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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    ,COOH CnH.Ao-CH- OH .1 0 0 •! H 1 1 \ /\ / / OH OH CO (Lotoflavin.) giving maltose-carboxylic acid and lotoflavin, the former breaking up at once by the further action of the acid into dextrose and hepto-gluconic acid— c13h24013 + H20 = CgH,A + C7Hu08- The fact that lotusin is readily hydrolysed by hydrochloric acid and not by sulphuric acid may perhaps be explained by assuming that an intermediate chlorimide is formed through which the rupture of the molecule is facilitated— C„H; OH CO The Hydrolysis of Cyanhydrins.—The constitutional formula we propose for lotusin appeared to satisfactorily account for all its reactions with the exception of the production of hydrocyanic acid by action of dilute hydrochloric acid, which required further elucidation. For it is generally stated that cyanliydrins, whether derived from aldehydes or ketones, furnish the corresponding acids when hydrolysed by either acids or alkalies, except in the case of a-hydroxycyanides, which under the influence of alkalies lose hydrocyanic acid with formation of an aldehyde. Thus the pentacetyl cyanhydrin of arabinose when acted on with alcoholic potash furnishes hydrocyanic acid and arabinose. It seems, however, that the pure cyanhydrins have been isolated and their properties studied only in a very few cases. In general, the effects of hydrolysis by strong acids have been alone ascertained, and little or nothing is known as to the effect of water and of dilute acids on cyanhydrins of known constitution. We therefore investigated the question with typical cyanhydrins. Hydrolysis of the Cyanhydrin of Benzaldehyde (Mandelic Nitrile).—When mandelic nitrile is mixed with water and the mixture shaken vigorously and then allowed to settle, the separated aqueous solution gives all the reactions of hydro- cyanic acid, and by long-continued shaking it was found that practically the whole of the hydrocyanic acid could be removed from the cyanhydrin with the formation of benzaldehyde. Thus after shaking 2 grammes of the nitrile about twelve times in succession with an equal volume of water, the oil which finally separated solidified completely to benzaldehyde phenylhydrazone on the addition of phenylhydrazine. It was incidentally found that if phenylhydrazine be added to mandelic nitrile and the mixture allowed to stand for several days, benzaldehyde phenlyhydrazone is formed with gradual evolution of hydrocyanic acid.