250 



VITAMINS 



which proved to be effective against pernicious anemia in amazingly 

 small doses (Fig. 9-14). The new material, designated vitamin Bio, 

 contained 4.4 per cent cobalt, 2.3 per cent phosphorus and had the formula 

 C61-64H86-92N14O13PC0 (molecular weight about 1350). Although the 



Courtesy of Abbott Laboratories. 

 Fig. 9-14. Vitamin Bio crystals (x 200). 



complete structure is not yet known, several fragments of the molecule, 

 including 5,6-dimethyl benzimidazole, have been identified after acid 

 hydrolysis. Surprisingly, this substance itself showed full vitamin B12 

 activity for rat growth when tested in 5 mg. daily doses. Other hydrolysis 



HoCC 



^ 



H 



,N, 



\ 



CH 



X'^ N 



H H 



5,6-Dimethyl benzimidazole 



products identified are propanolamine (CH3CHOHCH2NH2) and a phos- 

 phorylated derivative of the 5,6-dimethylbenzimidazole (ribose-3-phos- 

 phate attached to the N at position 1). Vitamin Bio also contains a 



