the products of the reaction with acetic anhydride and benzoyl chloride 
could not as yet be obtained in a crystalline form. 
They are not liable to fermentation but do not prevent the fermen- 
tation of any free glucose, although they retard the same. 
The simultaneous formation of various isomeric mono- and diformal- 
olucosides may, as will be easily seen, explain the unsatisfactory result. 
Galactose yielded products comparable with those obtained from 
glucose. The indistinctly crystalline methylenegalactoside (monoformal 
derivative) seems, however, to be a pure substance as the melting 
point (203) remained unaltered; [alp (in 2°/, aqueous solution) = 
+ 124°.8. It is still being investigated. 
Fructose yields a well-erystallised formalmethylenefructoside ; when 
preparing the same a 50°/, sulphurie acid should be used. Melting 
point 92°; [a@]p (2°/, aqueous solution) = — 34°.9. 
d-Sorbose yields a derivative melting at 54° and [el p (2°/, aqueous 
solution) = — 25°. Rhammose yields a product melting at 76° and 
[a|p [0.4°/, aqueous solution) = — 18°; mannose also yields a crys- 
talline derivative. 
The (mono)methyleneglucosides also derive a certain importance 
from the analogy which they show, as regards their properties, with 
ordinary canesugar. In the same way as the latter has been formed 
from glucose and fructose, they are also formed, with the loss of 
two carbonyl groups, from two aldehydes from which one mol. of 
water has been eliminated. The reducing power is lost; towards 
phenylhydrazine they have become indifferent. On boiling with dilute 
acids, however, the components are regenerated. 
It cannot be a matter of astonishment that the methylglucosides 
are quite as capable as the hexites, the oxy-acids and the sugars to 
give condensation products with formaldehyde. They are formed in 
abundance by simply melting the powdered glucosides with dry 
trioxymethylene. 
In a properly crystallised state were obtained the formalderivatives 
of methylmannoside [m.p. 127°, [alp = + 10.5], of g-methyl-d-gluco- 
side m. p. 186°, inactive] and of «- and g-methyl-d-galactoside. 
The derivatives of a-methyl-d-glucoside and of amyl- and aethyl-d- 
glucoside are viscious liquids. 
It is worthy of notice that saccharose melted with trioxymethylene 
is decomposed with the formation of a mixture of formalderivatives 
of glucose and fructose, from which the latter was separated in a 
crystalline condition. 
