284 



ANNUAL REPORT SMITHSONIAN INSTITUTION, 1942 



ing process for riboflavin. It is one thing to make such a compound 

 in the laboratory when one is interested in making perhaps a gram 

 or two of it, but quite another thing to do it on a large scale with rea- 

 sonably good yields. The manufacture of these vitamins is carried 

 out in typical manufacturing equipment, although it is not made on 

 anywhere near the scale to which our friends in the heavy chemical 

 industry are accustomed. 



During the course of Goldberger's work on the pellagra-preventing 

 factor, he was able to produce a syndrome in rats which was called rat 

 pellagra when the rats were fed on diets deficient in this pellagra- 



H3C 



H3C 



O" 



rlboae 



^H2(CH0H)3CH20H 

 H3C PjNH 



^H2(CH0H)3CH20H 

 H3Cr^NH 



C6II4NO2 (P) 



H3C 



ls^N=H. 



H2 



H3C 

 H3C 



CH2(CH0H)3CH20H 



ls^N]l2 



NH 

 OCJ^CO 



DC Sx'nH 

 CO 



Alloxan 



CH2(CH0H)3CH20H 

 N N 



H3C 

 H3C 



oco 



N CO 



CO 

 NH 



Riboflavin 



Figure 9. — Karrer and Meerwein synthesis of I'iboflavin, (Karrer and Meerwein, 

 Helv. Chim. Acta, vol. 18, p. 1130, 1935.) 



preventing factor. However, in 1935 Gyorgy showed that rat pellagra 

 was not caused by a deficiency of the pellagra-preventing factor but 

 by a deficiency of a separate factor which he termed vitamin Be, now 

 known as pyridoxine. This compound was isolated by Drs. Keresztesy 

 and Stevens in the Merck Laboratories and at about the same time in 

 other laboratories by Lepkovsky, Kuhn, and Ichiba and Michi. Its 

 synthesis was accomplished in the Merck Laboratories in 1939 by Drs. 

 Harris and Folkers. As may be seen from figure 10, the synthesis is 

 not simple, but in spite of this a number of good classical organic 

 reactions have been used in its preparation. 



