457 



Pyrroles, Porphyiins and Related Compounds 



931 Vitamin Bi^ (Cyanocobalamin, a-(5,6-Dimethylbenzimidaz0lyl) 

 cobamide cyanide), Ce3HssOi4Ni4PCo, dark red crystals 

 which blacken near 212° and do not melt below 320°, 

 [a]6563"^ —59 ±9° (dilute aqueous solution). 



NH2COCH2 CH.CHoCONHz 



CH2CONH2 

 CH2CH2CONH2 



HOCH2 



Vitamin B12 activity has been detected in fermentation 

 broths from many microorganisms, e.g. Streptomyces 

 griseus, S. antibioticus, S. roseochromogenes, Mycobacte- 

 rium smegmatis, Lactobacillus arabinosus, propionibacte- 

 ria. Crystalline material has been isolated from some of 

 these. For primary fermentations, Streptomyces olivaceus 

 is probably the best producer (3.3 mg. per liter). 



Dorothy Crowfoot Hodgkin, Jennifer Kamper, Maureen 

 MacKay and Jenny Pickworth, Nature 178 64 (1956). (Struc- 

 ture) 



W. H. Sebrell, Jr. and Robert S. Harris, "The Vitamins," 

 Robert S. Harris, Donald E. Wolf, Karl E. Folkers, H. M. 

 Wuest, Thomas H. Jukes and William L. Williams, Vitamin B12, 

 Academic Press Inc., New York, 1954 Vol. I Chap. 3, pp. 396- 

 524. (A review) 



