Ryan—On the Synthesis of Glucosides. 513 
Tetracetyl-B3-naphthylglucoside.—A mixture of 0°7 g. 3/3 naph- 
thylglucoside and 0-7 g. anhydrous powdered sodium acetate was 
heated to incipient ebullition in a porcelain dish with 4 c¢.c. acetic 
anhydride. The flame was removed, and the reaction which was 
violent was allowed to go on until the solid had dissolved. On 
pouring the contents of the dish into a large quantity of cold 
water a yellow oily mass, which quickly solidified, separated out. 
It was recrystallized from hot alcohol, from which it separated in 
the cold as long branching needles. It was dried at 105°C., and 
melted at 134-1386° C. 
01284 gave 0°2873 CO, and 0:0628 H,0. 
CH,,Oy requires C 60°8, H 5-48, 
Found C 61:0, H5:43. 
Tetracetyl-(3-naphthylglucoside is scarcely soluble in cold 
water, soluble in cold alcohol, readily soluble in benzene, ethylic 
acetate, chloroform, ether, and hot alcohol. The crystals viewed 
with a polarising microscope are scarcely visible when the Nicols 
are crossed. It is hydrolysed with great difficulty by the suc- 
cessive actions of potash and sulphuric acid. Emulsin has no 
action on it. It would thus seem that the conversion of the 
hydroxy groups of a 3 glucoside into the corresponding acetoxy 
groups, without any other change in the configuration of the 
molecule, destroys its capability of being hydrolysed by emulsin. 
An unsuccessful attempt to synthesise arbutin from aceto- 
chloroglucose hydroquinone and potash seemed to indicate that a 
substituting radicle in the paraposition to the ‘OH group inter- 
fered with the reaction. To test this I tried to obtain by a similar 
experiment the glucosides of p.-nitrophenol, and again with a 
negative result. In order to find whether the failure of the 
reaction was due to the nature or position of the group, I examined 
the behaviour of the three cresols towards acetochloroglucose, with 
results which show that the position of the radicle does not explain 
the failure in the synthesis of arbutin. It is rather to be attributed 
to the negative nature of the second radicle which is confirmed by 
Michael’s success with methylhydroquinone, in which the negative 
nature of the second group is removed by its conversion into the 
methoxy group. 
