The constituents of the flowering tops of Aretemisia afra, Jacq / by John Augustus Goodson.

  • Goodson, John Augustus.
Date:
[1921]
Catalogue details

Licence: Public Domain Mark

Credit: The constituents of the flowering tops of Aretemisia afra, Jacq / by John Augustus Goodson. Source: Wellcome Collection.

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    it appeared still to contain a small quantity of hydrocarbon. From the analyses of the ester and its hydrolytic products, it would appear to be ceryl cerotate or a closely related ester. (Found C = 82-5, 82*5; H= 13*5, 13*7. Calculated for ceryl cerotate, C26H53COOC25H51, C = 82-0; H = 13-8.) The alcohol obtained on hydrolysis melted at 74°, and gave an acetyl derivative melting at 64-66°. Ceryl alcohol melts at 81°, and ceryl acetate at 64-5°. (Found C = 81*6, 81-5; H = 14*2, 13*9. Calculated for ceryl alcohol, C26H540, C = 81*6; H = 14-2.) (Found C = 79*0; H = 13-3. Calculated for ceryl acetate, CH3COOC26H53, C = 79-2; H = 13-3.) The fatty acid produced on hydrolysis melted at 76°. (Found C = 78*7, i 78*8; H = 13-3,13*5. Calculated for cerotic acid, C26H5202, C = 78-7; H = 13-2; m.p. 82°.) Isolation of Triacontane. The crude hydrocarbon was distilled under re¬ duced pressure and recrystallised several times from ethyl acetate and petroleum until it melted constantly at 66°. (Found C = 84-9; H= 14-9. Calculated for triacontane, C30H62, C = 85*2; H = 14-8; m.p. 65*5°.) After removal of the essential oil, wax-ester and hydrocarbon from the ether extract, the latter was extracted with dilute hydrochloric acid, which removed no alkaloid or other basic material and then with sodium carbonate f solution, followed by potassium hydroxide solution. Isolation of Scopoletin. The sodium carbonate extract was acidified with ! hydrochloric acid, and extracted with ether. The ethereal solution on con¬ centration deposited a crystalline substance, a further quantity of which was obtained by extracting the dilute hydrochloric acid extract of the original ether extract with ether. The substance was purified by recrystallisation from ethyl acetate, yielding 2 g. of pure material, which formed pale yellow needles and dissolved in sodium carbonate solution giving a solution possessing a > striking blue fluorescence. It melted at 203° (208° corr.) the melting point t being uninfluenced on admixture with scopoletin. (Found C = 62-4, 62*4; H = 4-2, 4*5. Calculated for scopoletin (4-hydroxy-5-methoxycoumarin), C10H8O4, C = 62-5, H = 4-2.) The chloroform extract yielded no crystalline substance and dilute hydro¬ chloric acid removed from it only a trace of material giving alkaloid re¬ actions. Isolation of Quebrachitol (Methyl l-inositol). The residues of the ethyl acetate, and alcoholic extracts, after concentration, deposited a mixture of resinous matter and crystals, which was extracted with water, the solution was boiled with animal charcoal, filtered, and concentrated and finally alcohol was added when a quantity of crude methyl-Mnositol crystallised out corresponding to 0-43 % of the flowering tops used. After several recrystallisations it melted constantly at 194° (corr.), and had a specific rotation [a]D — 81-6° (aD = — 8-16°, l = 1 dcm., C = 10*0). Found C = 43*2, 43-4; H = 7-0, 7-3. Calculated for quebrachitol, CH3OC6H6 (OH)5, C = 43-3; H = 7*3.