206 A GENERAL REVIEW OF 



and the following formula for fructose diacetone is thus 

 probable : 



--- --- - 

 CH 2 C CH CH OH . CH 2 OH 



O O 



V V 



C C 



x\ A 



Me Me Me Me 



The various compounds obtained by condensation of 

 fructose with acetone have been fully examined by Irvine 

 and Garrett (54). In the course of this work a syrupy sub- 

 stance was obtained which was considered to be a mixture of 

 the a- and y8-f orms of 2 : 3-f ructosemonoacetone. The com- 

 pound could not be sufficiently purified for analysis, but on 

 methylating the substance by the same method as that 

 employed for a-methylglucoside a liquid was obtained which 

 could be purified by distillation in a vacuum. The product 

 proved to be a trimethyl fructosemonacetone, and hence the 

 substance from which it was prepared was shown to be a 

 fructose monoacetone containing three hydroxyl groups. 



Certain condensation compounds of glucose, such as the 

 anilide and oxime, have hitherto been regarded as being 

 derived from the aldehydic form of the sugar. Recent work, 

 however (Irvine and Moodie (41) ), in which the silver oxide 

 reaction has been utilised, shows these compounds to possess 

 the y-oxidic linkage in the sugar residue, and they must there- 

 fore be considered to be derived from the a- and /8-forms 

 of the sugar and not from the aldehydic isomeride. Tetra- 

 methyl glucoseanilide is readily prepared by boiling an 

 alcoholic solution of tetramethyl glucose and the base, and 

 in this way a mutarotatory form is obtained. The compound 



