Page:The New International Encyclopædia 1st ed. v. 01.djvu/426

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ALKALOIDS.
358
ALKALOIDS.


arrow poison curare, which is made from certain plants, including species of Strychnos.

Daturine, sec Atropine, above.

Emetine, C,„Hj„N05 (or G-^H^^'N.O^ ?) ; melting point, 62° — 65° C.; soluble in alcohol, ether, and chloroform ; gives with a solution of sodium moljbdate in strong sulphuric acid a brown coloration which turns blue on addition of hy- drochloric acid. It is the active principle of ipecac, the root of Cephaelis ipecamunha. Eserine, or Physostigmine, CuHj^NjO, ; melt- ing point, 40° — 45° C; soluble in alcohol, ether, and chloroform; bleaching powder colors its solution red, but the color disappears again on addition of an excess of bleaching powder. It is the active principle of Calabar bean, the seed of Physostif/ma venenosum Balfour.

Hyoscyamine, CnHjaNOj; melting point, 108.5° C. ; soluble in water, alcohol, ether, and chloro- form; gives a purple color with strong nitric acid. By the action of caustic alkalies it is readily transformed into the alkaloid atropine (see above). Hyoscyamine is found in many plants of the natural order Solanacew ; e.g., in henbane, the leaves and flowering tops of Hyos- cynmus niger Linné, and in the leaves of Atropa belladonna Linné.

Morphine, CnHuNO,; melting point, 230° C; It may be extracted from alkaline solutions by means of chloroform. With strong nitric acid it gives a blood-red coloration that gi-adually turns yellow. It is one of the constituents of opium.

Muscarine, CoHisNOa; a liquid soluble in water and in alcohol; insohible in ether and chloroform. It is found in the fly fungus, Amanita muscaria.

Narceine, C^HkNOs; melting point, 145.2° C. ; sparingly soluble in the ordinary solvents. A solution of sodium molybdate in strong sul- phuric acid gives a gi'een coloration that turns dark-red. It is one of the constituents of opium, and resembles morphine in its physiological ac- tion.

Narcotine, C2;H,,N0, ; melting point, 176°; soluble in chloroform, less soluble in hot alco- hol and ether. Its solutions are l^vo-rotatory, but when acidified turn the plane of polarized light to the right. It is one of the constituents of opium.

Nicotine, Ci„Hi,N,; boiling point, 241° C. ; soluble in water, alcohol, and ether; its smell and taste are like those of tobacco. With hydro- chloric acid it gives a violet coloration that turns orange on addition of nitric acid; with iodine solutions it gives a yellow precipitate. It is the active principle of tobacco, the dried leaves of Nicotiana tabacum; tobacco smoke, however, contains no nicotine.

Papaverine, C.-oHniXO^; melting point, 147° C. ; soluble in hot alcohol and in chloroform; gives a violet coloration with .strong sulphuric acid. It is found in opium.

Physostigmine, see Eserine, above.

Piloearpine, C„H„,NjO.; a semifluid alkaloid soluble in alcohol, ether, and chloroform ; gives a green coloration with strong sulphuric acid and potassium bi-chromate. It is one of the active principles of pilocarpus, or jaborandi, the leaflets of Pilocarpus selloumts Engler, or of Pilocarpus jaborandi Holmes.

Piperidine, C..H„N; a liquid alkaloid produced by the decomposition of piperine, a substance found in pepper.

Piperine, CuHioNO^; melting point, 128° C; soluble in hot water and in chloroform; with strong sulphuric acid it gives a j-ellow color that changes to brown, then to a greenish brown. It is found in plants of the natural order Piper- aeece, and is one of the chief constituents of ordinary black pepper.

Quinidine, CioHo.NjO,; melting point, 168° C; soluble in chloroform^ less so in alcohol and ether; sparingly soluble in water; its solution turns the plane of polarized light to the right. It is found in cinchona bark.

Quinine, C'mHoiN.O; -f SH-O ; melts in its water of crystallization at 57° C, loses its water at 100°, then melts again at 177° C. ; soluble in alcohol, ether and chloroform, sparingly soluble in water; its solutions turn the plane of polar- ized light to the left. It is found in cinchona bark.

Solanine, C^H^NO,,; melting point, 235° C; it may be extracted from its alkaline solutions by means of chloroform ; with strong sulphuric acid it gives an orange coloration that turns a brownish red. It is found in bittersweet (woody nightshade), the young branches of Solanum dulcamara Linne.

Strychnine. CiiH.^NjO, ; melting point, about 264° C. ; soluble in chloroform and in hot alco- hol; sparingly soluble in water and in ether. It gives a pretty display of colors with strong sul- phuric acid and a grain of potassium bi-chro- mate. It is found in plants of the natural order Loganiacew, and is usually obtained from nux vomica.

Thebaine, or Paramorphine, CmHjiNOj; melt- ing point, 193° C. ; soluble in alcohol and chlo- roform; gives, with strong sulphuric acid, a dark-red coloration which turns yellow. It is found in opium.

Theine, see Caffeine, above.

Theobromine, CjHsX^O;; sublimes without melting at 290° C. ; sparingly soluble in the or- dinary solvents; may be extracted from an alka- line solution by means of chloroform. On eva- poration with chlorine-water a brown residue is obtained that turns purple if a little ammonia is added. It is found in cacao beans.

Veratrine, C3„H„N„0,, ; a mixture of two iso- meric alkaloids; melting point. 155° C. ; soluble in alcohol, ether, and chloroform ; gives a red coloration if heated with strong sulpliuric or with fuming hydrochloric acid. It is found in the seed of Asagrwa o/licinalis Lindley.

The extraction of an alkaloid from the plant in which it occurs is often a matter of considerable difficulty. The volatile alkaloids may be obtained by distilling the plant or vegetable product with water and lime (or caustic soda); the liquid distilling over is neutralized with sulphuric acid and evaporated to dryness; the sulphate of the alkaloid may then be dissolved out of the residue by means of a mixture of alcohol and ether. To extract a non-volatile alkaloid, the plant is macerated and treated with a dilute solution of some acid in ordinary alcohol; the solution thus obtained is rendered alkaline by the addition of soda, and the alkaloid set free is either directly obtained in the form of a precipitate, or else may be extracted from the alkaline solution by means of ether, chloroform, or some other solvent that docs not mix with water. Such processes, however, usually yield not one single, but mixtures of two or more alkaloids, and those contaminated with large