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2P2
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faces, Poo, Poo, OP, and +

The a-dibromide is not converted into the B-compound or vice versa by prolonged heating at 130°, and it is somewhat more soluble in alcohol and ether than its isomeride. Hot dilute nitric acid dissolves the a-dibromide, and the nitrate on cooling separates in colourless crystals; whilst the B-derivative, when similarly treated, is obtained in a form resembling that of recently precipitated silica. Both compounds yield zincochlorides, which crystallise in colourless needles, and melt almost simultaneously at about 250°. The dibromides separated from the nitrates or zinc salts melt at their original temperatures, although both are converted into the same dehydrocinchine on treatment with alcoholic potash.

Cinchonine, on bromination in a mixture of alcohol and chloroform at the ordinary temperature, also yields two dibromides, and these can be separated by the method employed with the a-cinchine-derivatives. The a-dibromide, the isomeride already described (lor. cit.), crystallises with 1 mol. H2O, whilst the B-compound crystallised under similar conditions is always anhydrous. Both derivatives yield sparingly soluble salts, which seem to crystallise differently, and the hydrobromide of the B-compound is more readily soluble in hot, dilute hydrobromic acid.

Chinine dibromide, CH22Br2N2O, is obtained by the action of bromine dissolved in chloroform on a chloroform solution of chinine. The hydrobromide, CH22Br2N,O,2HBr + 2H,O, is a citron-yellow, crystalline mass, sparingly soluble in cold water, alcohol, and excess of hydrobromic acid. When the base is heated with alcoholic potash for seven to eight hours, it yields dehydrochinine, C20HN2O, which, after repeated recrystallisation of its tartrate, is obtained as a thick oil, slowly solidifying to a mass of long needles. It crystallises with at least 3 mols. H2O, melts above 40°, and is almost insoluble in water, readily soluble in alcohol, wood-spirit, and ether. The solution in sulphuric acid has an intense greenish-blue fluorescence, and on the addition of chlorine and ammonia becomes green. The hydrobromide forms yellow crystals, and is readily soluble in water, less so in alcohol.

Hydrochloroquinine, C20H25 CIN2O2, is formed when quinine hydrochloride is treated with 10 times its weight of hydrochloric acid saturated at -17°, and allowed to remain for a week at the ordinary temperature; the base is precipitated by ammonia and purified by conversion into its nitrate, which is then repeatedly crystallised from very dilute nitric acid. It melts at 186-187°, and is insoluble in water, but crystallises well from ether and alcohol. The nitrate forms colourless crystals, is very sparingly soluble iu dilute nitric acid, and its aqueous solution fluoresces an intense blue, and gives the green coloration on treatment with chlorine-water and ammonia. Hydrobromoquinine, CH2BrNO2, obtained by the action of hydrobromic acid saturated at -17°, on quinine dihydrobromide in the cold, yields a well-crystallised acid hydrochloride and hydrobromide; the latter has the composition C2H25 BгN2O2,2HBr. Neither the hydrochloro- nor the hydrobromo-quinine are soluble in aqueous potash, but on treatment for 50 days at the ordinary temperature with 10 times

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its weight of hydrobromic acid saturated at -17°, acid quinine hydrobromide yields a compound, C2H27BгзN2O2, which dissolves completely in dilute aqueous potash, and is precipitated from the solution by carbonic anhydride. It is soluble in ether, and its solution in sulphuric acid shows no fluorescence.

Hydrochlorocinchonine, C19H2CIN2O, obtained in a similar manner from cinchonine hydrochloride, melts at 212-213°. The dihydrochloride crystallises in well-formed prisms. When the base is heated with alcoholic potash for 10 to 12 hours, it loses chlorine and seems to be converted, like the hydrobromo-derivative, into isocinchonine and a small quantity of cinchonine. Hydrobromocinchonine, C19H23 BrNO, prepared similarly from cinchonine dihydrobromide, is identical with the base obtained by Skraup (Annalen, 201, 324), and when heated with silver oxide, yields as stated by him silver bromide and an organic base of peculiar odour recalling that of acetamide and piperidine; this change, however, does not occur in the cold. The same odour is produced when hydrobromocinchonine is heated with dilute sulphuric acid and lead dioxide or manganese dioxide with the addition of some silver sulphate, and the product afterwards saturated with an alkali; cinchonic acid is also formed during the oxidation with manganese dioxide.

Isocinchonine, C19H22N2O, is formed when hydrobromocinchonine (1 part) is heated in a reflux apparatus with potassium hydroxide (2 parts), and alcohol (30 parts), until the base is free from bromine. At the same time, cinchonine is also obtained, and the two bases are separated by treatment with ether; the small quantity of ciuchonine is then removed by converting the residue obtained from the ethereal solution into the zincochloride, and crystallising from aqueous zinc chloride, in which solvent the isocinchonine compound is sparingly soluble in the cold. Isocinchonine melts at 125-127°, and, unlike cinchonine, is extremely soluble in alcohol, ether, benzene, carbon bisulphide, chloroform, and ethyl acetate. With acids, it yields for the most part soluble salts, and when carefully heated in small quantity volatilises without decomposition. The zincochloride, C19H22N2O,2HCl,ZnCl2, crystallises in small, colourless needles and

melts at 260-262°.

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Hydrobromocinchine, C9H1BrN,, obtained by dissolving cinchine in 10 times its weight of hydrobromic acid saturated in a freezing mixture of ice and salt, and allowing the solution to remain for two days, crystallises from ether in monoclinic forms; a b c = 0.85412:10-82801; 8: 63° 7'; and is isomorphous with x-cinchine dibromide (m. p. = 113°). It melts between 105° and 116°, and dissolves readily in alcohol, ether, &c., but only sparingly in light petroleum. The zincochloride crystallises well. Cinchine does not seem to form addition compounds with 2 mols. of a haloïd acid or 2 mols. of bromine. 6-Cinchine dibromide, for example, when treated with bromine in chloroform solution, yields a perbromide, which is converted into the unaltered base on the addition of sodium hydrogen sulphite; whilst cinchine, when heated with concentrated hydrobromic acid at 100, yields a base which could not be crystallised, and which seems to contain somewhat less bromine than hydrobromocinchine.

Hydrobromodehydrocinchonine, CH2BrN2O, is prepared by allowing a solution of dehydrocinchonine in concentrated hydrobromic acid to remain for eight days. It forms anhydrous crystals, and melts at about 235°. The corresponding dehydrocinchonine dibromide could not be prepared by the action of bromine on dehydrocinchonine in chloroform solution, but under these conditions a crystalline base melting at 228° is obtained, whose composition approximates to that of a monobromodehydrocinchonine, C19H19BrN2O.

Pyridine-derivatives do not seem to form halogenated compounds when treated with hydrobromic acid saturated at -17°; thus pyridine and quinoline are unaltered in the cold or when heated at 140° with the acid; tetrahydroquinoline is unaffected in the cold, and the tertiary base, C1HN, obtained by Fischer and Steche (this vol., pp. 588 and 976), which is probably a partially hydrogenated quinoline-derivative, and methyllepidone are similarly unattacked. From considerations. based on the oxidation of cinchonine and quinine with chromic acid, the authors regard it as improbable that the quinoline-group in the molecule is hydrogenated, and since these alkaloids, together with cinchine and dehydrocinchonine, readily combine with a molecule of hydrogen bromide or chloride, it is evident that the addition must occur in the complex C10H16NO, which seems to have the same constitution for both alkaloïds. W. P. W.

Preparation of Aconitine. By J. WILLIAMS (Pharm. J. Trans. [3], 18, 238-240).-The dried, coarsely ground root of Aconitum napellus is exhausted with amyl alcohol, the solution is agitated with very dilute sulphuric acid (1: 600), the alkaloid is precipitated from the acid by sodium carbonate, and then dissolved either in alcohol or in ether, and allowed to crystallise. The necessary precautions are detailed in the original. R. R.

Curare. By R. BOEHM (Chem. Centr., 1887, 520).-Besides the active principle, curarine, contained in curare, the author has found a second base, curine, which has no action on the organism. This is a white, microcrystalline substance, soluble in water, readily soluble in alcohol, chloroform, and in dilute acids. The solutions give a thick, white precipitate with metaphosphoric acid.

The separation of curarine is effected by means of platinic chloride; it is a yellow substance. 0.35 mgrm. is sufficient to kill a rabbit weighing 1 kilo.; 0·003—0·005 mgrm. will kill a frog. N. H. M.

The Alkaloïds of Coca Leaves. By O. HESSE (Pharm. J. Trans. [3], 18, 71).—The author dissents from Stockman's opinion that amorphous cocaïne is a solution of true cocaïne in hygrine. Coca leaves finely divided, and extracted by ether, give on agitation of the ethereal solution with hydrochloric acid, a liquid which although at first non-fluorescent, after a time becomes distinctly fluorescent, thus showing that hygrine is a product of subsequent decomposition. The amorphous bases easily separated from cocaïne, give a platinum salt containing 18:44 per cent. platinum; but these are not homogeneous, for the author has been able to separate by fractional precipitation a

well-defined base, which he has called cocamine. This has the same composition as cocaïne, CHNO; it dissolves readily in ether, alcohol, or chloroform, and on evaporation remains in an amorphous condition. Its hydrochloride, CH2NO,,HCl, is amorphous, neutral, and soluble in water and alcohol; when dried at 120° it loses weight, and eventually becomes insoluble in cold water. R. R.

Separation of Hygrine from Cocaïne. By W. C. HOWARD Pharm. J. Trans. [3], 18, 71). In a liquor containing cocaïne, hygrine, &c., neutralised by hydrochloric acid, platinum chloride produces a doubtfully semi-crystalline precipitate, part of which was insoluble in water at 80°. The base of the soluble part, the author identified as cocaïne. The insoluble platinum salt was found by two experiments to contain platinum, 18.48 per cent. and 18.6 per cent., and when decomposed in the usual way, it yielded a base that gave no crystallisable chloride, did not smell of trimethylamine, had a bitter taste, and was not decomposed by hot water; in which characters it differs from hygrine as described by Lossen (Annalen, 121, 374). Therefore, either Lossen's base was impure, or the author's is a different one, and amorphous cocaïne may have no existence, but may be merely a solution of cocaïne in the base above described.

R. R.

Higher Homologues of Cocaïne. By F. G. Novy (Pharm. J. Trans. [3], 18, 233-234).-These substances were prepared by heating benzoylecgonine with the homologues of methyl iodide.

Ethylbenzoylecgonine, CiH1sEtNO,, forms white, silky crystals or large monoclinic prisms, melts at 107-108, and resolidifies at 90°. The hydrochloride crystallises in colourless needles or prisms; the platinochloride, (CHNO.)2, H2PtCle, forms yellow, rhombic plates; the aurochloride is obtained as a voluminous, yellowish-white precipitate. Bromethylbenzoylecgonine, prepared from benzoylecgonine and ethylene bromide, C2H.Br.CHINO,, could only be obtained as a colourless syrup.

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Propylbenzoylecgonine, C16H18PrNO, crystallises in silky needles or colourless prisms, melts at 78-79.5°, and resolidifies at 65°; it has a very bitter taste and is a powerful anaesthetic.

Isobutylbenzoylecgonine, CH, C16H18NO4, crystallises in short, colourless prisms, melts at 61-62°, has an intensely bitter taste and powerfully anesthetic properties. The hydrochloride forms a hard, vitreous, yellow mass. A. J. G.

Absorption of Light by Oxyhemoglobin. By F. KRÜGER (Zeit. Biol., 24, 47-66).-The results of the present investigation corroborate Kupffer's statement that the absorption coefficient of oxyhemoglobin increases each time the oxyhæmoglobin is recrystal

lised.

In determining the absolute amount of hæmoglobin in blood by means of the spectrophotometer, it is best only to recrystallise once, as each recrystallisation increases the error of observation.

The use of dilute ammonia in the preparation of hæmoglobin

crystals as recommended by Schmidt increases their solubility in J. P. L.

water.

Action of Reducing Agents on Hæmatin and Occurrence of the Products of Reduction in Pathological Urine. By C. LE NOBEL (Chem. Centr., 1887, 538).-When hæmatin is reduced in acid or alkaline solution, iron is eliminated and hematoporphyrin is formed. Afterwards hæmatoporphyroidin (differing from hæmatoporphyrin in solubility but nearly identical in its spectroscopic properties) is formed. The hæmatoporphyroïdin is then transformed into MacMunn's urohæmatin, to which the author gives the name isohæmatoporphyrin and lastly urobilinoïdin is formed. This resembles urobilin in some of its properties; it can readily be converted into isohæ matoporphyrin and hexahydrohæmato porphyrin. Maly's hydrobilirubin is not identical with Jaffe's urobilin. There is no connection between the colouring matter of blood and Jaffe's urobilin. In some pathological conditions, in which it may be assumed the colouring matter of blood has decomposed, the above products of reduction occur in urine. N. H. M.

Hemialbumose. By AXENFELD (Arch. Pharm. [3], 25, 696697).-Pyrogallol is a better precipitant for this albuminoïd than either ammonium sulphate, or nitric or picric acids, as more dilute solutions can be employed. Its sensibility is 10 times that of nitric acid. The author has detected hemialbumose in meal, bread, leguminous seeds, milk, and cheese. The usual method of detection consists in the precipitation of hemialbumose at the ordinary temperature by nitric acid, and solution of this precipitate on warming, but the pyrogallol test succeeds where this test fails. In milk after precipitating the caseïn by acetic acid, and the albumin and para globulin by magnesium sulphate, 0·13 per cent. of hemialbumose was found in cow's milk and 0.29 per cent. in human milk. All animal tissues excepting nerve and muscle substance contain hemialbumose. J. T.

Physiological Chemistry.

Glycogen. By A. CRAMER (Zeit. Biol., 24, 67-104).-The potash process for estimating glycogen recommended by Külz, has enabled the author to make an exhaustive study of the occurrence and relative distribution of glycogen in various tissues and organs. The following are some of the chief conclusions arrived at :

From the result of many determinations, the process leaves little to be desired from the point of accuracy.

The glycogen in the muscular structure of both halves of the body is found, as would be supposed from theoretical considerations, to be equal. In the liver, the glycogen is equally distributed throughout : for the estimation of the glycogen therefore it is only necessary to

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