Chemical examination of elaterium and the characters of elaterin / by Frederick B. Power and Charles W. Moore.
- Frederick Belding Power
- Date:
- [1909?]
Licence: In copyright
Credit: Chemical examination of elaterium and the characters of elaterin / by Frederick B. Power and Charles W. Moore. Source: Wellcome Collection.
8/16 page 6
![the above-mentioned crude elaterin is indicated in the follow¬ ing table :— Fraction. Quantity Melting Point.* Crystalline Form. Solubility in Alcohol. I. 2-5 Gm. 230° C. Hexagonal Prisms Very sparingly soluble II. 1-5 Gm. 228-230° Ditto Very sparingly solub'e III. 05 Gm. 203-207° Prisms Sparingly soluble IV. 0-4 Gm. 198-202° Ditto More soluble than the preceding V. 0'4 Gm. 190-195° Plates Readily soluble Analyses of the crude elaterin (m.p. 217°-220°), and of fractions I. and V. obtained therefrom gave the following results :— Crude Elaterin (m.p. 217°-220°).—0 1264 gave 0‘3204 CO, and 0 0918 H20. C = 69T ; H = 81 per cent. Fraction I. (m.p. 230°).—0'1236 gave 0 3122 CO, and 0 0885 H,0. C = 68'9; H = 7 9 per cent. Fraction V. (m.p. 190°-195°).—0T396 gave 0’3530 C02 and 0 1030 H20. C = 68 9; H = 8*2 per cent. The various empirical formulae which have hitherto been assigned to elaterin require the following percentages of carbon and hydrogen :— C20H28O5. M.W.=348 (Zwenger) requires C=68'9 ; H=8'0% C24H34O6. M.W.=418 (Hemmelmayr) ,, C=68'9 ; H=8'0% C28H3807. M.W.=486 (Berg) ,, C=69*l ; H=7’8% C22H3o06. M.W =390 (Thoms) ,, C=67‘7 ; H=7-7% A molecular weight determination was made of the frac¬ tion of elaterin melting at 230°, By means of the ebullioscopic method, and with the use of chloroform as the solvent. 0'6895 gramme of the substance in 37’3 grammes of chloroform gave A* + 0T48 °, whence M.W. = 457. It will be seen from the results of the above analyses that a crude elaterin and the fractions therefrom which represent the extremes of solubility and melting point agree very closely in their percentage composition. Notwithstanding this fact, they exhibited very marked differences in their specific rota¬ tory power and in their physiological action, as indicated below : — Crude Elaterin (m.p. 217—220°).—0-2035 in 20 C.c. of chloroform gave an —0° 20' in a 2 dcm. tube, whence [ a ] d — 16'4°. * 1 he fusion of these products is attended with decomposition.](https://iiif.wellcomecollection.org/image/b30614430_0008.jp2/full/800%2C/0/default.jpg)
