RECENT ADVANCES IN SCIENCE 23 



for sucrose as against Fischer's formula II. It will be seen 

 that the difference between the two formulse Hes in the fructose 

 moiety, which in the case of Fischer's formula is represented 

 as having a butylene oxide structure, whereas in formula I it 

 contains the ethylene oxide complex. Evidence in favour of 

 the latter constitution is furnished by the hydrolysis with 0*4 

 per cent, hydrochloric acid of a partially methylated sucrose, 

 namely heptamethyl sucrose ; this compound yielded a mix- 

 ture of tetramethyi fructose and trimethyl glucose, which two 

 compounds could be readily separated by distillation at the 

 Gaede pump. 



The tetramethyi fructose has not the butylene oxide struc- 

 ture indicated in formula III , and being very unstable towards 

 permanganate, it conforms in general to the new type of 

 hexoses known as ethylene oxide sugars ; from the fact of its 

 giving on oxidation a lactone, formula IV is assigned to the 

 new tetramethyi fructose, since this formula readily accounts 

 for the formation of an a.-hydroxyacid which must have been 

 the precursor of the lactone. 



CH3 • OMe CHaOMe 



I I 



— COH .COH 



I 0/1 



CH-OMe XH 



O I I 



CH • OMe CH • OMe 



I I 



— CH CH • OMe 



I I 



CH.OMe CH^OMe 



III. IV. 



The fact that sucrose itself, on hydrolysis, yields glucose and 

 ordinary butylene oxide fructose is explained by the assump- 

 tion that the ethylene oxide form of fructose is really formed 

 in the first instance, but that it undergoes a molecular trans- 

 formation into the butylene oxide form at the moment of 

 cleavage ; when, as in heptamethyl sucrose, the hydroxyl 

 groups are protected, no such transformation can take place. 

 The existence of a fructose of the ethylene oxide type is of con- 

 siderable interest in view of the evidence for the existence of 

 an ethylene oxide glucose (cf. Irvine, Fyfe, and Hogg, /. Chem. 

 Soc, 191 5, 107, 524). 



In a paper entitled, " Lead Triaryl, a Parallel to Triphenyl- 

 methyl " Krause and Schmitz {Berichte, 1919, 52, [B], 2165) 

 describe a crystalline lead tri-p-2-xylyl, Pb(C6H3Me2)3, in which 



