Bromine Derivatives of Nicotine. R. Laiblin. (Ber. der deutsch. chem. Ges., xiii., 1212-1214. From Journ. Chem. Soc.) By the action of bromine and water on nicotine in sealed tubes at 120-150°, the author has obtained a crystalline compound similar to that obtained by Cahours and Etard, which is probably C10 H12 Br2 N2+ H Br. On treatment with potash it yields nicotine.

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Bromonicotine, C10 H12 N2 Br2.-For the preparation of this compound the author recommends the following method, instead of Huber's (Annalen, cxxxi., 257), which does not yield very good results. To 50 grams of bromine and 30 grams of water is added a solution of 16 grams of nicotine in 20 grams of water in small quantities at a time, the temperature not being allowed to rise above 50-60°. The whole is warmed on a water-bath until the oil so formed is dissolved, and then 60-70 grams of water are added; on cooling a crystalline body separates out, probably the compound C10 H12 Br2 No. 2 H Br. This is decomposed by aqueous ammonia, and yields bromonicotine. The author is at present engaged in the study of the oxidation-products of this body.

Conine, and some of its Salts. Prof. A. W. Hofmann. (Ber. der deutsch. chem. Ges., xiv., 705.) The results of careful analyses of this alkaloid and of its hydrochlorate and hydrobromate have convinced the author that the formula, Cg H15 N, generally accepted for this base, ought to be replaced by Cg H17 N. This corrected formula disposes of the supposed identity with conine of several artificial products of the formula Cg H15 N.

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The hydrochlorate, Cg H17 N. H Cl, is obtained as a brilliant white crystalline mass by dissolving conine in anhydrous ether and treating the solution with dry hydrochloric acid gas. It is very soluble in water and alcohol, but insoluble in ether, and can be heated to 100° C. without suffering decomposition.

The hydrobromate, Cg H17 N. H Br, is formed under the same conditions as the hydrochlorate, if H Br be used in the place of HCl. It may also be readily prepared by adding bromine drop by drop to a solution of conine in anhydrous ether, as long as the bromine continues to be decolorized. The salt thus separates as a crystalline mass, while a substitution product of conine remains dissolved in the ether. In its behaviour towards solvents and heat

it corresponds to the hydrochlorate.

The Alkaloid from Pituri. Prof. Liversidge. (Abstract of a paper read before the Royal Society of New South Wales, November 3rd, 1880. Pharm. Journ., 3rd series, xi., 815-818.) In the preparation of the alkaloid by the author the pituri was extracted with

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boiling water slightly acidified with sulphuric acid, the liquid concentrated by evaporation and distilled with an excess of caustic soda, the alkaline distillate neutralized by hydrochloric acid, and evaporated over a water-bath until reduced to a small bulk; the yellowish residue was once more distilled with caustic soda, the distillate neutralized with hydrochloric acid, and again concentrated. It was now nearly colourless, caustic soda was again added, and the liquid shaken up with ether. The ether was next removed by distillation at as low a temperature as possible in a current of hydrogen, the heat meanwhile being raised gradually until it reached 140° C., a bath of sulphuric acid being used for this purpose. It was allowed to remain at this temperature for about six hours; the bath was then removed, and the distillation continued at a still higher temperature over a naked flame, the current of hydrogen being still maintained, until all the alkaloid, with the exception of a very small quantity, which had become charred, had passed over in a clear and colourless condition. During the distillation the thermometer indicated a temperature between 243° and 244° C.

Sixty grams of the substance gave 622 gram of the alkaloid, or 1.037 per cent. In this case the alkaloid was not allowed to boil, but was maintained at a temperature of 140° C. in a current of hydrogen for several hours, to remove water and traces of ammonia. In a second experiment 500 grams of the pituri gave 12:34 grams of alkaloid, or 2:47 per cent., when distilled in a current of hydrogen. The pituri did not contain any non-volatile alkaloid.

The alkaloid when freshly prepared is clear and colourless, but with access of air rapidly becomes yellow, and finally brown, especially when exposed to sunlight. In a sealed tube one specimen remained unchanged during eight months. It is soluble in all proportions of water, alcohol, and ether, yielding colourless solutions. On paper it produces a greasy stain, which disappears after a time. It is just a little heavier than water, a little drop of it sinking slowly to the bottom of a vessel of distilled water.

When freshly prepared its smell is very like that of nicotine; afterwards, when darkened in colour and thickened in consistency, the odour is more like that of pyridine. It is volatile at ordinary temperatures, its vapour forming a dense fog with hydrochloric acid. Its vapour irritates the mucous membranes very much, and when working with it induced violent headaches. The taste is acrid and pungent, and very persistent.

The alkaloid neutralizes acids completely; but the neutral solutions of acetate, sulphate, and hydrochloride all become acid on

evaporation from the loss of alkaloid. Oxalic acid is the only acid which yields a crystalline salt; but this is more or less mixed with free acid, from the loss of alkaloid by volatilization, an acid salt mixed with free oxalic acid being left. The acetate, sulphate, and hydrochloride, when kept over strong sulphuric acid, dry up into hard, brittle, transparent, varnish-like substances, without the slightest trace of crystallization, even after standing for months. All these compounds are very hygroscopic, especially the sulphate, and are very readily soluble in alcohol.

Neither concentrated hydrochloric acid nor nitric acid changes the colour of the alkaloid in the cold, but when warmed, hydrochloric acid imparts a slightly reddish colour, and nitric acid turns it yellow. Concentrated sulphuric acid turns it brown after some time, immediately when warmed.

Platinic chloride does not precipitate an aqueous solution of the alkaloid (1.100 aq.) so long as the alkaloid is in excess, but when the solution has become neutralized the addition of another drop of platinic chloride throws down a slight yellowish flocculent precipitate, which dissolves on heating, but does not reappear on cooling; if a larger quantity of the platinic chloride be added, the precipitate still dissolves on the application of heat, but on cooling reappears in a crystalline condition.

In a solution of 1 part of the hydrochloride of the alkaloid to 50 of water, a precipitate similar to the above is thrown down, and if heated, a part re-dissolves, the undissolved portion turns to an orange-yellow colour and becomes crystalline-the dissolved salt also crystallizes only on cooling. Under the microscope the crystals appear to have the form of the octahedron, or combinations of that with other forms belonging to the cubical system. More dilute solutions of the hydrochloride are not precipitated by platinic chloride.

In an aqueous solution of 1 part of the alkaloid to 100 of water,Mercuric chloride throws down a white cheesy precipitate insoluble in excess of the precipitant.

Copper sulphate a light green precipitate insoluble in an excess of the alkaloid.

A few drops of gold chloride give a reddish white precipitate, which disappears on shaking; a larger quantity gives a persistent flocculent reddish white precipitate.

Tannic acid gives a greyish white precipitate, easily soluble in hydrochloric acid.

The double iodide of mercury and potassium gives a heavy white crystalline precipitate.

The alkaloid behaves very like nicotine with picric, phosphomolybdic, and metatungstic acids; the addition of picric acid throws down a yellow precipitate soluble in hydrochloric acid.

Phosphomolybdic acid forms a yellowish white amorphous precipitate, insoluble in cold dilute hydrochloric acid, easily and completely dissolved on warming. The precipitate with nicotine is a dirty yellowish white, amorphous, insoluble in cold dilute hydrochloric acid, soluble when warmed, but apparently not so readily as is the precipitate from the pituri alkaloid, some white flakes being left undissolved.

Metatungstate of sodium forms, with both piturine and nicotine, a white amorphous precipitate, soluble only in much dilute hydrochloric acid when warmed.

When iodine dissolved in ether is added to an ethereal solution of the alkaloid, the fluid becomes brownish red and turbid; after a short time yellowish red needles are deposited, the mother-liquor being yellow; these crystals are easily soluble in alcohol, yielding a brownish red solution; when the alcoholic solution is evaporated at the ordinary temperature, indistinct needles and oily drops are left behind.

When this alcoholic solution is treated with caustic soda in the cold, a smell similar to that of iodoform is emitted, not that of the alkaloid; from the nicotine compound nicotine is liberated, according to Wertheim (Watt's " Dictionary of Chemistry," iv., p. 47). The iodine compound of pituri melts at about 110° C., that of nicotine at 100° C.

From conine piturine is distinguished by its aqueous solution not becoming turbid on heating nor by the addition of chlorine water. It differs from aniline by not being coloured by chlorinated lime; it differs from picoline in specific gravity (picoline being only 9613 at 0° C); from pyridine by its reaction with copper sulphate, the precipitate Cu (OH), produced by pyridine with copper sulphate redissolves in an excess of the precipitant; and it appears to be distinguished from nicotine by its reactions with platinic chloride, gold chloride, and iodine and mercuric chloride, also by Palm's test. According to the latter, nicotine, when gently warmed with a little hydrochloric acid of 1.12 sp. gr., turns violet, and on the addition of a little strong nitric acid the colour changes to a deep orange. Piturine, thus treated, does not change colour at all, but when more heat is applied it becomes yellow.

These results completely disprove M. Petit's statement that the alkaloid of pituri is identical with nicotine (Year-Book of Pharmacy, 1879, p. 98).

The number obtained by the author in eight combustions of piturine lead to the formula C, H, N. From the results of analysis of the mercuric chloride double salt, however, he feels inclined to double that formula, or C12 H16 N2, as probably the more correct representation of the composition of the alkaloid.

Behaviour of Berberine towards Thymol. J. U. Lloyd. (New Remedies, 1881, 195.) The author observed that berberine, prepared from Hydrastis canadensis, when mixed with an equal weight of thymol, yielded a viscid liquid, though both the thymol and berberine were used in the form of dry powders. The berberine had been exposed to warm air in a drying closet, whereby most of its water of crystallization was expelled. The cause of this liquefaction remains to be investigated.

Estimation of Theine in Tea. M. Patrouillard. (Correspondenz Blatt des Ver. Analyt. Chem., 1880, No. 14.) 15 grams of tea are repeatedly extracted with boiling water until exhausted. The filtered decoctions are evaporated to the consistence of an extract, then mixed with 2 grams of calcined magnesia and 5 grams of powdered glass, and further evaporated to perfect dryness. The finely pulverized residue is treated with 60 c.c. of ether four successive times, after which the united ethereal solutions are allowed to evaporate. The theine thus left is redissolved in a little chloroform, and the solution allowed to evaporate in a weighed dish. Care must be taken not to use too little ether, since theine is only slightly soluble therein.

Caffeine and Theobromine. MM. Malay and Hinteregger. (Monatshefte für Chemie, ii., 87 and 126.) The authors have studied some oxidation compounds of these two bases with the object of throwing further light on their relation to each other. By oxidation with chromic acid, caffeine yielded dimethylparabanic acid, CH N2 Og, while theobromine under the same treatment was found to yield methylparabanic acid, C4 HN, Og, the difference (CH2) between the two products being the same as that between the two alkaloids themselves.

Caffeine and Caffeidine. Dr. E. Schmidt. (Ber. der deutsch. chem. Ges., 1881, 813-817.) The author describes some unsuccessful attempts to convert caffeine, Cg H10 N4 Og, into theobromine, CH, NO2, by withdrawing methyl groups by means of hydrochloric acid. Similar attempts to convert caffeine into xanthine or decomposition products thereof likewise proved unsuccessful.

Definite salts of caffeine could only be produced by the direct action of acids upon the base in concentrated solutions. The salts