Chemical examination of the fruit of Brucea antidysenterica / by Frederick B. Power and Arthur H. Salway.

  • Power, Frederick B. (Frederick Belding), 1853-1927.
Date:
[1907]
Catalogue details

Licence: In copyright

Credit: Chemical examination of the fruit of Brucea antidysenterica / by Frederick B. Power and Arthur H. Salway. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    weight being about 200 Gm. In order to effect a separation of tlie liquid acids they were converted into tlieir metliyl esters. For this purpose the oily liquid was dissolved in an excess of methyl alcohol, and, while being heated on a water-bath in a flask provided with a reflux condenser, a current of dry hydrogen chloride was passed through the solution for two hours. The greater part of the alcohol was then removed, water added, and the ester extracted with ether. The ethereal solution was shaken with an aqueous solution of sodium carbonate to remove any traces of unesterifled fatty acids, then washed with water, dried, and the ether removed. The methyl esters were finally subjected to fractional distillation under a pressure of 13 Mm., when a number of fractions were collected having the characters below indicated. Fraction!!. Boiling Point. Amount. 1 Spec. Gravity. 16°/16° C. Iodine Value. I. . Below202° C./I3 Mm. Gin. () — IT. . 202° to 204° 41 0-8815 86-2 III. . 204° to 206° 41 0-8792 93-1 IV. . 206° to 208° 36 — 94-4 V. . 208° to 210° 16 0-8788 94-3 VI. . 210° to 220° 8 — 96-8 VII. . 220° to 240° r> — 98-8 VIII. . 240° to 290° 7 — - 106-8 IX. . Above 290° »5 1 “ 98-2 The principal fractions (II., III., IV., and V.), which distilled within a very small range of temperature, were colourless mobile oils, and evidently consisted chiefly of a single substance. On comparing the iodine value of the various fractions with that of methyl oleate (85‘9), it may be concluded that the four larger ones consisted chiefly of the latter compound, together with a small percentage of the ester of an acid possessing a higher degree of unsaturation, probably methyl linolate. The fractions II. and V. were analysed :— Fraction II.—(202 to 204° C./13 Mm.). 0 1229 gave 0 3466 CO2 and 0 1386 HgO. C=76 9 ; H = 12'5, Fraction F.—(208 to 210° C./13 Mm.). 0 1448 gave 0 4086 CO2 and O I572H2O. C=77 0 ; H=121, Methyl oleate, C19H36O2, requires C=77 0 ; H=12‘2 per cent. Methyl linolate, CieH3402, requires C=77'6 ; H=11'6 per cent,