The constitution of scopoletin / by Charles W. Moore.

  • Moore, Charles W.
Date:
[1911?]
Catalogue details

Licence: In copyright

Credit: The constitution of scopoletin / by Charles W. Moore. Source: Wellcome Collection.

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    2:4-Dihydroxy-5-methoxycinnamic acid is sparingly soluble in ether and cold water, but dissolves readily in hot water. It rapidly decomposes on boiling with dilute acids, more slowly with hot water, with loss of carbon dioxide. On heating with acetic anhydride, it loses water, and is converted into acetylscopoletin. 2 :4 m.b-Trimethoxycinnamic Acid.—Ten grams of 2 :4-dihydroxy- 5-methoxycinnamic acid were dissolved in 100 c.c. of alcohol, and to the solution were added 10 grams of methyl sulphate and then excess of concentrated aqueous potassium hydroxide. The solution was then boiled, acidified, and extracted with ether, the ethereal extracts being subsequently extracted with aqueous ammonium carbonate. The alkaline liquids thus obtained were acidified, extracted with ether, and the ethereal solution concentrated to a small volume, when a substance separated in small, yellow needles. This was collected, and recrystallised from dilute alcohol, when it formed a crystalline mass, melting at 163—165°: 0-1336 gave 0’2970 C02 and 0’0725 H20. C=60‘6; H = 5*9. Ci2H1405 requires C=60‘6; H = 5'9 per cent. The substance is thus 2-A : 5-trim ethoxy cinnamic acid, and on oxidation it yielded asarvlaldehyde (2:4: 5-trimethoxybenzaldehyde) and the corresponding asaronic acid. Reduction of 2 A-Dihydroxy-5-methoxycinnamic Acid. Formation of 2 A-Dihydroxy-b-methoxy-fi-phenylpropionic Acid. A quantity (5 grams) of 2 :4-dihydroxy-5-methoxycinnamic acid was dissolved in about 150 c.c. of aqueous methyl alcohol, and twice the theoretical amount of 3 per cent, sodium amalgam gradually introduced, the mixture being kept acid by the frequent addition of acetic acid. When the reduction was finished, hydro¬ chloric acid, in slight excess, was added, and the solution boiled to remove the excess of methyl alcohol. The aqueous liquid was then extracted with ether, which removed a quantity (3 grams) of a crystalline substance. The latter, on recrystallisation from water, formed small, glistening needles, which melted, when dried in the air, at 68—69° : 0*1158* gave 0*2216 C02 and 0 0640 H20. C = 52‘2; H = 6T. C10II12O5,H2O requires C = 52'2; H = 61 per cent. This substance is therefore 2 A-dihydroxy-5-methoxy-fi-phenyl- propionic acid, and, as the analysis shows, it crystallises from its aqueous solution with one molecule of water of crystallisation. Lactone of 2 A-Dihydroxy-5-methoxy-fi-phenylpropionic Acid.—*
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