ANEURINE (thiamine) 



Riboflavine was adsorbed much less strongly than aneurine by Amber- 

 lite IR-ioo and was readily eluted by a more dilute acid ; the two 

 vitamins were thus readily separated by adjusting the time of contact 

 with the resin. 



References to Section 2 



1. U. Suzuki, T. Shamimura and S. Okade, Biochem. Z., 191 2, 43, 89. 



2. E. S. Edie, W. H. Evans, B. Moore, G. C. E. Simpson and A. 



Webster, Biochem. J., 1912, 6, 234. 



3. C. Funk, J. Physiol., 1913, 46, 487 ; Brit. Med. J., 1913, 1, 814. 



4. B. C. P. Jansen and W. F. Donath, Proc. K. A had. Wetensch. 



Amsterdam, 1926 29, 1390. 



5. H, W. Kinnersley and R. A. Peters, Biochem. /., 1928, 22, 419 ; 



1933. 27, 225, 232. 



6. B. C. Guha and J. C. Drummond, ihid., 1929, 23, 880. 



7. R. R. Williams, R. E. Waterman and J. C. Keresztesy, /. Amer. 



Chem. Soc, 1934, 56, 1187. 



8. L. R. Cerecedo and D. J. Hennessy, ibid., 1937, 59, 1617 ; L. R. 



Cerecedo and F. J. Kaszuba, ibid., 1619 ; L. R. Cerecedo and 

 J. J. Thornton, ibid., 1621. 



9. D. S. Herr, Ind. Eng. Chem., 1945, 37, 631. 



3. CHE2VUCAL CONSTITUTION OF ANEURINE 



The chemical nature of vitamin B^ was elucidated by a brilliant 

 series of investigations carried out by R. R. Williams and his col- 

 leagues ; these have been described in a monograph by Prof. Williams.^ 

 The key to the structure of vitamin B^ was found in the action of 

 neutral sodium sulphite solution ; at room temperature ^ this cleaved 

 the molecule into two halves according to the equation : 



CizHisN^SOCla + Na^SOa -> CeH^NaSOa + CeH^NSO + 2NaCl. 



The substance, C6H9N3SO3, on hydrolysis with acid ^ yielded ammonia 

 and another substance, C6H8N2SO4. Both these substances on treat- 

 ment with water at 200° C. yielded sulphuric acid and, with alkali, 

 sulphurous acid, proving the presence of a sulphonic acid group in 

 both. The two compounds gave ultra-violet absorption spectra 

 characteristic of a pyrimidine nucleus, and this was confirmed by the 

 conversion * of the compound, CgHgNgSOa, into 4-amino-2 : 5-dimethyl- 

 pyrimidine : 



N=C— NHa 



I I 

 CHg— C C— CH3 



Un 



12 



