562 22 2 2 BRUCIA. acid salt with strychnia; the crystals of the neutral sulphate [(Є, H ̧Ñ‚Ð ̧),H2SO, 7 H2O] are square prisms. Solutions of the salts of strychnia yield a precipitate with infusion of galls. If a slight excess of tartaric acid be added to the solution of a salt of strychnia, and then one of hydro-sodic or hydro-potassic carbonate, the strychnia is gradually deposited in crystals. A solution. which does not contain less than its weight of the base gives, on the addition of a strong solution of potassic sulphocyanide, tufts of crystals, after the lapse of a few minutes. A minute quantity of strychnia with concentrated sulphuric acid, and a fragment of peroxide of lead, or what is still better, of potassic dichromate, gives a beautiful violet tint, which gradually fades into a pale rose colour; other oxidizing agents produce a similar effect. With solution of auric chloride, salts of strychnia give a bright blue colour. The presence of strychnia may be detected. in very minute quantities in complicated organic liquids, by rendering them alkaline with potash, and agitating thoroughly with a few drachms of chloroform; the chloroform dissolves the strychnia, and leaves it in the solid form on evaporation; from this residue it may be extracted by dilute hydrochloric acid; and it may afterwards be submitted to the usual tests. (1404) Brucia (Є23H26N24, 4 H20=394+72; Regnault) is more soluble in water, and in strong alcohol, than strychnia. This alkali is contained in nux vomica in larger quantity than strychnia. It may also be readily obtained from the false angustura bark (Brucea antidysenterica), which does not appear to contain any strychnia, but furnishes brucia more abundantly than the beans of the nur vomica. Brucia crystallizes in colourless, transparent, oblique rhombic prisms, which are insoluble in ether. This base melts readily on the application of heat, and loses its water of crystallization. It is less active as a poison than strychnia. Its salts have a bitter taste, and may be distinguished from those of strychnia, after they have been mixed with tartaric acid, by not yielding any precipitate on the addition of hydrosodic carbonate. This base is further distinguished from strychnia by the bright scarlet colour gradually passing into yellow, which brucia or any of its salts gives with nitric acid; if a little stannous chloride be added, a beautiful violet colour is produced. The action of nitric acid upon brucia is attended with the production of definite results, from which it appears to be probable that methyl enters into the composition of this base. When the concentrated acid is poured upon brucia, the mixture assumes a deep red colour, becomes hot, and emits a colourless gas, which OTHER LESS KNOWN BASES. 563 has the peculiar smell of apples, and a portion of which is soluble in water and in alcohol. This gas consists of a mixture of nitrite of methyl with nitric oxide and carbonic anhydride, the anhydride being the secondary result of the decomposition of oxalic acid, which is found in the liquid, accompanied by a new substance termed cacotheline; this last-named body is a nitro-substitutioncompound, of feebly basic properties. Strecker represents the action of nitric acid upon brucia by the following equation : Brucia Nitric acid. Methyl nitrite. Oxalic acid. Cacotheline. : €23H26N904 + 5 HNO3 = &H2NO2 + H ̧¤‚¤ ̧ + ¤H2(NO2)2N2O5 + 2 (NO) + 2 H2e. A further proof of the presence of methyl in brucia is found in the fact, that when this base is distilled with dilute sulphuric acid and black oxide of manganese, or with potassic chromate and sulphuric acid, formic and carbonic acids are produced, and an inflammable liquid passes over, burning with a blue flame, and presenting the properties of wood spirit. Igasuria. This name covered in nux vomica. strychnia or brucia.* has been given to a third alkali disIt is more soluble in water than either The Urari or woorara poison of South America appears to be obtained from a plant of the strychnos tribe; it acts as a fatal poison if introduced into the blood by a wound, but it may be swallowed with impunity. (e) Other less known Bases. (1405) The bulbs of the Colchicum autumnale and the roots and seeds of different species of Veratrum contain several alkaloids, * Schutzenberger (Ann. de Chimie, III. liv. 65) states that he found in the base reputed to be igasuria, no fewer than nine closely related bases, which could be separated by fractional crystallization from boiling water. They are all intensely bitter, and are poisonous, resembling strychnia in their effects. They all are reddened by nitric acid; he assigns to them the following formula: N 204, 3 H0 or 4 H2O? soluble; (9) HNO 3 HO sparingly soluble; 21 (h) H26N26, 2 H2O moderately soluble; These results afford an illustration of the vast number of bases which may be produced by the actions of a single plant; they show the difficulty of investiga tions of this kind, and may serve to explain the discordant analytical results sometimes arrived at by chemists of tried ability. 32 52 2 the most important of which, veratria, has been employed medicinally. Veratria (Є,,H,,N,,; Merck) occurs principally in combination with gallic acid; it is an extremely acrid and violent poison, producing dangerous fits of sneezing if it come in contact, even in minute quantity, with the mucous membrane of the nose. It acts as a valuable sedative in some cases of neuralgia, if applied in the form of ointment to the surface of the body. Veratria is almost insoluble in water and in alkaline solutions; alcohol dissolves it freely, and deposits it by spontaneous evaporation, in long delicate needles. Ether dissolves it with difficulty; fuming sulphuric acid colours it yellow, then blood-red, and lastly, violet. Nitric acid strikes with it a red which after a time becomes yellow. Three other poisonous bases, sabadillia, colchinia, and jervia, are found, along with veratria, in the Veratrum album, or white hellebore. Jervia (EHNO3, 2 H2O? Gerhardt, from Will's analysis) is white, crystalline, and fusible. 47 2 Aconitina (E30H4NO,? Planta) is another intensely poisonous alkaloid, which is employed medicinally, but the composition of which is uncertain; it is obtained from various species of monkshood or aconite. It crystallizes with difficulty, and is more soluble in water than most of these bases; it is dissolved easily by alcohol and ether. These solutions have a powerfully alkaline reaction; and the base forms perfectly neutral salts, which when moistened with concentrated sulphuric acid acquire a colour which at first is yellowish, and then becomes of a dirty violet red. 17 43 701 16' To Many of the Solanaceae and Umbelliferæ contain alkaloids. The henbane (Hyoscyamus niger) and both the common and the deadly nightshade (Solanum dulcamara, and Atropa belladonna) owe their poisonous qualities to compounds of this kind. Solania Zwenger assigns the formula €,HNO, Atropia [EHNO3; Planta; Fusing pt. 194° (90° C.)] crystallizes in colourless silky needles, which are freely soluble in alcohol and in chloroform, but less so in ether. The crystals fuse at 1940, and undergo sublimation and partial decomposition at 284°. Solutions of atropia are speedily altered by evaporation when exposed to the atmosphere. Atropia is present in all parts of the belladonna, but is commonly extracted from the root. It appears to be identical with daturia, the active principle contained in the seeds of the Datura stramonium. The salts of atropia are bitter, acrid, and highly poisonous, producing a remarkable dilatation of the pupil of the eye. In addition to these bases two others may be mentioned, viz., harmaline and harmine, which are found, probably combined with HARMALINE-EMETIA-CAFFEINE OR THEINE. 565 phosphoric acid, in the husk of the seeds of the Peganum harmala, or Syrian rue, a plant extensively grown in the steppes of Southern Russia. The seeds of this plant are used in dyeing silk, to which they impart various shades of pink, rose, or red. The seeds also possess narcotic properties, but the active principle to which this effect is due has not been investigated. Hurmaline (HN) when pure crystallizes in colourless prisms, but they generally retain a brownish yellow tint, and tinge the saliva yellow. It has a bitter, astringent, acrid taste; it is freely soluble in alcohol, but sparingly so in water and in ether. It is fusible and volatile; with acids it forms yellow, very soluble, crystallizable salts. Oxidizing agents transform it into a red colouring matter which combines with acids, forming salts which constitute the basis of the harmala red of commerce. Harmaline contains two atoms more of hydrogen than harmine (Є1H12N2→; Fritzsche), into which it may be converted by oxidation; harmine crystallizes in long delicate prisms; it forms colourless salts which are quite neutral. 12 2 Emetia, the active principle of ipecacuanha, also possesses the properties of a feeble base: it is nearly insoluble in water and in ether, but is readily soluble in alcohol and in dilute acids; chloroform also dissolves it with facility. It is a powerful poison, and acts as a violent emetic in doses of one-sixteenth of a grain or less. It fuses readily, and is accompanied in the ipecacuanha root by a large proportion of oily matter, which emits a feeble odour of tobacco when heated. The base is easily obtained by treating the alcoholic extract of the root with dilute sulphuric acid, filtering from the oily matter, and after slightly supersaturating the solution with ammonia, agitating the turbid liquid with chloroform. On evaporating the chloroform, the emetia is left as a yellowish resinous-looking mass. It may be purified by conversion into a salt, and digesting its solution with a small quantity of animal charcoal; on adding an alkali to the filtered liquid the emetia is precipitated. The salts of emetia do not readily crystallize. (f) Alkaloids of Coffee, Tea, and Chocolate. 8 4 2 (1406) CAFFEINE, or THEINE (H1N ̧,,H ̧→ = 194+18; (EH10) NᎾ,H Ꮎ Fusing pt. 454° (234° C.); Strecker. This substance occurs in tea, in coffee, and in maté, a shrub used by the natives of Paraguay and a large number of the inhabitants of South America, for making an infusion which they substitute for tea, as well as in the kola-nut used by the natives of Central Africa. It is also contained to the extent of 5 per cent. (Stenhouse) in guarana, an astringent species of chocolate prepared from the fruit of the Paullinia sorbilis. Tea appears to contain from 2 to 4 per cent. of caffeine (Péligot), but the quantity of it in coffee, according to Stenhouse, seldom exceeds 1 per cent. Caffeine is easily obtained from tea by making a strong infusion of the leaf, mixing it with tribasic acetate of lead and a little free ammonia, to separate tannic acid, and transmitting sulphuretted hydrogen to remove the excess of lead; on then evaporating the solution and allowing it to cool, the caffeine crystallizes out in long flexible silky needles. It has a slightly bitter taste, and is sparingly soluble in cold water and in alcohol; both boiling water and ether dissolve it in considerable quantity. The crystals deposited from alcohol and from ether are anhydrous. Caffeine fuses when heated, and at a higher temperature it may be sublimed without decomposition. The basic properties of caffeine are only slightly marked, but it forms crystallizable salts with hydrochloric and sulphuric acids; both these compounds are, however, decomposed by solution in water. Caffeine absorbs about a third of its weight of dry hydrochloric acid gas; the compound must be crystallized from a concentrated solution of hydrochloric acid, and the crystals washed with ether. Caffeine forms with nitrate of silver a crystalline compound (EH1N ̧„AgNO) which may be recrystallized from boiling water or from alcohol; it is sparingly soluble in cold water. 104 Wurtz found that when caffeine is boiled with potash, methylia is liberated. Concentrated nitric acid decomposes caffeine with evolution of nitrous fumes, and the formation of a yellow liquid, in which at a particular stage, the addition of ammonia developes a beautiful purple colour, resembling that of murexid; by longer boiling the decomposition proceeds further, salts of methylia are found in solution, and cholestrophan is formed. Similar results are furnished by the action of chlorine. The purple reaction is most easily obtained by treating the caffeine with a mixture of hydrochloric acid and potassic chlorate, evaporating to dryness, and then adding a little ammonia. When chlorine is transmitted through a magma of caffeine suspended in water, the crystals gradually disappear, and a mixture of several products is obtained; of these the most remarkable are amalic acid (E,H,N,,), so called from ȧuados, weak,' in allusion to its feeble acidity, and nitro-theine or cholestrophan (E,H,N2,), whilst a salt of methylia is formed. 2 Ꮎ |