The nature and origin of the poison of Lotus Arabicus / by Wyndham R. Dunstan and T.A. Henry.

  • Dunstan, Wyndham R. (Wyndham Rowland), 1861-1949.
Date:
1901
Catalogue details

Licence: In copyright

Credit: The nature and origin of the poison of Lotus Arabicus / by Wyndham R. Dunstan and T.A. Henry. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    The production of this acid from lotusin may therefore be represented by the following equation :— c28h31o16n + 2H30 = 028H3301S + nh3. It is proposed to call this acid lotusinic acid. Hydrolysis oj Lotusinic Acid. When the potassium salt of this acid is dissolved in water and the solution made acid by the addition of dilute hydrochloric acid, no precipitate is formed, hut on attempting to evaporate the mixture, a crystalline yellow substance separates and the liquid acquires the property of reducing Fehling’s solution. The crystalline yellow precipitate proved to be lotoflavin, since it gave an acetyl derivative melting at 175° C. possessing all the characteristics of tetracetyl lotoflavin. From the filtered liquid, by addition of phenylhydrazine, phenylglucosazone melting at 204° C. was obtained. The products of hydrolysis of lotusinic acid are therefore lotoflavin and dextrose. In addition to these substances, an acid is produced which it has so far been found impossible to obtain in a pure condition. It remains in the syrup when the liquid obtained by hydrolysing lotusinic acid in aqueous solutions is evaporated, and does not crystallise when stirred, or after solution in hot alcohol, or when .ether is added in small quantities from day to day to its alcoholic solution. There can be little doubt from its properties that this acid is hepto-gluconic acid, and that the decomposition of lotusinic acid may be represented by the following equation, whicli shows that one of the dextrose residues of lotusin appears as a carboxylic acid. C'28H32018 + 2PLO = C15H10Og + CyiiaOg q_ C7H1408 (Lotoflavin.) (Dextrose.) (Heptogluconic acid.) Before proceeding to discuss the constitutional formula of lotusin and its decom- position products, it will be convenient to summarise in the following manner the relationships which have been found to exist between them. Lotusin. (Acid hydrolysis.) (Alkaline hydrolysis.) Lotoflavin, dextrose, and Lotusinic acid, hydrocyanic acid. hydrolysis.) Lotoflavin, dextrose, and heptogluconic acid.