532 Mr. W. J. Young. Hexosephosphate formed by [July 30, 



tures in a vacuum over sulphuric acid, decomposition occurred and free 

 phosphoric acid was formed. The solution was found to give Mohlisch's 

 a-naphthol reaction. It reduced Fehling's solution only after some hours in 

 the cold, rapidly on boiling : this reduction may be due to the hydrolysis of 

 the compound with formation of a reducing hexose. This is known to take 

 place, as an alkaline solution of the sodium salt that had been left standing 

 for two or three days at room temperature was found to contain free 

 phosphate, and a lsevorotatory substance which reduced Fehling's solution 

 in the cold in a few minutes. The same change was brought about more 

 rapidly when the solution was boiled. 



The acid was found to have a less reducing power when boiled with Pavy's 

 ammoniacal copper solution than corresponded to an equivalent quantity of 

 glucose. Thus five preparations from glucose gave reductions of 0'754, 

 0'788, 0*767, 0732, and 0-800, an equivalent quantity of glucose being taken 

 as 1. No osazone could be obtained, as on heating with phenylhydrazine 

 acetate decomposition took place, and phenylhydrazine phosphate was 

 formed. Attempts were also made to prepare insoluble hydrazones or 

 osazones with phenylhydrazine, methylphenylhydrazine, benzylphenyl- 

 hydrazine, parabromophenylhydrazine, and nitrophenylhydrazine, but in 

 no case was any success attained. 



No differences could be detected between the acids obtained from glucose, 

 fructose, or mannose. They all yielded the same products on hydrolysis, 

 formed salts having the same properties, and had approximately the same 

 dextro-rotatory power. Table III gives the rotations of a number of 

 preparations of these acids. 



Table III. 



No. 



Origin. 



Grammes per 

 10 c.c. 



Observed rotation 

 in 4-dm. tube. 

 + 



Temp. 



+ 



1 



Glucose 



-079 



0-097 







20 



3 °07 



2 





0-539 



0-671 



18 



3 11 



3 





246 



0-364 



19 



3 -70 



4 





0-114 



0-161 



16 



3 -53 



5 





0-088 



0-131 



13 



3 72 



6 





-178 



0-278 



16 -5 



3-90 



1 





0-148 



0-179 



16 



3 -02 



8 





0-247 



0-333 



15 



3 -38 



9 





-529 



0-695 



16 -5 



3 -28 



10 





-425 



-560 



25 



3 -29 



11 





0-247 



315 



16 -5 



3 -19 



12 





0-314 



-416 



18 



3 -31 



13 





0-143 



0-181 



17 



3 -15 



14 



0-152 



-189 



19 



3 -12 



15 





555 



-926 



17 



4-17 



16 



Yeast -juice 



0-053 



0-074 



13 



3 -50 



