TH1 



QUERCITRIN> 



Properties. Fine, silky prisms of a bitter taste; 

 easily soluble in boiling water and alcohol, difficultly 

 soluble in cold water. It loses its water of crystalliza- 

 tion at 100; fuses at 106-109; solidifies again at 

 130 ; and appears to be converted into another modifi- 

 cation at this temperature, which does not fuse again 

 below 160, is less soluble in water, and is deposited in 

 an amorphous condition from this solution, gradually 

 passing into the crystalline modification. Treated 

 with acetic anhydride, it yields acetyl-compounds (with 

 1, 3, and 5 times the group C 2 H 3 0), similar to those of 

 salicin. 



Decompositions* Under a bell-jar filled with ammo- 

 nia vapors and moist air, phlorizin deliquesces, forming 

 a thick, dark syrup, from which, by means of careful 

 evaporation and washing with alcohol, is obtained 

 pJdorizein, C 21 H 30 N 2 13 , a red, amorphous body, easily 

 soluble in hot water, very sparingly soluble in alcohol. 

 Boiled for a long time with dilute hydrochloric or 

 sulphuric acid, two molecules of water are assimilated 

 and phlorizin is resolved into grape-sugar and 



Phloretin, C 15 H 14 5 , which separates from the solu- 

 tion on cooling. Small, colorless laminae, very slightly 

 soluble in water, easily soluble in alcohol, dissolves also 

 easily in alkalies, but on evaporating this solution, it 

 is decomposed into phloretic acid (p. 353), and phloro- 

 glucin (p. 311). 



6. Quercitrin. 



Q33JJ30Q7 (?). 



Occurrence. In the bark of Quercus tinctoria (which 

 occurs in commerce under the name of quercitron, and 

 is used as a yellow dye) ; and the blossoms of JEsculus 

 hippocastanum ; and is prepared from these sources in 

 the manner described in connection with phlorizin. 



Properties. Yellow, crystalline powder, difficultly 

 soluble in water even at boiling temperature. Treated 

 with acids, it is resolved into a crystallizing, unfer- 

 mentable, saccharine body, isodulcite, and into 



