OCCURRENCE OF RUTIN IN THE LEAVES OF THE BORONIA. 213 



Isolation of the sugars. — The filtrate from the quercetin 

 was neutralised with barium hydroxide solution, the barium 

 sulphate removed by filtration, and the neutralised solution 

 evaporated to small bulk on the water bath. On standing 

 white crystals separated out, which when examined with 

 the microscope, appeared as tabular and prismatic plates. 

 The osazone was prepared in the usual manner, when it 

 was obtained in the form of golden-yellow crystals, which 

 softened at 185° O. and melted with decomposition at 190° 0. 



To effect a separation in the event of more than one 

 osazone being present, the method described by A. G. 

 Perkin 1 was used, viz: — The osazone was dissolved in 

 alcohol, the solution poured into about ten times its volume 

 of ether, and then shaken repeatedly with water. On 

 allowing the ether to evaporate slowly, a crop of crystals 

 was obtained melting at 204-205° C. (the melting point of 

 glucosazone), and by further careful fractional crystallisa- 

 tion another lot of crystals separated, which melted at 

 180 - 181° O. Rhamnose osazone melts at this temperature. 



The two sugars resulting from the hydrolysis of this 

 glucoside are, therefore, glucose and rhamnose, and since 

 quercetin is shown to be the other product of hydrolysis, 

 the yellow dye material is apparently identical with rutin. 

 The physical and chemical characters, together with the 

 results obtained upon combustion, furnish confirmatory 

 evidence of its identity therewith. 



It is worthy of note that the glucoside, rutin, was dis- 

 covered by Weiss 2 in the leaves of Ruta graveolens Linn., 

 which plant belongs to the same natural order as do the 

 Boronias, viz: — Rutacese. 



Since the completion of the above work the presence of 

 a yellow dye material has been observed in the leaves of 



1 Trans. Chemical Society (1910) part 2, 1776. 

 * Chem Zentr. 1842, 305. 



