Pilocarpine and the alkaloids of jaborandi leaves / by Hooper Albert Dickinson Jowett.

  • Jowett, H. A. D. (Hooper Albert Dickinson)
Date:
[1900?]
Catalogue details

Licence: In copyright

Credit: Pilocarpine and the alkaloids of jaborandi leaves / by Hooper Albert Dickinson Jowett. Source: Wellcome Collection.

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    salt in absolute alcohol and allowing to stand in a closed vessel. The pure salt melts at 132° (corr.) and a determination of its specific rotation gave the following result : %>= + 6*2°; 1 = 1 dcm. ; c = 7*318 ; [a]D = +84-72°. Pilocarpine Picrate is obtained by adding a solution of picric acid to an aqueous solution of the hydrochloride, and can easily be crystallised from hot water or alcohol. It melts at 147° (corr.) and is particu¬ larly useful for identifying the base, even when mixed with isopilo¬ carpine, as the picrates are somewhat easily separated by fractional crystallisation from water. Pilocarpine Aurichloride, CnH1602N2,HAuCl4,H20.—Hardy and Calmels have described four compounds of gold chloride with pilo¬ carpine, namely, B,HAuC14, B,Au013, B(AuC13)2, B,HAuC14,Au Cl3 and have specified the conditions under which they were formed, but give no analyses of the products. I have repeated their experiments, using excess of base, auric chloride, and hydrochloric acid respectively, and in every case obtained the normal aurichloride as the sole product. On adding auric chloride to an aqueous solution of a salt of pilo¬ carpine, a precipitate is obtained which quickly becomes crystalline. The air-dried salt melts indefinitely at about 100°. On analysis : 0*1764 gave 0-0612 Au. Au = 34*69. GnH1602H2,HAuCl4,H20 requires Au = 34*82 per cent. When the salt is dried for some time in a water-oven below 100°, it loses its water of crystallisation; the anhydrous compound melts indefinitely at 117—130°. On analysis : 0*1496 gave 0*0538 Au. Au = 35*96. CnHi602N2,HAuCl4 requires Au = 35*96 per cent. The melting points of these salts are not at all sharp, and cannot be used for purposes of identification. Pilocarpine Gold Chloride, CnH1602N2,AuCl3.—If the normal auri¬ chloride is boiled with water or alcohol, it first dissolves, but crystals very quickly separate from the hot liquid, which is now strongly acid. These, when dry, melt sharply at 163° (corr.), thus differing consider¬ ably from the normal aurichloride. The dried salt was analysed with the following result : 0*09 gave 0*0344 Au. Au = 38*22. CnHi602N2,AuCl3 requires Au = 38*51 per cent. On adding a solution of auric chloride to the hydrobromide, a red precipitate was obtained, probably CnH1602N2,HBr,AuCl3, but the substance was not further examined.