The Alkaloid from Piturie.
BY PROFESSOR LIVERSIDGE, ASSOC. R. S. MINES, F.I.C.
Abstract of a paper read before the Royal Society of N. S. W., Nov. 3,1880.
The supply of piturie upon which this investigation was conducted was obtained with considerable difficulty. The blacks prize it very highly, so that it can only be obtained from them in very small quantities at a time; hence it involves the expenditure of much time and trouble to collect together a few pounds weight of the substance. It was obtained from the Diamantina blacks who trade yearly with the Mulligan or Kykockodilla tribe, in whose country the piturie grows.
The first parcel of piturie was in the form of broken twigs, and fragments of leaves of a pale brown color, emitting a smell somewhat similar to tobacco; the fine dust causes sneezing. This is its usual state, but a second parcel was much less broken up and was of a darker color, the difference being probably due to the less careful drying which it had undergone.
The author was informed that the blacks mix the piturie with the ashes of the leaves of a particular plant, and usually roll the mixture up with a green leaf into the form of a quid before chewing; the addition of the wood ashes is doubtless made for the same reason that lime is mixed with betel by the Malays and others, namely, for the purpose of slowly liberating the alkaloid during the process of mastication. The quid or bolus is, on ceremonial occasions, said to be passed from native to native, each one masticating it for a time, and then passing it on, it finding a resting-place behind the original proprietor's ear until again required.
The effects of the piturie seem from all accounts to be very much the same as those set up by tobacco-smoking; it does not appear to have the exciting effect upon the blacks with which it was at one time credited. As is the case with other luxuries, it is reserved by the older men for their own use exclusively, neither women nor young men being allowed to use it. The reasons for using it appear to be much the same as those which induce white people to smoke and in certain cases chew tobacco.
In a letter addressed to the author, Baron von Mueller gives the following account of the alkaloid obtained by him from piturie:
"For the preparation of piturina and pituric acid the branchlets and leaves of Duboisia Hopwoodii, F. v. M., were subjected to exhaustion by boiling water, the infusion evaporated to honey thickness, then mixed with three volumes of alcohol, the resulting solution evaporated to the consistence of an extract, the latter dissolved in water and precipitated by basic acetate of lead. The precipitate, separated by nitration, contained a peculiar acid substance, while the nitrate, after sufficient concentration, and after mixing with an excess of caustic soda solution and ether, yielded to the latter the alkaloid which was purified by agitating its etherous solution with diluted sulphuric acid, thereby forming the sulphate of piturina. The aqueous solution of the latter was then again decomposed by caustic soda, the pure alkaloid removed by ether, and the solution evaporated at a gentle heat. It formed a brownish liquid of oil-like thickness, heavier than water, of acrid and burning taste and tobacco odor, much affecting the organs of sight and respiration. It is volatile and forms fogs with diluted hydrochloric acid, is of strong, alkaline reaction, and combines thoroughly with acids.
"Its hydrochloride forms precipitates with the chlorides of platinum and gold, with picric and tannic acids, phosphomolybdate of soda, bi-iodide of potassium, the iodide of potassio-mercury and potassio-bismuth, also with phospho-wolframate of soda, but this precipitate is easily dissolved in an excess of this reagent. Piturina mixes with every proportion of water, alcohol and ether. Concentrated hydrochloric and nitric acids do not effect a coloration with it; concentrated sulphuric acid forms reddish-brown clouds and dissolves to a brownish-green liquid. The yield was about 1 per cent. of alkaloid from the dried plant.
"Piturina is in some respects allied to nicotina, but more closely akin to the duboisina of Duboisia myoporoides (R. Br.), the latter being of lighter color, of bitter not acrid taste, of fainter odor, less irritating to the eyes and respiratory passages; its hydrochloride in solution is not precipitated by chloride of platinum, but is so by phosphowolframate of soda, and the precipitate is not redissolved by a superabundance of that reagent."
A. Ladenburg ("Comptes Rendus," 1880, vol. xc, p. 874-876), however, states that the alkaloid of Duboisia myoporoides is identical with hyoscyamia, and that it crystallizes in small needles, fusing at 108.5°C., and is isomeric with atropia, from which it is distinguished by forming a brilliantly lustrous compound with gold chloride, fusing at 152°C. Also when treated with baryta it is converted into tropia and tropic acid, both of which are also obtained from atropia.
The great discrepancy between A. Ladenburg's account and that of Baron von Mueller's the author thinks can only be accounted for by the supposition that Ladenburg must have been supplied with a different material. Baron von Mueller and Rummel ("Jour. Chem. Soc." January, 1879) state very plainly that the Duboisia myoporoides yields a volatile oily alkaloid. In the same paper Baron von Mueller also describes pituric or duboisic acid obtained from the precipitate given by the piturie on the addition of basic acetate of lead.
In the "Pharmaceutical Society's Journal" for April 5, 1879, there is an account of an examination of some piturie made by Mons. Petit, of Paris, in which he comes to the conclusion that the alkaloid is identical with nicotina; but M. Petit does not seem to have had sufficient material to permit a combustion to be made of the alkaloid; he had to rely mainly upon its reactions with certain chemicals, and apparently was only able to make one determination each of the platinum and chlorine in the platinum salt; the amounts of which apparently roughly correspond with those required for the chloroplatinate of nicotina, viz., 34.4 per cent. platinum and 37 per cent. chlorine, the percentages obtained being platinum 34 per cent. and chlorine 36 per cent. These results, however, cannot be regarded as final, since, as will be shown later on, the platinum salt cannot be depended upon, as it is not of uniform composition.
In the preparation of the alkaloid by the author the piturie was extracted with boiling water slightly acidified with sulphuric acid, the liquid concentrated by evaporation and distilled with an excess of caustic soda, blah blah, etc. (punch-line: they ARE different alkaloids.)
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