CHEMISTRY OF RIBOSE AND DEOXYRIBOSE 29 



The simplest type of compound of this class, namely that formed by 

 reaction between ammonia and D-ribose, was investigated by Levene and 

 La Forge. '^2 D-Ribose was treated with dry methanolic ammonia and the 

 nbosimine (XXX or one of its cyclic tautomers) obtained was further 

 treated with hydrogen cyanide in an attempted Kiliani-type synthesis 

 of two epimeric hexosaminic acids. When less rigorously anhydrous con- 

 ditions were employed, a diribosylamine was obtained, but neither of these 

 derivatives of D-ribose has been thoroughly studied. Interest in the syn- 



H— C=NH 



H— C— OH 



H— C— OH 



H— C— OH 



I 

 CH2OH 



XXX 



thesis of vitamin B. led to the investigation of arylamine-N-ribosides. A 

 brief but adequate review of the products of reaction between D-ribose 

 and anihne was provided recently by Honeyman and Tatchell '^^ In 1937 

 Kuhn and Strobele'^" condensed D-ribose with 2-nitro-4,5-dimethylaniline 

 by heating in alcoholic solution in the presence of 2-3 % ammonium chlo- 

 ride. The product on acetylation yielded a triacetate and gave a monotrityl 

 derivative in high yield on tritylation and on the basis of these results 

 was considered to be iV-2-nitro-4,o-dimethylphenyl-D-ribofuranosylamine. 

 Owing to the possibility of isomerizations taking place, during both the 

 acetylation and tritylation reactions, the arguments in favor of the furanose 

 structure cannot be considered convincing. Moreover, it is well known that 

 trityl chloride will react with secondary hydroxyl groups in certain circum- 

 stances^^^ and is not a specific reagent for primary hydroxyl groups. 



An extensive series of investigations concerning the reactions of arylamines, and 

 in particular aniline, with D-ribose was reported in 1945-46 by Berger, Lee and co- 

 workers. They concluded that condensation at low temperatures of arylamines with 

 D-ribose in alcoholic or aqueous alcoholic solution, with traces of acid as catalyst, 

 yields A^-aryl-a-n-ribopyranosylamine. If the reactants are condensed at the reflux 

 temperature of the solvent A^-aryl-a-o-ribofuranosylamines are formed. Configura- 

 tional assignments were based on mutarotation studies on the products. In view of 

 subsequent work by Barclay et al.,^^^ this is a doubtful criterion for distinguishing 

 between a- and ^-anomers of .V-glycosides. The A'-aryl-p-rib opyranosylamines could 



1" P. A. Levene and F. B. La Forge, /. Biol. Chem. 20, 433 (1915). 



'" J. Honeyman and A. R. Tatchell, /. Chem. Soc. 1950, 967. 



"^ R. Kuhn and R. Strobele, Ber. 70, 773 (1937). 



'" R. C. Hockett and C. S. Hudson, /. Am. Chem. Soc. 56, 945 (1934). 



"« J. L. Barclay, A. B. Foster, and W. G. Overend, Chemistry & Industry 1963, 462. 



