barium galactosecarboxylate, obtained by the action of barium hydroxide on the amide, forms long, slender, microscopic needles, which dissolve slowly in water, and are insoluble in alcohol. It is slightly dextrogyrate [a] = 5° 30'.

This action of hydrocyanic acid shows that galactose has an aldehydic or ketonic function. C. H. B.

Action of Hydrocyanic Acid on Galactose. By H. KILIANI (Ber., 21, 915-919; compare preceding Abstract).-When finely powdered galactose (30 grams), moistened with water (6 c.c.), is treated with the calculated quantity of 50 per cent. hydrocyanic acid and a few drops of ammonia, and allowed to remain at the ordinary temperature in a perfectly closed flask, solution of the carbohydrate occurs and at the end of eight hours a rise in the temperature of the liquid takes place accompanied by the separation of the amide of galactosecarboxylic acid in small, white needles. The yield amounts to 40-50 per cent. of the weight of the galactose employed.

Galactosecarboxylic acid, CHO COOH, is prepared from the amide by digesting it with milk of lime at 100° to expel ammonia, decomposing the resulting basic calcium salt with oxalic acid, and evaporating the filtrate over sulphuric acid in a vacuum. It crystallises in slender needles, and melts at 145° with the loss of 2 mols. H2O and the formation of an amorphous anhydride; a similar decomposition also occurs when the aqueous solution of the acid is boiled for some time. The potassium salt, 2CH3O6 COOK + H2O, crystallises in colourless prisms or needles, and fuses at 110° with the loss of its water of crystallisation; the calcium salt was also prepared. On reduction with concentrated hydriodic acid and amorphous phosphorus for 1 hours in a reflux apparatus, the acid is converted into the lactone of normal 7-hydroxyheptylic acid (b. p. = 231°), and a very small quantity of normal heptylic acid, consequently galactosecarboxylic acid, like dextrosecarboxylic acid, must be regarded as a normal hexahydroxyheptylic acid. W. P. W.

Synthetical Experiments in the Uric Acid Series. By R. BEHREND and O. ROOSEN (Ber., 21, 999—1001). Further experiments have shown that one of the products obtained by the reduction of nitrouracil (Behrend, Annalen, 229, 39), is the ureïd of an a-ß-diNHÁCH, hydroxyacrylic acid or isobarbituric acid, CO<NH.CO.

C.OH.

Hydroxylamine does not act on this compound, but when it is boiled with acetic anhydride, an acetyl-derivative is formed which crystallises from hot water in the form of sparingly soluble, colourless, concentrically grouped prisms. When isobarbituric acid is treated with bromine-water, it yields an acid which has the same composition as dialuric acid. This substance crystallises in solid prisms with 2 mols. H2O, the first of which passes off at 100°, the second at 140-150°, apparently with slight decomposition. It differs from ordinary dialuric acid in crystalline form, water of crystallisation, and in its ready solubility in water as well as in its stability towards oxidising agents, it may therefore be termed isodialuric acid, and its formula is probably either

[blocks in formation]

NH.C(OH) C.OH.

>CO or CO<_

NH.CO

This acid is also formed by the action of bromine-water on amido

uracil and hydroxyxanthine. It is readily acted on by acetic anhydride. When heated with carbamide and concentrated sulphuric acid, a white, crystalline powder is obtained, the analysis of which agreed with that of uric acid. The compound is an acid, decomposes carbonates and gives the murexide reaction; it reduces Fehling's solution, and a dilute solution in sodium carbonate blackens paper moistened with silver nitrate. It crystallises from hot water in the right-angled plates which are characteristic of uric acid. The solubility in water at 18° was found to be 1:9000. The sodium salt, C1H,NO,Na, H2O, crystallises in microscopic needles. The barium salt, (C,H,NO3)2 Ba,2H2O, is amorphous.

F. S. K.

Trimethyluracil. By M. HAGEN (Annalen, 244, 1—19).—The preparation of trimethyluracil by the action of methyl iodide on the potassium salt of methyluracil at 150°, has been described by Behrend (Abstr., 1886, 339). The excess of methyl iodide is removed from the crude product by distillation, and the residue is dissolved in water. The solution is agitated with chloroform, and sodium carbonate is added to the chloroform extract to remove free iodine. The residue which is left after distilling off the chloroform is treated with ether; the trimethyluracil slowly dissolves leaving a small residue of methyluracil dihydride.

Trimethyluracil crystallises in rhombic plates and melts at 109°. It does not form salts with acids or with bases. It is decomposed by barium hydroxide at 200°, yielding methylamine, and carbonic and acetic acids. Its constitution is probably represented by the formula NMeCMe CH. Benzyl chloride acts on the potassium salt of methyl uracil, forming benzylmethyluracil, a crystalline compound melting at 232—233°.

CO NMe CO

Dry bromine or a solution of bromine in carbon bisulphide acts on dry trimethyluracil, forming a compound of the composition CH,NO,Br. Dibromhydroxytrimethyluracil is obtained as a white powder when bromine is added to an aqueous solution of trimethyluracil. It is deposited from a hot aqueous solution in rhombic plates, and melts at 163° with decomposition. It is decomposed by prolonged boiling with alcohol, yielding brometrimethyluracil. This substance melts at 126°.

Dichlorhydroxytrimethyluracil melts with decomposition at 143-144°. It is converted into chlorotrimethyluracil by the action of stannous chloride.

Amidotrimethyluracil is formed by acting on bromotrimethyluracil with strong ammonia at 140°. It melts at 166-167°, is soluble in water, and forms deliquescent salts. The hydrochloride interacts with an excess of potassium cyanate, forming trimethylhydroxyxanthine in small quantities; this crystallises in microscopic prisms.

W. C. W.

Cyanuric Derivatives of Taurine. By B. RATHKE (Ber., 21, 874-877).-When a solution of the hydrochloride of ethylenethiammeline (Abstr., 1887, 650) is treated with chlorine, a nearly insoluble compound separates in silvery plates; this seems to be an inner

anhydride of taurammeline of the formula |

N.C(OH) N C2H ̧ ̧

SO2;

C(NH2):N CN

it dissolves in alkalis, presumably with conversion into the sulphonic acid, but is reprecipitated on addition of acids; with silver nitrate, it gives a white precipitate sparingly soluble in ammonia.

Taurodiammeline, COHN,S2Os, is formed at the same time as the above compound, but is formed alone when the ethylenethiammeline is oxidised with nitric acid. It forms slender, transparent prisms, sparingly soluble in cold water; when heated, it begins to turn brown at 270°, but is still not melted at 290°. It has very marked acid characters; the salts with the alkalis and alkaline earths are readily soluble.

Taurammelide, NH.C<NC(OH)>N-C2H, SO,H, is obtained on boiling the preceding compound with baryta-water; it forms sparingly soluble crystals, and melts at 265-270° with decomposition.

A. J. G. Vapour-density of Aluminium Methide. By E. LOUISE and L. Roux (Compt. rend., 106, 602—603).—The aluminium methide was prepared by the action of mercuric methide on excess of aluminium, and was redistilled over aluminium in pure and dry nitrogen. It is a colourless mobile liquid which boils at 140°, and is much less stable than aluminium ethide. The vapour-density was determined by Meyer's method at different temperatures.

Temperature....
Vapour-density.

.......

182° 216° 310° 340° 440° 5.1 4.75 4.6 2.4 1.8

At 50° above the boiling point, the vapour-density agrees with the formula Al,Me, but as the temperature rises, the compound gradually decomposes until at 440° the vapour-density is only 18. The products of decomposition are metallic aluminium and gaseous paraffins and olefines. C. H. B.

25 Dibromocymene. By A. CLAUS (J. pr. Chem. [2], 37, 14-27; see Abstr., 1880, 632; Ber., 13, 905, 972).-By direct bromination of paracymene, only one dibromoparacy mene,

CH2MePrBr2 [Me: Pr: Br2 = 1 : 4 : 2 : 5],

is obtained, which when nitrated with a mixture of nitric and sulphuric acids furnishes three nitro-derivatives, melting at 149°, 142°, and 89° respectively. The product melting at 149° has the formula

C&PrMe (NO2)2Br2 [(NO2)2 = 3 : 6],

crystallises from alcohol in colourless needles, and is characterised by great stability. It is only imperfectly decomposed by heating with fuming nitric acid in sealed tubes at 280°, and is scarcely attacked by long-continued boiling with aqueous or alcoholic potash. The compound melting at 142° crystallises from ordinary solvents in yellow needles or prisms, and sublimes in small scales. It is a dibromodinitrotoluene, CHMe (NO2)2Br2 [Me: Br2: (NO2)2=1:2:5:4:6], and is readily attacked by potash. With aniline, it readily forms the compound NHPLC,ĤMeBr(NO2)2, crystallising in glistening

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