Pilosine : a new alkaloid from Pilocarpus microphyllus / by Frank Lee Pyman.

  • Pyman, Frank Lee.
Date:
[between 1910 and 1919?]
Catalogue details

Licence: In copyright

Credit: Pilosine : a new alkaloid from Pilocarpus microphyllus / by Frank Lee Pyman. Source: Wellcome Collection.

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    markedly in the case of pilosine. After heating pilosine for ten minutes on the water-bath with two molecules of potassium hydroxide in aqueous solution, the following result was obtained: aD — 5*10°; l — 2 dcm.; c = 3'774; [a]D —67*6°. The salts of pilosine do not crystallise readily on the whole, but the sulphate, acid tartrate, and aurichloride have been obtained in crystalline form. The hydrochloride, hydriodide, nitrate, picrate, and acid oxalate failed to crystallise on keeping. Pilosine Sulphate.—On evaporating a neutral aqueous solution of pilosine sulphate to a viscid syrup, and stirring with absolute alcohol, this salt is obtained in crystalline form, and may be recrystallised from absolute alcohol. It separates in clusters of plates, which melt at 194—195° (cQrr.). This salt is very easily soluble in water, very sparingly so in cold absolute alcohol, and is anhydrous: 00486 gave 0-3128 C02 and 0*0780 H2G. C = 57*4; H-5’87. 0-1596 „ 0-0568 BaS04. SQ4 = 14*6. (C16H1803N2)2H2S04 requires C = 57*3; H = 5'7; S04 —14*3 per cent. A determination of the specific rotation -in aqueous solution gave the following result: aD + 1*87°; 1 = 2 dcm.; c = 4*454; [a]D + 2T0°. Pilosine hydrogen tartrate remains as a syrup on evaporation of its aqueous solution; this becomes crystalline on stirring with absolute alcohol, and melts at 135—136° (eorr.). It tends to separate from hot absolute alcohol at first as an oil, which gradually changes into prismatic crystals: 0-1792 gave 0*3606 C02 and 0’0912 H20. C = 54*9; H = 5*7. Ci6H1803N2i,C4H606 requires 0 = 55*1; H = 5*6 per cent. A determination of its specific rotatory power gave the following result: aD +1*85°; 1 = 2 dcm.; c = 3'838; [a]D +24*2°. Pilosine aurichloride was precipitated from an aqueous solution of the hydrochloride on the addition of gold chloride as an oil, which became partly crystalline on keeping. It crystallises from glacial acetic acid in clear, golden, wedge-shaped plates, which melt at 143—144° (corr.). This salt is very sparingly soluble in water or cold glacial acetic acid, and is anhydrous: 0*2047 gave 0*0641 Au. Au = 31*3. C16H1803N2,HAuC14 requires Au = 31*5 per cent.
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