VITAMINS 



187 



THIAMINE AND ITS MOIETIES 



Thiamine (vitamin Bi, aneurine) was the first vitamin shown to be 

 required by a filamentous fungus. Thiamine deficiency in man is known 

 as beriberi. Certain fungi and other microorganisms resemble man in 

 that they are unable to synthesize this vitamin. It is probably required 

 in the metabolism of all forms of life, and its function, to a large extent, is 

 believed to be the same in all organisms. 



Schopfer (1934) demonstrated that Phycomyces blakesleeanus failed to 

 grow in a synthetic medium unless thiamine was added. This was a 

 stimulus for numerous studies on vitamin deficiencies of fungi. The 

 chemical synthesis of thiamine, in 1936, was another important step in 

 vitamin research. The student is referred to Williams and Spies (1938), 

 Rosenberg (1942), and Schopfer (1943) for information on the history, 

 synthesis, and natural occurrence of thiamine. 



The structural formula for thiamine is 



N=C— NHrHCl 



CH,— C C 



-CH,— N 



/ 



CHs 



c==c— 



CH2— CH,OH 



Cl CH — S 

 N— CH 



Thiamine chloride hydrochloride 



The thiamine molecule contains two ring structures, a substituted 

 pyrimidine and a substituted thiazole. The pyrimidine moiety has the 

 following formula: 



N====C— NH2 



CH, 



N 



C— CH2X 



CH 



Thiamine pyrimidine 

 2-Methyl-4-amino-5-methylpyrimidine 



X in the substituted methyl group on C5 may be hydroxyl, chlorine, 

 bromine, etc. The thiazole moiety has the following formula: 



CH3 



C= 



=C— CH2— CH2OH 



N 



/ 



V 



X 



CH- 



Thiamine thiazole 

 4-Methyl-5-/3-hydroxyethylthiazole 



