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specific rotation of piperidine bases (this vol., p. 164), the author finds for a-pipecoline [a] = 21·74°, and for a-ethylpiperidine [a]D 6-75°. a-Isopropylpiperidine and B-pipecoline do not yield optically active bases by conversion into dextrotartrates. From the motherliquor of the a-pipecoline hydrogen tartrate the lavorotatory base was obtained; but this, even after conversion into the hydrochloride and treatment with cadmium iodide to remove any accompanying dextrorotatory base, gave only a specific rotation of -19°, and probably contained either the dextrorotatory or the inactive base as impurity which could not be separated. Experiments show that the inactive piperidine bases are compounds and not mixtures of the optically active modifications; and therefore it has been possible to effect a decomposition into two optically active salts only in those cases where the temperature employed in the crystallisation lay above or below the transition temperature of the inactive hydrogen dextrotartrate (comp. Abstr., 1886, 968).

The unexpectedly low specific rotation of the dextrorotatory a-ethylpiperidine renders it probable that the specimen employed was not W. P. W.

pure.

Alkaloïds of the Berberideæ. By O. HESSE (Ber., 19, 31903191). The author has re-investigated the alkaloïds in the root of Berberis vulgaris. He believes that there are therein at least four alkaloïds besides berberine, and describes especially oxyacanthine (Wacker, Chem. Centr., 1861, 321), and a new alkaloid he has obtained from the mother-liquors of oxyacanthine, and which he names berbamine.

= +131·6°

He finds the true formula of oxyacanthine to be C8H19NO, and not C19H21NO3, as he has previously given. When crystallised from water and dried at 100°, this alkaloïd melts at 138-150°, but when crystallised from alcohol or ether, it forms needles melting at 208-214°. It is easily soluble in chloroform, and then gives [a]D (p = 4, t = 15°). In light petroleum and alkalis, it is only slightly soluble, and ether extracts it completely from the alkaline solutions. The hydrochloride, C1H19NO3,HCI + 2H2O, forms small colourless needles which in aqueous solutions give [a]D = +163·6' (p = 2, t = 15°). The platinochloride is a yellow, flocculent precipitate. The nitrate and sulphate are both crystalline. When heated with potash and a little water, the base melts to a brown mass which floats on the surface of the fused potash. This brown mass is the potassium compound of B-oxyacanthine. This conversion into a ẞ-modification also takes place very readily, even at ordinary temperatures, when the alkaloïd is acted on by alkalis or barium hydroxide in the presence of alcohol. Ether now no longer extracts the alkaloïd from the alkaline solution. Hydrochloric acid precipitates B-oxyacanthine, which is soluble both in alkalis and in excess of acid. If, however, the alkaline solution of the B-compound is supersaturated with hydrochloric acid, a-oxyacanthine hydrochloride crystallises out. The author believes the B-modification is due to the alkaloid taking up an additional molecule of water. Oxyacanthine very closely resembles narcotine in properties.

Berbamine crystallises in small scales of the composition CH,NO, + 2H2O. It is easily soluble in ether. When anhydrous, it melts at 156°. The hydrochloride crystallises in scales, the nitrate in needles; the platinochloride forms a yellow crystalline precipitate.

25

L. T. T.

Colchicine. By S. ZEISEL (Monatsh. Chem., 7, 557-597).— Previous observations on the composition and properties of colchicine have, for the most part, been very discordant; in this paper, a long summary is given. The principal results obtained by the author are as follows: the composition of colchicine is expressed by the formula CH2NO; it combines with chloroform to form a crystalline compound, C22H25NO, 2CHCl3, readily decomposed by water into its components. Colchicine is slightly basic, but its salts, with the exception of an aurochloride, C22H25NO6, HAuCl, cannot be obtained from their aqueous solutions. Colchiceïne, formed from colchicine, when heated with a trace of hydrochloric or sulphuric acid, has the composition 2C2H23NO6, H2O. As the difference between the two compounds is one CH, or methylene group, and as methyl alcohol is produced in the decomposition, it follows that colchiceïne is a demethylated colchicine.

Colchiceïne possesses at once the properties of a base, as evidenced by the formation of an aurochloride, C2H3NO, HAuCl,, and also those of a monobasic acid, or more probably of a phenol, as shown by the formation of a copper derivative (C2H2NO6) Cu, and by the readiness with which it dissolves in alkalis. As colchicine has no acidic properties, it is probably a methoxy-derivative of a compound, of which colchiceïne is the corresponding hydroxy-derivative.

It is suggested that the molecular formula of each of the above substances is the double of that given; owing to the complex composition of the substances, the number of hydrogen-atoms is given with a certain reserve.

V. H. V.

Ecgonine. By C. E. MERCK (Ber., 19, 3002-3003).-The author has repeated an experiment made by Calmels and Gossin (Abstr., 1885, 912), and finds that ecgonine when distilled with almost dry barium hydroxide yields methylamine and not ethylamine as one of the products; this corresponds with the behaviour of tropine under like conditions. When ecgonine hydrochloride is heated with an qual weight of phosphorus pentachloride and 10 parts of chloroform at 100° for 10 hours, a base is obtained which yields a well crystallised aurochloride, CH, NO,HAuCl,, corresponding with ecgonine less the elements of 1 mol. H2O. The base has not yet been obtained in the pure state. W. P. W.

A New Ptomaïne producing Tetanus. By L. BRIEGER (Ber., 19, 3119-3121). The author has already described an alkaloïd, tetanine, obtained in the cultivation of Rosenbach's microbe. The beef extract in which the microbe had been cultivated for four to six weeks, was acidified with hydrochloric acid, boiled, and filtered; the filtrate evaporated and treated with lead acetate and alcohol, filtered, and the lead removed as far as possible as chloride, and finally as

sulphide. The strongly alkaline filtrate was distilled with steam, acidified with hydrochloric acid, evaporated to dryness, and treated with alcohol to remove ammonium chloride. After removing the alcohol, the new base was separated as its aurochloride.

The free base, C,H,N, is volatile, boils about 100°, but was not obtained free from water. The hydrochloride is crystalline, melts at 205°, and is very readily soluble in water and absolute alcohol. The aurochloride, CH1N,HAuCl, crystallises in plates, and melts at 130°. The platinochloride, (CHN)2,H,PtCl, crystallises in plates, is decomposed at 240°, and is sparingly soluble in water. The picrate crystallises in readily soluble needles. The base gives a yellow precipitate with phosphomolybdic acid, a white precipitate with phosphotungstic acid, and a red crystalline precipitate with potassium bismuth iodide. Injected hypodermically in a comparatively large dose, it produces the symptoms of tetanus. A. J. G.

Albumoses. By R. NEUMEISTER (Zeit. Biol., 23, 381-401).-The question investigated in this research was whether or not each albumose was converted into isomerides belonging to the anti- and hemi-groups of digestion products.

The method previously described by Kühne and Chittenden of separating proto- from deutero-albumose is not a satisfactory one. Hetero-albumose is easily separated by its being precipitated when the salts are dialysed out from a mixture of the albumoses. It can also be separated from the mixture by saturating it with sodium chloride; part of the proto-albumose and the whole of the deutero-albumose remain in solution. In the precipitate, hetero-albumose can be separated by dialysis as before. By acidifying the filtrate, which contains the dentero-albumose and part of the proto-albumose, the protoalbumose and about half the deutero-albumose are precipitated; this is filtered off; the deutero-albumose remaining in solution is not mixed with any other albumose; the sodium chloride is dialysed off, the fluid is saturated with ammonium sulphate, and thus the peptone alone is left in solution; the precipitate of deutero-albumose is redissolved and obtained free from ammonium sulphate by dialysis, and finally precipitated by alcohol. It gives no precipitate with copper sulphate; previous statements that such a precipitate occurs were due to its admixture with proto-albumose.

On prolonged heating of proto-albumose with 5 per cent. sulphuric acid, deutero-albumose is formed. Hetero-albumose yields the same substance, and also anti-albumid. The same result is obtained on peptic digestion, and also on tryptic digestion, more rapidly in the latter case than the former. The formation of the so-called globulinlike substance does not occur in tryptic digestion.

No deutero-albumose is formed directly from fibrin; but protoand hetero-albumose are intermediate products in its formation, both by acids and by ferments.

Anti-albumid yields deutero-albumose also, and seems to be largely a bye-product of the formation of hetero-albumose. The deuteroalbumose obtained is an anti-product yielding only anti-peptone; much insoluble anti-albumid is left after prolonged digestion, which will

VOL. LII.

yield no more albumose. This insoluble substance swells with sodium hydroxide; it is turned yellow by nitric acid, and orange on the subsequent addition of ammonia; in its solubilities it much resembles keratin.

The deutero-albumose formed from proto- and hetero-albumose is called ampho-deutero-albumose, as it is subsequently converted into amphopeptone (that is, hemi- and anti-peptone); the anti-products from proto-albumose are, however, exceedingly small in quantity, and the author suspects that his method of preparing proto-albumose does not give him that substance quite free from traces of hetero-albumose; and that perfectly pure proto-albumose will be found to be a pure hemi-albumose. The changes in the digestion of albumin are represented in the following schemes.

[blocks in formation]

Amphodeutero-albumose. Amphodeutero-albumose. Antideutero-albumose.

Amphopeptone.

Amphopeptone.

Antipeptone.

W. D. H.

Vitelloses. By R. NEUMEISTER (Zeit. Biol., 23, 402-411).— Following on the lines of Kühne and Chittenden, the products of the digestion of vitellin have been subjected to analysis. The variety of the proteïd employed was plant vitellin (phytovitellin), prepared from pumpkin seed.

Coagulated vitellin was found to be the best to employ; in peptic digestion, syntonin was formed as one product. This resembled ordinary acid albumin, except that it was insoluble in strong nitric acid, and gave the biuret reaction, not the ordinary purple colour. A substance, antivitellid, corresponding with anti-albumid, was also formed, but no coagulable substance like that obtained in the peptic digestion of globulin.

The ultimate products of digestion are peptones; vitellose is the name given to the intermediate products: proto-, hetero-, deuteroand dysvitellose, which correspond with the albumoses with similar prefixes. These may be separated from one another and from peptones as the albumoses are.

Protovitellose becomes deuterovitellose on further peptic digestion: when subjected to the action of the tryptic ferment, a trace of antivitellid

is formed; the end products are antipeptone, tyrosine, leucine, and the substance which becomes violet with bromine.

Heterovitellose and dysvitellose, derived from it, do not differ in their properties from the analogous albumoses; under tryptic digestion, much antivitellid is formed, the end product being antideuterovitellose. Under prolonged peptic digestion, amphodeuterovitellose is formed.

The anti- and ampho-varieties of deuterovitellose correspond with the similarly named albumoses. W. D. H.

Physiological Chemistry.

Gases of Parotid Saliva. By R. KULZ (Zeit. Biol., 23, 321328).-Observations on the gases of human saliva have not been previously made. The saliva was obtained by means of a gum elastic canula (which was found to be better than the metal one at first used) inserted into Stenson's duct; the saliva was collected over mercury to obviate the danger of absorption of atmospheric air.

As the mean of 11 analyses, the total quantity in volume from 100 c.c. of saliva was 7 c.c. of gas, of which 1 c.c. was oxygen, 2.5 nitrogen, and 3-5 c.c. carbonic anhydride. By the addition of phosphoric acid, a large amount (40-60 per cent.) of carbonic acid contained in the saliva as carbonates was obtained. The amount of oxygen and nitrogen in the saliva exceeds that in the blood-serum.

With regard to the carbonic anhydride present, and the alkalinity of the secretion which is due to the carbonates, it is found that food in the stomach does not alter the reaction of the saliva as it does that of the urine. After an abundant secretion of gastric juice, many observers have noted, and these experiments confirm their results, that the urine becomes less acid or even alkaline. That there is no such effect on the saliva is shown both by the estimation of the carbonic acid and by titration. W. D. H.

Free Hydrochloric Acid of the Gastric Juice. By H. A. LANDWEHR (Chem. Centr., 1886, 484).-The author has previously shown, in conjunction with Fick, that the action of this acid on diastase is inverted in the presence of peptones, in the sense that its activity is increased rather than suspended; the cause probably lying in its combination with amido-acid groups of the peptones. Calm has recently shown (Deut. Arch. f. klin. Med., 23) that in certain pathological conditions the gastric juice has the reactions rather of an organic acid than of dilute hydrochloric acid.

It is well known that lactic acid decomposes sodium chloride. That this taken place in cold dilute solution is readily seen by comparative observations of the acidity (methyl-violet being used as indicator) of a lactic acid solution before and after addition of sodium chloride.

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