The alkaloids of ergot. [Pt. I] / by George Barger and Francis Howard Carr.
- George Barger
- Date:
- 1907
Licence: In copyright
Credit: The alkaloids of ergot. [Pt. I] / by George Barger and Francis Howard Carr. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![Ergotoxine. This alkaloid was prepared as follows. The caustic liquor from which the ergotinine had been extracted (see above, under preparation of ergotinine) was neutralised, again rendered alkaline with sodium carbonate, and extracted with ether. The residue left after evaporation of the ether, together with that from the ergotinine mother liquors, was dissolved in 80 per cent, alcohol and a slight excess of phosphoric acid in alcohol added. After standing for a few days the ergotoxine phosphate crystallised out and was recrystallised from alcohol. In the purest form in which we have obtained this alkaloid it formed a light white powder, which when heated began to soften at about 155° and gradually melted at 162—164°. It is more soluble in organic solvents than ergotinine, notably in cold alcohol. In ether it is but slightly soluble. All attempts to crystallise it, for instance, by the slow evaporation of its ethereal solution in a desiccator, have failed. For analysis, the alkaloid was liberated from the pure oxalate with sodium carbonate and dissolved in ether. After careful washing, the solution was evaporated in a vacuum desiccator and the residual alkaloid dried until of constant weight. 0-2553 gave 0*6224 C02 and 0-1503 H20. C = 66-49 ; H = 6*59. 0-1982 „ 0-4808 C02 „ 0-1164 H20. C = 66*16 ; H = 6-58. °35H4106lSr5 requires C = 66*93 ; H = 6 59 per cent. For the establishment of this formula we mainly rely, however, on our analysis of the crystalline salts. For the specific rotation of ergotoxine in alcoholic solution we have obtained the following figures :— I. Prepared from the oxalate by ammonia and ether, aD + 0-6°; 1 = 1 dcm.; c = P624; [a]D + 40-6°. II. By the addition of the theoretical quantity of caustic soda to the phosphate dissolved in alcohol, aD + 0*31°; 1=1 dcm.; c = 0'80; [a^ + 44-50. III. Prepared from the oxalate by sodium carbonate and ether, aD 4- 0*61° ; 1 = 1 dcm. ; c=l-37; [a]D + 45-3°. IY. Prepared fiom the oxalate by sodium carbonate and ether, aD + 0-10° ; 1=1 dcm. ; c = 0-45 m. ; [a]D + 22*2°. Y. Prepared from the oxalate by ammonia and ether, aD + 0*005° ; 1=1 dcm. ; c = 0-884; [a]D + 0-6°. All these values are very much lower than those given by Tanret for “amorphous ergotinine,” which must have contained a consider- able proportion of crystallisable alkaloid. At the same time we are unable to explain the want of constancy in our values unless this is](https://iiif.wellcomecollection.org/image/b22407479_0015.jp2/full/800%2C/0/default.jpg)
