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2. The azines, in which the nitrogen-ring is in union with two other

N

rings, of these compounds, phenazine, C.H.C.H., is the first member, the higher members being named

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Nitrotolylglycine and Oxydihydrotoluquinoxaline. By R. LEUCKART and A. HERRMANN (Ber., 20, 24-31. Compare Hinsberg, Abstr., 1886, 82, Plöchl, and also the authors, ibid., 351).—The barium, ammonium, and lead salts of orthonitrotolylglycine (nitrotoluidoacetic acid) are described. The ethyl salt crystallises in broad, yellow needles, melts at 65°, and is readily soluble in benzene, light petroleum, &c. NHCH,

Chlordihydrotoluquinoxaline, CH<N: CCi>, is prepared by heating oxydihydrotoluquinoxaline with phosphoric chloride at 140150°; it forms colourless needles, melts at 77°, has a quinoline-like odour, and is insoluble in water, very readily soluble in alcohol, ether, benzene, and light petroleum. It has feeble basic properties. When heated with alcoholic potash, the chlorine-atom is displaced with formation of the exthoxide, CH<N:C(OEt) -NHCH,

This crystallises in

brittle, silky needles, melts at 67°, and is readily soluble in hot water, alcohol, ether, benzene, or light petroleum. The corresponding methoxide melts at 71°. When the chloride is heated in acetic acid solution with hydriodic acid at 240°, amongst other products a few drops of an oil of quinoline-like odour was obtained; this probably is dihydrotoluquinoxaline, but the amount was too small for investigaA. J. G.

tion.

Conyrine Platinochloride. By T. LIWEH (Ber., 20, 67-68).— The author has submitted synthetical conyrine platinochloride (Abstr., 1887, 160) to a crystallographic examination, and gives results which show that the crystals are precisely similar in form to those of the conyrine platinochloride obtained from natural conine.

W. P. W.

Hydrastine. By M. FREUND and W. WILL (Ber., 20, 88–95).— In this paper, the authors substitute the formula C2HNO, for that previously ascribed to hydrastine (this vol., p. 174). They have examined the base hydrastinine, CuHNO2 + H2O, obtained together with opianic acid when hydrastine is treated with oxidising agents. Hydrastinine forms white crystals, melts at 116-117°, fusion, however, occurring if it be kept at 100° for some time, and is soluble in benzene, ethyl acetate (these solvents produce a partial decomposition), light

petroleum, ether, and water; the aqueous solution is strongly alkaline and intensely bitter. Like cotarnine, of which it is the next lower homologue, hydrastinine crystallises from all solvents with 1 mol. H2O; this, however, is not present in its salts. The hydrochloride, CHNO2,HCl, crystallises in feebly coloured needles, melts at about 212° with decomposition, and is readily soluble in alcohol and water; the aqueous solution shows a feeble fluorescence, and is optically inactive. The sulphate, CHNO2, H2SO4, forms yellow crystals showing a green fluorescence, and is soluble in alcohol. The dichromate, C1H1NO2,H2Cr2O7, crystallises in slender, goldenyellow needles, and is soluble in water. The methiodide, C1HNO2, Mel, crystallises in slender, yellow needles showing a vitreous lustre, and is soluble in alcohol and water. The platinochloride, CHNO2, H2PtCle, CHNO2,H,PtCl, and the aurochloride form yellow crystals, whilst with potassium ferricyanide a compound crystallising in reddish-brown needles is

obtained.

Hydrohydrastinine, CHINO2, is formed when hydrastinine is reduced with zinc and hydrochloric acid. This base forms white crystals, melts at 66°, and is readily soluble in ether, alcohol, benzene, carbon bisulphide, ethyl acetate, and acetone; the picrate crystallises in yellow needles. The hydrobromide, CH,NO2,HBr, forms tufts of small, white needles, and, like the hydrochloride, is sparingly soluble

in water.

Hydrastinic acid, C,H,NO,, is obtained by boiling hydrastine with dilute nitric acid until potassium hydroxide no longer precipitates the product. The acid is crystalline, melts at 232° with decomposition, is soluble in alcohol and water, and resembles apophyllic acid (Abstr., 1881, 110) in its properties. The silver salt, C.H.NO.Ag. crystallises W. P. W.

in needles.

14

Action of Phosphorus Pentachloride on Substituted Formamides and on Piperidine-derivatives. By O. WALLACH and F. LEHMANN (Annalen, 237, 236-260).-The hydrochloride of a base of the composition C,HN2 is obtained by adding phosphoric chloride to a solution of diethylformamide in chloroform. The resulting phosphorus oxychloride is distilled off under reduced pressure, and the residue kept at a temperature of 100° for two hours. On the addition of platinum chloride to the alcoholic solution of the product, the platinochloride, (C,HN2)2, H2PtCl, is precipitated. The intermediate product, C10H19CIN2, previously described by Wallach (Abstr., 1881, 719) could not again be isolated.

Diethylformamide forms two platinochlorides of the composition (NEt COH),H,PtCl, and (NEt2 COH)2, H2PtCl + 2H2O.

Piperidine also forms two platinochlorides. When platinum chloride is added to a concentrated aqueous solution of piperidine hydrochloride, an anhydrous salt, (CHN)2, H2PtCl, is precipitated. But if this salt is recrystallised from boiling alcohol mixed with a small quantity of hydrochloric acid, orange, needle-shaped crystals containing 1 mol. of alcohol are obtained, (CHN)2, H2PtCl + Č2HO. The anhydrous salt melts at 198-200°, the alcoholic salt at 191°, both with decomposition.

Ethyl piperidyloxamate, C,NH, CO-COOEt, is obtained as a colour. less, oily liquid, heavier than and insoluble in water, by boiling a mixture of piperidine and ethyl oxalate for several hours. The product boils at 283-290°. It is converted into the oxamide by ammonia. The oxamide, C,NH10 CO-CONH2, is deposited from a hot aqueous solution in monoclinic prisms; a:b: c = 0·66182: 1:0·53426, B= 50° 53·5'. It is soluble in alcohol and melts at 126-127°, and is converted into the nitrile of piperidyloxamic acid, NC•CO·C,NH10, by the action of phosphoric anhydride.

Piperidyloxamic acid, C,NH CO-COOH, is conveniently prepared by adding a concentrated alcoholic solution of sodium ethoxide to an alcoholic solution of ethyl piperidyloxamate. The free acid is deposited in needle-shaped crystals on the addition of hydrochloric acid to the solution of the sodium salt. It dissolves freely in alcohol and chloroform, and melts at 128-129° with evolution of carbonic anhydride. Piperidyloxamic chloride is decomposed by distillation, yielding carbonic oxide and piperidyl carbamic chloride. The carbamic chloride boils at 237-238°, and is decomposed by warm water. With aniline it yields phenylpiperidylcarbamide,

[blocks in formation]

a white crystalline substance melting at 171-172°.

Dipiperidyl carbamide melts at 42-43°, and boils at 296-298°. It is freely soluble in ether, alcohol, chloroform, and in acids.

Formopiperidide, HCO CNH10, prepared by heating piperidylcarbamic acid in a flask with a reflux condenser, is a colourless liquid boiling at 222°. The aqueous solution reduces silver salts and Fehling's solution, and forms a crystalline double salt with mercuric chloride, HCO C&NH10, HgCl2.

The hydrochloride is precipitated in deliquescent needles when hydrogen chloride is passed into a solution of formopiperidide in absolute ether. If the hydrochloride is dissolved in a small quantity of water, and mixed with alcohol and platinum chloride, a crystalline platinochloride is deposited which has the composition

(C,NH10 COH), H2PtCl,

and is analogous to that obtained from diethylformamide. A complicated reaction ensues when phosphoric chloride acts on formopiperidide. The authors suggest that piperidine and the amidochloride, CNH CCl2H, are formed in the first instance. These substances react on each other, yielding the compound CHCI(CNH10)2, which unites directly with platinum chloride to form the salt (C1H2N2Cl)2, PtCl. W. C. W.

Ptomaïnes. By H. BECKURTS (Arch. Pharm. [3], 24, 1041-1065). -The detection of poisonous alkaloïds in forensic and similar cases is greatly increased in difficulty owing to the formation of ptomaïnes from albuminoïd substances of animal or vegetable origin, more especially as the ptomaïnes in their general chemical reactions bear great resemblance to the vegetable alkaloids. It has repeatedly occurred in criminal cases, that the two classes of compounds have

been confounded, even by experts. All the basic nitrogenous products which result from the action of bacteria, whether of disease or decomposition, must be considered as ptomaïnes; and perhaps also certain definite poisonous basic substances, the leucomaïnes, which according to Gautier are formed during life in man and the higher animals.

Until very recently, only ptomaïnes of unknown composition had been isolated, and in all cases by the methods of Stas-Otto and Dragendorff. It is mainly to Brieger's investigations during the past four years, that we are indebted for a more accurate knowledge of the composition of these compounds. (For Brieger's method see Abstr., 1885, 278.) From decomposing flesh, Brieger obtained neuridine, CH1N3, and neurine, C,H,NO. From decomposing fish he obtained a poisonous isomeride of ethylendiamine, possibly ethylidenediamine, C2H,(NH2)2, muscarine, C,HNO3, and the physiologically inactive gadinine, CH17NO2. Fully decomposed cheese yielded neuridine. Decomposing glue gave neuridine, dimethylamine, and a muscarinelike base, whilst rotten yeast gave dimethylamine only. As these compounds result from the action of bacteria on animal tissues, so Brieger showed that the same or analogous compounds were similarly formed in the human subject. In the earlier stages of decomposition, only choline was found. After three days, neuridine appeared in increasing amounts, whilst choline gradually disappeared, being replaced by trimethylamine. After fourteen days, neuridine had also disappeared. Later, there most commonly appeared cadaverine, CHIN2, and putrescine, C,H12N2. With cadaverine is also found a substance of the same composition, called saprine, but differing considerably in its reactions. The bases choline, neuridine, cadaverine, putrescine, and saprine are physiologically indifferent; but after fourteen days' decomposition a new poisonous base, mydaleine, was obtained which seems to be a diamine. In human remains (heart, lung, liver, &c.), maintained at 9 to +5° C. during four months, a new base, mydine, C,HNO, was found, a strongly reducing agent, and a poisonous base, mydatoxine, CH13NO2, also the poisonous methyl-guanidine was isolated. O. Bocklisch, employing Brieger's method, obtained a large number of bases from decomposing fish. The bases so obtained were not poisonous, and attempts to separate the injurious compounds were unsuccessful. The fact that decomposition bacteria induce the formation of numerous basic substances from albuminoid compounds, makes it highly probable that pathogenic bacteria possess similar properties. Thus, Koch, Nicati, and Rietsch have found poisonous ptomaïnes in cholera. In cultivations of typhus bacilla, a strongly basic poison, typhotoxine, C,HNO2, was obtained; and from tetanus cultivations a strong base, tetanine, C13H30N2O4, was obtained. The bases obtained by Brieger are either liquids of definite boiling point, or solid crystalline substances. The salts show the so-called general alkaloïd reactions, so that as a group the ptomaïnes cannot be separated from the alkaloïds. The non-poisonous ptomaïnes readily give rise to poisonous compounds; thus, cadaverine, which has been shown by Ladenburg to be pentamethylenediamine, is converted by rapid distillation of the hydrochloride into the poisonous

piperidine. Whilst the constitution of cadaverine has just been indicated, putrescine is either a dimethylethylendiamine or methylethyl-methylendiamine; which of the two, further investigation must decide. The present methods of isolating the alkaloïds do not yield absolutely certain results, and further extended investigation is required. J. T.

Origin of Ptomaïnes. By C. GRAM (Chem. Centr., 1886, 647). -Although it cannot be denied that a part of the basic products (so-called ptomaïnes) occurring in most putrefying substances is formed by the putrefactive process itself, for instance, the poisonous sepsine found in putrid yeast, it is nevertheless possible that some of these substances may arise simply by reason of the chemical processes involved in the separation of these basic products.

The simple action of heating organic compounds with ammonia salts may give rise to basic products.

The author has for a long time tried in vain to obtain poisonous bases from putrid meat by Maas's method. On treatment with amyl alcohol, an important quantity of these bases was obtained from meat in various conditions of putrefaction, but they were all perfectly inert.

The hydrochloric acid derivatives after heating on a water-bath were also inert, but the lactic acid compounds under similar treatment showed decidedly poisonous properties. Similar observations were made with other bases obtained from putrid yeast free from sepsine.

This transformation of a non-poisonous into a poisonous product by comparatively simple chemical action led the author to study the change of choline into the trimethylvinylammonium base. According to Brieger, the latter poisonous product is a frequent constituent of putrid matter, and arises from the action of putrefactive microphytes on choline.

This same change can be effected by purely chemical means. The lactate of choline when heated, gives rise to a poisonous substance with muscarine-like action. Inasmuch as many researches have shown that choline is widely distributed throughout animal and vegetable organisms, and as it is moreover capable of being converted into a poisonous substance by simple chemical action, the author considers it necessary to conduct researches on ptomaïnes with more caution, and perhaps to regard with mistrust ptomaïnes possessing a muscarinelike action. J. P. L.

Diastase. By O. LOEW (Ber., 20, 58).-A reply to Lintner (this vol., p. 166), in which the author reaffirms the utility of the method of purifying ferments with lead salts, provided due precautions are

taken.

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