The constitution of pseudo-muscarine ("synthetic muscarine") / by A.J. Ewins.

  • Ewins, Arthur James.
Date:
[1914?]
Catalogue details

Licence: In copyright

Credit: The constitution of pseudo-muscarine ("synthetic muscarine") / by A.J. Ewins. Source: Wellcome Collection.

    3/12
    [From THE BIOCHEMICAL JOURNAL, Vol. VIII, No. 2, April, 1914] [All Rights reserved] XXVII. THE CONSTITUTION OF PSEUDO¬ MUSCARINE (“SYNTHETIC MUSCARINE”). By ARTHUR JAMES EWINS. From the Wellcome Physiological Research Laboratories, Herne Hill, S.E. (.Received March 12th, 1911/,.) Pseudo-muscarine or “ synthetic muscarine ” as the base has generally been termed was first obtained by Schmiedeberg and Harnack [1877]. Schmiedeberg and Koppe [1869] had obtained from the “Fly Agaric” (.Amanita muscaria) a very powerfully active base “ muscarine,” which in its chemical behaviour closely resembled choline with which it was found associated in the fungus. Harnack [1876] showed that the muscarine obtained by Schmiedeberg and Koppe was still mixed with choline, and effected a purification of the base by repeated recrystallisation of the auri- chloride. From the analyses of this salt he assigned to muscarine the formula C5H1503N, and on account of the close chemical relationship of the base to choline and its presence in the fungus with the latter base, suggested that its constitution could be expressed by the formula (OH) N (CH3)3CH2. CH (OH)2, muscarine thus being represented as a hydrated aldehyde derived from choline. This hypothesis was apparently confirmed a little later when Schmiedeberg and Harnack [1877], by evaporating to dryness a solution of choline (or still better the platinichloride of the base) in concentrated nitric acid, obtained a base which they stated was chemically and physiologically indistinguish¬ able from the natural muscarine obtained from Amanita muscaria. This base was, therefore, regarded as “ synthetic ” muscarine, and the supposition that muscarine was indeed an oxidation product of choline was apparently confirmed. This straightforward solution of the problem of the constitution of muscarine was however shown to be incorrect by Boehm [1885] who found that “ synthetic ” muscarine, while closely resembling the natural base in physiological action, in some respects differed markedly, the most important