144 



WALTER JONES 



The four nucleotides 



The four nucleosides 



H0\ 

 0=P O. C B H 8 3 .C 6 H 4 N B 



HO/ 



adenine. nucleotide 



C 5 H 9 4 .C 6 H 4 N 5 



adenine nucleoside 



H0\ 

 0=P O. C 5 H 8 3 ..C 4 H 3 N 2 2 



HO/ 



uracil nucleotide 



C 5 H 9 4 .C 4 H 3 N 2 2 



uracil nucleoside 



HO\ 

 0=P O. C 5 H 8 3 .G 4 H 4 N 3 



HO/ 



cytosine nucleotide 



H0\ 



0=P O. C 5 H 8 3 .C 5 H 4 N 5 

 HO/ 



guanine nucleotide 



H 



OH 



OH 



OH 



C 5 H 9 4 .C 4 H 4 N 3 



cytosine nucleoside 



C 5 H 9 4 .C 5 H 4 N 5 



guanine nucleoside 



Tlie four nucleosides were prepared from yeast nucleic acid before the 

 nucleotides were known, and thus gave experimental probability to the 

 tetra-nucleotide structure of yeast nucleic acid, which up to that time had 

 been simply speculative. 



The chemistry of the nucleosides is just what one would suppose a 

 priori, and it follows closely that of the simple nitrogen derivatives. They 

 offer two possibilities, (1) hydrolysis, (2) deaminization. Thus by hy- 

 drolysis, adenosine and guanosine are decomposed into pentose and the 

 respective purine bases. 



C 8 H,0 4 .C B H 4 N B + H 2 - C 5 H 10 5 + C 5 H 5 N 5 



adenosine pentose adenine 



B H,0 4 .C B H 4 N B + H 2 = C 5 H 10 5 + C 5 H 5 N 5 O 



guanosine pentose guanine 



