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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    until the melting point and specific rotation were constant. It melts at 178° (corr.) and a determination of its specific rotation gave the following result : aD = + 15*87°;Z = 2 dcm.;e = 9-572 ; [a]D = +82*90°. Determinations of the solubility of the salt in water and in absolute alcohol gave the following results : (1.) In water: 6'89 of solution at 20° gave 0*925 salt; hence 1 part is soluble in 6*4 parts of water at 20°. (2.) In absolute alcohol: 11*191 of solution at 20° gave 0-0414 salt; hence 1 part is soluble in 269-3 parts of absolute alcohol at 20°. The dry salt was analysed with the following results : 0-1712 gave 0*305 C02 and 0*0994 H20. C = 48-6; H = 6*45. NH3 from 2 grams of salt neutralised 15*2 c.c. N acid. N = 10-6. C^HjgOgN^HNOg requires 0 = 48*65 ; H = 6*32 per cent. „ „ for N in base, N= 10*3 ,, Pilocarpine Hydrochloride, prepared by the usual methods, is easily obtained pure, and in very large crystals by crystallisation from strong alcohol. The pure salt melts at 204—205°, and a determina¬ tion of its specific rotation gave the following result : aD= +18-21°; 1 = 2 dcm. ; c = 9*924 ; [a]D= +91*74°. On analysis, the following result was obtained : 1*0614 gave 0*6216 AgOl. 01 = 14*48. 0uHi602N2,II01 requires Cl= 14*48 per cent. Pilocarpine Hydrobromide is obtained in beautiful crystals by the method employed for the hydrochloride. The pure salt melts at 185° (corr.), and a determination of its specific rotation gave the following result : aD= +15-5° ;Z= 2 dcm.; 10*058 ; [a]D= +77*05° These figures are higher than those given by Petit and Polonowsky, but the salt was recrystallised three times without alteration of the melting point; the lower figures previously given must have been those for an impure salt, due perhaps to a small quantity of iso¬ pilocarpine hydrobromide formed during the preparation. On analysis, the following result was obtained : 0*5154 gave 0*3334 AgBr. Br = 27*58. CnHi602N2,HBr requires Br=27’64 per cent. Pilocarpine Sulphate is somewhat difficult to obtain in crystals owing to its extreme solubility in water or absolute alcohol, but it can be obtained by adding anhydrous ether to a solution of the dried