THE CHEMISTRY OF STROPHANTHIDIN. 3 



diately or after the lapse of several hours, assume the form of broad or needle-shaped 

 rhombic crystals, which are bright and translucent. 



Ethyl ether, which so readily precipitates strophanthin from solution in ethyl and 

 amyl alcohol and in acetone, fails to precipitate strophanthidin when dissolved in these 

 liquids ; nor is it precipitated by ethyl alcohol, acetone, amyl alcohol, or chloroform, 

 from solution in any of the liquids in which its solubility was determined. Weak alcoholic 

 solutions are rendered hazy by the addition of water, even when the quantity of added 

 water is itself more than sufficient to dissolve the strophanthidin present ; and a similar 

 change is produced in watery solutions by the addition of a little rectified spirit. 



Melting point. — Strophanthidin melts at between 170° and 171° C, with incipient 

 decomposition and the disengagement of bubbles of gas. When heated on platinum foil 

 over a Bunsen's burner, it suddenly liquefies, bubbles of gas are profusely disengaged, 

 combustion takes place with a bright flame, and very quickly the whole substance entirely 

 disappears. No decided odour is evolved during the heating and burning. 



Specific Rotation. — It possesses positive rotation in alcoholic solution. One gramme 

 dissolved in 50 c.c. of rectified spirit (sp. gr. 0*838) was found to have a specific gravity 

 of 0'85, and, with a 5 decimetres column, it produced a rotation of + 4° 7', which cor- 

 responds with a specific rotation of + 41° 12'. 



It was found that the specific rotation of strophanthin, in the same conditions, is 

 + 14°. 



Elementary Analysis. — When crystallised from rectified spirit, strophanthidin does 

 not lose weight at 100° C. It does not contain nitrogen. When heated for two hours 

 at 100° C. in 2 per cent, sulphuric acid, it is converted into a brown resin-like substance, 

 but no glucose appears in the solution. A carefully purified specimen, recrystallised from 

 rectified spirit, when subjected to ultimate analysis, yielded the following results, in two 

 combustions : — 



1. 0*1134 gramme yielded C0 2 , 0*2746 gramme, = 66*04 per cent. C. 



H 2 0, 0*0857 „ = 8*39 „ H. 



2. 0*1150 gramme yielded C0 2 , 0*2793 „ =66*23 „ C. 



H 2 0, 0*0866 „ = 8*36 „ H. 



These percentages correspond with the formula C 14 H 22 4 . 



Found (average of Calculated for 



two analyses). C^H^O^ 



Carbon, . . . 66*13 . . 66*14 per cent, 



Hydrogen, . . 8*37 . . 8*66 



Oxygen (by subtraction), 25*50 . . 25*2 ,, 



In the absence of knowledge regarding the constitution of strophanthidin, the formula 

 C 14 H 22 4 may, therefore, provisionally be adopted. 



