3 o SCIENCE PROGRESS 



pound of phosphoric acid with a carbohydrate and a pyrimidine 

 complex, as is shown by its behaviour on hydrolysis. 



H0 X 

 O^P-C 6 H 10 O4-C5H 5 N 2 O 2 +2H 2 O=H3PO4+C 6 H 12 O 6 +C 5 H 6 N 2 O 2 



HO Nucleotide Thymine 



On the other hand, fermentation of nucleic acid yielded a 

 nucleoside which was proved by hydrolysis to be a compound 

 formed of a carbohydrate with a purine base ; thus 



C 6 H„0 5 - C 5 H 4 N 5 + H 2 = C 6 H 12 6 + C 5 H 5 N 5 



Nucleoside Guanine 



Thymus nucleic acid is accordingly looked upon as a 

 tetranucleotide formed by the union of four mononucleotides 

 which differ only in their nitrogen ring components. In a 

 recent communication W. Jones and B. E. Reid (/. Biol. Chem. 

 191 7, 29, in and 123) have shown that by the action of dilute 

 ammonium hydroxide yeast nucleic acid yields a dinucleotide 

 containing adenine and uracil of the formula 



H0 X 

 O^P - O - QH 7 3 - C 5 H 4 N 5 



J-JO Adenine complex 



o 



H0 X I 



0=P - O - C 5 H 7 2 - C 4 H 3 2 N 2 



J-JO Uracil complex 



The chief point of interest is that the two mononucleotides are 

 here united to each other through their carbohydrate com- 

 plexes and not through the phosphoric acid residues, as was 

 at one time thought likely. This is proved by the fact that 

 the dinucleotide yields a tetrabrucine salt and must conse- 

 quently have four hydroxyl groups. From the behaviour of 

 yeast nucleic acid itself towards reagents it is concluded that 

 all the four nucleotides in this compound are similarly united 

 to each other through their carbohydrate groups. 



During the quarter under review a series of important papers 

 have been published by Willstatter and his pupils on the 

 Anthocyanines, or red and blue colouring matters of a number 

 of common flowers. The papers were published in the Annalen, 

 191 6, 412, 1 13-251, and it is hoped to give an account of some 

 of their work in a future number. 



Several important papers connected with carbohydrates 



