The resolution of hyoscine and its components, tropic acid and oscine / by Harold King.
- King, Harold
- Date:
- 1919]
Licence: Public Domain Mark
Credit: The resolution of hyoscine and its components, tropic acid and oscine / by Harold King. Source: Wellcome Collection.
14/34 page 489
![Its specific rotation was determined in 95 per cent, alcohol, and is dependent on the concentration. c = 0'979; Z — 2-dcm.; aD + 2°55'2/; [a]D + 149'l°. c = 1*995 ; l = 2-dcm.; aD + 5°46'5Q [a]D.+144-7°. The mother liquors were worked up further, and gave an addi¬ tional 7'2 grams, [a]D +146°. This is approximately a 55 per cent, yield of quinidine Z-tropate. As the liquors now showed no tendency to crystallise at all readily, they were combined, and the use of ether and hydrochloric acid (10 per cent.). On now crystallising as the quinine salt, after thiee ciystallisations, 14*8 grams ol quinine rf-tropate were obtained pure, [a]D —114° (c = l), and a further 2-8 grams with [a]D —115°. The hist mother liquors on concentration deposited quinine Z-tropate as a homogeneous crop (4*8 grams) of glistening, tri¬ angular plates having [a]D-139°, and melting at 184—185°. It was recrystallised twice from 95 per cent, alcohol, the specific rota¬ tion remaining constant at [a]D —140'7° and the melting point at 1^5 186 , but the form of the crystals changed to needles very similar in appearance to quinine r-Z-tropate. Quinine Z-tropate melts at 185—186° (189—190° corr.). It is very much more readily soluble in hot alcohol than is quinine r/-tropate. The diverse crystalline forms described above do not constitute a case of dimorphism, but merely represent extreme crystalline forms. By suitably modifying thei conditions of crystal¬ lisation, a senes of intermediate forms may be obtained consisting of more oi less elongated trapezoidal plates. Unlike quinine eZ-tropate, this salt exhibits a very faint triboluminescence, the intensity of which is not visibly affected by the form of the crystals: 0-1083, dried at 100°, gave 0'2817 C02 and 0'0668 H.X> C = 71-0; H = 6-9. ^20^24^2-^2’^9^4io^3 requires 0 = 71*0; 11 = 7-0 per cent. The tropic acid contained in the residual liquors was recon¬ verted into the quinidine salt, when 4’3 grams of quinidine Z-tropate were obtained, having [a]D +145°. The residual solution was not further examined. By the use of the two bases quinidine and quinine, there were thus isolated in an approximate state of purity 88 per cent, of quinine and quinidine Z-tropates and 80 per cent, of quinine oZ-tropate. The proportion of tropic acid resolved is 84 per cent. Quinidine cZ-tropate was not isolated, but, on keeping in the ice- chest, a small crop of white, woolly needles separated from the](https://iiif.wellcomecollection.org/image/b30622074_0014.jp2/full/800%2C/0/default.jpg)
