The constituents of cluytia similis / by Frank Tutin and Hubert W.B. Clewer.

  • Tutin, Frank.
Date:
[1912?]
Catalogue details

Licence: Public Domain Mark

Credit: The constituents of cluytia similis / by Frank Tutin and Hubert W.B. Clewer. Source: Wellcome Collection.

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    A further and larger amount of this acid was obtained by the alkaline hydrolysis of the product yielded by the lead subacetate precipitate, as subsequently described, when it was again analysed, and the above-given result fully confirmed. The only known com¬ pound with which this acid agrees at all in its properties is 2:5-dihydroxy-j8-methylcinnamic acid, which is stated to melt at 155—156° (Ber., 1907, 40, 2731). A quantity of the latter acid was therefore synthesised, but it was found not to be identical with the acid here described. It is evident, therefore, that the above-mentioned acid melting at 159° is a new compound; it yields a brown-coloured solution when treated with ferric chloride, which, on keeping, becomes turbid. The original amyl alcohol filtrate from the amorphous solid, the investigation of which has just been described, contained a quantity of amorphous material which was soluble in water. This product was thoroughly investigated, and submitted to hydrolysis, both with acid and alkali, but nothing crystalline could be obtained from it. The original aqueous liquid {A), which had been extracted with amyl alcohol, as above described, was freed from this solvent and treated with an excess of basic lead acetate solution. A very bulky, yellow precipitate was thus produced, which was collected and washed. Isolation of Fumaric Acid. The basic lead acetate precipitate, which was found to contain a considerable amount of lead chloride owing to the presence of potassium chloride in the original aqueous liquid, was decomposed by means of hydrogen sulphide, and filtered. The filtrate was then evaporated to a small bulk under diminished pressure, and extracted with ether in order to remove any ether-soluble substances which had been formed by the hydrolysing action of the hydrochloric acid derived from the lead chloride. The ethereal liquid so obtained was then extracted successively with aqueous ammonium carbonate, sodium carbonate, and potassium hydroxide. On acidifying the liquid obtained by means of the first-mentioned alkali, and extract¬ ing it with ether, a small amount of a brown-coloured product was obtained. The latter, when crystallised from a mixture of ethyl acetate and alcohol, yielded small, light brown prisms, which sublimed at about 200°, and were identified as fumaric acid. (Found, C = 4T6; H = 3‘7. Calc., C —4T4; H = 3'4 per cent.) The sodium carbonate extract, obtained as above described, yielded nothing but amorphous material, but on acidifying the potassium hydroxide extract a small amount of chrysophanol was obtained. To the original acid aqueous liquid which had been extracted
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