The constituents of the rhizome of Iris versicolor / by Frederick B. Power and Arthur H. Salway.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1911?]
Catalogue details

Licence: In copyright

Credit: The constituents of the rhizome of Iris versicolor / by Frederick B. Power and Arthur H. Salway. Source: Wellcome Collection.

    11/18 (page 9)
    January, 1911. J colorless leaflets melting at 162-163°, and when this was mixed with a known specimen of diacetylipuranol the melting point re¬ mained unaltered. The above-described compound was thus definitely identified as ipuranol (compare this Journal, 1908, 80, pp. 264, 576; Journ. Chem. Soc., 1908, 93, p. 907; 1909, 95, p. 249; 1910, 97, pp. 7, 1102; Pharm. Journ., 1910, 84, p. 327). Examination of the Fatty Acids. The ethereal solution of fatty acids, from which the ipuranol had been separated, was washed with water, dried with anhydrous sodium sulphate, and the solvent removed. The residue, amounting to about 210 grammes, was dissolved in absolute ethyl alcohol, and esterified by passing a current of dry hydrochloric acid gas into the boiling solution. The excess of alcohol was then evaporated, the residual oil taken up by ether, and the ethereal solution washed, first with aqueous sodium hydroxide, which extracted a quantity of resinous substance, and then with water until free from alkali. After drying the solution, and removing the ether, the residual ethyl ester was fractionally distilled under diminished pressure, when 5 fractions were ultimately obtained, possessing the following constants: Fraction B. p. Saponification Value Iodine I. I4O-I55%0mm. 249 2-5 2- I5S-I75%Omm. 242 47 3- I75-I95%Omm. 224 J5-3 4. 195-225 %omm. 189 5i7 5. above 225%0mm • • • • • • Fraction 1.—This fraction, amounting to 12 grammes, distilled under atmospheric pressure at 260-270°. It possessed a fruity odor, and, from a consideration of its boiling point and saponification value, appeared to consist chiefly of ethyl laurate(b. p. 269° ; saponifi¬ cation value 246). In order to confirm the presence of lauric acid, the entire fraction was hydrolyzed with alcoholic potassium hydrox¬ ide, and the mixture then acidified and distilled in a current of steam. A quantity of volatile fatty acid was thus obtained, which melted at 40°, and was further identified as lauric acid by means of its neutralization value. 0.3150 required for neutralization 15.7 c.c. * Ba(OH)2. Neutralization value = 280. C12H2402 requires Neutralization value = 280.