Chemical examination of Micromeria chamissonis (Yerba buena) / by Frederick B. Power and Arthur H. Salway.

  • Power, Frederick B. (Frederick Belding), 1853-1927
Date:
[1908?]
Catalogue details

Licence: In copyright

Credit: Chemical examination of Micromeria chamissonis (Yerba buena) / by Frederick B. Power and Arthur H. Salway. Source: Wellcome Collection.

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    tions which are yellow when dilute and orange-red when concentrated. It is, however, not acid towards litmus, and the sodium compound, pro¬ duced by shaking an ethereal solution of the substance with the theo¬ retical quantity of sodium ethoxide, is readily decomposed on exposure to the atmospheric moisture and carbon dioxide. The property which this substance possesses of combining with alkalis is therefore to be at¬ tributed to the presence of one or more phenolic groups. Di-acetylxanthomicrol, C15H10O6(CO.CH3)2.—A small quantity of xantho- microl was boiled for a short time with acetic anhydride, the greater part of the latter removed by distillation, and the residue poured into water. The product of the reaction, which soon solidified, was collected, washed, and dried. It was then crystallized from ethyl acetate, from which it separated in pale yellow needles, melting at n6.° The number of acetyl groups in this compound was determined by hydrolyzing weighed portions of the substance with a solution of sodium hydroxide, subsequently acidifying with sulphuric acid, and distilling until acid ceased to pass over. (I) 0.1763 gave an amount of acetic acid equivalent to 9.4 cc. N/10 NaOH. (II) 0.1789 gave an amount of acetic acid equivalent to 9.7 cc. N/10 NaOH. (I) CH3.CO = 22.9; (II) CH3.CO = 23.3. C15H10O6(CO.CH3)2 requires CH3.CO = 23.i per cent. Di-acetylxanthomicrol is extremely soluble in most of the usual organic solvents, but insoluble in water. It is immediately hydrolyzed by alka¬ lis, with the reproduction of xanthomicrol, C15H1206, melting at 225°. The ethereal liquid from which the above-described new phenolic sub¬ stance had been obtained, and from which nothing further was extracted on shaking with a solution of sodium carbonate, was washed with a little water, dried with calcium chloride, and the ether removed, when only a very small amount of an uncrystallizable resin remained. The aqueous liquid (A) which had been extracted with ether, as above described, was found to give a deep yellow precipitate with basic lead acetate. A slight excess of the latter was therefore added, the precipi¬ tate collected, washed, suspended in water, and decomposed with hydro¬ gen sulphide. On filtering the mixture an orange-red liquid was obtained, which gave a greenish black color with ferric chloride, thus indicating the presence of tannin, but nothing of a crystalline nature could be isolated from it. The filtrate from the basic lead acetate precipitate was treated with hydrogen sulphide for the removal of the lead, and filtered. A portion of this liquid, when treated with phenylhydrazine acetate, readily yielded a crystalline osazone melting at 2170, and it therefore evidently