x THE NUCLEO-PROTEIDS 459 



It gives the reactions of Millon, Adamkiewicz, and Vogel [the tyrosin, 

 tryptophane, and sulphur reactions]. Umber 1 has also investigated 

 the dissociation of this nucleo-proteid by means of pepsin and trypsin. 

 When boiled with water it forms a nuclein having this percentage- 

 composition : 



C 43-62 H 5-45 N 17-39 P 4'48 S 0'728 28'33 



This compound Hammarsten had previously described under the 

 name of '^-nucleo-proteid.' 



According to Gamgee and Jones 2 the polarisation of the nuclein 

 bodies of the pancreas is 



a-nucleo-proteid . . . a D = +37*8 

 Nuclein . . . . a D = + 64'4 



The pancreas contains all the four purin-bases, 3 but Bang 4 pre- 

 pared from Hammarsten's pancreas-nucleo-proteid a nucleic acid 

 containing only guanin C 5 H 5 N 5 O, and called it, therefore, guanylic 

 acid. 5 To this acid he gave the following structural formula : 



OH OH 



\/ 

 C 5 H 4 N 5 P C 3 H 5 (OH)C 5 H 9 5 



(guanin) (glycerine-pentose radical) 



o 



C 5 H 4 N 5 -0-P-0-C 3 H 5 (OH)C 5 H 9 5 



O O 

 \/ 

 C 5 H 4 N 5 -0-P-0-C 3 H 5 (OH)C 5 H 9 5 







I 

 C 5 H 4 N 5 P OH 



OH OH 



/3-guanylic acid. 



Quite recently, owing to having used a \ instead of 2 per cent 

 NaOH for isolating the guanylic acid, Bang and Raaschou 6 obtained a 



1 F. Umber, Zeitschr.f. klin. Med. 43. Hefte 3 and 4 (1901). 



2 A. Gamgee and W. Jones, Hofmeister's Beitrage, 4. 10 (1903). 



3 Y. Inoko, Zeitschr.f. physiol. Chem. 18. 541 (1893). 



4 J. Bang, ibid. 26. 133 (1898) ; 31. 411 (1900) ; 32. 201 (1901). 



5 Ivar Bang, ibid. 26. 133 (1898) ; and 31. 411 (1901) ; 'Mindre Middelelser om 

 Guanylsyren,' Arch, f, Mathem. og Naturvidenskdb. 24. 



6 Ivar Bang and C. A. Raaschou, Hofmeister's Beitrage, 4. 175 (1904). 



