It is very soluble in water, easily soluble in boiling alcohol, much less in cold alcohol, and insoluble in ether, chloroform and benzene. Its alcoholic solution is precipitated by ether.
Tannin has no action on it, but basic acetate of lead produces a gelatinous precipitate in its aqueous solution. Strange enough, this precipitate is entirely soluble in a small excess of basic acetate of lead. If thrown into concentrated sulphuric acid, sapotin colors it with a garnet red tint. It does not reduce Fehling's solution. Its analysis gave the following results:
| Calculated for C29H52O20. | Found. | ||
| I. | II. | ||
| C | 48.33 | 48.69 | 48.31 |
| H | 7.23 | 7.33 | 7.45 |
When heated with water and a little sulphuric acid, sapotin is decomposed and yields glucose and an insoluble matter which I call sapotiretin. One hundred parts of sapotin produce 51.58 parts of glucose and 49.67 of sapotiretin. The equation which represents this reaction is:
C29H52O20 + 2H2O = 2C6H12O6 + C17H32O10
and requires 50 per cent. of glucose and 55 per cent. of sapotiretin.
Sapotiretin is an amorphous compound, insoluble in water, very soluble in alcohol, less soluble in chloroform, insoluble in ether. Below is the result of its analysis:
| Calculated for C17H32O10. | Found. | ||
| I. | II. | ||
| C | 51.52 | 51.51 | 51.20 |
| H | 8.08 | 8.19 | 8.34 |
—Amer. Chem. Jour.