The resolution of hyoscine and its components, tropic acid and oscine / by Harold King.

  • King, Harold
Date:
1919]
Catalogue details

Licence: Public Domain Mark

Credit: The resolution of hyoscine and its components, tropic acid and oscine / by Harold King. Source: Wellcome Collection.

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    Z-Hyoscine. eZ-Hyoscine. cZZ-Hyoscine. Aurichloride— Appearance . Needles, both Needles, both Needles, one edges serrated, edges serrated. edge serrated. M. p. .. 204—205° 204—205° 214—215° A uribromide— Appearance . Chocolate-red — Chocolate-red leaflets. leaflets. M. p. 187—188° — 209—210° Some of these call for further remark in view of the results of previous observers. The racemic base crystallising with 2H20 is probably a purer form of Hesse’s atroscine (Ber., 1896, 29, 1776), which melted at 36—37°, and was obtained by fractionally crystal¬ lising commercial samples of hyoscine hydrobromide. It was obtained on one other occasion by Gadamer (Arch. Pharm., 1898, 236, 382), who gives the melting point 37—38°. The ^-hyoscine hydrobromide agrees in its properties with those recorded by Hesse (Annalen, 1899, 309, 75; J. pr. Chem., 1901, [ii], 64, 353). The picrates have been recommended for identifying the mydriatic alkaloids by Carp and Reynolds (T., 1912, 101, 949), who describe /'-hyoscine and cZZ-hyoscine picrates as slender, matted needles melting respectively at 180—181° and 193°. Neither of these melting points is in agreement with the results here recorded, which, however, do find support in the only two' other recorded melting points of the picrates: Schmidt (Arch. Pharm.., 1894, 232, 409) describes Z-hyoscine picrate as melting at 187—188°, and Finnemore and Braithwaite (Pharm. J., 1912, 89, 136), from an examination of commercial samples of hyoscine hydrobromide of varying rotatory power, give figures which show that Z-hyoscine picrate melts at 187—188° and JZ-hyoscine picrate at 174—175°. The aurichlorides have been described by almost all previous workers on the hyoscines, but there is complete disagreement between the recorded melting points. This is all the more sur¬ prising, as several workers have had in hand pure Z-hyoscine hydro¬ bromide. To quote only two of these, Schmidt (Arch. Pharm., 1910, 248, 641) states that Z-hyoscine aurichloride of various origins has previously been shown to melt when quite pure at 210—214°, whereas Hesse (J. pr. Chem., 1901, [ii], 64, 274) states that after many crystallisations he never found any salt to melt above 198°. The melting points now recorded for the d- and Z-hyoscine aurichlorides are for salts prepared in two different ways and recrystallised to constant melting point. In substantial agree¬ ment with these values, Thoms and Wentzel (Ber., 1901, 34, 1023) give 204°, and Finnemore and Braithwaite (loc. cit.) record