CHEMISTRY OF NUCLEOSIDES AND NUCLEOTIDES 159 



sorption spectrum indicates a 9-glycoside"° and with nitrous acid it is con- 

 verted into xanthosine. The formula shown on page 152 is confirmed by 

 synthesis. 



c. Uric Acid Riboside 



The nucleoside is present in beef blood. It is hydrolyzed in acid to D-ribose 

 and uric acid"^ and is probably a 9-glycoside.'^^ 



d. Cordycepin (9-cordyceposyladenine) 



The mould Cordyceps militaris (Linn.) contains an antibiotic, cordy- 

 cepin,"^ which gives on hydrolysis adenine and a deoxyaldopentose, cordy- 

 cepose. Cordycepin is probably a 9-glycoside with the structure XIX."* 



CHj 



I I 



CH-CHOH-CH 



I I 



NH 



N 



XIX 



Cordycepin 



e. Spongothymidine 



This occurs in the sponge Cryptotethia. It yields thymine on hydrolysis 

 but the sugar component has not been fully identified."^' "^'^ 



/. Orotidine 



A mutant of the mould Neurospora crassa contains a glycoside of orotic 

 acid. On hydrolysis it yields ribose and orotic acid."^ 



g. Vicine 



Vetch meal contains a pyrimidine glycoside, vicine."^ It can be hy- 

 drolyzed by acids to D-glucose and the pja-imidine divicine."^ Evidence for 

 its structure is not entirely satisfactory. [Cf. Bendich, Chapter 3.] 



"" R. Falconer and J. M. Gulland. J. Chem. Soc. 1939, 1784. 



1" A. R. Davis, E. B. Newton, and S. R. Benedict, J. Biol. Chcm. 54, 595 (1922). 



"^ R. Falconer and J. M. Gulland, J. Chem. Soc. 1939, 1369. 



"^ K. G. Cunningham, S. A. Hutchinson, W. Manson, and F. S. Spring, J. Chem. Soc. 



1951, 2299. 

 "< H. R. Bentley, K. G. Cunningham, and F. S. Spring, /. Chem. Soc. 1951, 2301. 

 "* W. Bergmann and R. J. Feeney, J. Am. Chem. Soc. 72, 2809 (1950). 

 "** According to a private communication from Drs. W. Bergmann and D. Burke, 



Yale University, spongothymidine is an arabinoside [The Editors]. 

 i'« A. M. Michelson, W. Drell, and H. K. Mitchell, Proc. Natl. Acad. Sci. U. S. 37, 



396 (1951). 

 1'^ H. Ritthausen, Ber. 29, 894, 2108 (1896). 

 "8 P. A. Levene, J. Biol. Chem. 18, 305 (1914). 



