CHEMISTRY OF RIBOSE AND DEOXYRIBOSE 11 



appear to be outmoded. Besides minor variations, such as the use of both 

 "deoxyribose" and "desoxyribose," a trivial name — "thyminose" — has 

 been adopted by some authors. Although this trivial name is found rarely 

 nowadays in chemical literature, it persists to some extent in contemporary 

 publications relating to the biological sciences. 



Attempts have been made to systematize the nomenclature of deoxy- 

 sugars. Bergmann and his co-workers^ introduced the ending "desose" 

 to denote a deoxysugar and referred to II as ribodesose. Probably the best 

 suggestion for systematizing the names of deoxysugars was made l)y Sow- 

 den,^ who proposed that the stereochemistry of the hydroxy 1 groups in 

 deoxy-pentoses and -hexoses should be denoted by a prefix. On this system 

 II is named D-er?/</?ro-2-deoxypentose. The dotted outline denotes the 

 portion of the sugar molecule to which the prefix relates. 



Athough from the chemical ^•iewpoint this latter system of nomencla- 

 ture is probably the most satisfactory, it is not proposed to use it in this 

 review and instead II will be referred to as 2-deoxy-D-ribose. In this way 

 continuity and familiarity will be maintained with the nomenclature 

 adopted in the majority of papers relating to aspects of the chemistry of 

 II. In a survey summarizing the chemistry of ribose and deoxyribose, it 

 is considered to be important that changes in nomenclature from that 

 generally adopted by previous authors should be minimized. 



Although this account will be concerned primarily with a description 

 of the chemistry of D-ribose and 2-deoxy-D-ribose, with particular emphasis 

 on those aspects of the subject which relate directly to nucleic acids, refer- 

 ence will be made to other pentose derivatives whenever they serve to 

 illustrate by analogy or comparison the main theme of this chapter. 



II. Occurrence of D-Ribose and 2-Deoxy-D-Ribose 



The only sugars found so far as components of nucleic acids are D-ribose 

 (I) and 2-deoxy-D-ribose (II). 



Although KosseP recognized in 1891 that acidic hydrolysis of what is 

 now called ribonucleic acid liberates a carbohydrate derivative and three 

 years later Hammarsten^'' demonstrated that this sugar component was a 

 pentose, some fifteen years elapsed before Levene and Jacobs"- '- succeeded 

 in isolating the sugar in crystalline form and identifying it as D-ribose, at 

 that time an unkno\Mi sugar. Its identification was based on the facts that 

 it differed in its physical constants from the crystalline pentoses (L-arabi- 



7 M. Bergmann, H. Schotte, and W. Lechinsky, Ber. 55, 158 (1922). 



8 J. C. Sowden, J. Am. Chem. Soc. 69, 1047 (1947). 



'A. Kossel, Arch. Anat. u. Physiol., Physiol. Abt. 1891, 181. 

 '0 O. Hammarsten, Z. physiol. Chem. 19, 19 (1894). 

 " P. A. Levene and W. A. Jacobs, Ber. 41, 2703 (1908). 

 '2 P. A. Levene and W. A. Jacobs, Ber. 42, 1198 (1909) ; 44, 746 (1911). 



